Effects of sensory deprivation on introverts and extraverts: a failure to find reported differences

This study was stimulated by an earlier study by another investigator in which it was found that extraverts and introverts differed in their tendencies to quit the SD experiment prematurely, in amounts of movement during SD, and in their thought processes during SD. The present study compared 10 extraverts and 10 introverts in their reactions to SD. Ss were placed in a sound-deadened room with halved ping-pong balls covering their eyes and cardboard cuffs enclosing their lower arms and hands. The room was well-lighted and white noise was conveyed to Ss via headphones; however, Ss' eye coverings diffused the light and the loudness of the white noise blocked out ambient sounds so that Ss received only unpatterned visual and auditory stimulation. Ss were in SD for 3 h unless they requested early release. The two groups of Ss were compared on the following data: (a) Numbers of each group who quit the experiment prematurely; (b) Verbal reports given during SD; (c) Observations and recordings of visible movements during SD; (d) Self-ratings of well-being on a semantic differential type rating scale before and after SD; (e) Scores on the Minnesota Multiphasic Personality Inventory. The results disclosed no statistically significant differences between extraverts and introverts on any of the measures employed. These results were at variance with results obtained in the earlier study despite much similarity in S selection and method employed in both studies. The divergency of results suggests that whatever relation may exist between the extraversion-introversion dimension and reactions to SD may take more than 3 h to manifest itself or may interact with other, as yet unknown, variables to such an extent as to make the relation unstable in small samples.