Synopsis
Galvanic skin response (G.S.R.) inhibition thresholds, giving an index of barbiturate tolerance, were determined for 20 depressive and 10 normal subjects. Barbiturate tolerance was found to effectively differentiate neurotic from psychotic depressives, and both these groups from normal controls. Neurotic depressives generally exhibited high G.S.R. inhibition thresholds relative to normals, while psychotic depressives exhibited low thresholds relative to normals. These results are discussed in terms of previous research on the sedation threshold.
The G.S.R. inhibition threshold was found in some groups, to be systematically influenced by manifest anxiety. However, neither depressive severity nor age influenced barbiturate tolerance. Some potential clinical and experimental uses of the G.S.R. inhibition threshold are discussed.