Incidental learning,attention, and curiosity in squirrel monkeys calorie deprived as infants

The long-term effects of infantile malnutrition on information processing were studied in squirrel monkeys. From 2 through 8 weeks of age, four low-calorie infants were fed reduced amounts of a high protein diet, limiting their mean body weight gain to 23% of that of four well-fed controls, with all of this gain occurring during the first 2 weeks on the low-calorie diet. Thereafter, both groups received the standard diet ad libitum. At 68 weeks of age, incidental learning was tested by introducing shape cues that were redundant to the solution of a previously learned, two-choice, color discrimination. Removal of the color cues showed that the low-calorie monkeys had learned significantly less about the shape cues than had the controls. The basis for this incidental learning failure was then examined with an embedded-figures dicrimination, to measure attentional ability, and a novel stimulus substitution task, to measure curiosity. The groups did not differ in detecting embedded figures, but the low-calorie monkeys were significantly less likely than controls to select or handle novel stimuli that had been substituted for previously learned discriminative cues. It was concluded that undernutrition in infancy may induce a long-term strategy of only learning information which leads to an immediate reward, while suppressing the acquisition of information due to intrinsic curiosity.     

The morphological asymmetry of the hemispheres and cerebral dominance for speech: A possible relationship

The asymmetry of the posterior Sylvian branches of the middle cerebral artery was examined on the carotid angiograms of 59 patients in whom the lateralization of speech representation was known from sodium amobarbital (Amytal) studies. The usual asymmetry of these vessels was found to be present in the group of patients with left-hemisphere speech representation but significantly reduced in patients with atypical cerebral dominance for speech. A model of the inheritance of handedness and cerebral dominance is extended to take account of these results.     

Regional cerebral blood flow response to recognition memory versus semantic classification tasks

Two randomly assigned groups, N = 7 each, of neurologically normal patients were composed. One group, RM, had regional cerebral blood flow measurements during a recognition memory probe test; the other group, SC, had rCBF measurements during a semantic classification task, using the same stimulus and response features as the RM task. Thus, the groups differed only in the cognitive instruction they were executing. The RM group showed a significantly lower change from resting baseline to activation, in mean left hemisphere initial slope index, than did the SC group. The RM group, but not the SC group, showed a significant inverse correlation between occipital flow and accuracy of memory performance as indicated by d′. Correlations between age and hemispheric initial slope index, and between homologous left and right hemisphere sites, were also described. The results are considered to support an anatomical basis for the distinction between episodic and semantic memory and to suggest that occipital flow may diminish with accurate memory performance because of an upstream demand of blood in the medial temporal lobes.     

Pressures and pretense: Living with gender stereotypes

This study examines how people live with two gender stereotypes: (1) masculine/active and feminine/passive roles; and (2) masculine/emotional inexpressiveness and feminine/emotional expressiveness. Given the contrast between traditional gender stereotypes and the emergent feminist perspective, we expected that both men and women would experience pressures both to conform to and to deviate from the traditional stereotypes, although the pressures would be greater for women. A study of active/passive roles and specific emotions, with a sample of 141 men and women, revealed that both sexes felt such contradictory pressures, and that they actually were greater for women. Moreover, pressures were magnified in cross-sex interaction. Pretense was one way people consciously monitor feelings and manage interactions. A number of paradoxes emerged. The most dramatic is that both men and women experienced each other as demanding stereotypical behavior, yet both claimed self-motivation for change.The author thanks Lucile Duberman for her incisive suggestions, Nancy Leff for her valuable editorial assistance, and Anne Marie Fodera and Laura Mestress for their competent work as research assistants.     

Exposure to pornography,permissive and nonpermissive cues,and male aggression toward females

The present study examined the role of permissive and nonpermissive cues in mediating the relationship between exposure to erotica and aggression. Male subjects viewed either neutral slides with a silent female or erotic slides with a female who made permissive, nonpermissive, or no comments about the slides. The males rated the slides and subsequently rated the female confederate. Male subjects were then given an opportunity to administer their choice of several intensities of shock to the female in a competitive reaction-time task. Subjects in the permissive cues condition rated the erotic slides as more arousing, saw the female as more reasonable and accepting, and selected more intense shocks for the female than did subjects in the other conditions. One explanation of these results is that permissive cues in the presence of erotica led the male to believe that other normally inappropriate behaviors would be tolerated.