Mignot is one of this country's leading researchers in Kleine-Levin Syndrome (KLS), a rare neurological disorder that affects primarily male adolescents. Those afflicted experience periods of excessive sleep (up to 20 hours a day), and, when awake, experience altered behavior. Parents of teenagers might argue that excessive sleep and altered behavior are teen trademarks, badges of teenage-dom - hardly rare! With KLS, however, sleep episodes can last a few days to a few weeks.
At the onset of an episode the patient may experience flu-like symptoms, become drowsy and sleep for most of the day and night, waking only to eat - sometimes excessively - or go to the bathroom. When awake, the patient may appear spacey, irritable, childish, apathetic and disoriented. Instances of uninhibited hypersexuality during an episode have also been noted. KLS usually lasts 8 to 12 years, and episodes gradually become less frequent and less intense as it runs its course.
There is no definitive treatment and the cause of KLS is unknown. But Mignot and his group have launched multiple studies to uncover the underlying causes and, hopefully, find an effective treatment.