Evidence for a gene-environment interaction in predicting behavioral inhibition in middle childhood

Gene-environment interactions are presumed to shape human behavior during early development. However, no human research has demonstrated that such interactions lead to stable individual differences in fear responses. We tested this possibility by focusing on a polymorphism in the promoter region of the gene for the serotonin transporter (5-HTT). This polymorphism has been linked to many indices of serotonin activity. Specifically, we tested the hypothesis that an interaction between children's 5-HTT status and maternal reports of social support predicts inhibited behavior with unfamiliar peers in middle childhood. Results were consistent with this hypothesis: Children with the combination of the short 5-HTT allele and low social support had increased risk for behavioral inhibition in middle childhood.     

Transcranial direct current stimulation of the right temporoparietal junction impairs third-person perspective taking

Given the current debates about the precise functional role of the right temporoparietal junction (rTPJ) in egocentric and exocentric perspective taking, in the present study we manipulated activity in the rTPJ to investigate the effects on a spatial perspective-taking task. Participants engaged in a mental body transformation task, requiring them to mentally rotate their own body to the position of an avatar, while undergoing anodal, cathodal, or sham transcranial direct current stimulation (tDCS) of the rTPJ. As a control task, participants judged the laterality of a stimulus feature with respect to a fixation cross on the screen. For the first half of the experiment (only during online tDCS), a task-selective effect of tDCS was observed, reflected in slower reaction times following anodal than following cathodal and sham tDCS for the mental body transformation task, but not for the control task. The effects of tDCS were most pronounced for stimuli implying a more difficult mental body transformation. No effects of tDCS were observed during the second half of the experiment. The effects of tDCS were most pronounced for participants scoring low on aberrant perceptual beliefs and spiritual transcendence, suggesting a relation between third-person perspective taking and bodily and perceptual experiences. The finding that anodal stimulation of the rTPJ impairs third-person perspective taking indicates a key role of this region in exocentric spatial processing.     

Temporal references in dreams and autobiographical memory

In an attempt to determine whether temporal references identified in dreams follow the same temporal distributions as those documented for autobiographical memories, 28 younger women (18-35 years of age) and 30 older women (60-77 years of age) kept a home dream diary for 1 week and then slept 1 night in the laboratory for rapid eye movement sleep dream collection. The following morning, they identified temporal references in their dreams and produced a sample of autobiographical memories using the semantic cuing method. For both groups, there was a linear decrease in temporal references identified in dreams and autobiographical memories with increased remoteness for the last 30 years. As predicted, for the older group, there were similar cubic trends reflecting a disproportionately higher number of both temporal references identified in dreams and autobiographical memories from adolescence/early adulthood compared with adulthood and childhood. The results support the notion of continuity between waking and dreaming memory processes.     

Correlates of suicide in the older adult population in Quebec

This study was undertaken to describe the characteristics of adults aged 60 years and over who committed suicide in Quebec in 1998-1999. In this study, 42.6% of the suicide cases presented mental disorders at the time of their death, mainly depression. Sixty-five (65.3%) percent of the suicide cases would have been considered as having a mental health disorder if sub-threshold depression cases were included. Only 27.7% of the cases did not express any idea of death during the 6-month period preceding their suicide. One interesting finding was that 53.5% of the suicide cases consulted a general practitioner or specialist during the 2-week period preceding their death. Our results showed that only 8.1% had a severe level of functional limitations at the time of their death. This result leads us to interpret with caution the conclusion of some studies suggesting that physical frailty is a major causal factor associated with suicide among the elderly.     

Learning in a unidimensional absolute identification task

We tested whether there is long-term learning in the absolute identification of line lengths. Line lengths are unidimensional stimuli, and there is a common belief that learning of these stimuli quickly reaches a low-level asymptote of about seven items and progresses no more. We show that this is not the case. Our participants served in a 1.5-h session each day for over a week. Although they did not achieve perfect performance, they continued to improve day by day throughout the week and eventually learned to distinguish between 12 and 20 line lengths. These results are in contrast to common characterizations of learning in absolute identification tasks with unidimensional stimuli. We suggest that this learning reflects improvement in short-term processing.     

Wading through the stereotypes: positive and negative associations between media use and black adolescents' conceptions of self

Although concern is often expressed that frequent media exposure may adversely affect the self-esteem and racial self-esteem of African American youths, evidence to support this assumption has been limited. To examine this issue, the author collected data among 156 African American high school students, testing connections among racial self-esteem, three dimensions of self-esteem, and multiple forms of media use. Whereas initial comparisons revealed media use to be a negative correlate of self-esteem, further analysis demonstrated that this association varied depending on the media genre and the domain of self in question, the content of students' media diets, and the individual characteristics of the viewer. In addition, both stronger identification with popular Black characters and greater religiosity emerged as possible protective factors.     

Knockdown of Nurr1 in the rat hippocampus: implications to spatial discrimination learning and memory

Nurr1 expression is up-regulated in the brain following associative learning experiences, but its relevance to cognitive processes remains unclear. In these studies, rats initially received bilateral hippocampal infusions of control or antisense oligodeoxynucleotides (ODNs) 1 h prior to training in a holeboard spatial discrimination task. Such pre-training infusions of nurr1 antisense ODNs caused a moderate effect in learning the task and also impaired LTM tested 7 d later. In a second experiment, ODN infusions were given immediately after the animals had received two sessions of training, during which all animals showed normal learning. Although antisense treated rats were significantly impaired during the post-infusion stages of acquisition of the task, no group differences were observed during the LTM test given 7 d later. These animals were subjected 3 d later to reversal training in the same maze in the absence of any additional treatments. Remarkably, rats previously treated with antisense ODNs displayed perseveration: The animals were fixated with the previously learned pattern of baited holes, causing them to be significantly impaired in the extinction of acquired spatial preferences and future learning. We postulate that Nurr1 function in the hippocampus is important for normal cognitive processes.     

The relationship between the quality of cooperative learning, students' goal preferences, and perceptions of contextual factors in the classroom

This study examined relationships between the quality of cooperative learning (CL) and students' goal preferences and perceptions of contextual factors in the classroom. Subjects were 1,920 students in secondary vocational schools. The study focused on four different types of goals: social support, belongingness, mastery, and superiority goals. It was found that social support goals had the strongest relation with the quality of CL. Further we found that the quality of CL was best predicted by a combination of social support goals, evaluations of the extent that students were taught cooperation skills, perception of teacher monitoring behavior, and the availability of academic and emotional peer support. Female students' preferences for mastery and social goals were stronger than those of male students, whereas male students had a stronger preference for superiority goals. Program type functioned as a moderator variable within the relation of students' superiority/ individuality goals and the quality of CL.     

The stress and coping questionnaire for children (school version and asthma version): construction,factor structure,and psychometric properties

Based on Lazarus and Folkman's 1984 Stress-Coping Model, a self-report measure for children between 8 and 12 years of age was constructed. It is called the Stress and Coping Questionnaire for Children (School version and Asthma version) and measures children's emotional responses and coping strategies when they confront school-related and asthma-related stressors. The factor structure of this questionnaire was assessed and cross-validated in two samples, one of 392 primary school children without a chronic disease and one of 119 children with asthma. Five scales of coping strategies with regard to two school-related stressors and one asthma-related stressor were distinguished in a reliable way, Approach, Avoidance, Seeking Social Support, Aggression, and Crying.