Post-stroke fatigue: a problem of altered corticomotor control?

Area of Science:

• Neuroscience
• Rehabilitation Medicine
• Motor Control

Background:

• Diminished motor cortex excitability is linked to increased post-stroke fatigue.
• Motor cortex excitability influences movement parameters like reaction and movement times.

Purpose of the Study:

• To investigate the impact of post-stroke fatigue on movement and reaction times.
• To determine if post-stroke fatigue influences movement speed or preparation.

Main Methods:

• 41 first-time stroke survivors were categorized into high (n=21) and low (n=20) fatigue groups based on Fatigue Severity Scale scores.
• Movement times, simple reaction times, and choice reaction times were assessed in both affected and unaffected hands.

Main Results:

• Affected hand movement times were significantly slower in the high-fatigue group compared to the low-fatigue group.
• No significant differences in reaction times were observed between the high and low fatigue groups for either hand.

Conclusions:

• Post-stroke fatigue is associated with impaired movement speed, likely stemming from reduced motor cortex excitability.
• The effects of fatigue appear localized to the lesioned hemisphere, suggesting it affects movement execution rather than preparation.
• Targeting low motor cortex excitability in the lesioned hemisphere may be a promising therapeutic strategy for post-stroke fatigue.