Exploring relationships between abnormal within-network functional connectivity, preoperative brain tumor variables, and neuropsychological test scores.

Objective: Neuropsychological symptoms in people with brain tumors are common; however, they are often incompletely explained by tumor variables (such as anatomical location, size, or grade) and may be more directly related to changes in large-scale functional network connectivity. Here we examine these relationships. Methods: Fifty-one participants underwent pre-operative resting-state functional MRIs and three neuropsychological tests-Trail Making Test-Part-B (TMT-B), WAIS-IV Digit-Span Sequencing (WAIS-DS), and Controlled Oral Word Association Test (COWAT). Within-network functional connectivity of the central executive (CEN), default mode (DMN), language (LANG), and salience (SN) networks were compared to healthy controls. Spearman correlations (ρ) were calculated between neuropsychological z-scores, abnormal (>2 standard deviations from control means) within-network connectivity, and tumor variables while controlling for multiple comparisons. Exploratory, statistical mediation analyses then evaluated if relevant tumor variables affected neuropsychological performance via changes in functional connectivity. Results: Significant correlations included: (1) WAIS-DS performance to lesional-SN ( Conclusions: Our data support the hypothesis that functional network connectivity may explain some neuropsychological heterogeneity across otherwise anatomically and oncologically similar cases. Notably, more abnormal connectivity correlated with better performance, suggesting compensatory reorganization may be at least partially responsible.