Abstract TP320: The Effect of Stroke Type and Lateralization on Longitudinal Cognitive Changes During Stroke Recovery

This project, to our knowledge, is the first longitudinal study to simultaneously examine how stroke lateralization (right (RH) vs left (LH) hemisphere) and type (ischemic (IS) vs hemorrhagic (HH)) uniquely influence cognitive recovery, specifically verbal learning and visuospatial memory. Understanding these distinctions may inform more effective post-stroke therapies. From a larger cohort, this pilot study recruited 56 English-speaking post-stroke patients (~54 years old) who underwent the Hopkins Verbal Learning Test (HVLT) and Brief Visuospatial Memory Test (BVMT) across acute, subacute, and chronic phases of recovery. Participants were stratified by lesion type and location, with groups matched for age, stroke timing, lesion volume, and standard care hours. Change in HVLT and BVMT recall T-scores were assessed using paired two-tailed t-tests for within-group comparisons and unpaired one-tailed t-tests for between-group comparisons (e.g. LH vs RH, IS vs HH). Hemispheric differences within stroke types were also examined. LH participants showed significant BVMT and HVLT improvements from acute to subacute phases (p<0.05), and a greater change in HVLT recovery than RH participants (p<0.05; Fig. 1). IS vs HH comparisons revealed lower change in HVLT scores in the IS group (p<0.05; Fig. 2), and within the ischemic group, BVMT improvements were seen between acute and chronic stages (p<0.05). Within the IS group, LH participants were more impaired in HVLT during the acute phase (p<0.05; Fig. 3). In the HH group, LH participants showed greater change in BVMT recovery over time (p<0.05; Fig. 3). Verbal memory is primarily supported by the left hemisphere, which may explain why LH strokes resulted in greater verbal deficits, leaving more room for acute improvement. Recovery in LH cases was often non-linear, reflecting limited compensatory mechanisms and late-stage neurodegeneration. Ischemic strokes also resulted in more severe acute verbal deficits, possibly because critical left-hemisphere regions are more vulnerable to ischemia due to their high metabolic demand and limited collateral circulation. Meanwhile, RH HH strokes showed poorer visuospatial recovery, likely due to irreversible damage of right-lateralized cortical areas subserving visuospatial memory. These findings underscore the need for lesion-driven treatment and acute cognitive screening to improve long-term outcomes. Future work will focus on how comorbidities affect cognitive outcomes post-stroke.