Cortical plasticity in amyotrophic lateral sclerosis: motor imagery and function

Area of Science:

• Neuroscience
• Motor Control Research
• Biomedical Engineering

Background:

• Cortical motor networks are closely linked to motor performance.
• These networks can be activated even in patients with severe motor disabilities.

Purpose of the Study:

• To investigate the longitudinal impact of progressive motoneuron degeneration on motor imagery and function.
• To analyze changes in cortical representation in amyotrophic lateral sclerosis (ALS).

Main Methods:

• Functional magnetic resonance imaging (fMRI) was used to study 14 ALS patients and 15 healthy controls.
• A grip force paradigm involving imagery and execution tasks was employed.
• Subgroup analysis was conducted after 6 months.

Main Results:

• Motor imagery activated similar neural networks (primary motor, premotor, supplementary motor cortex) in both ALS patients and controls.
• ALS patients exhibited stronger activation in premotor and primary motor areas during imagery and execution.
• After 6 months, persistent differences were observed, with increased activity in the precentral gyrus and a frontoparietal network for motor imagery in patients, correlating with impairment.

Conclusions:

• ALS patients demonstrate an ongoing compensatory process in higher-order motor systems to counteract functional loss.
• Increased activity in specific brain networks during motor imagery may facilitate brain-computer interface control for communication and prosthetic devices in severely disabled ALS patients.