Relationship of Induced Muscle Tension to Phenomenon of Brightness Constancy

Abstract

11 male and 11 female college students at California State College, Los Angeles were tested for brightness constancy perception while experiencing induced muscular tension (IMT). One-half S's maximum grip on a standard hand dynomometer was used for induced muscular tension. IMT was expected to increase activation and attention, and facilitate veridicality of perception in the brightness constancy situation. A repeated measures design was used; each S ran through the constancy test twice, once with IMT, once without. A difference score was calculated for each S by substracting the scores obtained with IMT from those obtained without. The t test ( p < .05; t = 2.23) was in the opposite direction from the predicted. IMT heightened activation, but the outcome was facilitation of brightness constancy, not veridicality.