Sequencing of behaviors in Aplysia fasciata: integration of feeding, reproduction, and locomotion.

To begin studying the neural basis of higher-order decision-making in Aplysia fasciata, we examined individual bouts of behavior in various conditions of access to food and/or mates. We then determined rules governing transitions between bouts. The data indicate that a single intermediate condition, moving in place, may be centrally related to transitions between behaviors. In all conditions, over 85% of all transitions between behaviors were via moving in place. Moving in place tended to precede and follow other categories of activity (crawling, swimming, immobile), and feeding. Also, moving in place apparently represents a fixed proportion of all bouts of behavior. In each condition, moving in place represented approximately 40% of all bouts, while the number of bouts of other behaviors varied markedly. After a bout of moving in place there was a strong tendency for the animal to return to the behavior performed before moving in place. Additional preferred sequences of behavior were also seen. Courtship tended to precede mating, and crawling preceded swimming.     

Effects of conspecifics on feeding in Aplysia fasciata

The presence of other Aplysia in the environment increases the time spent feeding. This finding is consistent with the hypothesis that a common arousal mechanism modulates feeding and reproductive behaviors. The arousal level is presumably increased by pheromones released by additional animals.     

The effects of exposure to political and domestic violence on preschool children and their mothers

The purpose of this study was to examine the effects of exposure to political violence on preschool children and their mothers. We explored whether these dyads are different from dyads with no known history of exposure to violence and from mother–child dyads with known exposure to domestic violence. Specifically, we explored differences in mothers' psychological status (depression and anxiety), dyadic emotional availability (EA), children's social information processing, and children's social behaviour, in a sample of 216 dyads divided into three groups (exposure to political violence, no exposure to violence, and exposure to domestic violence). We found evidence to support our hypotheses that children exposed to domestic violence exhibit the highest levels of social maladjustment with smaller but still significant differences between children exposed to political violence and children in the comparison group. As expected, the lowest EA scores were found in the exposure to domestic violence group, followed by dyads in the exposure to political violence group. Dyads belonging to the comparison group (no exposure) exhibited the highest levels of EA. These findings contribute to our understanding of the meaning of exposure to political violence, as well as sharpen the difference between exposure to political and domestic violence.     

Relations Between the Development of Teaching and Theory of Mind in Early Childhood

The relations among children’s theory of mind (ToM), their understanding of the intentionality of teaching, and their own peer teaching strategies were tested. Seventy-five 3-, 4-, and 5-year-olds completed 11 ToM and understanding-of-teaching tasks. Subsequently, 30 of the children were randomly chosen to teach a peer how to play a board game, and their teaching strategies and levels of contingent teaching were recorded. There were developmental changes in the children’s understanding of teaching as an intentional activity. When teaching their peers, 3-year-olds used demonstration, whereas 4- and 5-year-olds added verbal explanations and began to adapt contingently to the learners’ changing knowledge level. Relations among ToM, understanding of teaching, and teaching level were found. The results suggest that the development of children’s teaching strategies and their contingency are closely tied to the development of ToM.     

Children's understanding of teaching: the role of knowledge and belief

The relation between preschoolers’ concept of teaching and theory of mind was explored to determine if there is a developmental change in understanding how teaching depends on knowledge and belief. The study tested whether 3- to 6-year-olds thought the awareness of a knowledge difference is necessary for teaching. The 3- and 4-year-olds understood teaching stories with clear knowledge differences and could correctly use that information to specify the teacher and learner. The 5- and 6-year-olds, who performed well on a standard false belief task, further understood that it was the teacher's belief about the knowledge difference that would actually govern teaching. The conceptual link to teaching suggests that theory of mind is critical for understanding other forms of knowledge acquisition besides perceptual access.     

Birth order effects on the separation process in young adults: an evolutionary and dynamic approach

The present study analyzes the differential contribution of a familial or social focus in imaginative ideation (the personal fable and imagined audience mental constructs) to the separation-individuation process of firstborn, middleborn, and lastborn children. A total of 160 young adults were divided into 3 groups by birth order. Participants' separation-individuation process was evaluated by the Psychological Separation Inventory, and results were cross-validated by the Pathology of Separation-Individuation Inventory. The Imaginative Ideation Inventory tested the relative dominance of the familial and social environments in participants' mental constructs. The findings showed that middleborn children had attained more advanced separation and were lower in family-focused ideation and higher in nonfamilial social ideation. However, the familial and not the social ideation explained the variance in the separation process in all the groups. The findings offer new insights into the effects of birth order on separation and individuation in adolescents and young adults.     

The effect of humor on aggression catharsis in the classroom

Two studies were designed to measure the cathartic effects of humor on aggressive responses. In the first study, two versions (easy and difficult) of Raven's intelligence test were administered to two groups of high school students. Only the easy version could be solved in the alloted time. Rosenzweig's (1951) Picture Frustration test was then administered and the students' aggressive responses were scored. Results showed that those who did not solve the problems had significantly higher scores on aggressivity than did the others. The second study, using four different groups, was planned according to a modified Solomon design. Two of the four groups of students completed the difficult part of the Raven test, and then two video-tapes were presented: a humorous one to two groups and a neutral one to the others. Finally, the Rosenzweig Picture Frustration test was administered to all four groups. An analysis of variance computed on the aggressivity scores showed one significant difference: frustrated students who viewed the humorous videotape had lower scores than those viewing the neutral one.     

Nature and nurture in own-race face processing

A standard visual preference task was used to examine 3-month-olds' looking times at own-race versus other-race faces as a function of environmental exposure to faces from the two categories. Participants were Caucasian infants living in a Caucasian environment, African infants living in an African environment, and African infants living in a predominantly Caucasian environment. The results indicate that preference for own-race faces is present as early as 3 months of age, but that this preference results from exposure to the prototypical facial environment.     

Focal lung pathology detection in radiology: Is there an effect of experience on visual search behavior?

In radiology, 60% to 80% of diagnostic errors are perceptual. The use of more efficient visual search behaviors is expected to reduce these errors. We collected eye-tracking data from participants with different levels of experience when interpreting chest X-rays during the completion of a pathology-detection task. Eye-tracking measures were assessed in the context of three existing visual search theories from the literature to understand the association between visual search behavior and underlying processes: the long-term working memory theory, the information-reduction hypothesis, and the holistic model of image perception. The most experienced participants (radiology residents) showed the highest level of performance, albeit their visual search behaviors did not differ from the intermediate group. This suggests that radiology residents better processed the represented information on the X-ray, using a visual search strategy similar to the intermediate group. Since similar visual search resulted in more information extraction in the radiology residents compared with the intermediates, we suggest that this result might support the long-term working memory theory. Furthermore, compared with novices, intermediates and radiology residents fixated longer on areas that were more important to avoid missing any pathology, which possibly confirms the information-reduction hypothesis. Finally, the larger distances between fixations observed in more experienced participants could support the holistic model of image perception. In addition, measures of generic skills were related to a lower time cost for switching between global and local information processing. Our findings suggest that the three theories may be complementary in chest X-ray interpretation. Therefore, a unified theory explaining perceptual-cognitive superiority in radiology is considered.