Biomechanical and cognitive interactions during Visuo Motor Targeting Task

Background: Biomechanical analyses primarily focus on physical aspects of human movement; however, it is not understood how walking is affected while simultaneously performing a demanding cognitive task - a form of Cognitive-Motor Interference (CMI). CMI occurs when performance of a primary task (e.g. walking) is affected following the introduction of a cognitive task (e.g. visual search). Research question: Would Visuo Motor Targeting Task (VMTT) impair visual search performance and reduce the margin of stability (MoS) at higher gait speeds? Methods: A protocol was developed to investigate responses of the neuromuscular system while performing a complex visual search task. The Computer Assisted Rehabilitation ENvironment (CAREN, Motekforce Link, Netherlands) system was used for the experimental design. Twenty male participants (Age = 24.2 ? 2.5yrs, Weight = 70.3 ? 10.6 kg, Height = 178.0 ? 9.1 cm) located and pointed towards targets in complex scenes while walking at different gait speeds (0.55, 1.11 and 1.67 m/s.) or while stationary. The cost of visual search during a Visuo Motor Targeting Task (VMTT) was based on the pointing accuracy during the visual search task. Results: A two-way repeated measure ANOVA showed that MoS in the ML direction significantly improved with increased gait speed and during the visual search task. There was also a significant interaction with MoS improvement being greater during the visual search task at high gait speeds. MoS in the AP was only affected by gait speed. Visual performance and cost of visual search were enhanced during walking versus standing up to 25 %. Significance: This study investigated CMI at different gait speeds, which may have implications in postural control, falls and other neurological disorders.

Automated summary

This study investigated the effects of Cognitive-Motor Interference at different gait speeds, with results showing that performing a cognitive task during high-speed walking significantly improves stability margins. The increase in gait speed resulted in significant improvements in MoS during the visual search task, and performing visual search while walking can enhance visual performance and reduce costs.