Chronic insomnia disorder: perspectives from structural neuroimaging

Chronic insomnia disorder is the most widely reported clinical condition in medicine. It has a significant impact on populations and is characterized by chronically disturbed sleep and sleep loss, non-refreshing sleep, and heightened arousal in bed. Poor sleep is associated with a wide range of negative health outcomes, and it is reported that poorer quality of life and medical, neurological, and psychiatric comorbidities disrupt sleep. Sleep difficulties may result from multiple etiologies; however, the neurobiological mechanisms underlying chronic insomnia disorder are not sufficiently understood. Recently, numerous neuroimaging studies have been conducted to investigate the structural or functional derangement in the brains of patients with chronic insomnia disorder. The development of neuroimaging techniques has provided insight into the pathophysiological mechanisms that make patients with chronic sleep disturbances vulnerable to cognitive impairment.