Functional Neuroimaging Evidence for Hyperarousal in Insomnia

• Published in: The American journal of psychiatry Vol. 161; no. 11; pp. 2126 - 2128
• Main Authors: Nofzinger, Eric A., Buysse, Daniel J., Germain, Anne, Price, Julie C., Miewald, Jean M., Kupfer, David J.
• Format: Journal Article
• Language: English
• Published: Washington, DC American Psychiatric Publishing 01.11.2004; American Psychiatric Association
• Subjects: Activity levels. Psychomotricity; Adult; Arousal - physiology; Biological and medical sciences; Brain; Brain - diagnostic imaging; Brain - metabolism; Brain - physiopathology; Brain Mapping; Disorders of higher nervous function. Focal brain diseases. Central vestibular syndrome and deafness. Brain stem syndromes; Electroencephalography; Fatigue; Female; Fluorodeoxyglucose F18; Fundamental and applied biological sciences. Psychology; Glucose; Glucose - metabolism; Humans; Hyperarousal; Insomnia; Male; Medical sciences; Medical treatment; Metabolism; Nervous system (semeiology, syndromes); Neural Pathways - physiopathology; Neurobiological aspects; Neurology; Positron emission tomography; Prefrontal Cortex - diagnostic imaging; Prefrontal Cortex - metabolism; Prefrontal Cortex - physiopathology; Psychology. Psychoanalysis. Psychiatry; Psychology. Psychophysiology; Sleep - physiology; Sleep Arousal Disorders - diagnosis; Sleep Arousal Disorders - diagnostic imaging; Sleep Arousal Disorders - metabolism; Sleep deprivation; Sleep Initiation and Maintenance Disorders - diagnostic imaging; Sleep Initiation and Maintenance Disorders - metabolism; Sleep Initiation and Maintenance Disorders - physiopathology; Vigilance. Attention. Sleep; Wakefulness - physiology; Radionuclide study; Human; Vigilance; Healthy subject; Central nervous system; Sleep disorder; Prefrontal cortex; Glucose; Metabolism; Encephalon; Sleep; Insomnia; Arousal; Comparative study; Emission tomography
• ISSN: 0002-953X; 1535-7228
• DOI: 10.1176/appi.ajp.161.11.2126

OBJECTIVE: The authors investigated the neurobiological basis of poor sleep and daytime fatigue in insomnia. METHOD: [18F]Fluorodeoxyglucose positron emission tomography was used to assess regional cerebral glucose metabolism of seven patients with insomnia and 20 healthy subjects. RESULTS: Compared with healthy subjects, patients with insomnia showed greater global cerebral glucose metabolism during sleep and while awake, a smaller decline in relative metabolism from waking to sleep states in wake-promoting regions, and reduced relative metabolism in the prefrontal cortex while awake. CONCLUSIONS: Subjectively disturbed sleep in patients with insomnia is associated with greater brain metabolism. The inability to fall asleep may be related to a failure of arousal mechanisms to decline in activity from waking to sleep states. Further, daytime fatigue may reflect decreased activity in the prefrontal cortex resulting from inefficient sleep.