Effects of Blast-Induced mTBI on Neural Network Functional Connectivity
Blast-induced mild traumatic brain injuries (mTBI) is leading cause of sustained injury in today’s military service members. While injuries sustained in past wars consisted primarily of blunt force and penetrating head wounds, blast-induced mTBI is now a signature of modern warfare, primarily due to advanced weaponry, such as improvised explosive devices (IEDs).
Despite the increased prevalence of blast-induced mTBI, the pathophysiological effects of this type of injury are largely unknown. Thus, a group of researchers sought to use functional neuroimaging techniques to compare the neural network connectivity in different regions of the brain in active duty service members that have suffered blast-induced mTBI and struggle with persistent post-concussive symptoms (PCS) with healthy controls who have not suffered blast-induced mTBI. Neural connectivity was measured during a 5 minute resting-state recording using magnetoencephalography (MEG), which can be used to detect discrepancies in connectivity by measuring neuronal activity. Due to its ability to measure neuronal activity at different frequencies, MEG allows researchers to decipher the parts of the brain that are most affected by blast-induced mTBI.
In this study, Huang et al found that service members who experienced blast-induced mTBI and have persistent PCS have significantly increased activity in beta activity, which corresponds to increased functional connectivity in regions of the brain that regulate memory and executive function as compared to the healthy participants. Follow-up neuropsychological screening indicates that increased neural activity in these brain regions corresponds to lower performance in executive function tasks. To better understand mTBI-related differences in functional connectivity, future studies should include a comparison between service members who have experienced blast-induced mTBI with and without PCS.
Huang, Ming-Xiong, et al. “Resting-state Magnetoencephalography Reveals Different Patterns of Aberrant Functional Connectivity in Combat-Related Mild Traumatic Brain Injury.” Journal of Neurotrauma. (December 2016).