Social position and competition in laboratory rats.

Two experiments with rats as subjects are described, which control for social position, i.e., relative dominance/submission, in an appetitive social learning-performance setting. The results indicate that animals that perform quite effectively when alone exhibit significantly reduced levels of responding when placed into a social environment. The severity of the response decrement is, at least in part, a function of the relative social position of the subjects involved. A dominant male made few responses when paired with another dominant male. Yet, a dominant subject made even fewer responses when paired with a submissive subject, which bar pressed at approximately half the individual level. These findings are interpreted as suggesting that social position, with its accompanying characteristic form of aggression, is an important determinant of performance in a social learning environment.     

Role selection in the service of self-presentation

Two experiments were conducted to examine the general hypothesis that a person’s behavior in a social situation is a function of the kind of impression he wants to make on the other person, and that the kind of impression that he wants to make is influenced by the characteristics of the other person. Two experiments were conducted in which male subjects anticipated interaction with either an attractive female (attractive condition), an unattractive female (unattractive condition), or a female whose attractiveness was unknown (control). Each subject first chose either a high, medium, or low status role to enact during the interaction with the female. He then indicated the role which most closely corresponded to his true role. In Experiment I, role choices were significantly biased in the direction of higher status roles in the attractive condition but not in the unattractive or control conditions. These findings were partially replicated in Experiment II, but difference was shown to be a consequence of the fact that the experimenter was an attractive female. The subjects biased their reports of true role status in the direction of higher status, thus leaving little room for change in the selection of role to be enacted during the social interaction. These findings are consistent with the general hypothesis and with exchange theory predictions.     

Degree of training and the novelty transfer effect

Four groups of 40 Ss were given transfer tests following 2.4, 6, or 8 14-trial blocks of paired-associate training with unequal stimulus frequencies and then retested after a further training period in which the same compound stimuli were presented at equal frequencies. The novelty effect, in which Ss respond to new combinations of training components by giving the response associated with the least frequent component, was obtained in every transfer test. It was concluded that the novelty effect is a mode of responding that is produced by differential frequencies during early learning and which, once adopted, is retained by Ss regardless of whether the frequency differential is maintained.     

Cortical potentials evoked by confirming and disconfirming feedback following an auditory discrimination

Vertex potentials elicited by visual feedback (signals following an auditory intensity discrimination have been studied with eight Ss. Feedback signals which confirmed the prior sensory decision elicited small P3s, while disconfirming, feedback elicited P3s that were larger. On the average, the latency of P3 was also found to increase with increasing disparity between the judgment and. the feedback information. These effects were part bf an overall dichotomy in waveshape following confirming vs disconforming feedback. These findings are incorporated in a general model of the role of P3 in perceptual decision making.     

Expectancy confirmed again: A computer investigation of expectancy theory

A computerized attempt to replicate Aronson and Carlsmith's test of expectancy theory was conducted. Generally, subjects performed consistent with their expectancy, although the effect of expectancy was strongly attentuated by an overall achievement orientation. The results contradict the hypotheses that experimenter bias, demand characteristics, or differential recall of performance mediate the effects of expectancy upon performance.     

Analysis of the development of children's spatial reference systems

Four, six, and ten-year-old children were required to copy an object's location and orientation within a two-dimensional spatial layout under two conditions: when both E's standard board and that of the S's were in the same orientation and when they were rotated 180 ° from each other. The failure of the 4-yr-olds to copy location and orientation under both conditions even when space was topographically coded indicates that at this age the child does not conceptualize space within two dimensions. Although the errors of the 4-yr-olds tended to be of a self-reference nature with respect to orientation and location on rotation trials the axes of the self-reference system were not coordinated. Six and 10-yr-old children performed significantly better on both conditions, with the exceptions that the 6-yr-olds continued to preserve some orientations within a self-reference system. When topographical codes were removed and S imagined rotation there were no significant age differences in total errors; however, older children organized entire subspaces within a self-reference system. The findings support Piaget and Inhelder's hypothesis that two-dimensional reference systems do not develop until the period of concrete operational thought, and they also indicate that even at age 10, the self-reference system continues to function when topographical codes are absent. Several cognitive mechanisms proposed to account for the development of spatial abilities are critically discussed.     

Fingertip force,surface geometry,and the perception of roughness by active touch

Ss made magnitude estimates of the perceived roughness of grooved metal plates under conditions of active touch with controlled finger force. The wider the grooves in the plate, the narrower the lands between the grooves, or the greater the finger force, the greater was the perceived roughness. Increase in finger force also slightly increased the slope of the magnitude estimation function, suggesting not only that the roughness of a uniform surface but also the contrasts in the roughness of differing parts of a patterned surface would be altered by changes in the manner of feeling the surface. An analogous effect has been reported in vision, in that increases in illumination increase the apparent contrast of a surface.