Attention Please! Unravelling the link between brain network connectivity and cognitive attention following acquired brain injury: A systematic review of structural and functional measures

Abstract

Traumatic brain injury (TBI) and stroke are the most common causes of acquired brain injury (ABI), annually affecting 69 million and 15 million people, respectively. Following ABI, the relationship between brain network disruption and common cognitive issues including attention dysfunction is heterogenous. We systematically reviewed 43 studies which reported correlations between attention and connectivity. Across all ages and stages of recovery, following TBI, greater attention was associated with greater structural efficiency within/between executive network (ECN), salience network (SN) and default mode network (DMN) and greater functional connectivity (fc) within/between ECN and DMN, indicating DMN interference. Following stroke, greater attention was associated with greater structural connectivity (sc) within ECN; or greater fc within the dorsal attention network (DAN). In childhood ABI populations, decreases in structural network segregation were associated with greater attention. Longitudinal recovery from TBI was associated with normalisation of DMN activity, and in stroke, normalisation of DMN and DAN activity. Results improve clinical understanding of attention-related connectivity changes following ABI. Recommendations for future research include increased use of EEG and fNIRS to measure connectivity at the point of care, standardized attention and connectivity outcome measures and analysis pipelines, detailed reporting of patient symptomatology, and casual analysis of attention-related connectivity using brain stimulation.