Abstract
Blast-related mild traumatic brain injury (mTBI) is commonly reported among military personnel and combat veterans, and neuropsychological outcomes of blast concussion has been a topic of frequent investigation in recent years. Debate exists as to whether a remote history of blast mTBI and/or other potential contributing factors (e.g., chronic psychological difficulties, such as post-traumatic stress) accounts for neuropsychological impairments that are demonstrated in the late stage of self-reported injury (e.g., months or years post-deployment). The current meta-analysis examined the overall neuropsychological effects of remote blast concussion by comparing performances of those with blast mTBI histories relative to two comparison groups: (1) participants with histories of non-blast-related mTBI (6 studies) and (2) participants without any lifetime history of mTBI (5 studies). Overall neuropsychological performance of blast-related mTBI (n = 1031) relative to non-blast-related mTBI (n = 1809) suggested a small overall effect (d = .14), while studies that compared neuropsychological performances of blast-related mTBI (n = 1086) and the no mTBI condition (n = 19565) was negligible (d = .05). Effect sizes generated across eight cognitive domains were also negligible in the blast-related/non-blast-related mTBI condition, save for a small effect noted in visuospatial abilities (d = .23). Small to medium effects were noted across select cognitive domains (e.g., attention, visuospatial abilities) in the blast versus no-mTBI condition. Implications and limitations of these findings are discussed.