Relationship Between Ipsilesional Upper Extremity Motor Function and Corpus Callosum Integrity in Patients With...

Area of Science:

• Neuroscience
• Neurology
• Rehabilitation Medicine

Background:

• Stroke often causes upper extremity (UE) motor deficits.
• The corpus callosum facilitates interhemispheric communication, crucial for motor control.
• Understanding the relationship between callosal integrity and UE function is vital for stroke rehabilitation.

Purpose of the Study:

• To investigate the link between ipsilesional upper extremity (UE) motor function and corpus callosum integrity in stroke survivors.
• To explore how lesions in dominant vs. non-dominant hemispheres affect this relationship.

Main Methods:

• Assessed UE function using Jebsen-Taylor Hand Function Test (JHFT), 9-hole peg test (9HPT), and strength tests.
• Calculated fractional anisotropy (FA) to measure the integrity of 5 corpus callosum subregions.
• Used Pearson's correlation to analyze the relationship between UE function and callosal integrity.

Main Results:

• Significant correlation found between JHFT/9HPT performance and frontal lobe-projecting corpus callosum integrity in the left (non-dominant) lesion group.
• No significant correlation observed between UE motor function and the splenium subregion in the right (dominant) lesion group.
• Motor deficits in the non-dominant ipsilesional UE correlated with callosal fiber integrity to the prefrontal area.

Conclusions:

• Callosal integrity, particularly projections to the prefrontal cortex, is associated with ipsilesional UE motor function in stroke patients.
• The integrity of specific corpus callosum subregions may differentially impact motor recovery depending on lesion side (dominant vs. non-dominant).
• Findings highlight the importance of interhemispheric pathways in motor recovery after stroke.