Prolonged eye-hand decoupling deficits in young adults with a history of concussion from adolescence.

Previous studies reported that adolescents with a sport-related concussion history showed prolonged visuomotor deficits during an eye-hand decoupling task until around 1.5-2 years post-event. The present study expands this work, examining whether such deficits do or do not emerge when testing individuals in young adulthood, i.e. later post-event. Twenty-one non-athlete college students with sport-related concussion history from adolescence (CH; M = 21 yrs.; M = 46 months post-concussion, range 10-90 months) and twenty controls with no history of concussion (NoH; M = 21 yrs.) performed two touchscreen-based visuomotor tasks. It included a coupled task where eyes and hand moved in similar directions, and decoupled-task with eyes and hand going to different directions. Movement planning (e.g. reaction time, initial direction error) and execution (e.g. movement time, path length) related variables were analyzed in both groups and conditions. Movement execution measures were similar for both groups and conditions (all p > 0.05). However, movement planning was impaired in the CH participants in the eye-hand decoupling condition (p < 0.05). CH's initial direction error was larger (i.e. worse spatial movement planning) than in the NoH group. Although movement execution deficits shown in earlier work in youth were not present in young adults, the present results suggest that a sport-related concussion sustained in adolescence can lead to prolonged deficits with spatial movement planning processes while performing eye-hand decoupling tasks about four years post-injury. Further research should investigate whether these deficits continue into adulthood and expand control on time since concussion and number of concussion metrics.Highlights Young adult college students with a history of a sport-related concussion from adolescence, tested about four years post-incident, showed spatial movement preparation deficits during an eye-hand decoupling visuomotor task.Eye-hand reversal decoupling errors also correlated with time since concussion in those with concussion history.These prolonged eye-hand decoupling deficits may emerge with ongoing time post-event, as comparable deficits were absent in previous work where youth were tested sooner post-injury.Our current findings point towards long-lasting performance impairments in young adult non-athletes after a sport-related concussion from adolescence.

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.