Forgetting and conditioned suppression: role of a temporal discrimination

Several experiments have found complete retention of conditioned suppression when overall suppression to the signal for shock was measured. The present experiment examined retention of conditioned suppression but did so with a paradigm that produced temporal discrimination of shock occurrence. Nine rats were exposed to a flashing light signal of 5-min duration that always terminated with a shock. After several months, a temporal discrimination was well established, as shown by maximum suppression toward the end of the signal period. After remaining in the home cage for 25 days, the rats were again subjected to the conditioning procedure. The overall level of suppression remained the same but the temporal discrimination was not observed.     

The acquisition of conditioned emotional response as a function of intertrial interval

The effects of intertrial interval (ITI) and foreperiod duration on the acquisition of a conditioned emotional response were investigated using a four-trial conditioning procedure. The optimum ITI was found to be 60 s with a bidirectional gradient for conditioned suppression above and below 60 s. Conditioned supression was found to be directly related to foreperiod duration.     

Mousekilling,intermale fighting,and conditioned emotional response in rats

Several possible relationships between two forms of aggression in rats were studied. First, mouse killing and spontaneous intermale fighting were found to be correlated. Rats which attacked other rats were those most likely to kill mice. To determine whether aggressive and nonaggressive rats were also differentially responsive to other situations involving emotional arousal, but not aggression, mouse-killers and nonkillers were compared in a conditioned emotional response (CER) situation. Mouse-killers showed greater suppression to the conditioned stimulus (CS) and to the situational cues of the apparatus. Therefore, a common arousal mechanism may underlie a number of diverse agonistic responses. Nevertheless, extensive mouse-killing experience did not increase the tendency of rats to fight with either adult males or juvenile males.     

The effect of person on a conditioned emotional response of schizophrenic and normal subjects

Thirteen normal and 13 schizophrenic Ss were given 100 tone-shock trials over five days under four conditions: the S alone in the experimental room, a person present in the room, the person talking to the S, and the person massaging the S’s shoulder. Results showed an inhibitory effect of the social stimulus on the HR-CR and HR-UR of normals. For schizophrenics, conversely, the effect of the social stimulus was to increase HR responses during tone-shock and social interactions. A social learning analysis suggested early emotional and autonomic conditioning to significant persons and later generalization to others as primary determinants of HR indices of social responding. It was suggested that variation of the past relationship with anE and measurement of Ss’ perceptions of the experimenter-social stimulus together with physiological responses could contribute to analysis of the component variables of affectional and attachment responses.