Group measurement of palmar perspiration as an index of tension

This study was concerned with changes in palmar perspiration level due to a stress-producing situation. The relationship of this measure to manifest anxiety and the personality scales on the Minnesota Multiphasic Personality Inventory was also investigated, as well as the effect of tension on ability to recall non-stressful and stress-producing memories. It has been known for quite some time that body perspiration is controlled by the parasympathetic and sympathetic branches of the autonomic nervous system. Recent research of Kuno1 and others, indicates that sweat glands on the palmar surface of the hand are minimally sensitive to thermal changes, and extremely sensitive to stimulation by the sympathetic nervous system as influenced by psychic factors, such as tension or stress. The subjects used in this study were a class of forty-one female student nurses at the same level of training. These subjects were given an oral examination in which they were asked to define twenty terms, ten easy and ten difficult. During the examination a palmar perspiration index was obtained from each subject. At the next class period, the Minnesota Multiphasic Personality Inventory was administered, from which the Taylor Manifest Anxiety Scale could also be scored. The baseline or relief perspiration index, aong with the students' rating of "difficult" or "easy" for each term, was also taken at this time. A colorimetric technique was used in recording the perspiration indices, and average readings were then determined with a densiometer. The following results were obtained: 1. A significant difference between the tension and relief perspiration indices. The critical ration of 4.94 was reliable beyond the .01 level of confidence. Thirty-four of the forty-one subjects had a higher tension index. 2. A significant difference between the recall of "easy" and "diffcult" terms. The critical ration 6.89 was reliable beyond the .01 level of confidence. Thirty-eight of the forty-one subjects remembered more "eas" terms than "difficult ones. 3. The Taylor Scale of Manifest Anxiety correlated .39 with tension indieces and .22 with relief indices. 4. There were no reliable differences between a high "perspiration index" group and a low "perspiration index" group on the M.M.P.I. scales. From the results of this and previous studies, the perspiration index would appear to be a reliable measure of tension as produced by stressful situation. It also appears to have some relationship to manifest anxiety as measured by the Taylor Scale on the M.M.P.I. The stress situation in the present study produced significantly greater recall on "easy" terms as compared with "difficult" ones, which is further evidence for a concept of defensive forgetting.