Discriminability and criterion differences between extraverts and introverts during vigilance

In a signal detection task introverts were better able than extraverts to distinguish between the signal and noise distribution (p < .001) and also set a higher criterion point for their responses (p < .01). The results show that superior vigilance in introverts reported by other investigators is due to two processes.     

Sex differences in rats' response to novelty measured by activity and preference

Rats were familiarized to one compartment of a test box and then given access to this and a novel compartment. Females spent more time in the novel compartment than males did and this difference was found to be independent of a possible difference in familiarity with the familiar compartment arising from the females' higher frequency of ambulating and rearing with sniffing during familiarization. This is evidence of a sex difference in response to novelty independent of activity differences. Females also had shorter approach latencies to the novel compartment. These sex differences could reflect differences in either fearfulness or curiosity.     

REDUCING AGGRESSIVE AND SELF-INJURIOUS BEHAVIOR OF INSTITUTIONALIZED RETARDED CHILDREN THROUGH REINFORCEMENT OF OTHER BEHAVIORS1

Aggressive and self-injurious behaviors of four retarded children were reduced by combining various techniques with the differential reinforcement of other behaviors (DRO). In one study, aggressive responses of a severely retarded child were reduced when DRO was combined with a 30-sec timeout. In a second study, various aggressive classroom behaviors were reduced when the child was told “no” for an inappropriate response but earned puzzle pieces for periods of time when inappropriate responses did not occur. Exchangeable tokens were given to a third subject for every 15 min in which aggressive responding did not occur, while each inappropriate response resulted in the loss of all tokens accrued. Responding was decreased to a level far below baseline. For a fourth child, self-injurious responses were followed by “no”, and intervals of time in which no self-injurious responding occurred earned candy. The rate of this behavior reduced significantly. In each case, the DRO procedure combined with the other techniques proved to be manageable for the teacher and successful in reducing the inappropriate behavior.     

Receiving Help,Reciprocation, and Interpersonal Attraction1

In a 3 × 3 factorial experiment with 3 additional cells, 329 male or female subjects working with two same-sex confederates (A and B), received either voluntary, involuntary, or no help from A after which attraction to A and B were measured for one-fourth of the subjects. The remaining subjects were assigned to a second set of tasks and were induced to help A, help B, or were not given an opportunity to help, after which they completed attraction and mood measures. Subjects were more likely to volunteer help after the second task when they had received prior help. Receipt of help led to more liking for the helper and the helper was liked more when subjects were able to reciprocate. Attraction and mood results are discussed in relation to attractiveness mediation, modeling, and indebtedness explanations for reciprocity.     

Development of verbal control over bizarre gestures of retardates through imitative and nonimitative reinforcement procedures

Two retardates, manifesting hand gestures and minimal instructional control, were trained by imitative reinforcement procedures to imitate a response that was in contrast to gesturing. Next, with the contrast response continuing to be imitatively reinforced, gesturing was reduced by nonimitative reinforcement procedures; while providing facial and gesture cues, the adult said, "Do not do this". Imitative and nonimitative procedures were found to have the same effects on the contrast response as on the gesturing response, such that imitative procedures increased both responses, whereas nonimitative procedures decreased both. Nonperformance of gesturing was further maintained when (1) explicit verbal directions for nongesturing were superimposed upon the demonstrational-facial-verbal cues as these collective stimuli were faded out and (2) food reinforcers for nongesturing were gradually removed while social consequences continued to be administered.