Aversiveness without pain: Potentiation of imaginai and auditory effects of blackboard screeches

Abstract

Sixteen subjects were presented with a mixed sequence of eight tones (T) and eight screeches (S) produced by scratching a blackboard. Half of the subjects were told how the screeches were produced (Cond I), while half were told that some sounds were complex (Cond NI). In Cond I, palmar skin potentials increased to S and remained the same to T with repeated presentations. In Cond NI, the difference between S and T remained constant over repeated presentations. Only four subjects reported having gooseflesh or unpleasant sensations. The combined effect of the screech and information regarding the way screech was produced appeared to be one of sensitization over repeated presentations. This suggested that anecdotal accounts of the effect of imaginai processes upon the reaction to this sort of sound were correct. © 1975, The Psychonomic Society, Inc.. All rights reserved.