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Biology 202
2001 Third Web Report
On Serendip

Schizophrenia and the I-function: A Hypothesis Revised

Rachel Kahn

In my second web paper, I tried to come up with arguments supporting the hypothesis that schizophrenia was caused by an overactive I-function. Information about positive schizophrenic symptoms (distorted perceptions of reality, hallucinations, illusions, delusions, paranoia...)(2) suggested to me that the I-function of the schizophrenic was aware of things that the I-function of the non-schizophrenic wasn't. I also felt that because reality is such a biased, individual experience, non-schizophrenics do not have the right to label the reality of the schizophrenic as false. This hypothesis is flawed.

After doing more research and taking into consideration a suggestion from Professor Grobstein that maybe the problem is not an overactive I-function, but abnormal input to the I-function, I have reworked the hypothesis. One can still validly say that the reality of the schizophrenic is real. However, it is more accurate to emphasize that the reality of a schizophrenic is only real to the schizophrenic, just as each and every person's individual reality is actually only real to him or her. The difference between the realities of schizophrenics and the realities of non-schizophrenics is that for non-schizophrenics, information is processed in a more or less uniform way. That is, I interpret input pretty much the same way most people around me would. There are, of course, discrepancies in interpretations even between non-schizophrenics, hence the difficulty in relying on eye-witness accounts. For schizophrenics, though, the interpretation of input is completely different from everyone else around them due to the fact that the input is in some way wildly changed between the time it reaches the afferent nerve endings to the time that it ends up at the I-function.

I found that an excellent way to begin to understand how schizophrenia works is by reading personal accounts. Most of the accounts I found were written by people who, with the help of medication, were in recovery from schizophrenia. They give detailed descriptions of their lives and their thoughts before they recovered. What follows is an excerpt from "Maurizio's Story." Maurizio was in law school, had an active social life, and was in the top quarter of his class when he developed schizophrenia:

Within a few days in October 1976 all of this came to a crashing halt as I suddenly experienced my first psychosis. I can still remember those experiences vividly even now 18 years later. At first I thought I was coming down with the flu since the abnormal mental state I was experiencing was similar to the viral delirium of influenza but as I stayed in bed for a day my symptoms got even worse. I began to have delusions about the state of the world around me. Suddenly the noises made by cars and planes going by outside my house took on secret and deliberate meanings. I became convinced that I was involved in the start of a nuclear war and the only way for me to survive was to find the answer to a difficult riddle. During this first episode of psychosis I fluctuated between wild delusions of grandeur to deep depressions about my future. I thought I would become the next prime minister of Canada and rule by divine right over a new world order for our citizens. I was also visited by demonic voices. These grotesque distortions tormented me day and night until I could no longer distinguish between reality and nightmares.(1)

A close look at his story shows that in many instances, Maurizio received the same sensory input as those around him (the sounds of carsand planes) but these sounds became twisted as they were being processed. How were they being twisted? It is difficult to know, since despite the extensive amount of research that has been done, there is little conclusive evidence pointing toward any specific physical or chemical brain abnormalities that could be causing the symptoms of schizophrenia. In my last web paper, I wrote that because there haven't been significant abnormality findings through research on schizophrenics, the idea that the illness was caused by an overactive I-function was more likely to be valid. There are at least two problems with this statement.

The first problem has to do with the brain equals behavior theory. If one accepts that brain equals behavior, which basically says that all of our actions, thought processes, feelings, ideas, etc... can be traced back to the millions of neurons of our brains, then one finds a problem with the statement that abnormal behavior is not caused by an abnormality in the brain. Although I was skeptical throughout much of the course, I have finally accepted that the brain equals behavior theory is the best way to explain behavior, given the information that we have right now. Therefore, even if we don't know what it is yet, the abnormal behavior of schizophrenics is caused by some abnormality in their brains.

The second problem with my statement is that if schizophrenia were caused by an overactive I-function, we would still, in fact, expect to see evidence of an abnormality. Why? For much of this course, the I-function was a mysterious entity, not really something we could locate. However, toward the end of the course, we compared the electroencephalographs (EEG) of the brain during awake states to the EEG's of stage 1, 2, 3, 4 and REM (dream) sleep states. It seems very likely that the I-function has a location -- the neocortex. The EEG (which measures neuronal activity of the neocortex) of the awake state is strikingly similar to the EEG of REM sleep,(3) the only two states where the I-function is active. Therefore, if the abnormal behavior of the schizophrenic were caused by an abnormality of the I-function and thus an abnormality of the neocortex, we would expect to see evidence of this abnormality in research and possibly in EEG readings.

Although research has not yet pointed convincingly to one area of the brain as the source of schizophrenia, there are at least three main focuses of research at the moment, none of which directly implicates the neocortex as being a hotspot. One area of research involves the concentration of certain neurotransmitters in the brain. A chemical called N-acetylaspartate has been found to be reduced in some areas of the brains of schizophrenics.(4) Other neurotransmitters thought to be involved in causing schizophrenia are dopamine and glutamate.(5)

Another popular area of research has to do with enlarged ventricles. Ventricles are cavities in the brain's interior that are filled with fluid. Ventricle enlargement may indicate that the sizes of other brain regions are decreased. Another possible physical abnormality being researched is a difference in brain cell distribution between schizophrenics and non-schizophrenics.(5)

Aside from chemical and physical abnormalities, researchers are also looking in to whether or not prenatal viruses or other stressors could increase a person's susceptibility to schizophrenia. There is a great deal of uncertainty surrounding each area of research. In ventricle research, for example, researchers point out that ventricle enlargement is present in many non-schizophrenics, and many schizophrenics show no ventricle enlargement at all.(5)

Now that we have a bit of background on the types of investigations being done to determine the causes of schizophrenia, let's go back to the hypothesis that the I-function is not involved in the actual creation of the abnormal behavior, but simply receives information that has already beenabnormally processed. One common positive symptom of schizophrenia is a hallucination.(2 When we first started learning about the nervous system, we learned that output is influenced by sensory input. If the nervous system is thought of as a box, sensory input comes from outside the box, is interpreted and processed inside the box, and the output (behavior) reflects the processing of the input. We soon learned that output doesn't necessarily always arise as a result of input, but can reflect activity (thoughts, for example) that originated within the nervous system. The I-function can be thought of as a mediator, which is usually able to control the output.

The National Institute for Mental Health (NIMH) defines hallucinations as "perceptions that occur without connection to an appropriate source."(5) A hallucination can be thought of as sensory input that doesn't originate outside the nervous system, but rather inside the nervous system. The hallucination feels as though it is coming from outside the nervous system, for example a sound, or a sight. The I-function receives the information that there is a sensory input, and is unaware that there really isn't any stimulus. Because the I-function can't tell the difference between what is real and what isn't, it responds to both in the same way.

A similar phenomenon is an illusion. According to the NIMH, an illusion is "when a sensory stimulus is present but is incorrectly interpreted by the individual."(5) In Maurizio's story, the demonic voices that he heard would be considered a hallucination, and the abnormal interpretation of the noises from the cars and planes would be an illusion. His statement, "These grotesque distortions tormented me day and night until I could no longer distinguish between reality and nightmares,"(1) clearly indicates that his I-function is receiving abnormal input and is trying desperately to figure out what is going on, but simply can't.

Despite the fact that his I-function is confused and can't tell the difference between real and not real, Maurizio seems to maintain a sense that something is wrong throughout his psychosis. When the opposite is true, the schizophrenic is so fully engrossed in a reality that is not there that the I-function has essentially given up on trying to discriminate between real and not real. This is probably the state that most schizophrenics are in when they refuse to take medication. Most schizophrenics stop taking their medications at some point.(7) Consider the case of Doug, a thirty year old schizophrenic, whose story is told by his sister:

"Sometimes, late at night, my brother sits in his darkened room watching television without any sound and laughing hysterically. His giggling is punctuated by one-sided, incoherent conversations that he holds with the voices he hears in his head. Doug, like many other people who have schizophrenia, cannot or will not realize that something is wrong, and he refuses to take any medication. So for my family, it all becomes useless, all the groundbreaking research and fancy new drugs, because he will not help himself. Sometimes I want to just shake him and scream, "Don't you know? You don't have to be like this!" He is so lonely, so profoundly isolated from all that exists outside the cacophony in his skull. He has no friends, almost no human connection with anyone at all. He often imagines he smells horrible odors and sees vomit covering the television, his stereo, the carpet, his shoes. Conversations with him go like this: "Kansas, you know Kansas is actually in Dallas, because there is the road, and then you're in Texas and that's why Texas sports teams are so good. Never buy Campbell's. Chunky soup is really important. Never buy Campbell's."(6)

Because Doug is not unhappy, and because his I-function doesn't think anything is wrong, he can not be convinced to take his medication. His hallucinations of vomit covering his television are completely real to him. Statistics have shown that the sooner a schizophrenic starts medication after first developing symptoms, the more likely he or she is to recover.(4) This statistic makes a lot of sense, given that probably the I-function becomes less and less able to tell the difference between real and not real with each successive psychotic episode. Once the I-function thinks that everything is real, it also stops realizing that anything is wrong, and the patient sees no reason to continue taking medication. The patients forgets who he used to be and the life he used to live. A significant problem is that the medications available have fairly bad side effects, such as weight gain, depression, and muscle spasms. Patients who are aware of a problem and actively want to recover may be willing to put up with the side effects, while patients who see nothing wrong would obviously see no reason to put up with unpleasant side effects from a medication they see no point in taking.

One percent of the population, worldwide, has schizophrenia. That is twice the number of people who suffer from Alzheimer's disease and six times the number of people that suffer from type 1 diabetes.(7) Although recent medications have side effects, they are much less severe than the side effects of the first medications, which didn't work very well, and only produced an antipsychotic effect because they were essentially tranquilizers.(7) Most likely the newer medications are aimed at compensating for the specific abnormality causing the behavioral output, while the older medications simply worked to lessen all behavioral output. In other words, the new medication is taking effect before the abnormal input reaches the I-function, while the old medication effect took place after the I-function received the information. In any case, it is a very worthwhile task to try to understand as much as we can about what is going on in the brain of a schizophrenic. Not only will we be better equipped to provide treatments and cures to the many people who have schizophrenia, but I imagine that an understanding of schizophrenia will lead to an understanding of many other mental illnesses.

WWW Sources

1)Maurizio Baldini's story, Maurizio's story (how he dealt with and is still dealing with schizophrenia.

2)Schizophrenia Diagnosis, Description of symptoms of schizophrenia.

3)Sleep Syllabus,A comparison of EEG recordings for awake state and sleep state, including REM sleep

4)NIMH - Schizophrenia: Understanding It, Treating It, Living With It. 5)Schizophrenia, A lot of good info about schizophrenia.

6)My Brother, Doug's story, told by his sister.

7)The Experience of Schizophrenia,A page about schizophrenia created by a man with schizophrenia.




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