Attentional management of cognitive-motor interference in adults during walking: Insights from an EEG study

Dual-task paradigms, which involve performing cognitive and motor tasks simultaneously, are commonly used to study how attentional resources are allocated and managed under varying task demands. This study aimed to investigate cognitive-motor interferences (CMI) under different levels of cognitive and motor task difficulty without instruction on task prioritization. 17 healthy young adults performed an auditory oddball task with increasing cognitive and motor (walking vs. sitting) difficulty. Cognitive and motor performances, along with P3 (P3a and P3b) brainwave components, were analysed. Increasing cognitive difficulty resulted in more errors and increased P3a amplitude, reflecting enhanced attentional demand, while P3b remained unaffected. This suggests a threshold effect on attentional resources. Motor complexity lengthened P3a and P3b latencies without affecting amplitude, indicating delayed attentional resource recruitment. Additionally, walking with the most difficult cognitive task increased cognitive error, suggesting attentional resource limits. With increased motor and cognitive complexity, CMI emerged, leading to cognitive error increase and improved gait stability without amplitude changes in P3a and P3b. Two hypotheses were proposed: motor prioritization and motor facilitation. Our study suggests managing attentional resources to balance cognitive and motor tasks rather than linearly increasing task complexity. Viewing dual tasks as a new, integrated task is proposed, supported by previous neural network integration studies. Thus, understanding how the brain organizes tasks in response to constraints is crucial for comprehending complex task execution.