The effects of instructions on dual-task walking and cognitive task performance in people with Parkinson's disease

Abstract

Gait impairments are prevalent among people with Parkinson's disease (PD). Instructions to focus on walking can improve walking in PD, but the use of such a cognitive strategy may be limited under dual-task walking conditions, when walking is performed simultaneously with concurrent cognitive or motor tasks. This study examined how dual-task performance of walking and a concurrent cognitive task was affected by instructions in people with PD compared to healthy young and older individuals. Dual-task walking and cognitive task performance was characterized under two sets of instructions as follows: (1) focus on walking and (2) focus on the cognitive task. People with PD and healthy adults walked faster when instructed to focus on walking. However, when focused on walking, people with PD and young adults demonstrated declines in the cognitive task. This suggests that dual-task performance is flexible and can be modified by instructions in people with PD, but walking improvements may come at a cost to cognitive task performance. The ability to modify dual-task performance in response to instructions or other task and environmental factors is critical to mobility in daily life. Future research should continue to examine factors that influence dual-task performance among people with PD.

Figure 1

Gait speed (a), response latency (b), and response accuracy (c) for all groups in the single-task (ST; for reference) and both dual-task conditions. Red squares show data for healthy young adults. Orange triangles show data for healthy older adults. Purple circles show data for people with PD. Symbols represent means and bars show standard errors.

Figure 2

The effects of instructions on walking DTEs (a) and composite cognitive task DTEs (b) for the healthy young adults (red bars), healthy older adults (orange bars), and people with PD (purple bars).