Thérèse Audet

Visual neglect and left-sided context effects

Patients with visual neglect generally fail to respond to an item placed on the left of a target location, even when both stimuli are situated in the right visual field. Little is known, however, about the level of processing for the unattended items. Two patients with left visual neglect served as subjects in several experiments measuring passive contextual effects of a left-sided item on responses to a focal target. The results reveal that a neglected item may influence the speed of responding. The findings are interpreted relative to the loci of context effects in normal subjects.

Errorless-Based Techniques Can Improve Route Finding in Early Alzheimer's Disease: A Case Study

Topographical disorientation is a common and early manifestation of dementia of Alzheimer type, which threatens independence in activities of daily living. Errorless-based techniques appear to be effective in helping patients with amnesia to learn routes, but little is known about their effectiveness in early dementia of Alzheimer type. A 77-year-old woman with dementia of Alzheimer type had difficulty in finding her way around her seniors residence, which reduced her social activities. This study used an ABA design (A is the baseline and B is the intervention) with multiple baselines across routes for going to the rosary (target), laundry, and game rooms (controls). The errorless-based technique intervention was applied to 2 of the 3 routes. Analyses showed significant improvement only for the routes learned with errorless-based techniques. Following the study, the participant increased her topographical knowledge of her surroundings. Route learning interventions based on errorless-based techniques appear to be a promising approach for improving the independence in early dementia of Alzheimer type.

Code-Dependent Pathways for Number Transcoding: Evidence from a case of Selective Impairment in Written Verbal Numeral to Arabic Transcoding

This article presents a brain-damaged patient (RR) suffering from cognitive deficits following neurological insults, who showed a selective impairment in number transcoding. Except for written verbal numeral to arabic transcoding, his ability to transcode numerals, including writing arabic numerals to dictation, is largely preserved. Other number processing skills, including numeral recognition, numeral comprehension, and calculation, were unimpaired. Semantic and asemantic models of number processing cannot easily account for the patients performance and it is suggested that the number transcoding system should include different code-dependent pathways for arabic transcoding from spoken verbal numerals and from written verbal numerals. Since the errors produced in the impaired transcoding rely upon the syntactical structure of numeral stimuli, it is also proposed that transcoding code-dependent pathways should reflect the structure of the verbal numeral system, especially the difference between sum and product relationships.

Awareness Tool for Safe and Responsible Driving (OSCAR): A Potential Educational Intervention for Increasing Interest, Openness and Knowledge About the Abilities Required and Compensatory Strategies Among Older Drivers

Objective: This pilot study aimed to verify the impact of the awareness tool for safe and responsible driving (OSCAR) on older adults’ (1) interest, openness, and knowledge about the abilities and compensatory strategies required for safe driving; (2) awareness of changes that have occurred in their own driving abilities; and (3) actual utilization of compensatory strategies. Methods: A preexperimental design, including a pretest (T0) and posttest (T1) 8 to 10 weeks after exposure to the intervention, was used with 48 drivers aged between 67 and 84. The participants had a valid driving license and drove at least once a week. Results: Overall, the results demonstrate that OSCAR increased interest, openness, and knowledge about the abilities and compensatory strategies of older drivers (P <.01). After exposure to OSCAR, the majority of the participants confirmed that changes had occurred in at least one of their abilities. Moreover, half of the older drivers reported having started using 6 or more compensatory strategies. Conclusion: In summary, in addition to increasing older adults’ interest, openness, and knowledge to discussion about driving, OSCAR also improved awareness of the changes that could negatively impact safe driving and enhanced utilization of compensatory strategies. While promoting safe driving and the prevention of crashes and injuries, this intervention could ultimately help older adults maintain or increase their transportation mobility. More studies are needed to further evaluate OSCAR and identify ways to improve its effectiveness.

Re-Evaluating the Effect of Unilateral Brain Damage on Simple Reaction Time to Auditory Stimulation

Results of a previous experiments designed to test if there is a right hemisphere superiority over the left hemisphere in the capacity to react quickly to a stimulus have not lead to an unambiguous conclusion, although the majority of studies indicate that right-brain-damaged patients are generally slower than left-brain-damaged patients. The present experiment re-examines the speed of reaction time to auditory stimulation in a population of brain-damaged patients. Each case was presented with 120 auditory events and variable inter-trial intervals (from 1 s to 15 s). To ensure homogeneity of the population tested, only patients with a cerebro-vascular accident were chosen. The results show that the right-brain-damaged patients were not generally slower than left-brain-damaged patients. However, a marked deterioration in performance over time was observed in the right-hemisphere group while a small amount of improvement was found in the normal and left-brain-damaged patients. The outcome is discussed in terms of a sustained attention deficit associated with right-hemisphere damage.

From “Cinquante-Six” to “5quante-Six”: The origin of intrusion errors in a patient with probable alzheimer disease

This paper presents a detailed single-case study of a patient (BT) with dementia of the Alzheimers type who showed impairments in number processing. Numeral comprehension and calculation abilities were largely preserved but the patient encountered substantial difficulties in transcoding tasks. In addition to syntactic errors, she produced numerous perseverations and intrusion errors, especially when she had to transcode arabic numerals into written verbal numerals and vice versa. In the present study, we show that these errors are concomitant with but not dependent on the syntactic deficit. We also demonstrate that their production is not exclusive to the numerical domain but clearly depend on the attentional processing load as well as on the familiarity of the transcoding task. To account for these data, we suggest that perseverations and intrusion errors are attentional in nature and originate from a unique impairment in selective attention capacities.

Mobility profile and wheelchair driving skills of powered wheelchair users: Sensor-based event recognition using a support vector machine classifier

This paper presents a method to automatically recognize events and driving activities during the use of a powered wheelchair (PW). The method uses a support vector machine classifier, trained from sensor-based data from a datalogging platform installed on the PW. Data from a 3D accelerometer positioned on the back of the PW were collected in a laboratory space during PW driving tasks. 16-segmented events and driving activities (i.e. impacts from different side on different objects, rolling down or up on incline surface, going across threshold of different height) were performed repeatedly (n=25 trials) by one operator at three different speeds (slow, normal, high). We present results from an experiment aiming to classify five different events and driving activities from the sensor data acquired using the datalogging platform. Classification results show the ability of the proposed method to reliably segment 100% of events, and to identify the correct event type in 80% of events.

Development and Validation of an Awareness Toolfor Safe and Responsible Driving (OSCAR)

Research Centre on Aging, Health and Social Services Centre-University Institute of Geriatrics of Sherbrooke (CSSS-IUGS), 1036 Belvedere South, Sherbrooke (Quebec), J1H 4C4, Canada. Faculty of Medicine and Health Sciences, University of Sherbrooke, 3001 12 Avenue North, Sherbrooke (Quebec), J1H 5N4, Canada. Faculty of Humanities, University of Sherbrooke, 2500 University Boulevard, Sherbrooke (Quebec), J1K 2R1, Canada. Centre for Interdisciplinary Research in Rehabilitation of Greater Montreal, 2275, Laurier East Street, Room 214, Montreal (Quebec), H2H 2N8, Canada. School of Physical and Occupational Therapy, McGill University, 3654 Promenade Sir William Osler, Montreal (Quebec), H3G 1Y5, Canada. Center for Research on Safe Driving, Lakehead University (Room BB 1043), 955 Oliver Road, Thunder Bay (Ontario), P7B 5E1, Canada. Eastern Townships Rehabilitation Center, 300 King East Street, Room 200, Sherbrooke (Quebec), J1G 1B1, Canada. School of Optometry, University of Montreal, 3744 Jean-Brillant, Room 110, Montreal (Quebec), H3T 1P1, Canada.

Outil de sensibilisation des conducteurs âgés aux capacités requises pour une conduite automobile sécuritaire et responsable (OSCAR) : développement et validation

L’objectif de cette etude etait de developper et de valider un outil d’intervention pour sensibiliser les conducteurs âges aux capacites requises et aux strategies compensatoires pour une conduite automobile securitaire. Une recension elargie des ecrits a d’abord ete realisee pour developper l’Outil de Sensibilisation des conducteurs âges aux capacites requises et aux strategies compensatoires pour une conduite automobile securitaire et responsable (OSCAR). L’outil comprend une serie de 15 questions et 15 capsules educatives en lien avec le vieillissement et la conduite automobile. Un dispositif experimental incluant un pre-test et un post-test huit a dix semaines apres l’intervention a ensuite ete utilise aupres de 48 personnes âgees entre 67 et 84 ans qui conduisaient au moins une fois par semaine. A la suite de la passation de l’OSCAR, les resultats demontrent que l’interet, l’ouverture et les connaissances des aines sur les capacites requises et les strategies compensatoires ont augmente de facon significative (p