Abstract
This review focuses on the application of functional magnetic resonance imaging (fMRI) to the investigation of blast-related traumatic brain injury (bTBI). Relatively little is known about the exact mechanisms of neurophysiological injury and pathological and functional sequelae of bTBI. Furthermore, in mild bTBI, standard anatomical imaging techniques (MRI and computed tomography) generally fail to show focal lesions and most of the symptoms present as subjective clinical functional deficits. Therefore, an objective test of brain functionality has great potential to aid in patient diagnosis and provide a sensitive measurement to monitor disease progression and treatment. The goal of this review is to highlight the relevant body of blast-related TBI literature and present suggestions and considerations in the development of fMRI studies for the investigation of bTBI. The review begins with a summary of recent bTBI publications followed by discussions of various elements of blast-related injury. Brief reviews of some fMRI techniques that focus on mental processes commonly disrupted by bTBI, including working memory, selective attention, and emotional processing, are presented in addition to a short review of resting state fMRI. Potential strengths and weaknesses of these approaches as regards bTBI are discussed. Finally, this review presents considerations that must be made when designing fMRI studies for bTBI populations, given the heterogeneous nature of bTBI and its high rate of comorbidity with other physical and psychological injuries.
Highlights
BTBI OCCURRENCE Traumatic brain injury following blast exposure is quite prevalent in soldiers returning from the conflicts in Iraq and Afghanistan
Using seed regions based on major depressive disorder (MDD)-related changes in gray matter volume, Ma et al (2012) found alterations in resting state functional connectivity between the middle temporal gyrus and portions of the default mode network” (DMN) and between the right caudate and portions of the frontal cortex associated with MDD, while Guo et al (2012) saw decreased crosshemispheric signal correlation in the mPFC and PCC in patients with MDD
Given the rates of comorbidity of post-traumatic stress disorder (PTSD) and MDD with mTBI and the effects these disorders can have on brain activation patterns in response to a variety of functional magnetic resonance imaging (fMRI) tasks, measurements of PTSD and MDD presence or severity [such as the PTSD checklist (Weathers et al, 1993) and the Beck Depression Inventory 2 (Beck et al, 1996)] should be taken on subjects involved in blast-related traumatic brain injury (bTBI) fMRI studies
Summary
Brain injury associated with secondary and tertiary blast effects should be considered when designing and performing neuroimaging studies with patient populations who have suffered blast-related TBI. While both groups were seen to activate similar general regions when carrying out the N-back task, the specific extent of activation corresponding to different levels of working memory challenge differed between healthy controls and TBI patients.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
