Task-relevant cognitive and motor functions are prioritized during prolonged speed-accuracy motor task performance.

Area of Science:

• Neuroscience
• Motor Control
• Cognitive Psychology

Background:

• Prolonged motor tasks can impact psychological, cognitive, and motor functions.
• Understanding how the brain adapts to sustained effort is crucial for performance optimization.

Purpose of the Study:

• To investigate the effects of a 2-hour speed-accuracy motor task on various functional indicators.
• To determine how task-relevant versus task-irrelevant functions are affected by prolonged, fatiguing motor activity.

Main Methods:

• Ten young men performed a 2-hour fast- and accurate-reaching movement task and a control task.
• Evaluated psychological (motivation, effort, fatigue), cognitive (working memory), psychomotor (visuomotor tracking), and motor (motor-evoked potentials, grip strength) functions.
• Utilized prefrontal cortex oxygenation measurements during conflict detection.

Main Results:

• Despite increased fatigue and perceived effort, motor task performance improved over 2 hours.
• Working memory function and prefrontal cortex oxygenation increased post-task.
• Efficiency of response inhibition and visuomotor tracking decreased post-task.
• Motor-evoked potential amplitude increased, while grip strength remained unchanged.

Conclusions:

• Sustained performance on a 2-hour speed-accuracy task involves maintaining or improving task-relevant functions.
• Less critical functions are impaired to support the primary motor task under fatigue.
• This highlights a selective neural adaptation to prolonged, demanding motor activity.