Distance Learning University

Brig, Switzerland

Distance Learning University

Brig, Switzerland

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Tipura E.,University of Geneva | Tipura E.,Distance Learning University | Pegna A.J.,University of Queensland | Pegna A.J.,University of Geneva | And 2 more authors.
Clinical Neurophysiology | Year: 2017

Objective We investigated neuronal correlates of faces versus non-faces processing in a cortically blind patient (TN) and a group of healthy age-matched controls in order to test electrophysiological correlates of the processing of pertinent stimuli in this patient. Methods An EEG paradigm was used, in which intact and scrambled faces were displayed on a screen. First, time-frequency transforms were conducted on the patients’ data alone. These oscillations were then compared to the frontal activity of six control participants. Results Post stimulus oscillatory modulations (synchronisation in theta and alpha frequency bands) of both intact and scrambled faces at frontal scalp sites were observed in TN. These modulations were different for correct and incorrect responses. A more important increase in the theta band for incorrect responses was observed. The oscillatory rhythms highlighted in blindsight and in frontal regions differ from the ones observed in control participants. Conclusion Despite the destruction of the visual cortex, oscillatory rhythms are not cancelled out but are shifted to anterior regions, revealing the activity of an alternate pathway for residual visual function. Significance The results provide evidence for a top-down cognitive control process in blindsight. © 2017 International Federation of Clinical Neurophysiology

Ghisletta P.,University of Geneva | Ghisletta P.,Distance Learning University | Kennedy K.M.,University of Texas at Dallas | Rodrigue K.M.,University of Texas at Dallas | And 2 more authors.
Journals of Gerontology - Series B Psychological Sciences and Social Sciences | Year: 2010

The effects of advanced age and cognitive resources on the course of skill acquisition are unclear, and discrepancies among studies may reflect limitations of data analytic approaches. We applied a multilevel negative exponential model to skill acquisition data from 80 trials (four 20-trial blocks) of a pursuit rotor task administered to healthy adults (19-80 years old). The analyses conducted at the single-trial level indicated that the negative exponential function described performance well. Learning parameters correlated with measures of task-relevant cognitive resources on all blocks except the last and with age on all blocks after the second. Thus, age differences in motor skill acquisition may evolve in 2 phases: In the first, age differences are collinear with individual differences in task-relevant cognitive resources; in the second, age differences orthogonal to these resources emerge.

Ghisletta P.,University of Geneva | Ghisletta P.,Distance Learning University | Backman L.,Karolinska Institutet | Bertram L.,Max Planck Institute for Molecular Genetics | And 6 more authors.
Psychology and Aging | Year: 2014

The brain-derived neurotrophic factor (BDNF) promotes activity-dependent synaptic plasticity, and contributes to learning and memory. We investigated whether a common Val66Met missense polymorphism (rs6265) of the BDNF gene is associated with individual differences in cognitive decline (marked by perceptual speed) in old age. A total of 376 participants of the Berlin Aging Study, with a mean age of 83.9 years at first occasion, were assessed longitudinally up to 11 times across more than 13 years on the Digit-Letter task. Met carriers (n = 123, 34%) showed steeper linear decline than Val homozygotes (n = 239, 66%); the corresponding contrast explained 2.20% of the variance in change in the entire sample, and 3.41% after excluding individuals at risk for dementia. These effects were not moderated by sex or socioeconomic status. Results are consistent with the hypothesis that normal aging magnifies the effects of common genetic variation on cognitive functioning. © 2014 American Psychological Association.

Chanal J.,University of Geneva | Chanal J.,Distance Learning University | Guay F.,Laval University
PLoS ONE | Year: 2015

This research sought to test whether autonomous and controlled motivations are specific to school subjects or more general to the school context. In two cross-sectional studies, 252 elementary school children (43.7% male; mean age = 10.7 years, SD = 1.3 years) and 334 junior high school children (49.7% male, mean age = 14.07 years, SD = 1.01 years) were administered a questionnaire assessing their motivation for various school subjects. Results based on structural equation modeling using the correlated trait-correlated method minus one model (CTCM-1) showed that autonomous and controlled motivations assessed at the school subject level are not equally school-subject-specific. We found larger specificity effects for autonomous (intrinsic and identified) than for controlled (introjected and external) motivation. In both studies, results of factor loadings and the correlations with selfconcept and achievement demonstrated that more evidence of specificity was obtained for autonomous regulations than for controlled ones. These findings suggest a new understanding of the hierarchical and multidimensional academic structure of autonomous and controlled motivations and of the mechanisms involved in the development of types of regulations for school subjects. Copyright: © 2015 Chanal, Guay.

Cheval B.,University of Geneva | Courvoisier D.S.,University of Geneva | Chanal J.,University of Geneva | Chanal J.,Distance Learning University
Preventive Medicine | Year: 2016

Objective: Physical education (PE) during school provides an opportunity for children to be physically active. Few empirical studies have investigated developmental trajectories and determinants of objective moderate to vigorous physical activity (MVPA) during PE classes. The purpose of this study was to examine the developmental trajectories and determinants of MVPA during PE lessons in young children (8-12 years of age) in primary schools. Methods: Students in grades 5-7 (n = 1202; 51.2% girls) were recruited from 17 elementary schools from the Geneva canton in 2012-2013. The percentage of time spent in accelerometer-assessed MVPA during regular PE lessons was used as a dependent variable. Results: Linear mixed-model analyses revealed (a) that boys had a higher percentage of MVPA than girls, but none of the children reached the recommended activity levels (i.e., 50% of the PE class time spent in MVPA), (b) a linear decrease in the percentage of MVPA with age, (c) that higher perceived competence predicted a higher percentage of MVPA, and (d) that higher perceived competence reduced the negative linear effect of age among boys, but not among girls. Conclusion: The percentage of PE time spent in MVPA did not reach recommendations made by Centers for Disease Control and Prevention and decreased from 8 to 12 years old both for boys and girls. Perceived competence appears crucial to reduce MVPA decline for boys, but not for girls. © 2016 Elsevier Inc.

Golay P.,University of Geneva | Golay P.,Distance Learning University | Reverte I.,University of Geneva | Rossier J.,University of Lausanne | And 4 more authors.
Psychological Assessment | Year: 2013

The interpretation of the Wechsler Intelligence Scale for Children-Fourth Edition (WISC-IV) is based on a 4-factor model, which is only partially compatible with the mainstream Cattell-Horn-Carroll (CHC) model of intelligence measurement. The structure of cognitive batteries is frequently analyzed via exploratory factor analysis and/or confirmatory factor analysis. With classical confirmatory factor analysis, almost all crossloadings between latent variables and measures are fixed to zero in order to allow the model to be identified. However, inappropriate zero cross-loadings can contribute to poor model fit, distorted factors, and biased factor correlations; most important, they do not necessarily faithfully reflect theory. To deal with these methodological and theoretical limitations, we used a new statistical approach, Bayesian structural equation modeling (BSEM), among a sample of 249 French-speaking Swiss children (8-12 years). With BSEM, zero-fixed cross-loadings between latent variables and measures are replaced by approximate zeros, based on informative, small-variance priors. Results indicated that a direct hierarchical CHC-based model with 5 factors plus a general intelligence factor better represented the structure of the WISC-IV than did the 4-factor structure and the higher order models. Because a direct hierarchical CHC model was more adequate, it was concluded that the general factor should be considered as a breadth rather than a superordinate factor. Because it was possible for us to estimate the influence of each of the latent variables on the 15 subtest scores, BSEM allowed improvement of the understanding of the structure of intelligence tests and the clinical interpretation of the subtest scores. © 2012 American Psychological Association.

Borella E.,University of Padua | Ghisletta P.,University of Geneva | Ghisletta P.,Distance Learning University | De Ribaupierre A.,University of Geneva
Journals of Gerontology - Series B Psychological Sciences and Social Sciences | Year: 2011

Objectives. Age-related changes in the efficiency of various general cognitive mechanisms have been evoked to account for age-related differences between young and older adults in text comprehension performance. Using structural equation modeling, we investigate the relationship between age, working memory (WM), inhibition-related mechanisms, processing speed, and text comprehension, focusing on surface and text-based levels of processing. Methods. Eighty-nine younger (M = 23.11 years) and 102 older (M = 70.50 years) adults were presented text comprehension, WM, inhibition, and processing speed tasks. In the text comprehension task, the demand on the memory system was manipulated, by allowing (text present) or not (text absent) viewing the text during the answering phase. Results. As expected, age differences were larger when the text was absent. The best fitting model showed that WM mediated the influence of age on both text processing conditions, whereas age-related variance in WM was, in turn, accounted for by processing speed and inhibition. Discussion. These findings confirm the hypothesis that WM capacity explains age differences in text processing, while it is itself accounted for by the efficiency of inhibiting irrelevant information and by speed of processing. © The Author 2011.

Aibar A.,University of Geneva | Chanal J.,University of Geneva | Chanal J.,Distance Learning University
PLoS ONE | Year: 2015

Background Despite a consensus emerging that affirms that shorter epochs should be used in youth to correctly register physical activity levels in free-living conditions, little is known about its effect on children's physical activity conducted in structured periods of time. This study analyzed the effect that epoch length (1, 2, 3, 5, 10, 15, 30 and 60s) may have on different physical activity intensities in physical education lessons. Methods A sample of 1912 individualmeasures of physical education lessons were measured with a GT3X accelerometer. Data were collected from 1227 Swiss Elementary school students recruited in 17 elementary schools. PE lessons lasted from 45 minutes to one and a half hours. Data, originally collected in 1-s epoch, were then reintegrated into 2s, - 3s - 5s - 10s - 15s - 30s -60s epochs. Results Longer epochs were associated with higher levels of light (F = 8197.6, p < .001), moderate (F = 2708.17, p < .001), and moderate-to-vigorous physical activity (F = 888.08, p < .001). However, longer epochs showed lower levels of sedentary activity (F = 31714.33, p < .001) and vigorous physical activity (F = 1910.97, p < .001). Bias increased in all PA intensities when shorter epochs were compared with longer epochs. There were statistically significant differences in compliance with physical education guidelines (χ2 = 989.27, p<.001), showing higher levels with longer epochs. Conclusion PA context may have some influence on the effects that epoch length have on PA estimates, more specifically on MVPA. Nevertheless, the use of a high-frequency sampling interval should be used to more accurately assess children's PA. Copyright: © 2015 Aibar, Chanal.

Luszcz M.A.,Flinders University | Anstey K.J.,Australian National University | Ghisletta P.,University of Geneva | Ghisletta P.,Distance Learning University
Gerontology | Year: 2015

Background: Neither subjective memory beliefs, nor remembering itself, can be isolated from the overall context in which one is aging, nor are the drivers of memory complaints well specified. Sense of control is an important self-regulatory resource that drives cognitive and physical health over the lifespan. Existing findings are equivocal concerning both the extent of stability or change in control beliefs over time as well as their contribution to changes in behavior. Objective: Subjective beliefs may play a role when engaging memory processes or identifying memory complaints, and it has been argued that self-regulatory potential in general may be limited by age-related changes in the domains of health and cognition. We aimed to examine trajectories of change and shed light on relationships among subjective beliefs and indicators of memory and functional health. Methods: Participants' data were drawn from four measurement occasions over up to a 12-year period (1992-2004) from the Australian Longitudinal Study of Ageing (ALSA), a population-based study of older adults [age 65-100 years; mean age(SD) at the first and final occasion 78.2 (6.7) and 84.9 (4.9) years, respectively]. Participants completed three questionnaires assessing subjective beliefs concerning (1) memory knowledge and control, (2) health control, and (3) expectancy of control over a range of lifestyle situations. Memory comprised a recall composite. Functional health tapped mobility and disability. Latent growth curve models incorporated informative covariates (baseline age, gender, self-rated health, education, and chronic conditions). Results: While subjective memory control beliefs, but not subjective knowledge of memory tasks, improved over 12 years, neither was associated with level of memory performance. Knowledge of memory tasks was linked to a significant memory decline. Beliefs about memory, health, and lifestyle were interrelated. Declines in remembering and health were also coupled; moreover, changes in both were coupled with change in lifestyle control beliefs. Conclusions: This is the first examination of individual differences in changes in, and relationships among, psychological domains of subjective beliefs about memory, health, and lifestyle, and objective remembering and functional health in very late life. Findings point to a system of coupled changes in memory and health in late life that is related to underlying beliefs about control over lifestyle. © 2015 S. Karger AG, Basel.

Lindenberger U.,Max Planck Institute for Human Development | Lindenberger U.,Saarland University | von Oertzen T.,Max Planck Institute for Human Development | von Oertzen T.,Saarland University | And 3 more authors.
Psychology and Aging | Year: 2011

In cross-sectional age variance extraction (CAVE), age, the indicator of a hypothesized developmental mechanism, and a developmental outcome are specified as independent, mediator, and target variables, respectively, to test hypotheses about behavioral development. We show that: (a) longitudinal change in a mediator variable accounting for substantial cross-sectional age-related variance in the target variable need not correlate with the target variable's longitudinal change; and, conversely, (b) longitudinal change in a mediator not sharing cross-sectional age-related variance with the target variable may nevertheless correlate highly with that variable's longitudinal change. We discourage use of CAVE for testing multivariate hypotheses about behavioral development. © 2011 American Psychological Association.

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