Relationship between functional connectivity and sensory impairment: red flag or red herring?

Area of Science:

• Neuroimaging
• Neuroscience
• Pediatric Neurology

Background:

• Resting-state functional magnetic resonance imaging (fMRI) assesses brain network connectivity.
• Understanding somatosensory network connectivity in pediatric brain lesions is limited.
• Previous work focused on motor networks in children with hemiparesis.

Purpose of the Study:

• Validate resting-state fMRI for somatosensory network analysis in pediatric brain lesions.
• Investigate the link between somatosensory network connectivity, sensory deficits, and gray matter (GM) volume.
• Compare findings between children with middle cerebral artery (MCA) strokes and periventricular lesions (PL).

Main Methods:

• Utilized interleaved resting-state fMRI data from blocked designs.
• Validated the approach by assessing "crossed-over" connectivity between cerebral cortex and cerebellum.
• Quantified gray matter (GM) volume in primary (S1) and secondary (S2) somatosensory cortices.

Main Results:

• Successfully replicated the "crossed-over" pattern of functional connectivity.
• The MCA group showed greater sensory deficits and reduced connectivity in lesioned S2 compared to the PL group.
• The difference in connectivity between MCA and PL groups disappeared when accounting for GM volume loss.

Conclusions:

• Resting-state fMRI is applicable for analyzing functional connectivity in patients with brain lesions.
• Reduced somatosensory network connectivity correlates with sensory deficits in pediatric brain lesions.
• Gray matter damage fully explains the observed reductions in functional connectivity.