[Effects of motor activity on cognitive performance of patients with traumatic brain injury during dual tasking]

The use of dual task paradigms has revealed behavioural interactions between certain motor tasks, like standing or walking, and cognitive tasks when performed simultaneously. Despite the potential relevance of these findings accounting for certain neurological symptoms (i.e., falls), or for the design of new therapeutic interventions, there is few information available about such interaction effects in traumatic brain injury (TBI).

To assess the presence of cognitive-motor interactions during dual tasking in TBI patients.

Twenty TBI patients and 19 healthy matched controls performed two attentional and two working memory tasks (simple reaction times, complex reaction times, 1-back numeric, 1-back spatial) during dual task conditions, that is, at the same time than one motor task (standing and walking), and during single task conditions (without a motor task). Reaction times were recorded in response to all cognitive tasks.

Patients exhibit slower performance than controls in all cognitive tasks (p < 0.05). While neither patients nor controls showed changes in reaction times in the two simpler attentional tasks during dual tasking as compared to single tasking conditions, TBI patients do exhibit improvements in working memory tasks (F(2, 74) = 2.9; p < 0.05) during dual tasking-walking (p < 0.02).

The possible causes of positive cognitive-motor interactions during simultaneous execution of motor-working memory tasks in TBI patients are discussed, as well as the potential therapeutic value of dual task paradigms in the rehabilitation of these patients.