Psychosomatic Medicine 22:204-210 (1960)
© 1960 American Psychosomatic Society

A Comparative Analysis of Autonomic Responses in Startle

¹ Department of Psychiatry, Massachusetts General Hospital, Boston, Mass.

An analysis of the autonomic responses in the startle pattern was made by comparison to patterns reported in other studies on cold pressor stimulation, exercise, and infused norepinephrine and epinephrine.

Forty-two male undergraduates served as subjects in the present study. The following variables were recorded: systolic and diastolic blood pressures; finger, face and axillary temperatures; palmar and volar forearm skin conductances; heart and respiration rates; finger pulse volume; and stomach motility.

Startle was found different from cold pressor, exercise, and norepinephrine, but similar to epinephrine in direction of responses. It was concluded that Canon's

concept of "emergency" reactions involving undifferentiated massive discharge of the sympathetic nervous system should be regarded only as a first approximation. The startle pattern suggests a somewhat general activation of the sympathetic nervous system, but with possible parasympatheticlike activity reflected by stomach contraction period.