AUTONOMIC CHARACTERISTICS OF NONCLINICAL PANIC AND BLOOD PHOBIA

Autonomic characteristics of nonclinical panic and blood phobia were c ompared using spectral analysis of the electrocardiogram (EKG), as wel l as more conventional cardiovascular measures. The cardiovascular res ponses of 11 subjects who reported recent occurrence of frequent sever e panic attacks, and 10 subjects who reported intense somatic reaction s to the sight of blood (including episodes of syncope) were recorded during a variety of laboratory tasks (quiet rest, reaction time/shock avoidance, face immersion, and combined reaction time/face immersion). Results suggest distinct autonomic patterns in the groups. Panickers showed (a) higher heart rate and reduced heart-rate variability (b) ab errant associations among cardiovascular measures, and (c) dominant sy mpathetic control of heart rate coupled with diminished vagal tone. Bl ood phobics generally displayed an opposite pattern. The relevance of these findings to the etiology of panic and blood phobia, as well as t o biological models of anxiety disorders in general, is discussed.