Label training and auditory generalization

To investigate the Miller-Dollard hypothesis (Social learning and imitation, New Haven: Yale University Press, 1941) that verbal labels increase distinctiveness of cues, generalization gradients to pure tones were obtained before and after label training. One group was trained to label all seven tones in an array and another only the middle tone. Three additional groups controlled for nonverbal factors. Before training, gradients were characterized by progressive loss of stimulus control with exposure to the generalization test stimuli. The main effect of possession of labels was to retard this loss, but only in tests where S+ was a labeled stimulus. While the specificity of label effects was in line with the Miller-Dollard hypothesis, the finding that labels did not confer a clear advantage at the start of testing was not. It was suggested that the unlabeled stimuli may have been sufficiently distinct to mask label effects and that interference generated by the test stimuli reduced distinctiveness to levels needed for such effects to emerge.     

Prediction outcome and choice reaction time: Inhibition versus facilitation effects

In two-choice RT tasks Ss verbally predicted all stimulus presentations, two-thirds of the presentations, or none of the presentations. Effects of stimulus probability were similar for each type of prediction trial: Correct Prediction Outcome (PO), Incorrect PO, and No-Prediction (NP). When comparisons between Prediction and NP trials were between Ss, reactions on NP trials were significantly faster than reactions POs, but were not slower than reactions to Correct POs. However, when Prediction and NP trials occurred within Ss, reactions on NP trials were not faster than reactions to Incorrect POs, but were significantly slower than reactions to Correct POs. Speculations about Ss' implicit stimulus predictions are offered to interpret differential implications of inhibition and facilitation.     

Transfer between downshift in reward magnitude and continuous delay of reward

Two separate experiments were conducted to investigate transfer of persistence between delay and a downshift in reward magnitude. In the first experiment, experimental rats were initially downshifted in reward magnitude and later tested for persistence to continuous delay of large reward. It was found that these rats were more persistent to the effects of delay than control rats which did not receive prior experience with a downshift in reward magnitude. In the second experiment, experimental rats were first trained to receive large reward under delayed conditions and then tested for persistence to a downshift in reward magnitude. Compared to control rats which received no prior experience with delay, the experimental rats showed a significantly smaller negative contrast effect. The results were interpreted as supporting Amsel's theory of persistence as well as Capaldi's recent interpretation of contrast effects.     

Stimulus control of responding in the early trials of differential conditioning

In Experiment 1 two groups of rats were given 12 differential conditioning trials, seven to the rewarded alley (S+) and five to the nonrewarded alley (S?), prior to being extinguished in both alleys. Group S?S+ received S+ trials, following S? trials in acquisition, while Group S+S? did not receive S+ trials following S? trials in acquisition. In extinction S+ and S? trials were presented according to a quasi-random sequence for both groups. Running on the last 3 trials of acquisition was found to be faster following S+ than following S? trials. Group S?S+ showed greater resistance to extinction and less discriminative responding in extinction than Group S+S?. These results suggest that responding in differential conditioning is controlled not merely by S+ and S? but by the memories of reward (S^R) and of nonreward (S^N) as well. When the joint effects of both classes of cues were considered, e.g., S^R+S+, responding in the early trials of differential conditioning was shown to be highly orderly. Experiment 2 was highly similar to Experiment 1 except that Groups S?S+ and S+S? were equated along dimensions not equated in Experiment 1. The results obtained in Experiment 2 were highly similar to those obtained in Experiment 1.     

The center and range of the probability interval as factors affecting ambiguity preferences

Ambiguous decision situations are characterized as having probabilities that are uncertain. The uncertainty is due to the common, real-world deficiency of information about the process by which the outcomes are determined. Thirty lotteries having uncertain probabilities were constructed by varying the centers and the ranges of the intervals within which the imprecise probabilities of winning could lie. Pairs of the lotteries were presented as choice alternatives to subjects, with each pair having lotteries with the same interval center but differing interval ranges. Ambiguity avoidance, the selection of the less ambiguous option, was found to increase with the interval center C, with ambiguity indifference occurring for values of C ? 0.40. No evidence of ambiguity seeking as the prevalent behavior was obtained. Ambiguity avoidance did not significantly increase with the interval range R, but an interaction effect between C and the ranges R₁ and R₂ of the choice pair was obtained. This effect of the ranges could not be described simply by knowledge of the difference R₁ ? R₂; knowledge of both individual values was necessary. The theoretical implications of these results are discussed.     

Being attractive,advantage or disadvantage? Performance-based evaluations and recommended personnel actions as a function of appearance,sex, and job type

Prompted by a concern with the effects of appearance on how individuals and their work are regarded and how rewards are allocated in work settings, an experiment was conducted to determine whether physical attractiveness differentially affects the performance evaluations and recommended personnel actions for men and women holding managerial and nonmanagerial jobs. As predicted, attractiveness proved to be advantageous for women in nonmanagerial positions and disadvantageous for women in managerial ones. Unexpectedly, however, appearance had no effects whatsoever on reactions to men. Additional results indicated that attractiveness enhanced the perceived femininity of our female stimulus people, but did not enhance the perceived masculinity of those who were male. These data were interpreted as supportive of the idea that the differential effects of appearance in work settings are mediated by gender characterizations, and that fluctuations in the perceived person-job fit are key to understanding the seemingly inconsistent reactions to attractive and unattractive women in employment situations. The theoretical and applied implications of these findings are discussed.     

Human medial temporal-lobe stimulation disrupts both formation and retrieval of recent memories

Disrupting medial temporal-lobe (MTL) activity for less than a second, either during the initial presentation of a complex scene or when it is presented again 1 min later, severely impairs recognition at the second presentation. MTL disruption during both presentation and recognition periods produces further impairment. These results are not consistent with views limiting MTL function solely to encoding or solely to retrieval mechanisms.     

Allocentric versus idiocentric tendencies: Convergent and discriminant validation

Allocentric tendencies were studied with a multimethod questionnaire and Illinois undergraduates. Nine scales measuring different aspects of allocentrism were shown to have good reliability and to be intercorrelated, thus showing convergent validity. Factor analysis identified three aspects: subordination of personal to group goals, the ingroup as extension of the self, and ingroup identity. The scales also had satisfactory discriminant validity. Those high on idiocentric tendencies used equity and those high in allocentric tendencies used equality and need in distributing rewards. A second study found that those who are allocentric are more likely to emphasize the values of cooperation, equality, and honesty, and those who are idiocentric to emphasize the values of comfortable life, competition, pleasure, and social recognition. Those who were allocentric reported receiving more social support and a better quality of social support; those who were idiocentric were higher in achievement motivation, alienation, anomie, and reported greater loneliness.