Citation

Nathan DE, Bellgowan JF, Oakes T, French LM, Nadar SR, Sham EB, Liu W, Riedy G. Brain Connect. 2016; 6(5): 389-402.

Affiliation

National Intrepid Center of Excellence, Neuroimaging, Bethesda, Maryland, United States ; gerard.p.riedy.civ@mail.mil.

Copyright

(Copyright © 2016, Mary Ann Liebert Publishers)

DOI

10.1089/brain.2015.0403

PMID

26956452

Abstract

In the global war on terror, the increased use of improvised explosive devices has resulted in increased incidence of blast-related mild Traumatic Brain Injury (mTBI). Diagnosing mTBI is both challenging and controversial due to heterogeneity of injury location, trauma intensity, transient symptoms and absence of focal biomarkers on standard clinical imaging modalities. The goal of this study is to identify a brain biomarker that is sensitive to mTBI injury. Research suggests the thalamus may be sensitive to changes induced by mTBI. A significant number of connections to and from various brain regions converge at the thalamus. In addition, the thalamus is involved in information processing, integration and regulation of specific behaviors and mood. In this study, changes in task free thalamic networks as quantified by graph theory measures in mTBI blast (N=186), mTBI non-blast (N=80) and controls (N=21) were compared.

RESULTS show that the blast mTBI group had significant hyper-connectivity as compared to the controls and non-blast mTBI group. However, after controlling for post traumatic stress symptoms (PTS), the blast mTBI group was not different from the controls, but the non-blast mTBI group showed significant hypo-connectivity. The results suggest that there are differences in the mechanisms of injury related to mTBI as reflected in the architecture of the thalamic networks. However, the effect of PTS symptoms and its relationship to mTBI is difficult to distinguish and warrants more research.

Language: en