Senior Seminar in Neural and Behavioral Sciences Forum
Comments are posted in the order in which they are received, with earlier postings appearing first below on this page. To see the latest postings, click on "Go to last comment" below.
Name: Rebecca Ro
Date: 2002-01-29 20:17:07
Link to this Comment: 776
Nature or Nurture? There is interplay between both nature and nurture in learning and studying human behavior. I think genetic and evolutionary considerations are both useful and dangerous for thinking about human behavior. Behavioral genetics and evolutionary psychology are different in that behavioral genetics looks at the role of genetic influences as contributors to individual differences, rather than on their role in accounting for shared species characteristics. Behavioral genetics looks for genetic explanations of behavioral traits. However, there are ethical, legal, and social implications of behavioral genetics.
Information about genes I think will influence the practice of medicine and psychiatry in the prevention and treatment of many disorders. Genes partially contribute to variations in behavior among people and to complex behavioral disorders. But it is also shown that environmental influences can initiate changes in gene expression. We have to be careful not to jump to any conclusions and remain optimistic. As specific genes are identified, we can explore how these interact with environmental factors in development.
I look at human behavior as the exercise of free will. Individuals have control over their behavior, their behavior is not determined by biology alone. Why do individuals change on average between two ages? However, there are some human behaviors that cannot be explained causally. Chance events do happen that are beyond our own control.
In genetic/evolutionary considerations, people fear what they do not know or what sounds too complicated. Therefore, it is important to try and make concise explanations and what is being done and be as clear as possible. The book review, And the Blood Cried Out I found interesting because I worked with Harlan Levy's wife during the summer. Unfortunately, scientific evidence used in court many times goes above all parties involved, opposing counsel, judge, and the jury. Therefore, it can make deciding a case difficult. One should also not look at complicated evidence as being correct/incorrect without further proof and clarification.
Many more observations and information is needed to clear uncertainties, but as we advance and build upon past ideas, understanding human behavior might be made clearer. Both genetics and evolution can be used in exploring human behavior.
Date: 2002-01-30 00:14:38
Link to this Comment: 777
I think an important question, though, is whether or not the expansion of scientific knowledge is inherently sufficient to justify the clearly intricate and dangerous new problems raised by applications of evolutionary theory and, in particular, genetics. To briefly mention a few of these, I think genetic explanations for behavior clearly raise the specter of eugenics (do we really want to selectively breed our population for behavioral/ other traits? ),; they could lead to enormous levels of discrimination in hiring practice, insurance, education, and any other number of fields; and, more subtly, people are likely to interpret information that a behavior has a genetic basis as indicating that that behavior is uncontrollable, which in most cases is clearly incorrect. There seems to be a knowledge (good) versus applications (bad) dichotomy in my thinking about these fields; my thoughts on the topic are much more complex than I can say in this posting. In fact I actually think that regardless of whether they are 'good' or 'bad,' both the acquisition of new knowledge about the genetic/ evolutionary basis of behavior and the application of that knowledge is going to continue to increase at an extremely rapid pace, regardless of any kind of legislative attempt to control it, in this country or elsewhere. Where does that leave us? Hmm….
|First Meeting of Seminar|
Name: jimmy stei
Date: 2002-01-30 22:04:40
Link to this Comment: 781
To me it seems that papers and magazines such as Time are the ones responsible for propagating this deterministic view. When researchers find significant results for study looking into a gene that is associated with memory, these papers try to make a headline by claiming that scientists have found the smart gene. The general public that reads these publications does not necessarily know any better and begins to buy into the deterministic ideas.
I almost worry that people begin to use these genetic predispositions to traits such as alcoholism or aggression as excuses for their behavior. If I convince myself that I have a problem with aggression because of my genes it will be almost impossible then to convince myself that I can get over this problem and become a healthy, functioning member of society. I think that we can get over these predispositions. Alcoholics can go to AA meetings and talk about how they have been sober for years. What does it mean for the brain to be able to convince the body that it does not need the alcohol? Is this really what’s going on? These questions may be more clear-cut than I seem to think but I don’t know…
Name: Caitlin Co
Date: 2002-01-31 01:04:50
Link to this Comment: 783
I've heard criticisms of evolutionary theory that say that things that happened many thousands of years ago, while they might help explain very general human tendencies, cannot account for the intricacies of all our current behaviors. I think one of the big things that leaves evolutionary explanations less than satisfying to many people is how they treat the human race as a single behavioral unit or as very large groups (e.g. males vs. females), not paying much attention to variations within these groups, and in particular ignoring the notion of free will. That's where perhaps the greatest danger lies in evolutionary/genetic explanations. Is it possible that domestic abuse will be justified on the grounds that there is an evolutionary reason for males to behave violently when they think they've been cuckolded? Or will XYY men be acquitted of crimes because they are "preprogrammed" to be violent? Hopefully not...the scientific community and the public press need to be careful to stress that these are general tendencies, and as autonomous beings we can control our own behavior. But then, if brain=behavior, are we really autonomous at all? hmmm...
Still, evolutionary explanations for human behavior are somehow very appealing to me, particularly when I think about why people engage in seemingly destructive or maladaptive behaviors, or just whenever I don't understand why we do some of the things we do. Rather than putting limits on evolution's and genetics' explanatory power or drawing boundaries around their territory, it seems that they can contribute to our understanding of almost any behavior; they just need to be considered in conjunction with other theories.
Name: Huma Rana
Date: 2002-01-31 11:06:34
Link to this Comment: 785
Although I think that Cosmides and Tooby’s work is advantageous in that it can help us understand our behavior and our history, I believe that behavioral genetics enters a more serious/dangerous realm. When I read Rothstein’s article in which he warns of the “grievous social consequences” associated of behavioral genetics, I thought he was being a bit dramatic. I gave our society more credit than to think it would revert to eugenics arguments reminiscent of those surrounding The Bell Curve. However, in reading Berkowitz’s accumulation of quotes from modern scientists (some associated with the Human Genome Project), I was shocked to see the common thread of genetic determinism woven into their arguments. I believe it is irrelevant/ridiculous to say that alcoholism, mental illness, homosexuality, intelligence, or various personality traits can be localized to a single gene. I do believe that there is a genetic component to the above- mentioned traits, however, as McInerney stated, “…genes can do nothing by themselves.” It would be a nightmare to see genetics arguments work themselves into public policies, laws, and social hierarchies. However, it seems that behavioral geneticists are a long way from finding substantial, significant, irrefutable results that show causal relationships between genes and behavior. Until then, we should brace ourselves for the myriad of unreliable studies that will be published and watch as they make it to the mainstream media and grace the cover of Time magazine with titles such as, “Gene for Shyness Found!”
Name: caroline r
Date: 2002-01-31 11:23:50
Link to this Comment: 786
Date: 2002-01-31 14:30:05
Link to this Comment: 793
What if technology allows us to replace the undesirable genes in the zygote so that the aggression gene is no longer present in the individual? Can nurture alone cause aggression in this person?
Date: 2002-01-31 14:44:38
Link to this Comment: 794
Genetics also play an important role in human behavior and therefore it is both necessary and useful to study genetics when looking at human behavior. However, I think that genes do not determine behavior nor do they dictate a particular course that an individual must follow. Rather, I agree with the de Waal article that states, “genes, by themselves, are like seeds dropped onto the pavement: powerless to produce anything.” In other words, the environment in which genes exist also plays a crucial role in determining behavior. I also think that there are certain advantages to studying the role of genetics in human behavior. For example, scientists may discover genes that predispose someone to develop a particular mental disorder, so we can then provide a person with that gene an environment that helps prevent that particular mental illness from arising.
Although I think it is important to consider the genetic and evolutionary contributions to human behavior, I think that one should approach these areas cautiously. Several of the articles raised the issue of the misrepresentation to the public by the media and the misinterpretation by the public of scientific findings related to genes. It seems that scientific findings are sometimes presented incorrectly by the media in order to make a story more appealing and to improve ratings. For example, it may be stated that a gene was found that causes a particular behavioral trait, although it is more likely that the gene predisposes a person to developing that trait and that the environment in which the person resides helps determine if that trait will be expressed or not. This type of misunderstanding by the public can be dangerous (consider the examples pertaining to law that Rothstein discussed and some people’s intolerance of people with abnormal conditions), so it is important that when scientists conduct this type of research they also help present the information correctly to the public and help correct any misunderstandings held by the public.
I am fairly certain that genetic and environmental factors both affect human behavior, but I am uncertain of the extent to which these effects occur. Further exploration of the topic throughout the semester and by scientists in the field should hopefully lead us to an even better understanding of this complex issue.
Date: 2002-01-31 16:42:21
Link to this Comment: 795
Name: jess golde
Date: 2002-01-31 17:05:02
Link to this Comment: 796
Name: Nirupama K
Date: 2002-01-31 17:10:25
Link to this Comment: 797
It was great to read a psychology article that actually talked about the importance of biology and evolution of all things in studying the mind. Having just taken an Evolution class, where I wrote my final paper on the evolution of the brain in primates I thought it was great stuff. I think evolutionary considerations are hugely necessary and useful in thinking about human behavior. People often fall into this trap of thinking that society and humans come out of no where. Saying that, oh behavior doesn't come from the brain it comes from society. But where did that society come from itself? It didn't arise out of nothing, and what we are determines who we are.
I also think the discussion of instincts having a much greater say in our minds than we previously thought clears up a lot of things. The notion of 'assocation cortex' certainly did seem to be a cop out way of describing the neocortex because they couldn't pinpoint exactly what it did. I think the EP author went a little too far with his stress on the egalitarianism of evolutionary psychology. Just because not all people have the same ability according to the integration of nature/nurture theory, does not serve to discredit it. In fact, I think it goes pretty far to explain a lot. Even though all humans are very genetically similar, our morphology makes it evident that slight changes can result in significant differences. Changes in hardwiring explain how even siblings brought up in the same environment may excel in very different fields.
Studying human behavior from an evolutionary standpoint give a lot of insight into the creation of our brain's structure and what impact that had on behavior. Archeaologists can determine some typical behaviors for our human ancestors, at the same time changes in the size of different brain areas can be seen. This study also allows us to look at the way our behavior evolved and its true purpose. Behaviors that seem problematic today (ie, aggression, promiscuity) may have evolutionary benefits to be looked at.
Evolution is not an exact science either, however. And even if we gain a greater understanding of how consciousness developed, we still may not come any closer to understanding how consciousness works. Looking at humans (or any species group) as homogenous is a large fallacy in biology that needs to be corrected I think. Instead, gene populations would better be studied as the true units of evolutionary change.
Name: ingrid sol
Date: 2002-01-31 19:06:58
Link to this Comment: 798
One particular example would be in the de Waal (I've read other things he's done) article where he talks about how some evidences for the phenomenon of incest and "early familiarity". He talks about a great example of testing this is a study where they found a culture in Taiwan that had spouses who were raised with eachother. This was compared to a culture where people don't meet till the wedding day. Well, the confounds in this example are extraordinary. When you compare divorce and fertility rates as examples for marital happiness and sexual activity... well, I bet that cultures that are so different in marital relations probably have different views about divorce. I bet divorce occurs less in such family-strong cultures like asia as it would in western cultures where we meet potential spouses in our maturity. There just seems to be such huge openings for confounds. This is just one example, but it is important to realize that we are combining something so exact (protien synthesis receipes) to phenomenon that use a much less technical language. All of these articles remind me of Learning theory and Behavior topics. Several of us are in this class.
Similarly, though all this talking about genetics and cultural differences is interesting, the phenomenon of biased tests was only mentioned once and that was veild and in passing. We learned in Cog. Psych that there are bias tests, not just genes. I think this holds some influence in deciding how we interact with the genetic findings. I think that's very important.
I did find it interesting though when they talked about how protiens are needed to express the patterns and instructions in the genetic material. I think this was an insightful way to look at it, and realize that this is also similar to our use of dopamine/seratonin (etc.) manipulating drugs rather than gene-therapy (heretofor impossible). Though would we eventually go that far?
|Thoughts after session 1|
Name: Paul Grobstein
Date: 2002-02-01 09:44:29
Link to this Comment: 800
1 - There seemed to be consensus that both genetics and evolution ARE useful additions to other ways of exploring/trying to better understand human behavior. I was particularly intrigued by the idea that some aspects of human behavior seem "irrational" (is that really what we mean? would "hard to understand" be better?) EXCEPT in the context of evolution. And no one seemed to doubt the evidence that genes CAN influence behavior, as long as it was clearly understood that genes are an INFLUENCE, not a DETERMINANT.
2 - With regard to evolution, there was, it seems to me, a useful distinction made between generating hypotheses to explore about the causes of human behavior based on considerations of evolution, and accepting that particular evolutionary ideas explained behavior. There are two issues here. One is that one can't "go back" and test evolutionary explanations by directly checking them. If evolutionary thinking is to be used, one has to phrase hypotheses based on it in ways that can be tested (potentially falsified) by observations it is currently possible to make (a similar concern about evolutionary "explanation" arises in other biological contexts, as exemplified by Stephen J. Gould's concerns about "just so stories"). The other issue is to bear in mind that evolution (like genes, which are presumably the intermediary in its influences) are an INFLUENCE, not a DETERMINANT.
3 - I think we need to do some more talking about the "influence" versus "determinant" idea. As discussed, this seems to be a continuum with some genetic (evolutionary?) factors closer to the "determinant" side (sickle cell anemia, PKU problems and mental retardation, schizophrenia?). On the other hand, it was usefully pointed out that even in the more extreme cases, environmental and/or self-induced activities can affect outcomes (as in diet for PKU problems, use of neuropharmacological agents, etc).
4 - I think we also need to do some more talking about whether it is appropriate to talk about a gene for X (eg an "alcoholism") gene. The issues here have to do with "influence" versus "determinant" (as above) but also with how MANY genes are likely to be involved in (influence) any behavior, the likelihood that a given gene influences many behaviors, and the dependence of the influence of a given gene on other genes.
5 - There are clearly significant public policy matters for which the above considerations are relevant. One set of concerns is the extent to which genetic/evolutionary considerations in fact threaten concepts of "free will" and "personal choice". The consensus in the group seemed to be that they don't, because they are influences rather than determinants. This seems worth further discussion, since it is hard at the moment to specify what is meant by "free will" and "personal choice" with enough precision to evaluate whether they might in fact be affected by genes (could particular genes diminish the extent of "free will"? might the extent of "free will" be itself a product of evolution?).
6 - A second set of concerns in the public policy arena is the extent to which genetic/evolutionary explorations might diminish a belief in "free will" and/or "personal choice" in people who are less familiar with the scientific literature. If this is of concern, the issues are what should be done about it, and by whom? Is it a media problem, a science problem? How can one assure broader understanding? On the other hand, an interesting argument was made that people in general may be more sophisticated in this area than many scientists, having in their day to day life abundant experience with genes as an "influence" rather than a "determinant" (people from families with histories of alcohol abuse who act not to continue it).
7 - A third set of concerns in the public policy arena has to do with the potential for discrimination against people based on information about their genetic background. It is, perhaps, in this area that it is most important to assure public awareness of the "influence not determinant" idea. There may also be a need for greater public awareness of the more general biological idea that "normal" is not a well-founded idea, and that "diversity" is itself desirable.
8 - A fourth set of concerns in the public policy arena is, in some ways, the opposite of the concern about diminished "personal choice": with increasing information about genetic influences, people may acquire greater opportunities for personal choice in regard to, for example, choosing characteristics of their offspring. Should this be thought of as "discrimination" or simply as a further enhancement of long-standing practices of individual human beings to influence gene pools (via mate selection, elective abortion, etc)? Are there compelling social issues requiring collective policy decisions or should choices of this kind be left to individuals? Are some situations of the former and some of the latter kind and, if so, what's the basis for such distinctions?
Name: Rebecca Ro
Date: 2002-02-10 16:21:32
Link to this Comment: 892
How much do genes account for individual differences between us? To explore human behavior one needs to look at the relationship and interaction between genes and the environment. We need a greater understanding of how the environment actually affects our genes, leading to the great diversity of human behavior.
According to Chapter 18, gene-environment correlation occurs when people with high genetic values for a trait experience environments with high values for that trait. Chapter 5 spoke about how the ALDH-2 polymorphism shows how genes can relate to behavior . It says that the ALDH2 allele appears to lower the risk for the development of alcohol related problems. This shows that genes operating elsewhere in the body can influence behavior. Everyone has probably heard the saying, “I just have bad genes” when trying to explain a certain action or behavior. We know that genetics influences the likelihood that we may get certain disorders or exhibit certain traits.
From reading the article on the neurobiology of cricket song, I learned that cricket song has a genetically determined component. Studying animal behavior is learning how simple behaviors lead to more complex behaviors. The field of animal behavior looks at understanding the causes, functions, development, and evolution of behavior. The development of behavior is concerned with the ways in which behavior changes over the lifetime of an animal. The evolution of behavior is concerned with origins of behavior patterns and how these change over generations of animals. There are hopes that in understanding animal behavior we can better learn from our own behavior. For instance, giving flies jet lag turned out to have direct implications for understanding circadian rhythm in mammals, even humans.
Why is behavior so difficult to understand? Our behavior not only reflects our general well being, but also how well we relate to our environment. Some organisms are capable of evolving, while others are not. Why is it that some organisms don’t evolve? And have those organisms that evolved, evolved to be adaptable rather than requiring continuing evolution to specialize?
Our mental condition is part of a complex interplay between our biology and our environment. There have been brain structures identified and chemistry which are shown to control behavior. The discovery of brain chemicals (ex: endorphins) leads to an understanding of how behavior can also be a biochemical event. Genetic research leads to identification of certain genes that seem tied to behaviors. Medicines and drugs are produced which also affect and or alter our behavior. There are also scanning devices which show mapping of brain functions. We have only begun to identify the genes that control the molecules of the brain. We can learn about behavior from previous studies and cases. There will always be more advancements.
Date: 2002-02-13 18:49:11
Link to this Comment: 966
We must, however, beware of issues such as the tongue-rolling phenomenon which is unlikely to be inherited; yet this notion has permeated society. There is a danger in ascribing too many traits to genetics that may not be determined or even influenced by genes.
This leads me to the studies that I find irrelevant. While, reading through the various articles from 2001 on the BG news Home Page, I was fascinated and found it difficult to stop reading. I had a strange feeling that I was being sucked into addictive pop bio/psych studies. Most of them were neither conclusive nor significant, but I read them because they were fun and told a great story. One stated that a propensity to get divorced could be found in ones DNA (because monozygotic twins are more likely to have similar patterns of divorce). Another stated, “Researchers suspect that the Chinese love of gambling may also have a genetic component and are keen to begin blood tests on local gambling addicts.” One observation was that 30% of anorexics were born in June. I don’t find these observations to be reliable, as they cannot factor out environmental influences on behavior, but I can’t disregard the correlations either. Regardless of the quality/reliability of research that occurs, people enjoy reading these studies because it gives them something to explain/blame their behavior on. For complex human behaviors and matters of choice there is much more going on than a one-to-one contingency between genes and behavior. Though genes can be identified for things like PKU, downs syndrome, and colorblindness, these behaviors do not generally involve societal pressures, constructs, or reinforcements.
I’m most confused about how to distinguish studies that have relevant genetic/evolutionary considerations and those that don’t. So far, I’ve looked at them on a case-by-case basis, without a finite set of rules to dictate what is a valid line of research and what isn’t.
Date: 2002-02-13 21:19:43
Link to this Comment: 967
The fascinating thing though, was the wondering as to whether the brain would be able to processes this new colour? Would it be able to make a new channel. I do see the distinction and think it's amazing, however I don't see why it would seem so baffling and so much like a miracle.
And a fun question. Is 'sweet' for us 'sweet' for a mouse? Wouldn't it have to do (evolution wise) in a comparison of function? More like sweet being attractive and sour being aversve. Would sugar actually be sweet to a mouse, or would wheat be sweet for a mouse? And because of this, would the chemicals (that bind to the receptors in a mouses mouth and brain to indicate something attractive is on the tongue) be responsive to the same (EXACT) chemicals that trigger our own? For that's the assumption that these tests make, since they're looking for the same chemicals. I'm not sure if this is a valid question, I was just wondering if they can make these assumptions of 'taste'.
Date: 2002-02-13 21:58:28
Link to this Comment: 968
In terms of genetic evidence, linkage and association studies allow you to determine the location of the gene and potentially the sequence of that gene, while heritability studies do not. Heritability studies have the benefit of being much simpler, less expensive, and requiring less equipment, but they are based on a number of potentially faulty assumptions (e.g. that the environmental contribution to the phenotype is the same for MZ vs. DZ twins or that adoption occurs through random placement). In general, especially in terms of evolutionary evidence, the claim that a given trait has an evolutionary or genetic basis is strengthened when multiple observations corroborate the same finding.
It is important to keep in mind that the finding that a behavior has a genetic basis can mean a number of things; the finding that a trait has a genetic basis does not mean that the environmental influence is irrelevant. A number of factors (incomplete penetrance, variable expressivity, etc. etc.) leave the door open for enormous environmental influences on the genetically constrained phenotype.
One question/ uncertainty I have about my answers stems from the Molecular Neurobiology class that I'm taking at Haverford. We have spent the past couple of days going over embryonic development. As I've been thinking about our often incredulous take on one gene's ability to influence a complex behavior, I've been wondering whether some of that incredulity stems from our incomplete/ inadequate appreciation for how the development of the nervous system unfolds. It seems to me that especially if a gene had an effect very early in development, it could have global and complex consequences.
Date: 2002-02-13 22:18:34
Link to this Comment: 970
Name: Caitlin Co
Date: 2002-02-14 01:05:24
Link to this Comment: 976
Admittedly, it's different for behavioral phenomena like coding specificity than for possible genetic coding like tongue-rolling--behavioral phenomena, which are by definition described population norms, can certainly exist without every person behaving that way, whereas a gene "for" a trait is something we could conceivably physically find and would potentially affect people in a more black-and-white way. But it's still a relevant consideration to determining if something has a genetic influence. In what percentage of MZ vs. DZ twins does a trait have to co-occur to convince us of a genetic component? In how many cultures do people have to behave similarly to indicate an evolutionary mechanism?
I think this issue is particularly interesting in relation to evolution, and there are several obstacles to our being able to effectively use and evaluate evolutionary theories of behavior. One, which Liz and Ingrid brought up, is that we don't have a thorough enough understanding of neurological development and what happens on the cellular level to assess the feasibility of explanations involving genetic mutations and the scope of genetic influence on behavior. Another is that our personal frame of reference is in decades, not millions of years--we can't really know what might be possible in the time frame under which evolution works, or how it would look through the many generations. In a way, we both can't think small enough and can't think big enough to make sense of evolutionary theories.
I also wonder how (or if) evolution is happening now. It seems that at least to some extent, we've "beaten" evolution--by doing things like making eyeglasses so the nearsighted don't all stumble off cliffs before puberty and thus allowing the genetically unfit to reproduce, we've greatly interfered with natural selection. Also, the way we think of evolution usually involves random mating at least within a certain geography, but that's hardly what happens, and hasn't for quite some time in human history--so how does that affect the evolution of the species? And "survival of the species" is hard to grasp from the perspective of the individual. Apparently the idea for the individual organism is to propagate its own genetic material--but how does this "incentive" influence our behavior? Maybe animals are operating under some kind of internal calculus whereby they will take a 25% chance of dying in order to save a cousin (or whatever), but humans are of course dealing with more complex issues.
One of the Behavioral Genetics articles said that animals who mate with animals they are genetically very different from have more offspring. But I think Buss says that we are attracted to people we look similar to because they are likely to have similar genetic makeups to our own. So which is more important, reproducing more or having our offspring resemble us genetically more? How do these relative considerations play out in animal behavior, much less human behavior, where sexual selection is a little more complicated than having sexy yet otherwise maladaptive peacock feathers. So are we "evolving" at all these days, or have our manipulations of the environment by now outweighed evolutionary effects? And what will all of this mean millions of years down the road when the evolution that may or may not be happening would have resulted in us all being tetrachromats?
To answer these questions would require, on my part, a better grasp of genetics and neurobiology, and on the scientific community's part, more agreement on how much evidence constitutes "fact". We also need a much longer lifespan to be able to think in an evolutionary manner. In the meantime, I think I'm going to go practice rolling my tongue, as it appears that there may be hope for me after all...
Name: Niru Kumar
Date: 2002-02-14 01:21:27
Link to this Comment: 977
Based on what we read, there seems to exist a lot of general uncertainty about common notions of human behavior inheritance. I think that the basic standard for evaluating it needs to be something objective. I think that observations need to imply something more than a statistical correlation. It is easy to amass statistics, without showing some actual mechanism for inheritance.
In cases were a gene can be identified that is correlated with the behavior, and if the expression of that gene can provide a causal relationship for the behavior, then and only then can we say that relevance exists. Twin studies can be very interesting and engrossing to read about, but I don't know if they are nearly enough to provide relevant information. They show the possibility of a genetic link, but don't actually provide a positive correlation.
The different levels of correlation seen definitely highlight the fact that because we cannot ascertain whether genetics is the key to human behavior, tha other factors are at play. The simple fact that we do twin studies shows that we try to eliminate environmental influences from our look at genetics. But, these influences probably have a significant impact on, at least, how our genes are expressed and how our brain pathways develop.
Name: Mary Schli
Date: 2002-02-14 01:32:02
Link to this Comment: 978
One significant difference of animal observations versus human observations is that one can perform many manipulations on animals that cannot be performed with humans. This can cause a problem because there are certain circumstances in which it is inappropriate to perform manipulations on people that are performed on animals, so one can only speculate that the observations seen in the animals would be similar in humans. However, researchers can use information gained from human data and apply it to animal research in order to investigate the underlying genetic influences on behavior. For example, in the case of Alzheimer’s Disease, researchers have been able to place alleles into mice and have found that these mice show plaques and tangles in the brain that are similar to those in patients with Alzheimer’s Disease. The researchers can then manipulate and test several variables that they are unable to test for in humans in order to better understand the behavior patterns of patients with Alzheimer’s.
In terms of what these observations imply for the importance of other factors, I like Carey’s lemonade analogy. Lemonade is a solution made of many parts and trying to name one part as the sole ingredient would be impossible. By applying this to behavior we find that behavior is complex and thus it is made up of several factors that can interact in statistically meaningful ways. I also think that Carey made an interesting point when he said that “environmental factors always contribute to individual difference in human behavior” since there has yet to be a perfect correlation for identical twins (who have identical DNA) on any behavioral measure. While this certainly seems appealing to me, I wonder about the validity of this statement – perhaps it is our means of measurement (which might not be perfect) that is causing us to obtain values that are close to but not equal to 1. This would then imply that there may be some things that are completely determined by something other than the environment (e.g. genetics) but we can’t observe them since our collection methods are insufficient. I’m not sure what the correct answer to this proposition is, and I’m not sure that we can solve it with our current methods, but perhaps we can move toward a less wrong answer.
Date: 2002-02-14 02:08:02
Link to this Comment: 980
Name: Rebecca Ro
Date: 2002-02-14 14:38:17
Link to this Comment: 988
Specific parenting behaviors can influence child outcomes (ex:Authoritative parents). However, wouldn't it be hard to tell if it is genetics that affecting the child's social interactions and personality or it is the environment in which the child grew up? Or a combination of both?
Also, this isn't relating to behavior--but what about when you to a different climate or location, (ex:down south)--you notice more people with blonde hair than up north. Also, more people up north have curly hair than down south. Why is that? Would the people who have curly hair now, have curly hair if they were born in a place where there is almost no curly haired people? Is it really genetics that determines this or is environment having a role as well?
Name: Rebecca Ro
Date: 2002-02-19 19:16:52
Link to this Comment: 1083
What is intelligence? Is our intelligence determined when we are born or is it the result of interactions between our heredity and our environment? Is intelligence really one thing or is it a variety of things? There are many different conceptions of intelligence. Intelligence could be defined as the capacity to learn from experience. It could also be an adaptation to one's environment. Various psychologists have/had strong views on intelligence (e.g. Piaget). If you take a cognitive psychology class you would learn that there are two types of intelligence: fluid and crystallized intelligence. Gardner developed a multiple intelligence theory (Linquistic, musical, logical-mathematical reasoning, spatial, bodily-kinesthetic, interpersonal; and intrapersonal). This is thereby showing that there are many different factors that can account for intelligence. It is obvious that no one can excel in all areas. Afterall, no one is perfect. The definition of intelligence, genetic influences, and validity and reliability of intelligence tests should be analyzed further. Intelligence to me is being a well-rounded individual. Intelligence is not just having 'book smarts', but also having social skills.
A problem with looking at what influences intelligence—whether it is genetics or the environment is that generally people related to one another live together. Therefore, it is sometimes hard to differentiate if it is really genetics or if it is in fact the environment. Intelligence is not all genes. I would say that genes influence intelligence, but certainly cannot determine intelligence. Both genes and the environment interact with one another. This is what leads us to be unique individuals. Genetics and the environment both are factors in intelligence. There has to be a genetic component of intelligence, according to twin studies. Some adoption studies show that environment plays a factor in intelligence.
The exploration of the genetics of ‘intelligence’ is useful. Genetics could be used to show the connection between different traits and behaviors. Learning and memory are at different stages. Does Ginko really improve our intelligence? There will always be a search for drugs that can help us improve our memory and make us more intelligent. It was interesting to read that the “gray matter in the frontal lobes turned out to be correlated with intelligence.”
There is variability which cannot be accounted for. More studies and observations need to be done to develop a greater understanding of what 'intelligence' actually is. More people need to be looked at who live in the same environment (household), but are not genetically related to each other (adoption). Even though environmental factors could lead family members to be different. We act differently in school, than we do when we are at home with our parents. Many variables need to be looked at such as the relation between IQ and academic achievement.
Why is it that people say first born children are smarter? Is this really true? If intelligence was strictly genes, all the parent's children should be about the same 'intelligence'. Stressful events, parental perspectives, health, family size, socio-economic factors, social multiplier effect, all can influence ‘intelligence’.
Performances on IQ tests are malleable. It is one test given on one day, that in some cases (standardized tests) can affect where you go to school. I think the environment definitely affects ones performance. The environment in which you take tests does make a difference. That is why some people recommend studying in the same room that you are going to be taking the exam in. For instance, I took countless number of LSAT exams, some were in my room, and some were at the Kaplan center. I consistently did extremely well on all the practice exams and when it came to the actual exam, being in the exam room, knowing that this was the test that really counted, my score changed and I no longer got the score I was getting on the practice tests. If it was strictly genes, I should have gotten a 99 percentile on the LSAT exam, or somewhere around there. But I didn't. Or should I have not gotten the same range? What exactly are prep tests teaching? They never helped improve my score--are they really teaching you how to take the exam, or are they teaching you “how to beat the test”? I agree with Professor Grobstein in that “failure to perform well on standardized tests indicates failure to perform well on standardized tests. Period.” I think it is unfortunate that so many colleges and grad schools look so much at standardized tests. Granted standardized tests are standard, so that it is the only way to judge everyone, since different schools grade differently and people take various courses. But there is such a strong emphasis on standardized tests. I know that the LSATS count for about 70%. One of my friends scored phenomenally on the LSAT and had a 'low' G.P.A. However, he got into a top law school, and did terrible in law school. He is a good lawyer, though. He is still one of the smartest people I know, regardless of his G.P.A. in undergrad and in law school. Are the standardized tests really showing that he really is intelligent? What about his grades in school? And what about him not applying himself in school, is that considered ‘intelligent’m not using your full potential (according to the test) ? What about people on the other end of the spectrum—scoring terrible on standardized tests but having a 'top' G.P.A. in college and in grad school? As far as tests in general go, I think it matters how well you can perform under pressure. What kind of day you are having can affect your perfomance. If new tests come about, there needs to be tests which assess a broader range of intellectual abilities. Is it that IQ/standardized tests are really instruments of political and social control?
Name: hiro :)
Date: 2002-02-19 23:50:34
Link to this Comment: 1091
my question is: how do behavioral genetics account for the changes in an individual's behavior over time?
i was facinated to know that there is a sweet taste gene because i love sweets. however, i have realized that i never really liked very sweet food before. now, i love it and i eat more sweets. how has my behavior changed over time? was i programed to change my food preference in such a way because of the genes i have? since genes direct very complicated events, such as programed cell death, i belive that genes can become active at a scheduled point during my physical development and produce proteins to alter the numbers or sensitivity of the taste receptors. or, maybe not the genes but the environmental factors caused the change. maybe the high stress level at college caused me to consume high sugar/calorie food, and what kind of genes for food preference i had didn't really matter. as liz has mentioned, twin studies can be applied in order to test these possibilities. (now, here's another question, which is a little off the topic: do genetics account for how people deal with stress? not everyone responds to stress with higher consumption of sugar.)
the change in one's behavior over time can be said about near-sightedness, too. i believe that near-sightedness is inherited as a dominant trait. so, in this case, the genes are responsible for the shape change of the eye balls. but, do these genes program/determine the timing of the development of near-sightedness? or do they simply increase one's suceptability to the change (meaning that the person may not develop near-sightedness, depending on the environmental factors)? i have also heard that sons of a near-sighted person develop worse eyesight than the same person's daughters. how can the sex difference be explained in terms of behavioral genetics?
|intelligence: fact or fiction|
Date: 2002-02-26 23:16:49
Link to this Comment: 1236
|2 main concerns|
Date: 2002-02-26 23:30:02
Link to this Comment: 1238
Second is that, without this definition, we're not even sure what we're looking for in the brain. What lights up on a brain scan during a task may be decieferable. But what task do we give the individual? And is that applicable to what his 'intelligence' will be used for in all real life situations? How about the difference between intelligence and street-smart wisdom? I find people who are socially inept, wity, sarcastic, and have a good sense of direction to be more 'intelligent' than someone who can recide shakespeare's plays in a time of crisis. Can we measure all these factors at once? We've barely mapped out the regions in the brain, and certainly what we Have done isn't so specific as 'intelligence' (whatever that may be).
Heritibility in brain differences in general is actually very interesting. And may lead us somewhere. But were we expecting anything different? If any of our behavior at all is somewhat heritble then I believe that our question has already been answered: yes, then things in our brain are heritible too.
One thing I did find fascinating is the method behind the mouse genetics. The fact that they can snip out a piece of DNA (including the 'on' tag), put it in the nucleous of a forming cell, and have it used.... i just find that absolutely incredible. Am I correct in predicting that this can be done in humans as well? Because mice aren't 'so much' of a 'lower animal' in the kingdom.
And though this question implies that I may think that humans are alterable, I don't necessarily believe that we will be able to change anything in our behavior so easily through gene therapy. My main concern with this is that the same chemicals do different things through different parts of our brain. To use just an easy example, we can't just modify or remove dopamine protein synthesis in cells and expect to fix something like schizophrenia. However, We would have to be able to express (genetically) that dopamine receptors in certain regions specifically need to be adapted or changed. And probably even more specific than that. But all in all, if 'we' can come out of the codes in a single cell, then I'm betting that how ever many codes are needed in order to specify one little operation, the codes Are in there. or maybe modifiable?
Name: hiro :)
Date: 2002-02-26 23:44:50
Link to this Comment: 1239
the same ideas can be applied to the academic grades. i was born and raised in japan, and when i was 15, i was thrown into a high school in california that had no ESL (english as second language) programs. of course, my first trimester grades were very low because i couldn't even understand what my teachers were saying or what the tests were asking me to do! (gosh, that was hard!!!) and it didn't mean that i was dumb. if i took the same subjects taught in japanese, my grades would have been a lot higher (of course, it might have depended on how much my teachers liked a trouble maker like me, too...).
Plomin & DeFries (1998) has mentioned dyslexia as if reading disability is a lack of intelligence, but i disagree. it is true that students with dyslexia have a very hard time academically. however, they show their "intelligence" in different fields. for example, i have a dyslexic friend who is a phenomenal basketball player. he has the most number of assists in his league because he can learn quickly about the playing styles of his teammates and opponents. and he gives different kinds of passes to different players, considering where his teammates are, who is playing well that day, where the opponent players are, what kind of rhythm the team needs at that time, etc, and makes the best decision in a very limited amount of time. although he may not be "smart" in the classrooms, i believe that his ability to succeed in basketball in such a way makes him an "intelligent" person, too.
if "intelligence" is realted to learning and memory as suggested in Tsien (2000), the amount of gray matter will not necessarily reflect one's intelligence. i agree that having more neurons increases the possible cell-to-cell connections. however, in order for the memory/learning to take place, the synaptic connections must strengthen. so, even if a child inherits some genes coded for producing a bigger gray matter, if he does not have an efficient amount of NMDA receptors or calcium transporters (which probably are also genetically determined), he will not be able learn or memorize quickly. on the other hand, if a person has a small gray matter but still has a very efficient NMDA system, he will be able to memorize and learn fast and be "intelligent".
people show "intelligence" in different areas, such as language, math, sports, music, art, etc. i believe that this phenomenon results from individual difference in brain structures. i think that one's brain has a highly developed memory/learning system in a certain area (like a part related to music or art abilities), causing the person to show "intelligence" in that particular field. and genes play an important role in determining which brain part(s) become highly developed.
Date: 2002-02-27 00:25:10
Link to this Comment: 1240
There are multiple factors that affect one’s intelligence; genetics is one of these factors. If we want to know what intelligence is, then it is necessary to determine how much influence each factor has on it. The most frequent statistic regarding the heritibility of intelligence is that genetics account for 50% of intelligence. The Wade article suggests a link between intelligence and the size of some regions of the brain that are under tight genetic control. However, it does not address what came first the size of the gray matter or the intelligence? This article leaves me unconvinced and seems reminiscent of phrenology. Though I found the Thompson article on the genetic influences on brain structure to be more convincing, it brought to mind the discussion on height that we had during the last class. Again, it seems that great variations can occur within families. This supports the idea that genes determine a range and where one falls within that range is under the influence of environmental factors. An important point that Plomin and DeFries make is that the collaborative genes that affect cognition do so in a probabilistic rather than deterministic manner. This parallels the idea of “the range” as well as Carey’s “indolent gatekeeper” analogy. I agree with Carey that IQ has the potential to open many doors, however, this not guaranteed, and the other factors such as motivation and interest have a great deal of influence on one’s success in life. I really like this quote by psychologist Robert Sternberg in response to The Bell Cure, “How strange that we have become a society that values what someone might do more than what he has done."
The study of the genetics of intelligence is not always desirable as it has the potential to lead to unfair assumptions and discriminatory behavior. Therefore, it is important to question the research that is being done. Hernstein and Murray, authors of The Bell Curve, led many to believe that immigrants would bring down the average IQ of our society and that measures should be taken to stop this. This differs from Tsien’s work on the NMDA receptors in Doogie mice that led to greater memory and long-term potentiation. Tsien’s work may have useful practical applications such as preventing cognitive decline while Hernstein and Murray’s work is based on numerous correlations and has questionable applications.
I have several uncertainties about the intelligence issue. Although I feel that there may be some beneficial results of research such as Tsien’s, I’m also weary of its potential use in genetic engineering. Inevitably,many will view this line of research as a means to increasing the general intellect of society. However, there is a need for people of varying IQs, each person serves a role in society appropriate to their intellect. In other words, how many rocket scientists does a society need?
Date: 2002-02-27 00:26:58
Link to this Comment: 1241
Date: 2002-02-27 00:52:59
Link to this Comment: 1242
|Intelligence and genetics|
Name: Mary Schli
Date: 2002-02-27 01:55:06
Link to this Comment: 1245
Exploration of the genetics of intelligence is useful because it can help us understand how to better educate our children (since the tests of intelligence seem to be measuring academic ability or even on a more basic level test taking ability) – if we understand what role genetics play then we can presumably also determine the role of the environment in the development of intelligence. However, I think that this exploration needs to proceed with caution, especially if certain genes are found to determine intelligence. This brings up the ethical issues that we discussed the first week of class about whether it is acceptable for people to screen for certain traits and to genetically determine their children. By exploring the genetics of intelligence, we open the door to numerous debates on this issue.
Based on the readings for this week, I think that the evidence indicates that there is a genetic influence on intelligence. The article on the Doogie Mice (cleverly named) was fascinating to me, and it seemed that the methods were carried out well. The whole idea that you can make a mouse learn/remember more by making its NMDA receptors contain more NR2B subunits was remarkable. In a way though it almost seems impossible that such a seemingly simple switch led to such a dramatic effect (but this has amazing implications for how we can improve learning/memory in humans). In contract to my feelings about this article, I did not agree with the Thompson et al. article. Although these researchers found some interesting results (that “brain structure was increasingly similar in subjects with increasing genetic affinity”) I don’t think that their conclusions were very valid. First, as I understood it, the researchers did not specify whether the twins in their study were reared by their biological parents or by adoptive ones, suggesting that they did not tease apart the effects of the environment in this equation. Furthermore, one cannot draw causal links from correlational data, and I felt that the authors were pushing their ideas a little too strongly in the causal direction.
One area in which I am uncertain about my answer is how to define intelligence more appropriately. While I think that it is important to consider intelligence as a concept, I do not think that we should judge people as intelligent or unintelligent based on their scores on IQ tests. However, I am not entirely sure at this point how I would scientifically define intelligence so that I could measure it reliably.
Date: 2002-02-27 01:57:27
Link to this Comment: 1246
Name: Caitlin Co
Date: 2002-02-27 04:31:40
Link to this Comment: 1248
And what of "multiple intelligences"? It's kind of a feel-good concept...everyone has intelligences, and is just as smart as everyone else, just in different areas...but does it make sense? The theory presumes that levels of each of the multiple intelligences are not strongly correlated with one another, which seems to contradict the idea of g. I kind of wonder if it was a theory established in order to take away the value judgment associated with g (that some people have more g than others, and more is better), which might be good, but if g is real, isn't really accurate. Which is not to say that talent, which is how I tend to think of factors like "musical intelligence" can't be just as important as g, just that if many of the intelligence"s" are strongly associated with one another we shouldn't ignore that.
I would also like to see more data on how g is associated with positive outcomes, other than high social status and income, which involve a lot of choice and are not necessarily all that positive. What about happiness and satisfaction? It seems to me, just anecdotally, that really high-g people are not the happiest people. Maybe there's a maximum, moderately high level of g that is associated with greatest happiness and satisfaction; but maybe it is noncognitive intelligence--practical intelligence and social intelligence--that is more important to happiness (which seems to be the ultimate measure of positive outcomes). If that is the case, why are we spending all this time on g?
Date: 2002-02-27 13:59:02
Link to this Comment: 1257
IQ however contains great construct validity and is reliable on almost all measures. It tests certain cognitive abilities that have been defined by test creators as measuring intelligence as related to expected school performance. This is not to say that poor standardized test takers cannot do well in school, just that it is an indicator of school performance. IQ test have been designed so that a score given at one point in life remains relatively constant over time. This is counterintuitive to what many believe which is that humans gain wisdom as they age. However IQ tests do measure what they say they measure and if a person does well on one type of test of cognitive ability they tend to do equally well on others.
When it comes to genetics, heritablity does play a large role, but it is surprising how little a role environment plays. I found it quite surprising that adopted children don?t resemble their adoptive parents on measures of verbal and spatial ability but birth mothers and these adopted children are just as similar as control children living with their birth parents, as of middle childhood. I would have hoped environment had had more effect. I find this especially worrisome because this might lead parents to downplay the effect of environment to the point where they place less of a role in educating their children.
|flowers for algernon?|
Name: Nirupama K
Date: 2002-02-27 17:11:02
Link to this Comment: 1263
"Intelligence" is at best a pretty ambiguous concept. There are of course IQ tests, standardized test scores, grades, and more subjective criteria like creativity. I suppose from a scientific/behavioral view a specific definition may be attributed to intelligence. Still the measure of it is always tricky. Because intelligence has such broad array of influences having one set definition runs into problems as well. From a cultural standpoint, different types of learning could be emphasized--making someone seem intelligent in one culture, but not intelligent in another. Ie, some cultures emphsize mathematical learning, while another highlights more linguistic aspects of learning. Even an IQ test, taken at face value may have little scientific value. The values are based on the relative scores of other people with 100 as the average. All of this makes any scientific evaluation of intelligence very muddled. We can measure how extra NMDA receptors make mice do better than their ordinary counterparts at certain tasks, but this demonstrates only one component of intelligence: memory. (I also just want to note the Flowers for Algernon feeling of that experiment...) It seems that it would be much more scientifically useful to use as specific of a term as possible when describing mental features. Intelligences implies too broad a spectrum of qualities to be useful in this way.
Given this relative uselessness of intelligence, I think that the exploration of genetic intelligence is going to be a fruitless search. One must acknowledge the multi-faceted nature of intelligence and recognize that there can be no direct genetic correlate to intelligence overall. I think that examing the many genetic factors which contribute to intelligence is much more helpful in our understanding of the mind and very desirable. By exploring the genetic components we can certainly learn more about the nervous system. There may be some perceived social impacts for the worse, but those should not even be considered here.
I think that the articles we read do point to individual components of intelligence which are genetic. I think that the twin studies conducted to measure intelligence are somewhat less useful and direct in their certainty of a correlation between intelligence and genetics because they didn't identify a specific component. I did find it interesting that they seemed to show how environment played a lesser role than genetics, but I still feel skeptical.
I am somewhat uncertain about my answers because I feel unsure about the definition of intelligence in general. I also am hesitant because I know that there are morphology differences which one can detect to compare the intelligence of two people. But, it is very hard to quantify these things into one objective standard. If such a standard where described to me I might change my stance. I think more genetic studies need to be done, not just statistical correlations between twins and adopted children.
|"Psychopathology" and "Personality"|
Name: Rebecca Ro
Date: 2002-03-18 12:58:11
Link to this Comment: 1500
To even begin to define personality is complex. There are many different approaches that can be taken when looking at the different perspectives of intelligence (for example: cognitive, behaviorist, humanist). By examining the relationship between personality and psychopathology you can see the relationship between certain personality dimensions and DSM diagnostic categories.
There can be no single gene that can define personality traits. Personality has to be influenced by multiple genes and various factors. For instance, environmental sources of variation in the environment are important. We know people's personality changes depending on what environment and situation they are in. Many people would act differently around a boss than they would act around their friends. Parental upbringing has to have some type of effect on personality.
The genetics of disorders have to do with both heritability and environmentability. To understand the psychopathology of disorders, one usually looks at family, MZ and DZ twins and adopted children. Mental illness can run in families, which shows that genetics plays a role. But genes do not determine everything. For example, sometimes one identical twin develops schizophrenia and the other twin doesn't. Therefore, influences other than genes probably are the reason. Schizophrenia looked at across different cultures could possibly show social and cultural influences. However, as the article on 'The Puzzle of Hypertension of African- Americans' said, pyschological and social stresses are extrememly difficult to measure, especially across cultures. "Identification of a gene associated with a greater susceptibility to a disorder is not equivalent to the cause of the condition." What influences a disorder is not always available for data. There are subtle differences in the brain which can make a big difference when discussing and understanding disorders. Understanding the brain is very complex. Even understanding the hereditary aspects of disorders is complicated. Stresses early in life can cause depression, however I don't see it as the only factor. Stressful life events and genetic factors probably both contribute to depression. But, how should you and do you treat those patients?Psychotherapeutically or pharmacologically? Drugs can have side effects. Should everyone be treated who has been exposed to a traumatic event? After the World Trade Center Attack, many people will not be emotionally the same again. How should we go about treating each individual; with therapy or drugs? What about people who feel they do not need any help?
Name: Huma Rana
Date: 2002-03-19 21:05:13
Link to this Comment: 1524
The relationship between personality and psychopathology is a difficult one to decipher. I would like to say that the two are on a continuum of behavior and that psychopathologies are characterized by extremes in personality. For instance a common personality trait is "being a ham" while an extreme form of this may be classified as a histrionic personality disorder by the DSM. It seems like some behaviors that transcend societal norms transition from personality flaws into psychopathologies. Although I like the idea of putting personality and psychopathology on a continuum, I'm uncertain about this because it is too simplistic and does a disservice to the mentally ill. It creates a problem by implying that the mentally ill could be "normal" if they somehow toned down their eccentricities. To me, it tends to put the focus on individual control or will rather than exploring the multitude of psychological-biological-social factors that can influence one's personality/psychopathology.
There is some influence of genes on personality and psychopathology. Studies on autism have showed that certain alleles (ex: HOXA 1) may be correlated with the disorder. However, it seems that most personality traits and mental illness are probably influenced by an assortment of genes. Also, it is important to acknowledge the role of the environment in all of this. For instance, the diathesis-stress models of depression, schizophrenia, and other psychopathologies are imperative in blending the roles of genes and environment. I'd have to agree with Carey, that once again, it is lemonade.
The exploration of the genetics of psychopathology and personality is extremely important and can immediately benefit society. I never fully grasped the importance of coming up with exact percentages regarding heritability of traits until reading the personal stories in the NIMH readings. These accounts conveyed the intense fear of not knowing if one's 2nd child will also have autism, or if otherwise normal kids will develop uncontrollable schizophrenia in their teens/early twenties. For people with family histories of mental illness, it would be helpful to know how much of a role genes play and whether or not they carry genes that cause certain susceptibilities. This knowledge will help people make an informed decision regarding reproduction, alleviate fears, and prepare them for what is to come.
It seems like certain areas of research have reached a plateau in what they can tell us about heritability and genetics. Family studies and MZ/DZ twin studies can only tell us so much and nothing can really be manipulated leaving countless confounds. Ideally, manipulating one portion of a gene at a time, cloning people, and raising them in the same exact environment (in a lab), and then testing their personality differences would answer my questions, but at this point, that is not legal, ethical or possible.
|Psychopathology vs personality|
Date: 2002-03-19 23:00:43
Link to this Comment: 1528
But then the line gets blurred when you start talking about personality disorders. This type of psychopathology is definetely part of a person's personality and stays with them throughout their lifetime. It is also more resistent to treatment. People in this category seem to have both a psychopathology and personality that is intermixed.
It seems to me that there is more of a genetic predisposition towards psychopathology then towards personality. I get this feeling simply because I have seen all the strong data pointing towards a genetic link with mental illness and have seen it in practice. But from personal experience I don't see a great deal of consistency of personality within the families I know. There is some, but it is not as strong as it is with psychopathology. Also as far as I have seen there has not been a great deal, if any data published on the biological basis for personality whereas every mental disorder has had at least some, if not a great deal published on the neurobiology of it.
Date: 2002-03-20 02:07:43
Link to this Comment: 1533
I think for our discussion it is better to use at least a more concrete idea of personality such as the reports of other people or the sum of our actions. The two terms are related in that Psychopathology can change our Personalities. As a person develops a disorder, changes may occur in their behavior. This behavior often can reveal the personality, or at least personality-tendencies, of the subject in quantifiable measures making it very useful.
The value of studying genetic behind psychopathology and personality I think is important but it cannot be the whole picture. Certainly in the depression article it was very apparent that the biochemical aspects were critical in our understanding of that disorder. With autism, a critical jump in research was made thanks to genetic research thanks to ingenuity with knockout mice. This was important because it lead researchers to identify a possible gene and variant alleles that could be found in human chromosome 7. Again this does not tell the whole picture but the genetic research is very helpful.
Although it is "helpful" (sorry for the vague term) there is a danger in how far we go with the knowledge we gain. Selecting for happy (as suggested in the fictitious article) kids for instance is not necessarily the best way to use our knowledge. I think that these are definitely dangerous areas where we may be getting involved in things we shouldn't take any part in.
|Psychopathology and Personality|
Name: Mary Schli
Date: 2002-03-20 02:11:11
Link to this Comment: 1534
Name: Julia Diep
Date: 2002-03-20 08:54:06
Link to this Comment: 1535
Personality is certainly complicated. It seems plastic in respect to influences in the environment, both chemical and social. When my brother or other friends with attention disorders talk about their experience taking ritalin or aderol they claim it changes their whole personality and don't like taking the drugs because of this despite the postive impact the drugs have on their grades. There also seem to be many examples of where the social environment influences or changes personality, over time, like abuse or even a job that's bearing and stressful, or just in one event like the world trade center bombing, or your baby being born.
Everything we are seems somehow related to genes, not always just what genes we have, but how and when they are expressed. I think most would agree that we have personality traits similar to our parents as much we don't like to admit it. Genetic influence on personality or psychopathology might be useful in someways as a starting off point, but definitely does not tell the whole picture how or why certain genes came to be expressed when and caused what changes that might possibly lead to personality. Basically it is all just lemonade, we have to be content with this mixture, and find other ways to explore treatments and explanations for psychpathology because there is no methodological way to separate the sweet lemony concoction back into its orginal ingredients. There's no rewind button on life why would we try to study it that way?
Name: Caitlin Co
Date: 2002-03-20 10:52:20
Link to this Comment: 1538
So to say something specific to personality and psychopathology and thus avoid just recycling last week's posting...the relationship between the two is difficult to understand and subject to societal constructions. With such disorders as depression, anxiety, etc., there seems clearly to be a continuum where being depressed or anxious at times is "normal" but somewhere along the line it is labeled as a "pathology". These cutoffs are necessarily arbitrary and might represent the point where functioning is significantly impaired (or the place where the person becomes significantly unpleasant to be around). With something like depression, with its various symptomology in different people and various personal histories, it seems that the genetic components are likely very complicated, a complication that is, I think, tied to its relation to personality...a period of sadness and disinterest for a generally cheery person might be distressing enough for that person to seek help for clinical depression, whereas the same state might not be far from "normal" for someone with a generally depressive outlook. When these symptoms represent a change from the usual state, they are a pathology; but they might be inherent facets of personality for some people. And since the genetic factors on personality are really complicated, those on psychopathology must be too. But then when you think of a disorder like schizophrenia, a continuum is not as evident...not so many people hallucinate just a little bit, and even if they did that would probably not be considered a "normal" degree of hallucination. That there is no normal here reflects to me the disorder's separation from personality...although colloquially we speak of people as having "schizophrenic personalities", I don't think that's really what happens...it's not just an extreme of a spectrum that has normal at its other end. Of course, when someone is experiencing severe symptoms of schizophrenia, the disorder tends to usurp whatever personality the person had before, so even here psychopathology and personality are related. For disorders like this one which seem more discrete and separate from general personality, I think I would be more likely to buy into a more simple genetic explanation, although the Carey chapter didn't. The stress-diathesis model regarding various psychopathologies is kind of appealing, and makes a good deal of sense for people who had traumatic childhoods, but with depression anyway, there are an awful lot of people who did not. Is their "predetermined threshold" so low that they will develop depression no matter what the circumstances? But in that case, it seems like non-trauma related depression would be more heritable...
Date: 2002-03-20 14:26:50
Link to this Comment: 1541
|luck of the draw|
Name: Nirupama K
Date: 2002-03-20 14:33:43
Link to this Comment: 1542
I am not sure if there is a specific relationship between psychopathology and personality, other than the fact that they are usually discussed under the domain of psychology instead of biology. Both are like many other traits with genetic diathesis influenced by the environment. Although, personality seems to be harder to pinpoint, because personality is not as easy to quantify. The lack of visibility of heritability may be casued by this vagueness, or simply indicative of the fact that personality is strongly influenced by outside factors.
I think that exploration of genetics in psychopathology and personality is extremely useful. If we don't understand the mechanisms they work with, then how can we claim to understand them at all? If we can pinpoint the genetics of these things we can deduce evolutionary clues from this information as to why they developed the way they did in the first place. Also, it is useful to keep in mind that we are still evolving.
Current observation does not provide real genetic diathesis for personality. The evidence for psychopathology is somewhat more solid, but also admits the influence of environment in the biological diathesis/stress models of disorder development. I found the MZ/DZ and adoption studies pretty compelling evidence for the heritability of certain disorders. Such studies, though, involving the different hypertension rates of blacks across the world detracted from the influence of genetics. It is clear that some traits are more heavily influenced by the environment than others. However, that study failed to show the genetic closeness of the different groups of blacks studied. There are many different ethnic groups in Africa itself, and this detail cannot be overlooked.
Name: hiro :)
Date: 2002-03-20 15:49:14
Link to this Comment: 1545
However, I also think that making distinction between personality and psychopathology is important in scientific studies because I feel that the genetic studies of psychopathology is far more helpful than those of personality. I do not think that genetic studies on personality is very useful since the environmental factors, which occurs by chance, can alter one's personality throughout their life. As long as the resulting personality does not prevent the person from living independently, there is nothing serious to worry about - at least, the person does not require medical attention. However, in case of psychopathology, such as autism or depression, the victim cannot live by himself. If genetic studies can discover the critical genes and ways to prevent such difficulties in one's life, the genetics of psychopathology will be very valuable. Of course, like personalities, psychopathology also depends on the environmental factors, so the genetics alone would not prevent every case of autism or depression. However, the studies may able to prevent some cases at least.
There are more reasons for whey I do not see importance in personality studies. Like in the fiction, maybe parents will be able to choose the personality of their children in the future. However, everyone already has different personality, and hence, the personality that may appear attractive to the parents may not be pleasing to others. Some people have personality that allows them to see positive characteristics in often neglected people (because of their pessimim or bad temper or whatever) and feel affections toward those socially unaccepted ones. Besides, personality is very complicated - it is not just the matter of being happy or sad, and genetic studies probably fails to come up with generalization of personality traits.
Althogh I have mentioned that personality development depends on environmental factors, too, genetic factors also may influence how someone's personality development is affected by environmental factors. Two people could grow up in the same environment and still could have very different personalities. I suspect that the difference in suceptibility to environmentally caused change in the brain structure (or the neurochemical systems) arises from the difference in the genetic make-up of the two people.
Now, this is unrelated to what I have discussed so far, but as I was reading "The Neurobiology of Depression", I came up with a question. The rats study showed that maternally deprived rats displayed signs of depression as adults. If these rats were given antidepressants as neonates (while being separated from their mothers), would they still show increased level of CRF concentrations in several areas of the brain in their adulthood?
Date: 2002-03-21 11:06:39
Link to this Comment: 1556
Next. I think the conversation went relatively well today, and though I'm sorry I missed responding to this earlier, I'm glad I got a chance to refine some of my beliefs through listening to the discussion.
I wanted to put up this link to a Jungian Personality test. Though there's a stigma that follows his name, and people don't find him so scientific. I feel that the expression of the 'science' (the gene influence of personality) is manifest in individuals in ways that are still hard to quantify and calculate. I think that this test and what it looks at are the key to personality. I like the distinction that we made today between Identity and Personality. I Do believe that personality is more stable and that they are more like things in How we interact with situations, not just What we do. I think the introvert/extrovert example is a very good one.
Here's the link. Though it doesn't seem so official it does have over 50 questions it calculates and does it in a relatively sophisticated way. It's quite similar to the 'official' tests. Though those are more fun to do.
Personally I'd be interested in finding out what everyone gets as an answer and if they're pleased with it. You don't have to share them, necessarily but it could be interesting. I'm an INTP. And I think that's pretty close to who I am. Not only that, but I took this in Highschool for a class (the official version) and I had the same thing, even back then. And I feel like I have changed as a person since then. At least Identity wise, but also on some general outlooks on life. Yet I still get this same score. That means a lot to me, and I feel that it is in concordance with my personal views on the topic.
|The Genetics of Sex, Gender, and Mate Preference|
Name: Rebecca Ro
Date: 2002-03-31 15:22:46
Link to this Comment: 1643
Dictionaries define 'gender' as basically the equivalent to sex. However, if you would look at the anthropological definition, it would most likely say that gender is a product of culture.
It makes sense that empirical evidence would indicate that females do prefer male traits that would most strongly stimulate their senses. Certain traits and qualities attract certain people. We have heard the saying that "sex sells". We learn about people's preferences in psychology and how certain people find other people attractive because they feel that they can obtain those people. However, I agree with the article on "How Females Choose Their Mates" which said that the benefits and costs of being choosing when selecting a mate differ for different species, in different environments and sometimes at different times of day. People tend to mature as they get older and what they look for in a mate may change. We know if we ask women what the top qualities they look for in a man and men what they look for in a woman, the answers usually differ. We know that some men want someone who is like their mother, while others do not.
Genes and the brain play an important role in human behavior. Science becomes especially hard when emotions are involved. Is your DNA really your destiny? There is complexity of links between genes and human behavior. Behavior in general is very complex. I agree that particular genes might influence personality traits that could in turn influence the relationships and subjective experiences that contribute to the social learning of sexual orientation. I think there are both biological and experiential factors that contribute to sexual orientation. We know that people can grow up in a household with two gay parents and not grow up gay. There probably is some kind of correlation between structure of the AC and sexual orientation, whether or not the size of the INAH 3 nucleus of the hypothalamus correlates as well. However, with LeVay's studies, the homosexual brains he sliced all came from men who had died of AIDS, therefore the cells could have been significantly affected by AIDS or the medication they might have been taking for it. Researchers can sometimes be confused as to what they are studying when they assess sexual orientation in their research. Did LeVay really know what sexual orientation those people really were? People can be one sexual orientation and act another for various reasons. There was not a range. He also did not include lesbians in his study and the sample size was not that large. Did LeVay's studies really prove that anyone was born gay? Are men gay because of a smaller INAH-3, or was their INAH-3 smaller because of the activities they engaged in, their thoughts, or their feelings? Our brains change in response to changes in behavior and the environment.
However, what exactly are all these studies trying to say? Doesn't everyone have a right do what they want with their bodies? There are many studies being done to try and find out what causes someone to be a homosexual. However, is society itself saying that there is something wrong with being gay? If a gay gene is found, would the nature/nurture question finally be answered? Is it genetic? Is it a choice? Is it neither?There was even studies about the size of your index finger and your sexual orientation. What would exactly be done if we did find scientific evidence?
I think the best evidence for a biological (would not necessarily be genetic) basis would come from animal studies. Most studies of the biology of homosexuality are based on the theory that almost everyone is either almost exclusively heterosexual or almost exclusively homosexual.What about being bisexual? Does that even exist according to science? One study can show a strong genetic factor in male homosexuality while other studies can show that identical twins are more likely to both be gay than non-identical twins. This just shows that the nature-nurture debate will likely continue for awhile. Also, another important thing to keep in mind is that genetic influence does not equal complete determinism.
Name: Huma Rana
Date: 2002-04-02 04:11:06
Link to this Comment: 1672
Like Rebecca, I feel that sex is chromosomally determined either XX or XY with some rare anomalies, but that gender is a social construct. Mate selection can be socially and genetically influenced, but the extent of each seems to be species-dependent. Although studies on guppies have showed that females can engage in rather complex discriminations between male guppies based on color preference, boldness and fitness, and social factors and imitation, it is unlikely that one could decipher similar patterns in female human beings. I do not deny that there may be a genetic or evolutionary draw to certain males, but this "chemistry" is hardly reason enough to pick a mate. I agree that factors such as education and socio-economic status override unconscious signals, but unlike Dr. Ober, I do not see this as a cause for high divorce rates. In fact, I think that making such a leap is somewhat ridiculous. Furthermore, I am not at all convinced by the arguments for MHC/HLA in modern-day mate selection. I would be willing to accept that MHC/odors may have played a role in mate choice pre-civilization (pre-showers and pre-deodorant), but not now. I did not find this to be a particularly valid line of research or one that is worth pursuing.
I do, however, find LeVay's research on the biology of sexual preference to be interesting. I agree with LeVay that this line of research should be carried out for the sake of knowledge rather than to gain social acceptance or to "fix" what some may perceive as being wrong. There is no denying the critical role that hormones play in the development of the brain, the SDN, and in mating behaviors in rodents. Also, LeVay's findings on the differences in the INAH 3 of heterosexual and homosexual men were notable, but do not imply any causation. This study probably raises more questions than it answers. LeVay failed to study many women, homosexual women, bisexuals, closeted gay men, or heterosexual men who had previous homosexual encounters. It seems that the boundaries of human sexuality and sexual preference may be too fuzzy to perform good scientific research on. Even if a genetic influence on sexual preference is found, I imagine that once again it will be "lemonade".
Date: 2002-04-02 19:50:52
Link to this Comment: 1686
In terms of sexual orientation, my opinion on all of the genetic research is basically contained in a brief paragraph at the end of LeVay & Hamer's 1994 article: "A second idea is that the hypothetical gene acts indirectly, through personality or temperament, rather than directly on sexual-object choice. For example, people who are genetically self-reliant might be more likely to acknowledge and act on same-sex feelings than are people who are dependent on the approval of others." In other words, there does seem to be some evidence that there is a genetic link to 'homosexuality' (i.e. the data on Xq28) However, as mentioned in other postings, I think that genetic research in general has a problem in that the level at which the effect is taking place is difficult to determine. Do the genes involved in 'homosexuality' lead to homosexual behavior? to same-sex attraction? to non-conformity/ antiauthoritarianism? At this point I don't think that we have the data to determine that.
As a side note, I was surprised to read the following in Byne's 1994 article: "Regardless of their genetic sex or the nature of their prenatal hormonal exposure, they usually become heterosexual with respect to the sex their parents raise them as, provided the sex assignment is made unambiguously before the age of three." Was this article published before the revelations about the blatant failure of John Money's Bruce/ Brenda/ David Reimer case? Although it's never a great idea to draw global conclusions from a case study, that case, combined with a great deal of other data about the effect of fetal androgens on sex-specific behavior in mice, for example, seems to me to blatantly contradict Byne's notion that gender in intersex babies is infinitely socially malleable.
Date: 2002-04-02 23:55:27
Link to this Comment: 1690
Date: 2002-04-03 00:54:29
Link to this Comment: 1691
|Sex, gender, and mate choice|
Name: Mary Schli
Date: 2002-04-03 02:03:00
Link to this Comment: 1693
I think that there is no clear cut answer in response to the question about the whether there is a genetic influence on sex, gender, and mate choice – although some of the articles stated that animal research seems to indicate a possible biological component in mate choice, I am not convinced that the methods employed in these studies necessarily apply to humans as well. Furthermore, several of the studies with humans suggesting a genetic influence on sexual orientation were twin studies, but these researchers failed to compare their data to twins reared apart (with the exception of one study with only 6 participants). The fact that these studies found higher concordance rates among the twins is not completely convincing of the genetic component involved and fails to examine the effects of the environment – perhaps monozygotic twins are treated more similarly than fraternal twins and thus the concordance rates for MZ twins was higher. Overall, given the articles, I suspect that there is a strong genetic influence on mate choice, but I remain uncertain about the validity of the animal data as applied to humans (consider the article that discussed how the sexual orientation of rats was determined). As I've stated, it also seems to me that some researchers have almost dismissed the possibility of the role of the environment in gender and mate choice, which seems problematic. I think that while we are certainly growing in our understanding of the influences on gender and mate choice, many more studies are required before we can feel that we have a complete understanding of these influences.
Date: 2002-04-03 02:15:48
Link to this Comment: 1694
Name: Caitlin Co
Date: 2002-04-03 02:56:31
Link to this Comment: 1695
I'm not so sure that gender is socially constructed any more so than sex is. To the extent that when children are born with ambigious genitalia and choices are made about whether to perform surgery and which sex the child should be, society is constructing a sex dichotomy just as much as a gender dichotomy. Most people identify as either males or females, although there is a whole range of masculinity/femininity within these groups. A few identify as somewhere in between...but that doesnt seem so different as how some are somewhere in between the male and female sex. Of course, society has determined what goes into the two gender roles, but as far as there being two, I don't think the societal component of gender is much greater than that of sex. Using a third dimension of masculinity and femininity, which has a more normal distribution, allows people to be either male or female in sex and gender, yet still have an identity falling anywhere on this continuum of masculine/feminine.
I am not terribly convinced by LeVay's data and the rest on biological influences on homosexuality, for all the reasons mentioned in other posts. I've always been intrigued by Bem's Exotic Becomes Erotic theory of homosexual identity formation, where boys who are less aggressive like to play "girl games" and thus associate with girls, thus viewing their own sex as the strange one, and attributing the heightened autonomic reaction to foreign stimuli as sexual attraction (I don't think he was concerned with same-sex attraction in women). I haven't heard much about this theory lately, so maybe it's been pretty much debunked, but I still like it...it seems to correspond to the trendy stress-diathesis explanations of various things. A genetic (or other) predisposition (diathesis) to lower aggression may or may not lead to homosexual identity formation, depending on how the environment reacts/encourages/discourages sex discordant behavior ("stress") and how strong the predisposition is...and it seems that could be a more direct genetic influence on aggression than on same-sex attraction or homosexual behavior.
Name: hiro :)
Date: 2002-04-03 11:31:59
Link to this Comment: 1698
although i find studies on the sexual orientation interesting, i do not see a point in identifying the cause of homosexuality. what do people do if they find out that homosexuality is genetic? or that homosexuality results from pre-adolescent experience? are the studies done so that they can find ways to prevent homosexuality by discovering the cause? i don't like that these scientific studies treat homosexuality as a disorder of some sort. whatever the cause is, i think it is more important that the society will accept homosexuals as one of many differences that individuals have. if the scientific studies can lead the society in such a way, i think they should be continued. but if they stimulate the existing discrimination against homosexuals, i don't think they should be done at all.
I thought I should share about a talk i went to earlier this semester because it relates to this week's topic a little. i can't remember the name of the lecturer or the title of the talk, but it was about social monogamy and sexual polygamy in birds. many birds are socially monogamous, but they actually mate with different partners! this observation came from one study that performed vasectonomy in birds - female birds became pregnant even though their partners had vasectonomy done. since the surgery was carefully performed, the females must have copulated with those males that did not get the surgery. although, having affairs is "wrong" in the human society, the lecturer discussed both positive and negative aspects of sexual polygamy. for males, the advantage seems clear. by mating with multiple females, males can spread more of their offsprings. For females, however, copulating with multiple males does not lead to a bigger number of offsprings because the number of eggs are limited. sexual polygamy seems disadvantageous in females because it increases the risk of STD infection, and if caught by their social monogamous partners, the females may be severly injured or killed by the male. but, there are adavantages, too. mating with different males assure fertility; if the actual partner is infertile, the female cannot produce offsprings without getting fertile sperms from other males. Also, it increases genetic diversity. Moreover, females may be able to receive "better genes" by mating with a cuter/wealthier male than their husband so that their offsprings will have a better chance of producing more and healthier offsprings. in spite of all the advantages of sexual polygamy, birds, like humans, stick to monogamy socially because both parents are needed to raise their offsprings.
do genes play a huge role in mate selection in humans? the study of HLA alleles suggest that they do. however, in humans, there are a lot of environmental factors that drives one's decision. i believe that smell is very important in attraction. but when it comes down to mate selection, humans think about more. personality, wealth, intelligence, family background, and so on. and i also think that mate seletion depends on one's experience with many people or events that affected one's personality development. since i don't think personality is not simply genetic, i think mate selection depends on more than genetics.
Date: 2002-04-03 23:09:05
Link to this Comment: 1707
|sex and stuff|
Name: Nirupama K
Date: 2002-04-04 00:27:15
Link to this Comment: 1710
The article on finches seems most appropriate to answer whether or not there is a relationship between sex, gender and mate choice. Mate choice may also be termed sexual orientation I believe. Sex is determined by genetics and physiology. I disagree that gender is a 'social construct'. I instead think that mate choice/sexual orientation is the real 'social construct' that is defined by intereactions with other individuals around you. Gender simply seems to refer to the morphological traits of sex. The way sexual traits are expressed does seem to be able to be controlled by hormone injection and living arrangement (which also influences hormonal levels, just ask any Mawrtyr). These both seemed to influence mate selection, though sex seemed to take over when placed in a colony environment. What does this mean? Gender and sex both play a role, but it is hard to transcend genetically assigned roles. Research on the differences between heterosexual and homosexual brains was very interesting, showing perhaps a unique difference in homosexual gender.
Sexuality is almost completely tied to natural selection in my mind. The entire point of sexuality is reproduction. Therefore, it seems only natural that we would study the genetics of this process. I think the exploration is very useful in understanding how evolution works and the basics of human behavior as well. Mate selection is a large issue for all of us, and understanding better what makes us do the things we do is beneficial for our self-knowledge. Considering that most literature centers on love and relationship, I think that biology should not ignore this field.
The genetic link to mate selection seems obvious, especially given the sort of selection cascade phenomenon. An individual chooses a mate not only because he has the most desirable characteristics, but also because her progeny will more easily find mates. Thus, desirable traits become entrenched. How else do we determine what is desirable than what are genes pre-dispose us for. There seems to be good evidence that humans are very drawn to certain MHC sites in smells, which correlate to their genes. Other factors, such as imitation play a role as well. But, genetic predisposition to colors for example rules the day when the differences are easily discernible.
Date: 2002-04-04 01:31:54
Link to this Comment: 1713
And just like, say, how we can not test certain aspects of language on some animals I don't think that animal studies on sexual orientation can completely explain the phenomenon. Le Vay's findings are intriguing but there are so many confounds. The disease itself, the fact that the difference could be consiquence not cause, etc.
I just feel like we are So far away from finding anything truly conclusive, if even insightful about the topic. The brain has yeilded few other secrets in other topics that have much more extensive research (the most hopeful I think would be memory). As for whether we should even research this and that controversy: I feel that we should research anything and everything. What we do with the knowledge is a question we should ask when we come to it. I think that's a basic benefit of free will-- choice rather than blind ignorance and inactivity.
Name: Nirupama K
Date: 2002-04-04 10:58:49
Link to this Comment: 1717
Name: Rebecca Ro
Date: 2002-04-15 16:11:55
Link to this Comment: 1814
Nature (genome) vs. nurture (environment) will always be a heated debate. To begin to understand both the genetic and environmental contributions in individual variations regarding human behavior is very difficult to do. There are definite obstacles in looking at genotype and behavior. It is hard to define a specific endpoint that characterizes a condition, be it personality, psychopathology, etc. How can we identify and exclude other possible causes? What about the social and political consequences that may be involved? When exactly does genetics play a role in understanding human behavior? When exactly does the environment play a role in understanding human behavior? When and how do genes more precisely affect human behavior? When and how does environment more precisely affect human behavior?
Genes and the environment interact with each other. Nature and nurture combine together to make each and everyone one of us unique individuals. The more and more we understand human behavior, the clearer it seems to me that nature and nurture are influences and certaintly not determinants. There is always unpredictability. How exactly do we factor in unpredictabilty? Even when we look at the environment in which the individual lives and the genome, we cannot account for all of behavior.
Each individual, I believe, has a way to influence their own life. There is the concept of 'self'. Nature and nurture only add to our understanding of who we are, how we develop, how we behave, and how we interact.
There is some evidence for genetic influences on various aspects of behavior. Our genes do somewhat influence who we are; both in how we develop and how we behave. However, genes alone cannot determine who we are. Genes can only contribute to one's individuality. The environment as well contributes to who we are. Individuals arise not only as a product of genetic makeup, but also because of environmental factors, as well as other outside factors. Sure, we may resemble our family members, but we are still our own individuals. Genes alone cannot determine our fate. We need a greater understanding of how the environment actually affects our genes. Behaviors involve multiple genes, which makes it hard to see which genes are the ones contributing to a certain type of behavior.
Is there some genetic basis for intelligence? I am sure there is. However, there are so many different genes that make up who we are. Genes are important when discussing and looking at the individual differences in intelligence level; however these influences cannot account for all of the variability. Of course, some of us have to work harder than others. Is intelligence influenced by hereditary factors when we are young, but then do we become more influenced by our environment later in life? All I know is that intelligence does come from our environment as well as our genetic makeup. How much is genetics and how much is environment is still in question.
There is evidence that many aspects of psychopathology are due to distortions of personality. Therefore, it would make sense to map genes for personality. I feel there is some type of intersection between genetics and the environments in mental illnesses. As far as family studies, I think they can answer the question if the disorder ran in the family, but they cannot answer the question if the disorder was actually caused by environment or genes. I think adoption studies are better in the aspect that they are better able to answer the question if the disorder was due to the genes or the environment. Twin studies can look at how much is due to environment and how much is due to genes. However, depending on the disorder there can be many genetic and environmental factors involved.
While there are specific genetic factors continue to be associated with alcoholism and other addictive behaviors, their exact contributions still remain unclear to me. Genes can trigger biochemical events in the body and interact with environmental and developmental influences. That in turn, can influence you behaving a certain way. However, genes alone cannot determine a person's future. Genes interact with each other, with the environment, and with the individual's response to these influences. Gene and behavior is not cause and effect. There can be no single gene for intelligence, behavior, and specific personality traits.
I think nature and nurture are both necessary for personality development. The home, outside, and culture, plays a role in personality. But we can we really 'measure' personality? It is obvious that we are different from each other, however why we are, still remains unclear to me. We 'shape' our personality depending on the situation.
Our behavior is influenced by genes, however our behavior is not determined by genes. For behavioral traits, we look at understanding the differences among individuals. Such differences may be caused by environmental factors and/or by one or many genes. I also think the concept of 'self' plays an important factor too.
Name: hiro :)
Date: 2002-04-17 00:03:46
Link to this Comment: 1853
Besides, what would scientists do if they found some genes that would cause generally undesirable personality traits, homosexuality/bisexuality, intelligence, and so on? People would be able to select desirable genes and eliminate undesirable ones to "create" a "perfect/ideal" person (or pet). However, as I mentioned above, even if an embryo/child has a set of "perfect" genes, the individual will not necessarily manifest all the planned phenotypes because of all the environmental factors that happens totally by chance.
Moreover, I believe that such preselection of human beings or any other animals is unethical. Rather than eliminating some seemingly unfavorable traits, people should spend more time looking for different solutions by improving the environmental factors so that the traits will be either fixed or incorporated into the environment as positive characteristics. Traits generally disliked are not necessarily negative all the time. For example, a person with manic disorder often shows magnificent talent in creativity. Contrarily, seemingly pleasant trait can be negative, depending on the situation. For example, in the fiction by Hamer (1999), the lesbian couple chose the genes for happiness for their future child; however, if the child is happy with everything she does, where does she get the drive to achieve higher when she performs poorly in anything? I strongly believe that people should focus on how to get the best out of what each individual happens to have instead of trying to prevent socially determined undesirable traits.
Although I have stated that I do not see a point in behavioral genetic studies, I do believe that the studies should be continued if, and only if, they help prevent severe and possibly life-threatening disorders. Like in the case of PKU, if the genetic studies help understand the pathway leading to the manifestation of the disorder, the studies will be very helpful in the treatment of the disorder. However, I question if all the disorders should be treated. For example, even though Williams people are mentally retarded, should they be treated when they display great abilities in music? And who makes the decision - scientists, parents, or the government? I also question if the gene information should be used to make decisions on abortions. And lastly, there would be a question on where to draw a line between disorders, personality, sexuality, and so on.
Date: 2002-04-17 00:42:22
Link to this Comment: 1854
When this course first began, I was one to scoff at the genetic influence on behavior. No, I didn't think that genetics was some mythical phenomenon that those crazy-science types believed in, I just had no desire to put much stock in it. In my ideal world, everyone is responsible for their own personality, intelligence, SES, and happiness with the exception of people suffering from huge abnormalities/deficits (ex: Down's syndrome). Slowly though, I became convinced of the role that genetics plays on all human behaviors.
Though many of the topics we discussed lacked any hard evidence, I think it is interesting that I most enjoyed Cosmides and Tooby's article on Evolutionary Psychology, the article with the least amount of quantitative evidence. I found this work to be the most logical and plausible of the articles we read. This nicely tied into the idea of modern day mutations such as tetrachromats, sweet receptors, and other human differences.
My epiphany began with the discussion on Williams syndrome which could be localized to a gene and resulted in consistent/predictable behaviors. Suddenly, it was not so hard to believe that musical, social, or verbal skills could all be produced by specific chromosomes. With this revelation came the possibility for all sorts of genetic effects on behavior. Soon intelligence, psychopathology, personality, sexuality, and mate preference also came under some genetic influence. Although I find some of these harder to accept than others, I'm not willing to completely disregard either nature or nurture as a component of any human behavior. Throughout this course, I have changed in that I regard human behavior to be multi-factorial, however, I have become more wary of assigning a percentage to how valuable each factor is to behavior.
Like Hiro, my greatest qualms with this class were the discussions regarding selecting for certain traits or the "designer-babies" dilemma. In general, I'm against selecting for athleticism, intelligence, looks, personality, but I have no problem with prenatally testing kids for Down's syndrome, PKU, autism, or schizophrenia. This dichotomy makes me feel like a hypocrite and I have trouble verbalizing why I feel that one behavior is acceptable while the other is quite deplorable.
Date: 2002-04-17 11:22:29
Link to this Comment: 1866
Date: 2002-04-17 14:47:58
Link to this Comment: 1868
Name: Mary Schli
Date: 2002-04-17 16:02:05
Link to this Comment: 1869
One theme that I felt since our first course meeting and continue to feel now is that we need to be cautious when exploring the field of genetics. As others have said, studying genetics can have tremendously rewarding results if we can eliminate many debilitating disorders. However, the situation becomes difficult when researchers search for and find genes for things like personality traits and intelligence. I think that almost all of us would agree that it is beneficial to prevent disorders such as Autism if we someday find the genetic components and have the technology to allow us to do so; however, when we begin to discuss the more gray areas such as personality traits, intelligence, and sexuality, there are likely to be infinitely many moral debates. Furthermore, a resounding theme in the articles over the weeks was that people may be discriminated against as a result of genetic selection of certain traits, which is something that I had not explicitly thought about prior to this course. However, I now realize the significance that some genetic studies carry and how the results from these studies may lead to unwarranted discrimination. Finally, while I agree that perhaps we should select for certain traits/behaviors, there are many that I feel we should never change since the natural variability in the population is what makes us all unique and able to be who we are and achieve our best.
|I WILL MISS OUR 8 AM BREAKFASTS...|
Date: 2002-04-17 21:56:48
Link to this Comment: 1871
In the discussions throughout the semester I feel there have been many conflicting ideas but no one seems to everaddress these disagreements. I think a lot of that at least for me stems from my inadequate articulation. I cannot express my points well enough and my ideas are too cloudy in my head. I find I rely too much on the readings as if they are the final authority. In reality I realized I need to be more rigorous in my evaluations. And if my intelligence proves to be inadequate that is ok. I do not have to have the answers, but I should have the intellectual curiosisty to seek others who are also interested in these topics and see if we can work through the idea. Maybe we won't be able to come to world saving conclusions but I may be able to figure out where I stand on issues and have firmer convictions. Moreover, I think when I am faced with studies that differ I can always go research more studies and see what the general stance that the literature takes. If that doesn't prove definitive then I can evaluate the studies to see which is more valid and/or talk through it with someone else. The best part about talking with other people about the issues raised in this class were that convictions that I did hold were challenged and I had to rethink them a bit...
Date: 2002-04-17 23:17:04
Link to this Comment: 1873
After that I found the class beneficial to me because it helped me put a bit more in the hands of environment. Not much, at least not comparatively. But I do understand how much of a role the environment can play. But I think that it is still impacting the brain rather than anything else. What does this do to free will? Well it somewhat confines it. If we begin at genetics and are somewhat manipulated by the environment, we are still the product of both and perhaps nothing else. I don't know why this is such a frightening thought to people. Our brains would then still be the causes and effects of all that has happened to us and still would be the organ within which there is the expression of the mysteries of humanity and all things human. I think fooling ourselves into thinking that the brain plays a lesser role is willfully remaining somewhat ignorant. There is so much to explore still and so much we don't understand. How could we possibly rule out the one place it would make sense for all these things to be?
I thought the topics that were discussed in this class were extremely interesting. Partially because they are things that we seem to care deeply about, and partially because the work so far is new and controversial. One problem I have though is the PC nature of this controversial quality. Why is it so bad to talk about some people as more intelligent? Why is it social stigma to find causes for homosexuality in the brain? When will we get over these aspects and just try to be scientists and do some wonderful research? Personally I don't see anything wrong with mapping out something that abolishes the vernacular term 'free will'. At least as far as it is literally defined. I still don't feel like the wonderful qualities of humanity will disappear simply because we learn something new about them.
I enjoyed this seminar class. I enjoyed the topic very much, and I enjoyed the people who participated in the discussion. One thing I wish we had not been caught up on so much is the details of perfect/imperfect procedures. Not so much that anything should be taken for granted or at face value but at least to be respected for it's ingenuity and best-shot. Testing methods are not perfect. None of them are, but with statistical analysis we try to obtain better data. And I think the minutiae of procedure often clouded or over shadowed are discussion of the topics at hand. Other than that, I think I learned a lot from this seminar. And if anything it was conducive to new levels of thought on some of the most intriguing topics of our time.
|I know nothing.|
Name: Nirupama K
Date: 2002-04-18 00:33:47
Link to this Comment: 1874
Still, I feel like this leaves me with very little. It's like what Plato said about knowing nothing. I don't feel wise though. I think it is interesting though how in our discussions we often turned away from talking about the experiments and data. We ended up relying on what we knew from personal experiences and feelings. This also makes me really question any conclusions I may try to draw from the class.
I think one of the major roadblocks which comes along with that type of thinking is the biases. All the issues we discuss become personal, and if we don't like the idea of personality being predetermined or permanent then we find someway to say that it isn't. Unfortunate as it may seem, the thought I keep returning to is that we have very little free choice. Our genes dictate so much beyond the basic framework. The subtleties within which may also control our motivation to change, etc. It may be a little fatalistic, but my biologist brain leads me down that path (!).
Name: Caitlin Co
Date: 2002-04-18 01:00:38
Link to this Comment: 1875
That being said, what exactly constitutes misuse of genetic knowledge? I'm honestly not as horrified by the idea of baby designing as others seem to be. It seems really shocking now to think about selecting for desirable physical or personality characteristics in an unborn child, but it's going to be a long and gradual process before babymaking becomes a game of mr. potato head. And we will have time to think about and adjust to the advances that bring about these possibilities, and figure out what we want to do with them. If parents feel that they are unable to raise a child with a particular disorder or pathology, I don't see anything wrong with selecting against it. And I know there is no logical place to draw a cutoff point anywhere on the line from that to selecting for eyecolor, but what is really so wrong with that? I'm not sure I think there's nothing wrong with it, but I'm also not sure exactly what IS wrong. But I think we'll be in a better position to deal with it when it starts happening. Again, I just don't think the future of genetic research is so ominous. Also, when you get into selecting for personality and such, of course you can't control your environment and you run the risk of parents being disappointed because the kid they end up with doesnt look like the one in the ad, but then again it gets back to the responsibility of the scientific community to make sure their findings get presented with the full story to go along with them--so parents need to be told that genes do not equal a guarantee. And don't plenty of us manage to disappoint our parents anyway?
|no more brains for breakfast|
Date: 2002-04-18 01:08:08
Link to this Comment: 1876
I, like the others in the class worry about the implications of genetic research. I am not sure if there even exists a safe place to draw the line. For all we know certain disease or disorders that are currently found to be disturbing might in the future have a place in society just as homosexuality was and to a large extent still is seen as undesirable. Obviously illnesses that cause suffering should be avoided but what about premature death? Two hundred years ago it was not unnatural for someone to die before age 40, at the rate medical technology is going it is not unthinkable that soon the average age of death will be a hundred, will we then say someone who dies at seventy died prematurely? I'm not sure there is a way to deal with genetic counseling and at the same time be totally PC or free from hypocrisy.
Along the lines of personality I am a firm believer that it remains constant barring any life-altering events set forth by the environment. This is not to say that the environment doesn't help to shape personality, just that personality- like many people is headstrong and resistant to change.
I would have to say the article that I found most interesting was the one on mate preference (How Females Choose Their Mates). However like Jimmy mentioned, I wonder how much confidence we should place in the hands of the authors given that twelve highly educated (soon to be) college graduate plus two well published professors have not been able (I won't use the word failed) to come to a consensus. For all we know they are arguing the same issues with their colleagues. This is especially true given that not all the articles were based on sound empirical evidence.
Overall I thoroughly enjoyed this class, frustrations and eight A.M. aside. It has given me and will continue to give me a great deal to contemplate, not to mention furthering my belief and appreciation for the biopsychosocial model.
Date: 2002-04-18 02:19:45
Link to this Comment: 1877
Name: Charles T.
Date: 2002-05-24 11:43:44
Link to this Comment: 2131
|Getting beyond A and B, to C, D, and beyond|
Name: Sandra J.
Date: 2003-04-19 14:26:49
Link to this Comment: 5443
|brain "lesions": dynamic or structural?|
Name: F. Frank L
Date: 2004-04-06 22:50:08
Link to this Comment: 9217
I've tried to make the case for fluctuating "non-structural lesions" via neuroimmune mechanisms as a basis for chronic symptoms after MHT (mild head trauma) in a series of presentations at Society for Neuroscience (and, with John Hasenkam, am scheduled for an update at the ASSBI/INS mtg in Brisbane this July).
One of the most striking examples of "dynamic" lesion is the pheomenon of alternating aphasias in bilinguals, as studied especially by Michel Paradis (Montreal: McGill, also UQAM).
A bilingual's French (for example) being more impaired than English (for example) early in post-stroke aphasia, but the reverse being true later (and still later, back to more aphasic in French than in English) simply cannot be understood as "lesions" in "French" vs. "English" language areas. Rather, dynamic competition between two co-mingled networks seems required (cf. lateral inhibition, center vs. surround, etc.?).
Paradis will be speaking on this, and I emphasise this aspect of the New York Neuropsychogy Group's 25th annual conference here, but in the "Diversity" section of serendip I've emphasised other aspects of bilingualism (q.v., or go to NYNG's website).
"Crosscultural Challenges to Neuropsychology's Brain Theories & Clinical Practice"
May 1, 2004, St. Vincent's Medical Center, Greenwich Village, NYC
[details at www.NYNG.org]
|brain "lesions": dynamic or structural?|
Name: F. Frank L
Date: 2004-04-06 23:01:23
Link to this Comment: 9221
I've tried to make the case for fluctuating "non-structural lesions" via neuroimmune mechanisms as a basis for chronic but variable symptoms after MHT (mild head trauma) in a series of presentations at Society for Neuroscience (and, with John Hasenkam, am scheduled for an update at the ASSBI/INS mtg in Brisbane this July).
One of the most striking examples of "dynamic" lesion is the pheomenon of alternating aphasias in bilinguals, as studied especially by Michel Paradis (Montreal: McGill, also UQAM).
A bilingual's French (for example) being more impaired than English (for example) early in post-stroke aphasia, but the reverse being true later (and still later, back to more aphasic in French than in English) simply cannot be understood as "lesions" in "French" vs. "English" language areas. Rather, dynamic competition between two co-mingled networks seems required (cf. lateral inhibition, center vs. surround, etc.?).
I emphasise this aspect of the New York Neuropsychogy Group's 25th annual conference here, but in the "Diversity" section of serendip I've emphasised other aspects of bilingualism (q.v., or go to NYNG's website).
"Crosscultural Challenges to Neuropsychology's Brain Theories & Clinical Practice" May 1, 2004, St. Vincent's Medical Center, Greenwich Village, NYC
[details at www.NYNG.org]