Neuroimaging Correlates of Post-Traumatic Stress Disorder in Traumatic Brain Injury: A Systematic Review of the Literature.

Neuroimaging is widely utilized in studying traumatic brain injury (TBI) and post-traumatic stress disorder (PTSD). The risk for PTSD is greater after TBI than after non-TBI trauma, and PTSD is associated with worse outcomes after TBI. Studying the neuroimaging correlates of TBI-related PTSD may provide insights into the etiology of both conditions and help identify those TBI patients most at risk of developing persistent symptoms. The objectives of this systematic review were to examine the current literature on neuroimaging in TBI-related PTSD, summarize key findings, and highlight strengths and limitations to guide future research. A Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols (PRISMA) compliant literature search was conducted in PubMed (MEDLINE®), PsycINFO, Embase, and Scopus databases prior to January 2022. The database query yielded 4486 articles, which were narrowed based on specified inclusion criteria to a final cohort of 16 studies, composed of 854 participants with TBI. There was no consensus regarding neuroimaging correlates of TBI-related PTSD among the included articles. A small number of studies suggest that TBI-related PTSD is associated with white matter tract changes, particularly in frontotemporal regions, as well as changes in whole-brain networks of resting-state connectivity. Future studies hoping to identify reliable neuroimaging correlates of TBI-related PTSD would benefit from ensuring consistent case definition, preferably with clinician-diagnosed TBI and PTSD, selection of comparable control groups, and attention to imaging timing post-injury. Prospective studies are needed and should aim to further differentiate predisposing factors from sequelae of TBI-related PTSD.

Behavioral and Emotional Dyscontrol Following Traumatic Brain Injury: A Systematic Review of Neuroimaging and Electrophysiological Correlates.

BACKGROUND: Behavioral and emotional dyscontrol commonly occur following traumatic brain injury (TBI). Neuroimaging and electrophysiological correlates of dyscontrol have not been systematically summarized in the literature to date. OBJECTIVE: To complete a systematic review of the literature examining neuroimaging and electrophysiological findings related to behavioral and emotional dyscontrol due to TBI. METHODS: A Preferred Reporting Items for Systematic Reviews and Meta-Analyses-compliant literature search was conducted in PubMed (MEDLINE), PsycINFO, EMBASE, and Scopus databases prior to May 2019. The database query yielded 4392 unique articles. These articles were narrowed based on specific inclusion criteria (e.g., clear TBI definition, statistical analysis of the relationship between neuroimaging and dyscontrol). RESULTS: A final cohort of 24 articles resulted, comprising findings from 1552 patients with TBI. Studies included civilian (n = 12), military (n = 10), and sport (n = 2) samples with significant variation in the severity of TBI incorporated. Global and region-based structural imaging was more frequently used to study dyscontrol than functional imaging or diffusion tensor imaging. The prefrontal cortex was the most common neuroanatomical region associated with behavioral and emotional dyscontrol, followed by other frontal and temporal lobe findings. CONCLUSIONS: Frontal and temporal lesions are most strongly implicated in the development of postinjury dyscontrol symptoms although they are also the most frequently investigated regions of the brain for these symptom categories. Future studies can make valuable contributions to the field by (1) emphasizing consistent definitions of behavioral and emotional dyscontrol, (2) assessing premorbid dyscontrol symptoms in subjects, (3) utilizing functional or structural connectivity-based imaging techniques, or (4) restricting analyses to more focused brain regions.

Neuroimaging Correlates of Syndromal Anxiety Following Traumatic Brain Injury: A Systematic Review of the Literature.

BACKGROUND: Traumatic brain injury (TBI) can precipitate new-onset psychiatric symptoms or worsen existing psychiatric conditions. To elucidate specific mechanisms for this interaction, neuroimaging is often used to study both psychiatric conditions and TBI. This systematic review aims to synthesize the existing literature of neuroimaging findings among patients with anxiety after TBI. METHODS: We conducted a Preferred Reporting Items for Systematic Review and Meta-Analyses-compliant literature search via PubMed (MEDLINE), PsychINFO, EMBASE, and Scopus databases before May, 2019. We included studies that clearly defined TBI, measured syndromal anxiety as a primary outcome, and statistically analyzed the relationship between neuroimaging findings and anxiety symptoms. RESULTS: A total of 5982 articles were retrieved from the systematic search, of which 65 studied anxiety and 13 met eligibility criteria. These studies were published between 2004 and 2017, collectively analyzing 764 participants comprised of 470 patients with TBI and 294 non-TBI controls. Imaging modalities used included magnetic resonance imaging, functional magnetic resonance imaging, diffusion tensor imaging, electroencephalogram, magnetic resonance spectrometry, and magnetoencephalography. Eight of 13 studies presented at least one significant finding and together reflect a complex set of changes that lead to anxiety in the setting of TBI. The left cingulate gyrus in particular was found to be significant in 2 studies using different imaging modalities. Two studies also revealed perturbances in functional connectivity within the default mode network. CONCLUSIONS: This is the first systemic review of neuroimaging changes associated with anxiety after TBI, which implicated multiple brain structures and circuits, such as the default mode network. Future research with consistent, rigorous measurements of TBI and syndromal anxiety, as well as attention to control groups, previous TBIs, and time interval between TBI and neuroimaging, are warranted. By understanding neuroimaging correlates of psychiatric symptoms, this work could inform future post-TBI screening and surveillance, preventative efforts, and early interventions to improve neuropsychiatric outcomes.

Procrastination as evidence of executive functioning impairment in college students.

Research addressing procrastination behavior has historically focused upon personality and situational factors to explain the nature of this problematic behavior. Although researchers have identified personality traits that are closely associated with procrastination behavior, the literature is sparse in addressing other possible explanations, particularly those related to brain functioning. Considering that procrastination is described with terms such as "poor time management," "lack of planning," and "poor judgment," amongst others, one might consider whether executive functioning systems are functioning adequately in these individuals. Individuals who demonstrate difficulties with executive functioning tend to share the same characteristics that are applied to those who procrastinate.Preliminary self-report research by Jurado and Rosselli found that undergraduates who reported higher levels of procrastination, also reported high levels of executive functioning difficulties. This research project replicated and extended these findings utilizing three common neuropsychological measures of executive functioning. The results from these measures demonstrated that individuals who showed impairment in executive functioning also reported difficulties with executive functioning and procrastination.