Increased cognitive load during simple and complex motor tasks in acute stage after stroke

Area of Science:

• Neuroscience
• Rehabilitation Medicine
• Medical Imaging

Background:

• Stroke frequently causes motor impairments, affecting the primary motor cortex, prefrontal cortex, and parietal cortex.
• Understanding cortical activation patterns is crucial for stroke recovery and rehabilitation strategies.

Purpose of the Study:

• To investigate brain activation in primary motor cortex, prefrontal cortex, and parietal cortex during motor tasks.
• To compare activation between hemiparetic and non-hemiparetic hands in stroke survivors.
• To track changes in cortical activation over the early weeks and months post-stroke.

Main Methods:

• Functional magnetic resonance imaging (fMRI) was used to assess brain activity.
• Seven patients with left-hemisphere stroke participated.
• fMRI scans were conducted at 1 week, 3 weeks, and 3 months post-stroke.

Main Results:

• Both simple and complex motor tasks activated motor, prefrontal, and parietal cortices in most fMRI sessions.
• By 3 months post-stroke, reduced activation was observed in the primary motor cortex and parietal cortex (contralesional hemisphere) during simple tasks with the hemiparetic hand.
• This reduction in activation was less pronounced during complex tasks.

Conclusions:

• Bilateral activation of prefrontal and parietal cortices may play a role in stroke recovery for mildly impaired patients.
• The findings suggest potential for measuring cortical rehabilitation effectiveness using fMRI.