This study examines the sleep architecture (polysomnography) of patients with sleep panic attacks and related parasomnias in comparison with that of normal controls and panic disorder patients without sleep panic attacks. The polysomnographic study of patients with other anxiety disorders such as social phobia, nightmares, post-traumatic stress disorder (PTSD) and anxiety dream disorder will also be conducted for comparison purposes. Continued analysis of such factors as movement time, REM latency, wakefulness after sleep onset, and sleep efficiency among the groups is an ongoing focus of research. The study of sleep panic attacks is a major focus of research for the Section. Evidence from the sleep laboratory continues to indicate that sleep panic attacks emerge from non-REM sleep -- typically either stage 2 or 3. On the nights when patients have had panic attacks, a prolonged REM latency has been noted, in contrast to the shortened REM latency of depression. New methods of data analysis of sleep records are being developed such as recording number of K-complexes, spindles, and performing spectral analysis of data for between group comparisons. The Section is develop- ing a methodology for quantifying vagal tone during sleep. Future studies will investigate the behavioral, biochemical, and neuroendocrine effects of chemical panicogenic agents administered during sleep in panic disorder patients and normal control subjects.
