Biology 202
1998 Third Web Reports
On Serendip

Tourette Syndrome

Christy Taylor

I have been intrigued by this disorder since I met a beautiful little girl named Sarah. Sarah's father recently told me that doctors have informed him that Sarah may have Tourette Syndrome. I had visions in my mind of a little girl shouting profanity uncontrollably with arms flailing about, although the times that I have been with Sarah have never been marked by these actions. I set out to find more information to satisfy my own curiosity and to make myself a resource for Sarah's father. Tourette Syndrome (TS) was first officially described over 100 years ago by a French neurologist named Gilles de la Tourette, a pupil of Charcot's and a friend of Freud's. He described nine patients, primarily Madame de Dampierre, by saying: At the age of 7 (she) was afflicted by convulsive movements of the hands and arms. . . She was felt to be suffering from overexcitement and mischief, and . . . she was subjected to reprimand and punishment. It soon became clear that these movements were indeed involuntary. . . involved the shoulders, the neck, and the face, and resulted in contortions and extraordinary grimaces (1). Soon after the motor tics developed, Dampierre developed vocal tics consisting of screams and cries. Until her death at 85, she was forced to live in seclusion (2). Between 1920 and 1960, TS was all but forgotten, and psychiatrists and psychoanalysts treated the symptoms as suppressed aggression, which proved ineffective (1). When drugs such as haloperidol were able to alleviate symptoms in the 1960's, however, Giles de la Tourette's initial observations were reevaluated. Dr. Oliver Sacks notes, "Tourette's was regarded - in a sudden reversal - as a chemical disease, the result of a neurotransmitter, dopamine, in the brain" (3). Research on the disease has seen a dramatic increase since the eighties, and focus is centered on its roots in biology and neurology, rather than on the possible psychology (1). TS is presently classified as a "neurological movement disorder." To be officially diagnosed with TS, a person must demonstrate multiple motor and one or more vocal tics throughout a span of one year. The tics may occur with varying number, frequency, type, location, and severity. Tics increase as a result of tension, stress or sleep deprivation, and decrease or even subside when sleeping, relaxing, or concentrating on an absorbing or complicated task (4). The onset is before the age of 21 with motor tics appearing, on average around the age of seven, and vocal tics at age nine. The symptoms usually intensify during adolescence, but usually grow less severe during adulthood (4). Once thought to be rare, TS is now recognized as relatively common, affecting up to one person in every 2500 (5). Although TS affects all races, it is four times more common in males than in females, and is therefore considered a genetically inherited disease following an autosomal dominant pattern. A person with TS has about a 50% chance of passing the gene to their children with each pregnancy although, according to the Tourette Syndrome Association, "the genetic predisposition may express itself as TS, as a milder tic disorder, or as obsessive compulsive symptoms with no tics at all" (6). Thus, 31% of people who carry the gene may not be aware of its presence, but can still pass the gene on to their children (8). Tics can be divided into two categories: motor and vocal. Motor tics can be simple or complex in appearance and often recur in the same part of the body. Motor tics usually migrate from one region to another over time. Examples of simple motor tics include: eye blinking, eye rolling, shoulder shrugs, head jerks, facial grimacing, dart of the eyes, lip smacking, tongue thrusting, mouth opening, leg jerking, and arm flexing or flapping. Simple motor tics are often repetitive, such as a repetition of eye blinks, or a repetition of lip smacks. According to the Tourette Syndrome Classification Study Group, "complex tics are distinct, coordinated patterns of sequential movements. They may appear purposeful, as if performing a voluntary motor act" (7). Examples of complex tics include touching the nose, touching other people, smelling objects, hitting self or others, clapping, pinching, squatting, skipping, somersaulting, stooping, hopping, kicking, throwing, deep knee bending, foot tapping, foot shaking, pulling at clothes, and scratching (4). Several tics have their own classifications, such as echopraxia, the urge to mimic others' actions, and copropraxia, the urge to make obscene gestures (7). Vocal tics are characterized by a variety of involuntary sounds made by moving air through the nose, mouth, or throat. Examples of simple vocal tics include: throat clearing, grunts, snorts, sniffs, squeaking, coughs, humming, screams, spitting, puffing, sucking, stammering or stuttering, hissing, laughing, shouting, barking, moaning, squealing, clicking and clacking (4). Complex vocal tics are composed of understandable words or phrases and may include echolalia, the desire to repeat other's words; palilalia, the urge to repeat one's own words or thoughts; and coprolalia, or swearing. Because of media influences, coprolalia is perhaps the best known and dramatic aspect of TS. Pieter Nagel, a TS sufferer, puts this aspect in perspective when he says, "The truth is that swearing is not a universal symptom of TS. Coprolalia occurs in about eight to 30 percent of cases, and even then it often seems to last only for a phase in life" (1). According to the Spring 1996 edition of the National Tourette Syndrome Association's Newsletter, much research has been done to study tics. This research was spurred by the work of Joseph Bliss, who himself suffered from TS. Bliss succeeded in drawing the attention of the medical community when he summarized his own personal battle with tics and the sequence of events that lead to them: There is really no adequate description of the sensations that signal the onset of the actions. The first one seems irresistible, calling for an almost inevitable response. . . Intense concentration on the site can, in itself, precipitate the action. . . TS movements are intentional body movements. . . The end of a TS action is the "feel" at the terminal site of the movement, a "feel" that is frequently accompanied by a feeling and incomplete sense of relief. A need to tic is an intense feeling that unless I tic or twitch, I feel as if I am going to burst. Unless I can physically tic, all of my mental thoughts center on ticcing until I am able to let it out. It is a terrible urge that must be satisfied (9). It is interesting to note, however, that young children who have simple tics may not have, or may be completely unaware of, the sensory urges described by Bliss. For them, TS may truly be an involuntary disorder. However, urges usually begin about three years after the first onset of tics, and studies indicate that 90% of all persons surveyed experience urges before their tics. At the same time, however, urges are less severe for more autonomic behaviors, such as eye blinking (9). While the word "involuntary" is often used to describe the nature of tics, this is not a completely accurate description. As Bliss described above, persons with TS have some control over their tics, often being able to hold back their tics, consciously or unconsciously, for hours at a time. Tics are usually lowered or non-existent during sleep, intense concentration, or times of relaxation. However, for a person with continual tics, efforts to suppress them can only last for a short time and are usually followed by uncontrollable bursts of rapid-fire symptoms as soon as the person allows them to occur, usually in private places or around those with whom they feel comfortable (10). In his book, A Surgeon's Life, Oliver Sacks, M.D. describes time spent with Dr. Carl Bennett, a surgeon in Canada. Afflicted with TS, Bennett contends with motor and verbal tics, often quite severe, but his symptoms completely subside during his surgery, unless interrupted. Sacks writes, "The preliminaries (before surgery) over, Bennett got down to the serious work, swabbing the buttock with an iodine antiseptic and then injecting a local anesthetic, with an absolutely steady hand. But as soon as the rhythm of action was broken for a moment - he needed more local, and the nurse held out the vial for him to refill his syringe - there was once again the darting and near-touching" (3, italics mine). Physicians and scientists continue to debate where in the brain tics come from and the biological cause of Tourette Syndrome. Most research focuses on the basal ganglia as a likely site of pathology in TS because of its similarities to other involuntary movement disorders such as Huntington's Disease and Parkinson's Disease. The latest understanding of the disorder is based on autopsies performed on Tourette sufferers revealing an imbalance of brain chemicals and lack of development in one particular section of the brain. The Weizmann Institute of Science states, "In a normal, right-handed adult, the left side of the brain was enlarged, but in a right-handed Tourette sufferer, it was not, resembling the brain of a one-year-old child" (11). Another recent and interesting study explored the differences in the severity of tics between monozygotic twins with the disorder. Using a SPECT scanner that employs radiation detectors to get a fix on the location in the brain of a tracer drug, researchers were able to image dopamine binding action in five sets of identical twins to yield fascinating results. The team discovered that for each pair, the head of the caudate nucleus showed much more binding of the neurotransmitter dopamine (D2), in the more severely affected twin. Based on these findings, the team was able to correlate a greater degree of dopamine binding with increasing severity of TS symptoms (12). Also interesting is the role the environment may play in TS severity. A study conducted by NIH on twin pairs found that the affected twin consistently had lower birth weight than the unaffected twin did. Another study found that in 12 of 13 pairs of MZ twins differing in birth weight, the twin with the lower birth rate had more severe tics (2). This may further implicate the role of the caudate nucleus because this area of the brain is highly vulnerable to prenatal and perinatal injury. Overall, the data from the twin studies provides a unique relationship between the environment (probably neurodevelopmental) and genetic predisposition. While persuasive, the neurological findings may not offer a total explanation. I am inclined to agree with Oliver Sacks, M.D. when he states that biological justifications for the disease are "partial, reductive and fail to do justice to the full complexity of Tourette's which may be almost as complex as human nature itself. the relation of disease and self, 'it' and 'I' can be particularly complex in Tourette's, especially if it has been present from early childhood, growing up with the self, intertwining itself in every possible way" (3). Therefore, Tourette's must be described as a biopsychosocial disorder to encompass its complexity. So how is the psyche involved with TS? I postulate that the I-function is not a part of the symptoms seen in TS. The tics are coming out of the nervous system without the I-function of the afflicted person being causally related to them. While the I-function is not capable of causing or absolutely controlling the tics, it can influence the tics for a time, thereby explaining the temporary conscious control of tics. However, as mentioned above, the tics come back with fuller force after this period of controlled inhibition. One question that I pose to myself is why children that first exhibit the symptoms of TS do not have the premonitory urges that Bliss described. I reconcile the role that the I-function plays by thinking that one function of the I-function is to make sense of what is going on in the body. Early on in childhood, these sensations are novel activities out of the neocortex and nervous system and the I-function may not know how to interpret this information yet. But in time, this does occur. It is also interesting to note that tics can be unconsciously controlled. For instance, Bennett was not consciously telling himself during his five and six-hour surgeries that he needed to inhibit his ticcing, it occurred naturally. Therefore, there must be a difference between the ability to concentrate on controlling the tics as well as the ability have the tics subside when concentrating on something else. When the I-function is focusing on tics to control them, it does so through active inhibition. However, when the I-function is concentrating on something else, there may be a change in the general control mechanism, which may be lessened or inhibited, thereby also inhibiting the ticcing movements. This may also be the reason that no tics are seen during sleep. Researchers may also find valuable cues to controlling tics by understanding the relationship between the diminished general control mechanisms and the diminished ticcing behaviors. In conclusion, Tourette Syndrome is remarkably complicated. It envelops so much of the person that it is hard to separate. What is abnormal and what is simply personality? It may be arrogant for researchers to automatically assume that persons with tics and TS want to be "cured." Bennett describes his ticcing behaviors as "something that has come to be part of himself" (3). Sacks sums this up nicely when he states: The Tourette's and the self shape themselves each to the other, come more and more to complement each other, until finally, like a long married couple, they become a single compound being. This relation is often destructive, but it can also be constructive, can add speed and spontaneity, and a capacity for unusual and sometimes startling performance. For all its intrusiveness, Tourette's may be used creatively, too (3). Half the battle with Tourette Syndrome may be awareness of the disease and a renewed perspective about it. The next time that I see Sarah I will not expect to see a little girl with flailing arms shouting obscenities. Instead I will most likely forget that she has TS at all, if only I keep an open and accepting mind.

References

1. The Tourette Syndrome Frequently Asked Questions. Nagel, Pieter.

2. Tourette Syndrome: A Model Neuropsychiatric Disorder. Weinberger, Daniel R., and Thomas M. Hyde.

3. A Neurologist's Notebook from A Surgeon's Life Sacks M.D., Oliver.

4. The Virtual Hospital: The University of Iowa Department of Psychiatry and the Tourette Syndrome. Association, Inc.

5. Tourette Syndrome: Information on Benefit Coverage.

6. Questions and Answers about Tourette Syndrome.

7. Definitions and Classification of Tic Disorders. The Tourette Syndrome Classification Study Group.

8. Personal Health: Living with the Mysteries of Tourette Syndrome. Brody, Jane E. The New York Times, March 1, 1995.

9. An Early Warning for Tics?: Faint Signals, Sensory Urges, and Momentary Relief. Leckman Ph.D., James F. National TSA Newsletter - Spring 1996.

10. The Facts about Tourette Syndrome. Alternative Health.

11. Scientists Brainstorm to Find Cure for Tourette Syndrome. Weizmann Institute of Science.


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