Inhibition explains the relationship between the efficiency of brain networks and adaptive outcomes in pediatric brain tumor survivors.

Abstract

Research has found altered brain network connectivity in pediatric brain tumor survivors. Efficient brain networks are critical for performing complex behaviors involved in adaptive functioning (AF). The present study explored relationships between structural brain network characteristics and AF in survivors. We examined whether this relationship is mediated by inhibition and cognitive flexibility, important cognitive abilities for AF. Thirty-seven young adult survivors and 37 matched healthy controls (HC; overall Mage = 23.1, SD = 4.9) underwent neuropsychological assessment. Informants completed the Scales of Independent Behavior-Revised (SIB-R) interview. Color-Word Interference Inhibition and Inhibition-Switching from the Delis-Kaplan Executive Functioning System measured inhibition and cognitive flexibility performance. Deterministic tractography was performed on diffusion-weighted imaging, the Automated Anatomical Labeling (AAL) atlas defined nodes, and edges were the average fractional anisotropy between nodes. Global efficiency (GE), average clustering coefficient (CC), and density were computed. Partial correlations and analysis of indirect effects were conducted. There were significant relationships between GE and all SIB-R scales, but findings with CC were limited to two subscales. Inhibition was moderately related to GE, but this was no longer significant after Holm's correction. Cognitive flexibility was not found to be related to graph metrics. Finally, significant indirect effects were found such that inhibition explained the relationship between GE and SIB-R Motor and Social/Communication. Based on these findings, higher levels of brain network integration, as measured by GE, is related to inhibition in survivors, which facilitates proficient adaptive motor and social/communication skills. Future work should investigate tumor location and treatment factors as potential moderators of the relationships found in this study to better understand specific risk factors in this group. (PsycInfo Database Record (c) 2022 APA, all rights reserved).