The nature of adaptation in distance perception based on oculomotor cues

In previous work by the senior authors, brief adaptation to glasses that changed the accommodation and convergence with which objects were seen resulted in large alterations in size perception. Here, two further effects of such adaptation are reported: alterations in stereoscopic depth perception and a change when distance is represented by a response of S’s arm. We believe that the three effects are manifestations of one primary effect, an alteration of the relation between accommodation and convergence on the one hand and the distance they represent in the nervous system (registered distance) on the other. This view was supported by the results of two experiments, each of which demonstrated that the alterations in stereoscopic depth perception could be obtained after adaptation periods which had provided no opportunity to use stereoscopic vision, and that the adaptation effect was larger for depth perception than for size perception when it was obtained under the same conditions; the latter finding was expected if both effects resulted from the same change in registered distance. In three of the five experiments here reported, the variety of cues that could represent veridical distance during the adaptation period was limited. In one condition of adaptation, only the pattern of growth of the retinal images of objects that S approached and the kinesthetic cues for S’s locomotion served as cues to veridical distance. In two other conditions S remained immobile. In one of these, only the perspective distortion in the projection of the scene that S viewed mediated veridical distance, and in the other one familiar objects of normal size were successively illuminated in an otherwise totally dark field, conditions from which opportunities to use stereoscopic vision were again absent. After exposure to each of these adaptation conditions, adaptive changes in perceived size and larger ones in perceived stereoscopic depth were obtained. Because we found that familiar size may serve as the sole indicator of veridical distance in an adaptation process, we concluded that it can function as a perceptual as distinguished from an inferential cue to distance.     

Serious and playful aggression in Brazilian girls and boys

We report on an observational study on sex differences in serious and playful aggression in early childhood. The sample included 14 girls and 14 boys, aged 2 to 4. The study was carried out in Porto Alegre, Brazil. Half of the subjects attended a nursery school for children from a favela (slum district); the others attended a nursery school that was run by a local university and represented the life conditions of the middle class of the Brazilian society. Each of the children was observed at school for 3 hours (divided into 12–15 minutes episodes) through a focal sampling technique. Significant sex differences are found for the frequency of playful aggression for both the actor's and the victim's part of the aggressive act, but for the actor's role the effect holds only for the middle class setting. There are also tremendous differences between the frequencies of serious aggression in girls and some of the boys, although the effect is not statistically significant. When several types of aggression are compared, it becomes evident that sex differences are restricted to bullying (dominant aggression). The rates of instrumental and reactive aggression are similar in both sexes. Girls and boys from the favela setting do not differ in the relative importance of the different types of serious aggression, but in middle class children the proportion of acts of bullying is much higher in boys than in girls.Revised and elaborated version of the contribution to the Paper Session onFemale Aggression at the90th Annual Meeting of the American Anthropological Association in Chicago, 1991. We thank Claúdio Simon Hutz and Tânia Sperb who helped us to carry out the observations and Simone Schenk and Iris Seltenreich for help in data analysis. We are also grateful to the children and the staff of two nursery schools in Porto Alegre, Brazil, who participated in the study.     

A cusp catastrophe: Hysteresis, bimodality, and inaccessibility in rabbit eyelid conditioning

Three properties of the cusp catastrophe: bimodality, inaccessibility, and hysteresis were evaluated in rabbit eyelid conditioning. Bimodality was evidenced by the fact that responding tended to occur at either very low or very high levels, and inaccessibility by the fact that intermediate levels of responding were rarely encountered. Hysteresis was demonstrated when: (a) levels of responding attained under a continuous schedule of reinforcement were largely maintained by a schedule which was too lean to promote conditioning by itself; and (b) levels of responding attained with a high intensity unconditional stimulus were largely maintained by a lower intensity unconditional stimulus which was too weak to promote conditioning in its own right. These results are consistent with the model of conditioning suggested by P. W. Frey and R. J. Sears (Psychological Review, 1978, 85, 321–340) which postulates response-mapping rules based on the cusp catastrophe.     

Who shapes the self of independents and interdependents? Explicit and implicit measures of the self's relatedness to family,friends and partner

We suggest that social relationships shape the self in different ways, depending on whether persons define themselves as independent or interdependent. While the self of independents is most strongly associated with mental representations of others to whom they are related because of their own deliberate action (e.g. friends), the self of interdependents is most strongly connected with representations of others with whom they share allocated group memberships (e.g. family members). We took both explicit (Study 1) and implicit measures (Studies 2, 3 and 4) on how strongly independent and interdependent selves are associated with self‐chosen versus allocated close others. In Studies 3 and 4, we additionally primed the independent or interdependent self. Both explicit and implicit measures indicated that mental representations of family members were more strongly associated with the interdependent self than with the independent self, while romantic partners and friends were connected with both the independent and interdependent self. Copyright © 2006 John Wiley & Sons, Ltd.     

Postdecisional preference for decision-relevant information as a function of the competence of its source and the degree of familiarity with this information

Three experiments are reported concerning the determinants of postdecisional preferences for decision-relevant information. Two factors were considered: the competence of the source of the information and the degree of prior familiarity with the contents of the information. The first two experiments showed that the competence of the source of decision-supporting information affected the desirability of reading both types of information, whereas the competence of the source of decision-opposing information had very little effect on the desirability of reading either type. In the third experiment, the effects of giving subjects access to prior information supporting or opposing their view on their preferences for further information were investigated under conditions in which the number of choices of this later information were either limited or unlimited. The effects of prior information on choices of decision-supporting information were identical regardless of whether the total amount of information available was limited or unlimited: Less decision-supporting information was chosen when subjects had previously been exposed to decision-supporting information than when they had not, and this difference was greater when they had not previously been exposed to decision-opposing information. However, the choices of decision-opposing information under unlimited choice conditions increased with the amount of decision-supporting information previously read, but decreased with the amount of decision-opposing information previously read. The processes that underlie the choices of information under conditions in which several types are available are discussed.     

“Man's best friend:” How the presence of a dog reduces mental distress after social exclusion

A substantial amount of research shows that social exclusion is a threat to mental health. In the research reported here, we tested the hypothesis that the presence of a companion animal can serve as a buffer against these adverse effects. In a controlled laboratory experiment, we found that only socially excluded participants who did not work in the presence of a dog reported lower mental well-being compared with socially excluded participants who performed in the presence of a dog and participants who were not socially excluded. The theoretical and practical implications of these findings are discussed.     

Two-year follow-up of an interdisciplinary cognitive-behavioral intervention program for obese adults

Intervention programs for treating adiposity which focus on dietary change and physical exercise often do not lead to the desired long-term reduction in weight. This article reports on the effectiveness of M.O.B.I.L.I.S., a standardized theory-driven intervention program. Participants are taught cognitive-behavioral strategies of goal setting, action planning, barrier management, and self-monitoring. Persons with obesity (N=316) responded to a public advertisement to participate in the intervention program (IG) or comparison group (CG; quasi-experimental design). Assessments were conducted at four time points, with the last assessment being conducted two years after baseline. At the 24-month follow-up, the IG showed weight loss of 5.57%, whereas the CG lost 1.12% of their weight (t1-t4, p < .01). The results yielded significant interaction terms (group x time), indicating that the intervention had a substantial effect on food choice and level of physical exercise (p < .01). The IG showed significantly enhanced self-efficacy, stronger goal intentions, and more detailed implementation intentions than the CG at follow-ups. The intervention program has the potential to evoke enduring changes in the cognitions we hypothesized to be responsible for inducing obese adults to begin and continue regular exercise and healthy eating behavior, resulting in substantial weight loss.     

Anger and sadness in response to an emotionally neutral film: evidence for age-specific associations with well-being

When the association between emotion and well-being is being considered, positive emotions usually come to mind. However, negative emotions serve important adaptive functions and particular negative emotions may be especially adaptive at different stages of adult development. We examined the associations between self-reported negative emotions in response to an emotionally neutral, thematically ambiguous film and subjective well-being among 76 young (age 20-29), 73 middle-aged (age 40-49), and 73 older (age 60-69) adults. Results indicated that higher self-reported anger in response to the film was associated with higher well-being for middle-aged adults, but not for young and older adults. Higher self-reported sadness in response to the film was associated with higher well-being for older adults, but not for young and middle-aged adults. These findings were stronger for cognitive well-being (i.e., satisfaction with life) than for affective well-being (i.e., ratio of dispositional positive to negative affect) and were specific to these emotions (not found for self-reported disgust or fear) and to the emotionally neutral film (not found for sad or disgusting films). Results are discussed in terms of the functions that anger and sadness are thought to serve and the control opportunities afforded in midlife and late life that render these functions differentially adaptive.     

Sex differences,sex-role orientation,and reward allocations

In study 1, 52 male and 52 female undergraduates allocated rewards to pairs of children for their performances in team and competitive situations. Males allocated rewards more equitably, especially when allocating to boys in competition, while females allocated rewards more equally. Boys, but not girls, who did more work received more rewards than their partner; and children with greater work inputs under competitive conditions received more rewards than children in team conditions. In study 2, the sex-role orientation of 60 college students was found to be related to their reward allocations. Males and females with a masculine sex-role orientation allocated rewards equitably, while individuals with a feminine sex-role orientation allocated rewards equally. Results indicated that sex and situational differences in reward allocations are affected by sex-role orientation and differential socialization practices by adults.Portions of study 1 were presented at the Midwestern Psychological Association Meeting, Chicago, May 1978.