Effects of the Range of Stimulus-Variation Upon Habituation of the Orienting Response

The effects of the range of stimulus-variation upon the habitation and return of the skin resistance response (SRR) component of the orienting response (OR) were investigated in three experiments using human subjects. In Experiment I the habituation and return of the OR were studied in two groups with a wide (Group-W) und a narrow (Group-N) range of stimulus-variation. Habituation in the two groups did not differ, but a differential level of return of the OR to a novel stimulus was observed. In Experiment II the difference in the range was made large and a group presented with a constant stimulus (Group-C) was added. Again Group-W and -N habituated in the same way as Group-C. In Experiment III the upper end stimulus of each group was set at the same intensity. The differential return of the OR disappeared, and as before a differential habituation could not he detected between Groups-W and -N. These findings were discussed in reference to Sokolov's neuronal model of the OR.