Neuroimaging findings in narcolepsy with cataplexy

Various brain imaging techniques have been used to study narcolepsy with cataplexy. Anatomical data with magnetic resonance imaging have characterized specific alterations in grey and white matter and their potential implications on disease severity. Functional neuroimaging studies have described changes in brain perfusion or glucose metabolism during resting wakefulness, as well as brain responses to emotional stimulation in narcoleptic patients. These different imaging modalities provide evidence for structural and functional abnormalities compatible with a deficit in the hypocretinergic system. They also indicate the involvement of other neural structures, such as the amygdala, nucleus accumbens, midbrain, thalamus, hippocampus, and fronto-temporal cortical areas. This article reviews the contribution of neuroimaging to the pathophysiology of narcolepsy with cataplexy, focusing on the most recent developments.