AUTHOR=Newsome Mary R. , Martindale Sarah L. , Davenport Nicholas , Dennis Emily L. , Diaz Marlene , Esopenko Carrie , Hodges Cooper , Jackson George R. , Liu Qisheng , Kenney Kimbra , Mayer Andrew R. , Rowland Jared A. , Scheibel Randall S. , Steinberg Joel L. , Taylor Brian A. , Tate David F. , Werner J. Kent , Walker William C. , Wilde Elisabeth A. TITLE=Subcortical functional connectivity and its association with walking performance following deployment related mild TBI JOURNAL=Frontiers in Neurology VOLUME=14 YEAR=2023 URL=https://www.frontiersin.org/journals/neurology/articles/10.3389/fneur.2023.1276437 DOI=10.3389/fneur.2023.1276437 ISSN=1664-2295 ABSTRACT=Introduction

The relation between traumatic brain injury (TBI), its acute and chronic symptoms, and the potential for remote neurodegenerative disease is a priority for military research. Structural and functional connectivity (FC) of the basal ganglia, involved in motor tasks such as walking, are altered in some samples of Service Members and Veterans with TBI, but any behavioral implications are unclear and could further depend on the context in which the TBI occurred.

Methods

In this study, FC from caudate and pallidum seeds was measured in Service Members and Veterans with a history of mild TBI that occurred during combat deployment, Service Members and Veterans whose mild TBI occurred outside of deployment, and Service Members and Veterans who had no lifetime history of TBI.

Results

FC patterns differed for the two contextual types of mild TBI. Service Members and Veterans with deployment-related mild TBI demonstrated increased FC between the right caudate and lateral occipital regions relative to both the non-deployment mild TBI and TBI-negative groups. When evaluating the association between FC from the caudate and gait, the non-deployment mild TBI group showed a significant positive relationship between walking time and FC with the frontal pole, implicated in navigational planning, whereas the deployment-related mild TBI group trended towards a greater negative association between walking time and FC within the occipital lobes, associated with visuo-spatial processing during navigation.

Discussion

These findings have implications for elucidating subtle motor disruption in Service Members and Veterans with deployment-related mild TBI. Possible implications for future walking performance are discussed.