A method for studying visually guided perception and learning in newborn macaques

A maintenance technique was developed in which neonatal monkeys obtain all liquid food by placing their heads in a face mask mounted on their cage wall. Complete self-feeding required only 3-6 days for animals started at birth. Once under a self-feeding Schedule, operant responses were shaped to study visual perception, visually guided motor performance, and discrimination learning at ages much younger than those allowed by most alternative methods. Dark rearing, with the only source of visual input being through the face mask eyeholes, allowed the E to control completely the neonate’s visual experiences and its opportunities for visual-motor responding. The method has proven useful in rhesus monkey newborns for studying adaptation to prismatic displacement at 30 days of age, and to performance on CRF, FI, and FR reinforcement schedules.     

THE DEVELOPMENT OF CHILDREN'S PREFERENCE FOR THEIR OWN COUNTRY

Des groupes d'enfants, de 6 à 12 ans, sont testés dans six villes européennes (Oxford, Glasgow, Leyde, Louvain, Naples et Vienne) pour voir s'ils montrent une préférence pour leur propre nationalité. L'étude utilise une méthode nouvelle et simple qui garantit sans ambiguïté la comparabilité des données pour tous les âges et pour tous les pays. Les résultats montrent que (1) à l'exception du groupe de Glasgow, tous les enfants manifestent une préférence marquée pour leur nationalité; (2) à l'exception du groupe de Louvain, cette préférence est plus forte avec l'âge. Lorsqu'on compare les données obtenues à Naples avec celles des autres villes, on constate qu'un stéréotype physique national se développe chez les enfants à mesure qu'ils grandissent. Les implications théoriques des résultats et des exceptions que représentent les groupes de Glasgow et de Louvain sont commentées.     

Food-deprivation-induced behavioral arousal: mediation by hypothalamus and amygdala.

Electrolytic lesions of the basomedial hypothalamus eliminated food-deprivation-induced stabilimeter activity in rats that were prevented from becoming obese. Knife cuts lateral to the basomedial area (separating the medial and lateral hypothalamus) potentiated this activity, as did transections posterior to the basomedial region. Anterior transections (between anterior and medial hypothalamus), however, eliminated the effect. Lesions of the stria terminalis and amygdala likewise abolished deprivation-induced locomotor activity, but elevated ab-lib activity to a level comparable with that after deprivation in intact animals. Animals with combined basomedial-stria terminalis lesions behaved like animals with basomedial lesions. These results suggest that food-deprivation-induced locomotor activity in stabilimeter cages is due to a disinhibition of the basomedial hypothalamus by the amygdala via the stria terminalis.     

Effect of communication discrepancy and ambiguity on placement and opinion shift

Analyzed social judgment theory of attitude change and studied placement of a communication and opinion shift in an experiment on visual perception. In a 3 × 3 design plus a control group, 110 undergraduate college students (50 men and 60 women) received a communication after estimating the number of dots on 14 slides. The communication varied at three levels of ambiguity and three levels of discrepancy. Ss gave estimates of the communication from memory (measuring assimilation) and gave a second set of their own estimates (measuring opinion shift). Assimilation varies directly with ambiguity (p < .00l) but is unrelated to discrepancy. Opinion shift varies significantly as a function of discrepancy (p < .00l) but is unrelated to ambiguity. Authors hypothesize assimilation and opinion change may be negatively correlated at small discrepancies but directly correlated at large discrepancies.     

Interpersonal mood induction: Situational and individual determinants

Several situational and individual aspects of interpersonal mood induction were investigated in an attempt to elucidate the mechanisms by which depressed mood is transmitted from one individual to another. Eighty-four psychology students interacted with confederates previously trained to enact one of three mood states — depressed, neutral, or elated. Participants were randomly assigned to same-sex confederates in one of two roles — helper or stranger, resulting in a 3×2×2 design. Mood and self-esteem were independent variables assessed prior to the interaction. Mood, perceptions, and reactions to the confederate were dependent variables assessed following the interaction. Results indicated induction of depression and anxiety in participants exposed to depressed confederates, and induction of hostility following interaction with elated confederates. Induction of depression and hostility were significantly attenuated in participants in the helper role as opposed to person perception role, while the concept of individual vulnerability to mood induction was not supported in this study. Rejection of depressed persons was only modestly associated with negative mood induction. Thus, role components of the situation affected mood induction more than did individual participant differences. The results and their implications for therapists and family members of depressed individuals are discussed within the framework of Lazarus's cognitive model of emotional arousal.The authors gratefully acknowledge the contributions and talents of Bill Dorfman, Mike Harrington, Ginger Johnson, Anita Navarra, and Debbie Illman.     

Nutritional misinformation of children: A developmental and experimental analysis of the effects of televised food commercials

This study assessed the accuracy of judgments of 100 school age children as to the presence of real fruit content in 3 sets of cereals and beverages advertised on TV: real fruit, nonfruit, and artificially fruit flavored products. In the baseline session, accuracy was an increasing function of age, but children at each age were deceived about real fruit content of artificial fruit products. In session 2, the experimental group saw TV ads for 6 products embedded in a program (naturalistic viewing). They then judged fruit content for these six advertised products, plus a matched set of six for which ads were not shown. Controls saw toy ads on TV, and then judged the same 12 products. In session 3, subjects in each group saw the same ads they had seen in Session 2, without the program and with instruction to attend very carefully to messages in the ad (intensive viewing). They then judged all 12 products again. After naturalistic viewing, few significant differential changes from baseline were found. But after intensive viewing, accuracy of judgment of advertised artificial fruit products was lower than baseline among experimental group children. By contrast, accuracy was higher than baseline both for control children's judgements of “advertised” prod-