Lesion-dependent Cingulo-opercular Network and Language Network Integration in Poststroke Aphasia

This study explores differential impairment patterns in resting-state functional connectivity (rs-FC) between the cingulo-opercular network (CON) and canonical language networks (LN) in poststroke aphasia (PSA), emphasizing structure–function relationships mediated by white matter integrity. It specifically investigates how LN lesion topography modulates CON–LN connectivity and behavioral correlates. Sixty-three first-time PSA patients were divided into LN lesion-positive (LNL+, n = 31) and negative (LNL−, n = 32) groups based on lesion volume (>1 cm3) within the canonical LN. Using lesion-based individualized ROIs and group-based template rs-FC, the CON–LN rs-FC was correlated with verbal fluency and white matter integrity metrics, with particular focus on arcuate fasciculus (AF) and superior longitudinal fasciculus (SLF) subdivisions in the LNL+ and LNL− groups, respectively. Although no intergroup differences in CON–LN rs-FC were observed at baseline, distinct lesion-dependent patterns emerged. In LNL+ patients, individualized CON–LN connectivity was positively correlated with verbal fluency (r = .504, p = .009) and negative correlation with the damage severity of the AF subdivisions (anterior: r = −.601, p < .001; long: r = −.426, p = .024) and SLF subdivisions (SLF II: r = −.483, p = .011; III: r = −.664, p < .001). However, the LNL− patients lacked significant structure–function–behavior associations. The group-based template analysis also detected no significant correlations in either group. Our findings implicate the critical role of CON–LN functional integration for language recovery in PSA patients with direct LN damage. The anterior/long AF segments and SLF II/III are key white matter substrates supporting this functional integration.