Evaluating the coordination dynamics of handwriting

This study aims to test the hypothesis that handwriting is governed by the dynamics of non-linear coupled oscillators. Accordingly, its first goal is to identify preferred, basic graphic shapes corresponding to spontaneously stable combinations of the two frequency-locked oscillatory x-y components of the trajectories. Six participants were required to produce 26 ellipsoids of varying eccentricities and orientations presented consecutively on a graphic tablet. These shapes corresponded to a systematic manipulation of the relative phase and the relative amplitude of the oscillators by a constant step. Results showed that among those, only eight ellipsoids were produced in a spontaneous and stable fashion. They were characterized by attraction of nearby shapes, and by a higher accuracy and velocity. Alike all periodic motion, graphic skills, hence handwriting, exhibit preferred coordination patterns, which can be ascribed to the non-linear coupling of two oscillators.     

Evening and morning EEG differences between young men and women adults

Evening and morning waking EEG (eyes closed) was recorded in 16 women and 13 men aged 18-26 years old. Participants were fitted with a 13-electrode montage (Fp1, Fp2, FZ, F7, F8, C3, C4, T3, T4, P3, P4, O1, and O2) referred to linked ears. For each recording electrode, EEG total spectral amplitude power (microV/Hz, 0.75-19.75 Hz) was compared using 2 (Gender) x 2 (Moments) analyses of variance for repeated measures and LSD post-hoc tests. We found significant simple Gender effects, with women displaying higher EEG values for Central, Frontal, Parietal, and left Temporal leads. Simple Moment effects were also found, with lower morning values in Temporal and left Frontal recording sites. A Gender x Moment interaction was found at the right Frontal recording site. No significant effects were found for Prefrontal and Occipital recording sites, whatsoever. These results bring new understandings of gender and time of day effects in waking EEG and point to different sensitivity in different cortical areas. The present results could explain some of the observations related to gender differences in cognitive performance.     

Selective attention, inhibition for repeated events and hemispheric specialization

When two visual events appear consecutively in the same spatial location, our response to the second event is slower than to the first. This inhibition for repeated events may reflect a bias toward sampling novel locations, a bias useful for exploring visual space. It has been shown that the left hemisphere is more specialized in selective attentional processes than the right one. The aim of the present experiment was to test if this hemispheric specialization for selective attention may also affect the inhibition for repeated events. For this purpose, we asked 11 normal subjects to perform an identity-based discrimination task in which the target to be detected could appear alone or surrounded by flanking letters, in the left or in the right visual field. Results show that inhibition for repeated events is present only when selective attention is required and when the task is performed in the right specialized visual field.     

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...     

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.