Effect of type of cognitive task and walking speed on cognitive-motor interference during dual-task walking

- Effect of explicitly different cognitive tasks on dual-task walking was assessed.
- Prioritization of cognitive task is altered with the type of cognitive task.
- Walking speed has an impact on cognitive task performance while dual-task walking.
- Slow walking decreases cognitive cost of dual-task walking.

ObjectiveWe aimed to determine the effect of distinctly different cognitive tasks and walking speed on cognitive-motor interference of dual-task walking.MethodsFifteen healthy adults performed four cognitive tasks: visuomotor reaction time (VMRT) task, word list generation (WLG) task, serial subtraction (SS) task, and the Stroop (STR) task while sitting and during walking at preferred-speed (dual-task normal walking) and slow-speed (dual-task slow-speed walking). Gait speed was recorded to determine effect on walking. Motor and cognitive costs were measured.ResultsDual-task walking had a significant effect on motor and cognitive parameters. At preferred-speed, the motor cost was lowest for the VMRT task and highest for the STR task. In contrast, the cognitive cost was highest for the VMRT task and lowest for the STR task. Dual-task slow walking resulted in increased motor cost and decreased cognitive cost only for the STR task.ConclusionsResults show that the motor and cognitive cost of dual-task walking depends heavily on the type and perceived complexity of the cognitive task being performed. Cognitive cost for the STR task was low irrespective of walking speed, suggesting that at preferred-speed individuals prioritize complex cognitive tasks requiring higher attentional and processing resources over walking. While performing VMRT task, individuals preferred to prioritize more complex walking task over VMRT task resulting in lesser motor cost and increased cognitive cost for VMRT task. Furthermore, slow walking can assist in diverting greater attention towards complex cognitive tasks, improving its performance while walking.