Lesion-dependent Cingulo-opercular Network and Language Network Integration in Post-stroke Aphasia.

Area of Science:

• Neuroscience
• Neurology
• Cognitive Science

Background:

• Poststroke aphasia (PSA) presents significant communication challenges.
• Understanding the neural underpinnings of language recovery is critical.
• The role of resting-state functional connectivity (rs-FC) and white matter integrity in PSA is an active area of research.

Purpose of the Study:

• To investigate differential impairment patterns in rs-FC between the cingulo-opercular network (CON) and language networks (LN) in PSA.
• To explore how language network (LN) lesion topography influences CON-LN connectivity and its relationship with behavior.
• To examine the mediating role of white matter integrity in these structure-function relationships.

Main Methods:

• Sixty-three first-time PSA patients were categorized into LN lesion-positive (LNL+) and LN lesion-negative (LNL-) groups.
• rs-FC between CON and LN was assessed using individualized and group-based template analyses.
• Correlations were performed between CON-LN rs-FC, verbal fluency, and white matter integrity (arcuate fasciculus [AF] and superior longitudinal fasciculus [SLF] subdivisions).

Main Results:

• No baseline intergroup differences in CON-LN rs-FC were found.
• In LNL+ patients, individualized CON-LN connectivity positively correlated with verbal fluency (r = .504, p = .009).
• In LNL+ patients, CON-LN connectivity negatively correlated with damage severity in AF and SLF subdivisions, indicating impaired white matter integrity impacts function.

Conclusions:

• CON-LN functional integration is vital for language recovery in PSA patients with direct LN damage.
• Specific white matter tracts, including anterior/long AF segments and SLF II/III, are key substrates supporting this integration.
• These findings underscore the importance of considering both lesion location and white matter integrity in understanding PSA and guiding rehabilitation strategies.