Central perception of position sense involves a distributed neural network - Evidence from lesion-behavior analyses.

Area of Science:

• Neuroscience
• Motor Control
• Neurorehabilitation

Background:

• Proprioception, or limb position sense, is crucial for motor control and perception.
• Current understanding of central processing for position sense is limited, relying on animal models and case studies.
• Stroke can significantly impact proprioceptive abilities, affecting daily motor functions.

Purpose of the Study:

• To investigate the neural correlates of position sense in a large cohort of stroke survivors.
• To identify brain regions critical for processing limb position using statistical lesion-behavior mapping.
• To explore whether different components of position sense (variability, workspace area, location) have distinct neuroanatomical underpinnings.

Main Methods:

• Employed a statistical lesion-behavior analysis approach in a large sample of acute stroke patients.
• Utilized an arm position matching task to assess position sense.
• Excluded participants with confounding ipsilesional motor or sensory impairments through clinical and robotic assessments.

Main Results:

• Identified critical brain regions for position sense, including the posterior parietal cortex, transverse temporal gyrus, and arcuate fasciculus.
• Demonstrated that position sense is dissociable into components: spatial variability, perceived workspace area, and perceived workspace location.
• Each component of position sense was associated with unique neuroanatomical correlates.

Conclusions:

• The findings expand the understanding of the neural basis of proprioception and limb position sense.
• Identified novel brain areas, beyond classical proprioceptive regions, involved in processing position sense.
• Highlights the potential for targeted neurorehabilitation strategies focusing on specific components of position sense deficits post-stroke.