Neural Correlates of Dual-Task Walking: Effects of Cognitive versus Motor Interference in Young Adults

Abstract

Walking while concurrently performing cognitive and/or motor interference tasks is the norm rather than the exception during everyday life and there is evidence from behavioral studies that it negatively affects human locomotion. However, there is hardly any information available regarding the underlying neural correlates of single- and dual-task walking. We had 12 young adults (23.8 ± 2.8 years) walk while concurrently performing a cognitive interference (CI) or a motor interference (MI) task. Simultaneously, neural activation in frontal, central, and parietal brain areas was registered using a mobile EEG system. Results showed that the MI task but not the CI task affected walking performance in terms of significantly decreased gait velocity and stride length and significantly increased stride time and tempo-spatial variability. Average activity in alpha and beta frequencies was significantly modulated during both CI and MI walking conditions in frontal and central brain regions, indicating an increased cognitive load during dual-task walking. Our results suggest that impaired motor performance during dual-task walking is mirrored in neural activation patterns of the brain. This finding is in line with established cognitive theories arguing that dual-task situations overstrain cognitive capabilities resulting in motor performance decrements.

Figure 1

Subjects' mean gait performance and the respective variability measures, separated by condition (ST walk: single-task walking, DT-CI: walking + cognitive interference, DT-MI: walking + motor interference) for (a) gait velocity, (b) stride length, (c) stride time, (d) CV-gait velocity, (e) CV-stride length, and (f) CV-stride time. Circles represent mean values and error bars the respective 95% confidence interval.

Figure 2

Subjects' mean average voltage across the cranial midline, separated by condition (ST walk: single-task walking, DT-CI: walking + cognitive interference, DT-MI: walking + motor interference). Values represent average voltage for (a) FP_z, (b) F_z, (c) FC_z, (d) C_z, (e) P_z, and (f) PO_z. Cyan circles represent mean alpha frequency; black circles show mean beta frequency; error bars represent the respective 95% confidence interval.