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Background: Walking while performing a secondary task (dual-task (DT) walking) increases cognitive workload in young adults. To date, few studies have used neurophysiological measures in combination to subjective measures to assess cognitive workload during a walking task. This combined approach can provide more insights into the amount of cognitive resources in relation with the perceived mental effort involving in a walking task. Research Question: The objective was to examine cognitive workload in young adults during walking conditions varying in complexity. Methods: Twenty-five young adults (mean = 24.4 ± 5.4) performed four conditions: (1) usual walking, (2) simple DT walking, (3) complex DT walking and (4) standing while subtracting. During the walking task, mean speed, cadence, stride time, stride length, and their respective coefficient of variation (CV) were recorded. Cognitive workload will be measured through changes in oxy- and deoxy-hemoglobin (ΔHbO2 and ΔHbR) during walking in the dorsolateral prefrontal cortex (DLPFC) and perceived mental demand score from NASA-TLX questionnaire. Results: In young adults, ΔHbO2 in the DLPFC increased from usual walking to both DT walking conditions and standing while subtracting condition. ΔHbO2 did not differ between the simple and complex DT and between the complex DT and standing while subtracting condition. Perceived mental demand gradually increased with walking task complexity. As expected, all mean values of gait parameters were altered according to task complexity. CV of speed, cadence and stride time were significantly higher during DT walking conditions than during usual walking whereas CV of stride length was only higher during complex DT walking than during usual walking. Significance: Young adults had greater cognitive workload in the two DT walking conditions compared to usual walking. However, only the mental demand score from NASA-TLX questionnaire discriminated simple from complex DT walking. Subjective measure provides complementary information to objective one on changes in cognitive workload during challenging walking tasks in young adults. These results may be useful to improve our understanding of cognitive workload during walking.

11th World Congress for Neurorehabilitation , LYON, FRANCE, 07-/10/2020 - 10/10/2020; Question: Non-pharmacologic treatment such as physical exercise has been proven to have beneficial effects on gait disorders in Parkinson's disease (PD). In Lyon (France), Sirroco rehabilitation program is a novel, collective, multidisciplinary program focused on intensive, high amplitude movements, and loudness of speech for patients with PD. However, the effects of physical exercise on dorsolateral prefrontal cortex (DLPFC) activity in patients with PD is still elusive. The main aim of this pilot study was to assess the effects of the Sirocco program in patients with PD on DLPFC activity on single task (ST) and dual-task (DT) walking. Methods: Fourteen PD patients (mean: 66.9 y.o ± 8.1) completed Sirocco sessions for 5 weeks. Changes in oxyhemoglobin concentration (?HbO2) in the DLPFC were measured using functional Near Infrared Spectroscopy during three walking tasks conditions: (1) ST walking, (2) DT walking while counting forward and (3) DT walking while subtracting. Participants were assessed three times: five weeks before the program (T0); few days before (T1) and one week after the program (T2). Walking performance (mean stride time and cadence) was also recorded using foot-sensors. The gain in performance was calculated by subtracting values at T0 and T1 or at T2 and at T1. Results: Significant differences were observed in ?HbO2 between the three times only for the ST walking: ?HbO2 were significantly higher at T1 than at T0 whereas ?HbO2 was lower in T2 than in T1 (p

WCNR, 11th World Congress for Neurorehabilitation, Lyon, FRANCE, 07-/10/2020 - 11/10/2020; 1.Question: Patients with Parkinson disease (PD) report difficulties walking while performing another task. Dual-task (DT) walking may therefore increase the risk of falls. To date, the effect of DT walking on brain activity is not well understood. The objective of this pilot study was to examine dorsolateral prefrontal cortex activity (DLPFC) during single-task (ST) and DT walking conditions in PD patients. 2.Methods: Thirteen patients with PD (mean age: 66 ± 7 years, 8 men, UPDRS motor score (/108): 23 ± 11, Montreal Cognitive Assessment (MoCA) score: 27 ± 2) and 13 healthy older adults (mean age: 64 ± 7 years, 8 men, MoCA score: 28 ± 3) performed three walking tasks: [1] ST walking, [2] DT walking while counting forward (+1) and [3] DT walking while subtracting (-7). Cortical activity in DLPFC, assessed by changes in oxy-haemoglobin (?HbO2) was measured using functional near infrared spectroscopy (NIRSport). Gait performance (speed, cadence and stride length) was recorded simultaneously using wearables sensors (Gait-Up sensors). 3. Results: In ST walking and DT walking while subtracting conditions, ?HbO2 was higher in patients than in controls (p < 0.05). No significant differences in ?HbO2 were found between ST and the two DT-walking conditions in patients whereas ?HbO2 was significantly higher in DT-walking conditions than in ST walking in controls. As expected, patients had reduced walking speed, cadence and stride length compared to controls, regardless of conditions (p < 0.05). Variability of their cadence increased as the walking task difficulty increased, which is not the case for controls. 4. Conclusion This pilot study suggests that dorsolateral prefrontal cortex plays a major role already during ST walking condition in patients in relatively early stages of PD. This may suggest that patients recruit additional cognitive resources, as a measure of cognitive compensation to perform the ST walking. These findings may have implications for rehabilitation of gait in patients with PD, improving automaticity in simple tasks. Another ongoing study will show the effect of an exercise-based intervention program (SIROCCO program) on DLPFC activity while walking in the same group of patients with PD.

11th World Congress for Neurorehabilitation. 35ème congrès de la SOMFER, LYON, FRANCE, 07-/10/2020 - 10/10/2020; Symposium title: Evidence-Based Practice in Driver Screening, Assessment, and Intervention. The symposium will be a series of short presentations on issues about driving for various neurological conditions. We selected 7 topics selected and identified presenters: Parkinsons - Maud Ranchet 10 minutes MS - Abiodun Akinwuntan 10 minutes Concussion - Hannes 10 minutes TBI - Carol 10 minutes Dementia - Shawn 10 minutes Spinal cord injury - 10 minutes. Presenters will introduce the topic, how it affects driving, screening tools, and management. Each topic has 10 minutes with 20 minutes for questions.

MDS 2019, International Congress of Parkinson's Disease and Movement Disorders , Nice, FRANCE, 22-/09/2019 - 26/09/2019; Objective: To investigate cognitive workload during a visual search task in patients with Parkinson's disease (PD). Background: Visual search is one of the most important features of human activity. Visual search may be impaired in PD, which in turn may negatively affect daily life activities, such as driving. While previous studies explored visual exploration strategies during visual search tasks, no study investigated cognitive workload during visual search in PD. Cognitive workload refers to the total amount of mental effort being used to perform a task. Methods: Twenty patients with PD (age: 69 ± 8 yo; sex (Men/Women): 16/4) and 15 controls (age: 61 ± 11 yo; sex: 8/7) performed a visual search task on a driving simulator, that provides a context similar to visual search during real-life driving. They were instructed to search for a target road sign among distractor road signs. In half of the trials, the target was present (target-present trials). Response times as well as measures of cognitive workload for correct detections trials were investigated in the two groups. Cognitive workload was measured by the Index of Cognitive Activity (ICA), which was based on the number of times per second that an abrupt discontinuity in the pupil signal was detected. To investigate the cognitive workload over time for correct detection trials in the two groups, response time values were transformed to a continuous scale of percentage completion time, ranging from 0 (start of the trial) to 100% (button press) since response times were different between participants. Results: PD patients were significantly slower than controls to respond correctly to the visual search task, particularly for target-present trials. PD patients had increased values in cognitive workload throughout the entire duration of the task when compared to baseline (p < 0.05). By contrast, few significant differences were observed in controls (at 5% and 15%). Conclusions: These findings suggest that PD patients required increased and longer effort to correctly perform the visual search task compared with baseline cognitive workload. The use of ICA in patients with PD while performing a static visual search task provides new information into the effort (cognitive workload) required by patients on a moment-to-moment basis.

Les 31èmes Entretiens Jacques Cartier, Bron, FRANCE, 13-/11/2018 - 14/11/2018; Évaluer les effets d'un programme de rééducation intensive nommé SIROCCO sur les capacités cognitives et motrices. Programme réalisé à l'hôpital Henry Gabrielle, Saint-Genis-Laval. Les premiers résultats comparant les performances de deux patients ayant eu une évaluation avant et après le programme SIROCCO montrent que les capacités motrices liées à la marche sont améliorées.

12th World Congress of the International Society of Physical and Rehabilitation Medicine. Paris. 8-12 July 2018, PARIS, FRANCE, 08-/07/2018 - 12/07/2018; Introduction/Background Evidence suggests that gait in complex situation is influenced by executive function in normal ageing. But to our knowledge, no study revealed what measurement is the most appropriate to assess impaired walking in older adults. The objective is to (1) test the feasibility of our protocol and (2) to explore the cognitive load during a simple vs. dual walking task in younger and older adults. Material and method To date, 6 young adults (mean=26.7 years old; SD=4.1) were included in this study. Fifteen young adults and 25 older adults will be included by May 2018. Participants are asked to achieve a walking task including four conditions: (1) normal pace walking, (2) subtracting while standing, (3) walking while subtracting and (4) walking while counting forward. Cognitive load is measured by changes in oxygenated and deoxygenated hemoglobin in dorsolateral prefrontal cortex (fNIRS device) and the NASA-TLX questionnaire completed after each condition. Results fNIRS analyses are in progress. Preliminary results showed that younger adults felt higher cognitive effort in both conditions 2 and 3 compared to condition 1 (NASAscorescondition2 (mean (SD)): 66 (18.7) vs NASAscorecondtion1: 9.5 (6.3), W=?2.2, P=0.03; NASAscorecondition3: 78 (14.6) vs NASAscorecondition1, W=?2.2, P=0.03). No significant differences in speed, cadence and stride length were found between conditions 1, 3 and 4 (P>0.05). No significant differences in subtraction performances were observed between conditions 2 and 3 (P>0.05). Conclusion Higher cognitive load in condition 3 in younger adults confirm that our dual task walking is the most cognitively demanding condition. We expect that our fNIRS results in younger adults will be similar to those observed with NASA-TLX questionnaire. However, discrepancies between those two measures are expected in older adults.

38ème Congrès annuel des hôpitaux de jour gériatriques, COLMAR, FRANCE, 07-/06/2018 - 08/06/2018; Les gériatres et neurologues sont régulièrement confrontés à la question du maintien ou de l'arrêt de la conduite automobile chez des patients présentant un Trouble Neuro- Cognitif (TNC). Des stratégies de compensation, apprises au cours d'ateliers de prévention, peuvent être utilisées pour réduire le risque d'accident en cas de TNC et maintenir transitoirement la conduite automobile avant son arrêt définitif. Le projet ACCOMPAGNE est un programme de prévention de sécurité routière. Il est composé de différents ateliers : atelier de présentation, atelier cognitif, atelier représentation psychologiques, atelier législation, atelier foire aux questions, atelier solutions. Ce programme est destiné aux patients et aux aidants.

Drivers suffering from one or more medical conditions may also have impaired visual, cognitive and/or motor functions that interfere with their ability to drive. Faced with an ageing population and the high prevalence of medical conditions, it is important for us to identify drivers who are at risk of having accidents, while at the same time looking for solutions that will help maintain their mobility and keep them independent for as long as possible.The question of the driving ability of individuals suffering from one or more medical conditions is at the heart of the concerns of doctors, the individuals themselves and their families, as well as driving licence policies and the licence-issuing authorities. From a legislative point of view, the European Union and the authorities that issue driving licences have imposed certain conditions on the renewal of driving licences and even obtaining them in the first place for people who have specific medical conditions. But despite everything, the procedures used to evaluate a person's ability to drive vary from country to country. In Belgium, to be able to drive a motor vehicle, the driver needs not only to be in possession of a driving licence, but also be capable of driving safely. This means that he or she must be physically and mentally able to drive in traffic in complete safety. Belgian regulations on driving ability will be detailed in this report. Evidence from the literature notes that the number of fatal road accidents is higher for individuals suffering from problems associated with alcohol or sleeping disorders.Drivers may be considered as being at risk of having accidents based on detailed accident data and/or the opinions issued as to their ability to drive provided by doctors or assessors on the road. Individual drivers' performances on a driving simulator or out on the road are sometimes taken into account to identify any difficulties they may have when driving and also to determine whether they are likely to be at risk of having an accident. In Belgium, assessments of driving ability are carried out by doctors and/or by the CARA, the body accredited for assessing the driving ability of individuals with reduced functional capabilities. The key figures relative to driving ability in Belgium will be the subject of section 4 of this report.A literature review shows that the risk of accidents varies according to the group of medical disorders. The problems associated with substance abuse (such as alcohol and drugs), psychiatric problems, sleep disorders (such as sleep apnoea) and neurological conditions (such as dementia) have been identified as the medical conditions most likely to have an adverse effect on driving behaviour.Measures in terms road safety policies may be envisaged in order to mitigate the functional problems associated with the presence of one or more medical conditions in a person. The individuals in question may also make changes to their driving habits and behaviour based on their particular difficulties. Vehicle technology, as well as the arrival of self-driving cars may also be of value in ensuring safer driving. However, the level of acceptance and the effectiveness of these new technologies still remain to be determined. Modifications in terms of infrastructure may also improve the way they drive.; Les conducteurs souffrant d'une ou plusieurs affections médicales peuvent avoir des déclins au niveau des fonctions visuelles, cognitives et/ou motrices qui interfèrent avec l'aptitude à la conduite automobile. Face au vieillissement démographique de la population et à la forte prévalence d'affections médicales, il est important d'identifier les conducteurs à risque d'accidents et de rechercher des solutions pour maintenir leur mobilité et leur indépendance le plus longtemps possible.La question de l'aptitude à la conduite des personnes souffrant d'une ou plusieurs affections médicales est au coeur des préoccupations des médecins, des familles, des personnes elles-mêmes, des politiques et des autorités du permis de conduire. Sur le plan législatif, l'Union Européenne et les autorités délivrant le permis de conduire ont imposé certaines conditions au renouvellement ou à l'obtention du permis de conduire pour les personnes présentant des affections médicales particulières. Malgré tout, les procédures d'évaluation de l'aptitude à la conduite varient suivant les pays.La littérature fait état d'un nombre d'accidents mortels plus important pour les personnes qui souffrent de problèmes liés à l'alcool ou de troubles du sommeil.Les personnes peuvent être considérées à risque d'accidents sur base des données détaillées d'accidents et/ou des avis d'aptitude à la conduite émis par les médecins ou les évaluateurs sur route. Les performances sur simulateur de conduite ou sur route réelle sont parfois prises en compte pour identifier les difficultés lors de la conduite et pour déterminer les conducteurs à risque d'accidents.Les résultats de la littérature montrent que le risque d'accidents varie selon le groupe d'affections médicales. Les problèmes liés à l'abus de substances (telles que l'alcool et les drogues), les troubles psychiatriques, les troubles du sommeil (par exemple l'apnée du sommeil), les affections neurologiques (par ex. la démence) ont été identifiés comme les affections médicales les plus susceptibles d'influencer le comportement de conduite.De manière à pallier aux problèmes fonctionnels liés à la présence d'une ou plusieurs affections médicales, des mesures en termes de politiques de sécurité routière peuvent être envisagées. La personne peut également adapter son comportement de conduite en fonction de ses difficultés. Les technologies à l'intérieur du véhicule et l'arrivée des véhicules autonomes peuvent également aider à maintenir la conduite sécuritaire. Cependant, l'acceptabilité et l'efficacité de ces technologies restent encore à déterminer. Des modifications au niveau de l'infrastructure pourraient également améliorer leur comportement en conduite.

Languages, Linguistics and Technology: New Trends in Language Teaching, Interpreting and Translation, FORLI, ITALIE, 10-/11/2017 - 11/11/2017; Eye movements and pupil dilation are neurophysiological measures of cognitive workload. Cognitive workload is defined as the amount of mental effort needed to execute a task. This study focuses on the neurophysiology of second language acquisition to better understand how students learn a second language. If we can demonstrate that cognitive workload is directly related to the level of experience with Spanish as a second language, future studies will be designed that will use cognitive workload as a means of student learning and teaching strategies. Novice and experienced Spanish speakers enrolled in our classes were asked to complete a translation task that is similar in nature to activities they are normally given in an educational setting. The specific aims were: 1. To compare eye movements and pupil dilation in novice and experienced Spanish speakers while performing a translation task. 2. To investigate the effect of a semester course of Spanish on visual scanning and pupil dilation. In the first case, we verified that visual scanning patterns and pupil dilation in experienced Spanish speakers were more efficient than in novice Spanish speakers. However, in the second case, we discovered that the students showed more pupil dilation in translation tasks after a full semester of Spanish studies. Based on the data, this study will explain the possible reasons for these results and contribute to the ongoing investigation of the neurophysiological mechanisms of second language skill acquisition.

Research Objectives: To investigate the effect of cognitive demand on functional visual field performance in drivers with glaucoma. Design: It was a proof of concept study and had a cross-sectional study design.Setting: Patient population from the Department of Ophthalmology at Augusta University, GA. Healthy controls through word-of-mouth and flyer advertisement.Participants: 20 drivers with open-angle glaucoma and 13 age- and sex-matched controls without glaucoma were recruited through word-of-mouth and flyer advertisement.Interventions: No intervention was involved in the study.Main Outcome Measure(s): Visual field performance was evaluated in a static visual field condition (C1), dynamic visual field condition (C2), and dynamic visual field condition with a psychomotor activity (C3) using an interactive, desktop driving simulator. Correct responses (accuracy) and cognitive workload, recorded in real-time through pupillometry were comapred between groups and between conditions.Results: Adding cognitive demand (C2 and C3) to the static visual field test (C1) adversely affected accuracy and response times, in both groups (p < 0.05). However, drivers with glaucoma performed disproportionally worse than did control drivers when the static condition changed to a dynamic condition {C2 vs C1 accuracy; (patients: median difference, (Q1-Q3) 3, 2-6.50 vs controls: 2, 0.50-2.50, p = 0.05} and to a dynamic condition with psychomotor activity (C3 vs C1 accuracy; patients: 2, 2-6 vs controls: 1, 0.50-2, p = 0.02). Overall, drivers with glaucoma exhibited greater cognitive workload than controls (p = 0.02). Conclusion/Discussion: Cognitive demand disproportionally affects visual field performance in drivers with glaucoma. Our results will inform the development of a performance-based visual field test for drivers with glaucoma.

Concussion in Sport 5th International Consensus Conference, BERLIN, ALLEMAGNE, 27-/10/2016 - 28/10/2016; Objective: To compare simulated driving performance between concussed and control participants. Design: Cross-sectional. Setting: Laboratory. Participants: Fourteen concussed participants and 14 non-concussed age and driving experience matched controls with no neurological disorders, medications causing drowsiness, or heavy drugs/alcohol use (Age:20.3years, 95%CI:19.9,20.7). Interventions (or Assessment of Risk Factors): Participants completed a 7.6 minute, 20.5km driving simulation task containing curves, crosswalks, accidents, rural/urban areas, pedestrians, overtaking, and evasion. Concussed participants completed driving simulation within 48 hours of becoming asymptomatic (15.9 days post-concussion, 95%CI:10.7,21.0) and were deemed clinically recovered by a medical professional using a multifaceted concussion evaluation. Outcome measures: We compared total number of accidents, tickets, and lane excursions between groups. We also compared average velocity (km/hr), standard deviation of velocity, lateral lane position (m), and lateral lane position standard deviation throughout simulation subsections. One-way ANOVAs were used (±=0.05). Main Results: Concussed participants committed more frequent lane excursions compared to controls (concussed: 10.9, 95%CI:8.3,13.5; controls: 7.4, 95%CI:6.0,8.8; p=0.02). Concussed participants exhibited greater lateral lane position standard deviation compared to controls during the first (concussed: 1.1m, 95%CI: 0.8,1.5; controls:0.7m, 95%CI:0.6, 0.9; p=0.02) and final curve (concussed: 1.2m, 95%CI:1.1,1.3; controls: 1.0m, 95%CI:0.9,1.1; p=0.04). Conclusions: Despite being considered clinically recovered, concussed participants were less able to center the vehicle in the lane and entered the shoulder more frequently, especially when navigating curves. A concussion may impair visual, motor, and/or cognitive skills necessary to safely drive. Further research is needed to determine when it is safe to return to driving following concussion.

The most frequent motorcycle accidents involve another vehicle violating the motorcycle's right-of-way at an intersection. In-depth accident studies have shown that perceptual errors made by other vehicle drivers are a very frequent cause of motorcyclists' accidents and fatalities. Two kinds of perceptual errors can be distinguished. The first one is no or late detection of the motorcycle, which is mainly due to its low visual conspicuity (especially because of their small size). The principal safety measure in the past has been the use of daytime running lights (DRLs) by motorcycles, which became compulsory in the seventies in many countries. This conspicuity advantage of motorcycles as the only vehicles with DRLs is presently getting lost by the growing use of DRLs by cars as well. In an earlier study we have shown that car DRLs are actually competing light patterns that create visual noise and decrease the detectability of motorcycles. The second kind of perceptual error, less well known, is the misperception of the approaching motorcycle's speed (which is underestimated) and time-to-arrival (which is overestimated) that also contributes to accident occurrence. In order to reduce motorcycle accidents, and especially to improve motorcycle perceptibility (both detection and speed perception) by other vehicle drivers, ITS based on vehicle-to-vehicle communication will probably provide effective long-term solutions (>15 years). But until then, other solutions have to be found and could quite easily be implemented, by considering innovative headlight configurations for motorcycles. In two simulator studies, we tested various motorcycle headlight configurations, intended for remedying simultaneously the two perceptual errors made by other vehicle drivers. The impact of different headlight configurations (using colour coding and additional lights) was studied in the presence of visual distractors (car front lights: only DRLs, only dipped beams, DRLs and dipped beams) and in different illumination conditions (nighttime, dusk and daytime conditions). The results of the first study on motorcycle motion perception indicated that headlight configurations that accentuate the vertical dimension of the motorcycle (additional lights on the fork and on the rider's helmet) led automobilists to adopt larger safety margins towards motorcycles. The advantage provided by the innovative headlight configuration showed up especially at low illumination conditions (night and dusk) where the motorcycle outline was not visible or difficult to perceive. On the contrary, a triangular design (with two additional lights on the handlebars) showed no significant improvement. The findings of the second study on motorcycle detection showed that additional yellow lights (on the motorcyclist's helmet and the motorcycle fork) significantly improved motorcycle conspicuity and produced the best motorcycle detection performance, even in the presence of a great number of competing car headlights (when LEDs and dipped beams were lit at the same time). The findings also show that motorcycle detection was hampered when cars simultaneously lit their DRLs and dipped beams. The great number of competing light sources thus constitues visual noise detrimental to motocycle detectability. When combining the results of our studies, we suggest a motorcycle headlight configuration that consists in one white central headlamp, an additional yellow light on the helmet and two additional yellow lights on the fork. This ergonomic solution has the potential of successfully counteracting the two kinds of perceptual errors made by other vehicles drivers., La communication a porté sur le projet Avimoto qui s'est intéressé à la perceptibilité des motocyclistes. Deux expériences ont été présentées, abordant les deux principales erreurs perceptives (erreur de détection et mauvaise perception du mouvement du motocycle) faites par les autres conducteurs lors de leur interaction avec des motocyclistes. Plusieurs configurations de feux avant de moto ont été testées sur simulateur, débouchant sur la recommandation d'une configuration consistant en un feux central blanc et 3 feux additionnels jaunes sur le casque du motard et la fourche de la moto. Cette configuration a montré être capable de remédier simultanément aux deux types d'erreurs perceptives mentionnées plus haut.