Forearm Blood Flow in Normal Subjects and Patients with Phobic Anxiety States

Abstract

Estimations of forearm blood flow using a mercury-in-rubber strain gauge plethysmograph were carried out on two groups of female subjects, ten normals and ten patients with severe phobic anxiety states. Mental arithmetic stress was associated with a significant elevation of forearm blood flow in both groups. There were no statistically significant differences between the normal and neurotic groups in respect of resting flow, peak flow during stress, and after stress scores. Some subjects were exposed to additional stress situations. Our results suggest that an elevation of forearm blood flow is associated with the subjective experience of acute anxiety, but that depression and tearfulness does not elicit this response. Forearm blood flow was not raised during a state of transient hysterical dissociation. The significance of the results in relation to the occurrence of fainting in states of acute anxiety is discussed. Further experiments are indicated to determine the latency and duration of the forearm flow response to stress in different situations and subjects, the frequency with which the response can be elicited and to what extent adaptation takes place. The method is a convenient technique for estimating muscle blood flow which is acceptable to neurotic patients.