30 research outputs found
Sleep and psychological factors are associated with meeting discharge criteria to return to sport following ACL reconstruction in athletes
INTRODUCTION: This study aimed to determine if sleep quality and psychological factors were associated with time to meet the discharge criteria to return to sport (RTS) following anterior cruciate ligament reconstruction (ACL-R) among athletes experiencing better quality of sleep and psychological responses returning faster to full activity.
METHOD: A cohort-study design included 89 athletes following ACL-R. Each participant completed a battery of questionnaires at 6 different time points: within 3 days of injury occurrence and at post-surgery (1.5m, 3m, 4.5m, 6m and when discharge criteria were met). Assessment included sleep quality and quantity, symptoms of depression, anxiety, stress, psychological readiness to RTS and fear of re-injury. The primary outcome was the time needed to meet all discharge criteria to RTS.
RESULTS: Sleep parameters and psychological factors were not associated with time to meet the discharge criteria to RTS. However, athletes that had low anxiety and insomnia scores at baseline and better sleep quality at 3m, 4.5m, 6m and at discharge were more adherent to the rehabilitation program and more likely to meet the RTS discharge criteria OR 1.2 (95% CI 1.0-1.34), 1.3 (95% CI 1.1, 1.7) and 2.0 (95% CI 1.1-3.4) respectively.
CONCLUSIONS: Sleep quality and psychological factors were not associated with time to meet the discharge criteria to RTS but impacted whether athletes adhered and completed their rehabilitation program or not. Monitoring sleep quality and psychological factors of athletes before and following ACL-R surgery is important to identify athletes who could have difficulties in adhering to and completing their rehabilitation program to RTS
Alterations in cognitive performance during passive hyperthermia are task dependent
The objectives of this study were to (1) assess the effect of passive heating upon attention and memory task performance, and (2) evaluate the effectiveness of the application of cold packs to the head on preserving these functions. Using a counterbalance design 16 subjects underwent three trials: a control (CON, 20°C, 40% rH), hot (HOT, 50°C, 50% rH) and hot with the head kept cool (HHC). In each condition, three attention tests and two memory tests were performed. Mean core, forehead and tympanic temperatures were all significantly higher (p< 0.05) during HOT (38.6° ±0.1°, 39.6° ±0.2° and 38.8°±0.1°C, respectively) and HHC (38°±0.2, 37.7°±0.3° and 37.7°C, respectively) than in CON (37.1°±0.6°, 33.3° ±0.2° and 35.9°±0.3°C, respectively). Results indicate that there was impairment in working memory with heat exposure (p < 0.05) without alteration in attentional processes. The regular application of cold packs only prevented the detrimental effect of hyperthermia on short-term memory. Our results show that impairments in cognitive function with passive hyperthermia and the beneficial effect of head cooling are task dependent and suggests that exposure to a hot environment is a competing variable to the cognitive processes
Motivational control over well-trained performance.
International audienc
Ătude au moyen des potentiels Ă©voquĂ©s tardifs de l'organisation des Ă©tapes sensorimotrices chez l'homme
National audienceThe main aim of this study was to test the relative organization of three of the stages of Sanders' 1990 information processing mode1: âfeatures extractionâ, âresponse choiceâ, and âmotor adjustementâ. The variables influencing these stages: stimulus degradation, stimulus-response (SR) compatibility and preparatory period have been manipulated. Event related potentials (N100, N200, P300) and reaction time were recorded from ten healthy subjects, in a dichotic listening task. Reaction times are lengthened for degraded stimuli, in the absence of a preparatory period and for SR non compatible conditions. However, the interaction between preparatory period and stimulus degradation variables, suggests an overlaping of the corresponding stages contrary to Sanders' postulate. The non compatible condition increases the latency of N200 and P300 components. The results suggest that the response choice processing would be contemporary to the N200 component. They are discussed within the framework of models of early communication between sensory and motor systems.L'objectif de l'Ă©tude consistait Ă tester l'organisation de trois Ă©tapes du modĂšle de traitement de l'information proposĂ© par Sanders en 1990: âȘl'extraction des caractĂ©ristiques du stimulusâ«, âȘle choix de la rĂ©ponseâ« et âȘl'ajustement moteurâ«. Les variables agissant sur ces Ă©tapes: dĂ©gradation du stimulus, compatibilitĂ© stimulus-rĂ©ponse (SR) et pĂ©riode prĂ©paratoire, ont Ă©tĂ© manipulĂ©es. Les composantes des potentiels Ă©voquĂ©s (N100, N200, P300) et le temps de rĂ©action ont Ă©tĂ© enregistrĂ©s chez dix sujets sains, au cours d'une tĂąche d'Ă©coute dichotique. Les temps de rĂ©action sont allongĂ©s pour les stimulus dĂ©gradĂ©s, en l'absence de pĂ©riode prĂ©paratoire et dans les conditions d'incompatibilitĂ©. Les effets de la pĂ©riode prĂ©paratoire et de la dĂ©gradation du stimulus inter-rĂ©agissent, suggĂ©rant, un chevauchement des Ă©tapes correspondant contrairement au postulat dĂ©fendu par Sanders. La condition d'incompatibilitĂ© allonge les latences des composantes N200 et P300. Les rĂ©sultats suggĂšrent que le choix de la rĂ©ponse est contemporain de la composante N200. Ils sont discutĂ©s dans le cadre des modĂšles proposant une communication prĂ©coce entre les systĂšmes sensoriels et moteurs
Event-Related Potentials in Parkinsonâs Disease: A Review
This article reviews the findings of event-related potentials (ERP) in Parkinson's disease (PD) published during the last 10 years. Basic principles and methods of ERP are briefly presented with particular regard to the auditory âodd-ballâ paradigm almost uniquely employed for the ERP assessment in PD to date. The results of respective studies are overviewed and discussed with respect to three main axes: (1) The slowing down of cognitive processing in PD is reflected by the delays of N2 and P3 components of ERP which are more important in demented than in non-demented patients. The Nl component is delayed in demented patients with PD as well as in other dementias of presumed subcortical origin. (2) Various neuropsychological deficits observed in PD correlate with the delays of ERP evoking the implication of common subcortico-cortical cerebral mechanisms. (3) The variations of ERP under dopaminergic manipulation suggest conflicting effects of levodopa treatment on cognition, at least in certain categories of PD patients. These findings are discussed in the light of current knowledge on neurotransmitter brain systems and some hypothetic explanations are proposed. Finally, an attempt is made to outline further perspectives of clinical and research utilization of ERP in Parkinson's disease
Des neurosciences Ă la gestion du stress devant lâassiette
Le stress est au centre de la psychopathologie et notamment des troubles du
comportement alimentaire : il est Ă la fois symptĂŽme et cause de nombreux
dysfonctionnements cognitifs ou comportementaux et constitue un facteur
pathogÚne somatique majeur. Or la présente étude montre que le niveau de stress
semble Ă©troitement liĂ© aux dysfonctionnements dâune bascule entre deux grands
modes du fonctionnement mental supérieur (automatique versus adaptatif), dont
les substrats neurobiologiques ont été mis en évidence en Imagerie par Résonance
MagnĂ©tique fonctionnelle (IRMf). Elle expose tout dâabord les caractĂ©ristiques
cognitives liées aux deux modes de fonctionnement considérés : un mode
automatique de fonctionnement apparaßt adapté lors de situations simples et
routiniÚres, tandis que le mode adaptatif ou préfrontal est approprié aux
situations complexes et/ou inconnues. LâĂ©tude met donc en Ă©vidence, au travers
de ses premiers résultats, le lien entre la persistance inadaptée du mode de
fonctionnement dit automatique en situation de non contrĂŽle (complexe et/ou
inconnue) et lâapparition dâun Ă©tat de stress. Elle prĂ©sente enïŹn les rĂ©sultats
dâune gestion cognitive des modes mentaux considĂ©rĂ©s sur le niveau de stress.
Les premiers rĂ©sultats de cette Ă©tude esquissent les contours dâune thĂ©rapie
neurocognitive du stress, sâintĂ©ressant plus au contenant cĂ©rĂ©bral quâau contenu
cognitif
Effect of passive hyperthermia on working memory resources during simple and complex cognitive tasks
The aim of this study was to verify the hypothesis that hyperthermia represents a cognitive load limiting available resources for executing concurrent cognitive tasks. Electroencephalographic activity (EEG: alpha and theta power) was obtained in 10 hyperthermic participants in HOT (50°C, 50% RH) conditions and in a normothermic state in CON (25°C, 50% RH) conditions in counterbalanced order. In each trial, EEG was measured over the frontal lobe prior to task engagement in each condition (PRE) and during simple (OTS-4) and complex (OTS-6) cognitive tasks. Core (39.5 ± 0.5 vs. 36.9 ± 0.2ÂșC) and mean skin (39.06 ± 0.3 vs. 31.6 ± 0.6ÂșC) temperatures were significantly higher in HOT than CON (P<0.005). Theta power significantly increased with task demand (p=0.017, η2=0.36) and was significantly higher in HOT than CON (p=0.041, η2=0.39). The difference between HOT and CON was large (η2=0.40) and significant (p=0.036) PRE, large (η2=0.20) but not significant (p=0.17) during OTS-4, and disappeared during OTS-6 (p=0.87, η2=0.00). Those changes in theta power suggest that hyperthermia may act as an additional cognitive load. However, this load disappeared during OTS-6 together with an impaired performance, suggesting a potential saturation of the available resources