Functional Neuroimaging of Sleep and Sleep Disorders
Functional brain imaging studies have reported the neural network activities associated with the different stages of sleep. Recent functional MRI studies have more precisely characterized the neural correlates of sleep microarchitecture, composed of specific brain oscillations such as spindles and slow waves. Beside the identification of brain areas involved in the generation of these waves, these studies have shown that sleep is a state of intense and phasic neural activity organized by thalamo-cortical rhythms. These reports have demonstrated that brain rhythms not only shape the activity of brain structures during sleep, but also profoundly affect the neural responses to external stimulation during sleep. On the other hand, functional neuroimaging contributes to elucidate the pathophysiology of sleep disorders. Recent studies have also shown the potential of these methods for the diagnosis and prognostic evaluation of sleep disorders such as parasomnia.