Motor imagery in chronic neglect: An fMRI pilot study

Area of Science:

• Neuroscience
• Rehabilitation Medicine
• Cognitive Psychology

Background:

• Motor imagery training shows promise for stroke rehabilitation.
• Visuospatial neglect is a common and persistent deficit after right-hemispheric stroke.
• Understanding brain mechanisms of motor imagery in neglect is crucial for treatment efficacy.

Purpose of the Study:

• To investigate the neural basis of motor imagery in chronic stroke patients with visuospatial neglect.
• To determine if patients with neglect can perform motor imagery of hand movements.
• To explore the relationship between neglect severity and brain activation during motor imagery.

Main Methods:

• Pilot study involving nine chronic neglect patients post-right-hemispheric stroke.
• Functional magnetic resonance imaging (fMRI) was used to measure brain activity.
• Participants performed motor imagery of a finger opposition task with both unaffected and affected hands.

Main Results:

• Imagery of unaffected hand movements activated left sensorimotor areas.
• Imagery of the affected hand showed activation in left premotor cortex, supplementary motor area, and dorsolateral prefrontal cortex.
• Activation in the supplementary motor area during affected hand imagery correlated negatively with time since stroke onset and visual imagery capacity, and was related to neglect severity.

Conclusions:

• Patients with chronic neglect demonstrate motor imagery capacity.
• Compensatory neural processing in ipsilateral brain regions, particularly the supplementary motor area, is observed during motor imagery of the affected hand.
• Neglect severity, specifically related to supplementary motor area activation, suggests potential for motor imagery training in these patients, despite limitations of this pilot study.