Tourette's is a condition of the central nervous system that causes tics - twitches, movements or noises that are repeated over and over. Researchers believe that two chemicals found in the brain, dopamine and serotonin, may play a role in its onset. And researchers believe the syndrome to be genetic in origin.
It is very much a childhood disorder, with onset between the ages of 2 and 15 and commonly around age 6 or 7. It is more common in boys than girls. And though it may subside, it is a lifelong condition. (Former Phillies outfielder Jim Eisenreich has it.) One more point - about a third of those diagnosed with Tourette's syndrome also have related difficulties: attention deficit hyperactivity disorder, obsessive-compulsive disorder, or learning disabilities.
Tourette's is an uncommon affliction - estimates vary, but an often-cited figure is that one in 2,000 people is affected.
The tics and odd behavior associated with Tourette's - in more serious cases the behavior can include obscene language or sexual gestures - can mark a child as "weird" to classmates or disruptive to school officials.
"It's a very, very difficult situation," said Michael Moskalski, superintendent of the Jenkintown schools and past president of the Pennsylvania Tourette Syndrome Association. Moskalski's daughter, now grown, was diagnosed with Tourette's as a child - among her symptoms was a tic that involved repeatedly clearing her throat.
"Tourette students have physical tics and verbal tics that can be irritating in school, and things that we don't normally allow," he said. "How do you be fair to that child with Tourette's? And how do you be fair to the rest of the class?"
The stress and anxiety experienced by the child can be overwhelming, and it builds as he or she attempts to control or conceal the tic. But Tourette's is a condition that to a great extent is beyond the child's control.