Impact of Reward/punishment Conditions on Behavioral Inhibition and Automatic Physiological Responses in the Stages

Abstract

Though the revised reinforcement sensitivity theory(RST) provides a biological interpretation for the relationship between emotions and behavioral inhibition aroused by reward/punishment, it is still somewhat limited when attempting to explain specific phenomena. This may be attributed to factors such as the type, degree, and duration of reward/punishment stimuli, which have differed across studies. For instance, in many studies reward/punishment is a within-subjects factor, however, in clinical situations a cumulative and constant reward/punishment model is more commonly encountered, such as persistent praise or criticism of a certain individual. Furthermore, the emotion triggered by cumulative reward/punishment could manifest at any stage of the task completing process. Accordingly, this research investigated the impact of cumulative reward/punishment conditions on inhibition and automatic physiological responses during different time stages. Forty-five college students were allocated to a reward group, punishment group, or control group at random. The experiment used the Super Lab system to present stimuli and record the response time and rate of error inhibition shown by the subjects during the stop-signal task. Automatic physiological responses were collected continuously throughout the whole procedure(preparatory stage, working stage, feedback stage and reward/punishment stage) by a 16-channel physiological recording system. The results showed that:(1) in the absence of the stop-signal task, the response time of the reward group and punishment group was significantly longer than that of control group, and during the stop-signal task, the error inhibition rate of the reward group and punishment group was significantly lower than that of control group. However, there were no difference between the reward group and punishment group;(2) Heart rates within the reward group were much higher than those in the punishment group and control group, and finger temperatures were much higher than those in the control group; however, skin conductance responses in the reward group weremuch lower than those in the punishment and control groups;(3) Compared with other stages, the variation of these physical signals was much lower at the feedback stage;(4) The three groups differed in heart rate, finger temperature, and finger pulse rate at all stages, but skin conductance responses did not show significant differences across the groups. The results reveal that behavioral arousal is not synchronized with physiological arousal during reward and punishment conditions. Both the reward and punishment conditions showed inhibition to the behavioral measures, but they showed significant differences in physical arousal.