Prescheduled Interleaving of Processing Reduces Interference in Motor-Cognitive Dual Tasks

Area of Science:

• Cognitive Neuroscience
• Motor Control
• Human Factors

Background:

• Interleaving cognitive and motor tasks can be efficient if resource allocation is dynamic.
• Temporal regularity of events may influence the success of task interleaving.

Purpose of the Study:

• To investigate how stimulus timing regularity affects cognitive task performance during walking.
• To examine the interaction between motor task regularity and cognitive load.

Main Methods:

• Fifteen subjects performed a 2-back task while walking at varying speeds.
• Stimulus onsets were systematically varied relative to the step cycle (regular vs. irregular).
• Measures included reaction time, accuracy, and motor performance metrics.

Main Results:

• No task interference was observed when stimuli were temporally regular within the step cycle.
• Reaction times were prolonged when stimuli appeared earlier than expected.
• Reaction times were fastest when stimuli appeared later than expected.

Conclusions:

• Cognitive processing during walking is not impaired by regular, predictable stimuli.
• Unexpectedly timed stimuli reveal a pre-scheduled resource allocation strategy linked to the motor task's cycle.
• This suggests the motor task influences cognitive processing demands predictively.