Upper limb and eye movement coordination during reaching tasks in people with stroke

Area of Science:

• Neuroscience
• Rehabilitation Science
• Movement Science

Background:

• Stroke often impairs upper limb function, affecting motor control.
• Understanding the interplay between limb and eye movements is crucial for rehabilitation.

Purpose of the Study:

• To investigate the relationship between upper limb and eye movements in stroke survivors during reaching tasks.
• To assess how upper limb impairment influences oculomotor behavior.

Main Methods:

• Recorded eye movements in 10 controls and 8 stroke participants during visual orienting and reaching tasks.
• Stroke participants performed reaching tasks with their less impaired limb, impaired limb without support, and impaired limb with support (gravitational support/electrical stimulation).

Main Results:

• Oculomotor control was intact in stroke survivors when not using the impaired limb.
• Reaching with the impaired limb led to decreased success, accuracy, and altered eye movement patterns, including increased gaze towards the limb.
• Upper limb support normalized hand-eye coordination patterns, resembling those of controls.

Conclusions:

• Upper limb motor deficits in stroke alter eye movement behavior during reaching.
• Providing upper limb support can modulate these eye movement changes and improve hand-eye coordination.
• Rehabilitation strategies should integrate motor and oculomotor assessments for stroke patients.