Hemispheric specialization for spatial frequency processing in the analysis of natural scenes

Experimental data coming from visual cognitive sciences suggest that visual analysis starts with a parallel extraction of different visual attributes at different scales/frequencies. Neuropsychological and functional imagery data have suggested that each hemisphere (at the level of temporo-parietal junctions-TPJ) could play a key role in spatial frequency processing: The right TPJ should predominantly be involved in low spatial frequency (LFs) analysis and the left TPJ in high spatial frequency (HFs) analysis. Nevertheless, this functional hypothesis had been inferred from data obtained when using the hierarchical form paradigm, without any explicit spatial frequency manipulation per se. The aims of this research are (i) to investigate, in healthy subjects, the hemispheric asymmetry hypothesis with an explicit manipulation of spatial frequencies of natural scenes and (ii) to examine whether the 'precedence effect' (the relative rapidity of LFs and HFs processing) depends on the visual field of scene presentation or not. For this purpose, participants were to identify either non-filtered or LFs and HFs filtered target scene displayed either in the left, central, or right visual field. Results showed a hemispheric specialization for spatial frequency processing and different 'precedence effects' depending on the visual field of presentation.     

Monoparentalité et santé: Problèmes de santé et mobilisation de ressources d'assistance suite à la désunion

A partir d'une enquête auprès d'un échantillon représentatif de chefs de foyers monoparentaux québécois, le présent article étudie les interrelations entre les problèmes de santé vécus par les membres de l'unité familiale, la mobilisation des ressources d'assistance et la perception qu'ont les parents gardiens du réseau de la santé, ainsi que de l'aide étatique qui leur est dispensée. La mésentente parentale au moment de la rupture est associée aux problèmes psychologiques vécus par le parent gardien et les enfants, et pourrait engendrer des problèmes pour lesquels les parents ne trouvent pas réponse dans les réseaux formels d'assistance. Les parents qui ont peu bénéficié de l'aide des réseaux informels se montrent plus critiques vis-à-vis de l'assistance de l'État. Des comparaisons sont effectuées selon le sexe et la langue d'usage du parent gardien.     

Six Years in the Cognitive and Metacognitive Life of 71 Families

Seventy-one families from a low socio-economic background, each with a son at risk of developing psychosocial problems at the onset of the study, were observed three times over a six-year period while solving a combinatorial task presented on a microcomputer. The permutations task was used to gather information with regard to cognitive functioning and cognitive self-regulation of the families, which were observed as a developmental unit. Cognitive functioning was assessed according to three variables: cognitive strategies, performance, and completion of the task. Six self-regulatory activities were assessed: task definition, planning, supervision, evaluation, parental support, and sharing of responsibilities. Although inefficient strategies were mainly used across the six years, the cognitive level of functioning improved over the years. Cognitive self-regulatory activities most often used across time were supervision and parental support. Differences were observed in the three time periods for supervision, task definition, parental support, and individual involvement. Results indicated a link between cognitive strategies used by the families to solve the task and their self-regulatory activities. Results are interpreted within both the Piagetian and Vygotskian perspectives. Families' cognitive self-regulatory activities observed in this study are an example of parental disengagement and children's growing involvement in a joint activity.     

Questions of times: Conflicting time scales in historical perspective

The idea of ``Jewish' time highlights many problems related to the conflict between Judaism and Christianity. This paper focuses on two points: the reckoning of the Jewish era and the interpretation of the notion of time in the Bible. Jewish time pulsates to a rhythm of temporal markers which also divide it into secular and religious time. This division, however, this dual register of temporality, also enables Jews to alternate a ``Jewish' register with a ``universal' one. Traditional Jewish sources indicate that the principle of determining the date by calculating from the creation of the world (anno mundi) appeared during the period of the Second Temple. The question of elapsed time, deduced from different readings of the Biblical text, launched Jews and Christians on parallel lines of time. The history of the genesis of the notion of time asserts that the circular representation of temporality, sometimes called indigenous to ancient societies, was replaced by a representation that was vertical, then linear. These stages served as a scale for measuring the progress and evolution of societies. The Christian notion was supposed to characterize European time as an ``infinite line' along which events are placed, in contrast to Israelite time, identifiable through its contents, and in which time is ``full' and concrete, with no room for (re)ordering or arranging its episodes. This revised version was published online in August 2006 with corrections to the Cover Date.     

Behavioral and Psychological Symptoms that Predict Cognitive Decline or Impairment in Cognitively Normal Middle-Aged or Older Adults: a Meta-Analysis

Neuropsychology Review - Epidemiological studies have revealed that behavioral and psychological (or non-cognitive) symptoms are risk factors for cognitive decline in older adults. This study aimed...     

A Test of the Links between Family Interference with Work, Job Enrichment and Leader–Member Exchange

Nous avons testé l'hypothèse selon laquelle le degré d'interférence entre la vie familiale et le travail (FIW) chez des sujets "suiveurs" varie en fonction de la qualité de la relation leader-suiveur dans le monde du travail (Qualité LMX) et de leur niveau de valorisation du travail. La relation entre ce niveau et la qualité LMX a aussi étéévaluée. Si le FIW, en accord avec les résultats relatifs à la théorie de l'échange social, est lié négativement, et à la qualité LMX, et au niveau de valorisation du travail des suiveurs, ce dernier est corrélé positivement à la qualité LMX conformément aux prédictions principales de la théorie LMX. Cependant, bien que le FIW se rapporte directement au niveau de valorisation du travail, nous avons pu montrer qu'il est lié indirectement à la qualité LMX par le truchement du niveau de valorisation du travail.
We tested whether followers' frequency of family interference with work (FIW) relates to the quality of the leader–follower work relationship (LMX quality), and to followers' reported level of job enrichment. We also tested the relationship between followers' job enrichment and LMX quality. We found that that FIW relates negatively to LMX quality and to job enrichment, supporting arguments based on social exchange theory, and that followers' job enrichment relates positively to LMX quality, supporting one of the key predictions of LMX theory. We also found that while FIW relates directly to job enrichment, it relates only indirectly to LMX quality through job enrichment.     

Detection of metric structure in auditory figural patterns

This series of experiments dealt with discrimination between two temporal patterns differing only by the insertion of an additional silent gap. In Experiment 1, patterns varied in metric and figural structure. Metric structure is described as the sense of temporal regularity that may occur between subjectively accented tones. Figural structure is described as the grouping of temporally adjacent tones separated by silences. Standard patterns were either strongly or weakly metric; comparison patterns differed from the standards by the insertion of a silence that disrupted either the metric structure alone or both the metric and the figural structures. Experiment 1 provided support for the roles of both metric and figural structures and provided support for the clock-induction model of Povel and Essens (1985) as an account of metric processing. In Experiments 2-4, discrimination of patterns with differing metric structures but identical figural structures was examined more closely. Rate of presentation of the patterns was varied. Multiple regression indicated that, independent of rate variations, discrimination improved as the absolute (not relative) duration of the silent gap increased. We argue that an additional timing mechanism, independent of pattern structure, is operative in temporal pattern discrimination. All the results were replicated across levels of music training of the listeners.     

Short-term memory for time in children and adults: A behavioral study and a model

This experiment investigated the effect of the short-term retention of duration on temporal discrimination in 5- and 8-year-olds, as well as in adults, by using an episodic temporal generalization task. In each age group, the participants' task was to compare two successive durations (a standard and a comparison duration) separated by a retention interval of 500ms, 5s, or 10s, with the order of presentation of these two durations being counterbalanced. The results revealed a shortening effect for the first presented stimulus in all of the age groups, although this was greater in the younger children, thereby indicating the presence of a negative time-order error. Furthermore, introducing a retention delay between the two durations did not produce a shortening effect but instead flattened the generalization gradient, especially in the younger children. However, this flattening of the generalization gradient with the retention delay was more marked between 500ms and 5s than between 5s and 10s. Thus, retaining the first duration in short-term memory during a task requiring the comparison of two successive durations reduced temporal discrimination accuracy and did so to a greater extent in the younger children.     

Transtheoretical model and condom use in HIV-positive youths.

The purpose of the study is to test constructs of the Transtheoretical Model for predicting unprotected intercourse in HIV-positive youths (ages 16-25 years). Questionnaires and interviews about sexual behavior, stage of change, self-efficacy, substance use, emotional distress, and social support were obtained from 60 HIV-positive youths. Path analysis, with standard errors determined by methods appropriate to small samples, suggested that self-efficacy completely mediated the relationship between stage of change and unprotected intercourse acts. Social support specific to reducing risk was associated with increased self-efficacy. Emotional distress and low general social support were not associated with decreased condom use. The path between substance use and decreased condom use approached significance. Results highlight the potential of prevention interventions that simultaneously boost self-efficacy and social support specific to practicing safer sex as well as those that reduce substance use.