The Ticcing Link: Many Mental Disorders and a Few Crucial Genes May Tie into Tourette's Syndrome
Bower, Bruce, Science News
The Ticcing Link
In 1902, a Frenchman identified only as "O." bared his soul in print under the title "Les Confessions d'un Ticquer." As a boy, O. wrote, he had felt the urge to imitate any curious gesture, facial expression, phrase or pronunciation he observed in others. In private, he practiced each imitation over and over; in public, the well-rehearsed "tics" would involuntarily reappear for months thereafter.
O. soon developed numerous other vocal and body tics, often driven by irrational, irresistible thoughts. For example, as soon as he placed his pince-nez on his nose, he felt compelled to continually readjust its position, occasionally jerking back his head for a better focus. His gaze wandered back and forth, from the rim of the pince-nez to whatever he was looking at, and he felt uncomfortable when either was not in his line of sight.
"My tics upset my pince-nez, and I have to invent another tic to get it back into place," O. lamented. "The absurdity of this vicious circle does not escape my observation, and I know I am its author, yet that cannot prevent my becoming its victim."
O.'s confession also included the comments of his two physicians. They noted that he consciously suppressed his many tics for an hour or two in the company of others. When the pressure to tic became too great, O. would retreat to an empty room, they wrote, "abandoning himself in his moment of solitude to a veritable debauch of absurd gesticulations, a wild muscular carnival, from which he returns comforted, to resume sedately the thread of the interrupted dialogue."
O.'s strange condition is known as Tourette's syndrome (TS), and it is hardly a turn-of-the-century relic. Although modern clinical descriptions of TS are rarely as penetrating as O.'s confessions, TS today affects a surprisingly large number of people--perhaps 100,000 to 330,000 in the United States alone -- and currently receives the close attention of several research teams. Some of those scientists, at last May's meeting of the American Psychiatric Association in New York City, described their efforts to uncover the genetic foundation of TS and decipher the connection of multiple tics to a number of psychiatric disorders and behavior problems.
One research team even proposes that TS is linked to one or a few genes responsible for many impulsive, compulsive, learning and mood disorders. Others contend that the close study of TS will nudge neurologists and psychiatrists toward a much-needed reconsideration of how brain, mind and body interact.
Despite these hopes, TS remains poorly understood and is often stigmatized. Its most infamous feature is the compulsive blurting out of obscenities, but this symptom occurs in only about one-third of TS sufferers and is not a requirement for diagnosis. The syndrome's cardinal signs are motor and vocal tics appearing almost daily for at least a year, beginning before age 21. All manner of jerks, grimaces, noises, imitations and compulsions may occur.
For instance, some Touretters are impelled to court danger by holding their
hands as close as possible to open flames or spinning objects such as fans.
As the tide of nervous energy rises, thoughts and mental associations typically become more frenzied. A rapid and tenuously connected stream of ideas pours forth, at times expressed in creative and amusing ways.
TS symptoms wax and wane in the course of a day, and as O. demonstrated, Touretters can control them to some degree. The disorder strikes three to four times as many males as females.
"Most cases of Tourette's syndrome are mild and don't come to medical attention," says neurologist Roger M. Kurlan of the University of Rochester (N.Y.). Kurlan, who has studied nearly 200 members of an extended Canadian family with many TS cases, estimates that one in 2,500 people suffers full-blown Tourette's and one in 700 has a milder form of the disorder. …