Kleine-Levin Syndrome: A review

Abstract

Kleine-Levin syndrome (KLS) is a rare disorder characterized by (PERIODIC hypersomnia) associated with behavioural disturbances such as binge eating (hyperphagia), irritability, and increased sexual interest (hyper sexuality). Episodes are separated by weeks or months of normal sleep and behaviour. Between episodes, patients have normal sleep, mood and behaviour. Previous finding of reduced working memory capacity in Kleine Levin Syndrome. This deficit correlates to lower activation of the anterior cingulate cortex and adjacent dorsomedial prefrontal cortex and stronger activation in the medial and anterior thalamus and possibly the inferior frontal gyrus. Thalamic activation is also amplified in sleep deprivation, especially when participants remain alert. Thus, increased thalamic reactivity could also represent a compensatory response: through recruitment of thalamic networks, the brain is trying to compensate for increasing processing demands invoked by disturbed sleep or attenuated wakefulness.