Neuropsychological function 23 years after mild traumatic brain injury: a comparison of outcome after paediatric and adult head injuries

Use of donepezil for neurocognitive recovery after brain injury in adult and pediatric populations: a scoping review

There are few pharmacologic options for the treatment of cognitive deficits associated with traumatic brain injury in pediatric patients. Acetylcholinesterase inhibitors such as donepezil have been evaluated in adult patients after traumatic brain injury, but relatively less is known about the effect in pediatric populations. The goal of this review is to identify knowledge gaps in the efficacy and safety of acetylcholinesterase inhibitors as a potential adjuvant treatment for neurocognitive decline in pediatric patients with traumatic brain injury. Investigators queried PubMed to identify literature published from database inception through June 2023 describing the use of donepezil in young adult traumatic brain injury and pediatric patients with predefined conditions. Based on preselected search criteria, 340 unique papers were selected for title and abstract screening. Thirty-two records were reviewed in full after eliminating preclinical studies and papers outside the scope of the project. In adult traumatic brain injury, we review results from 14 papers detailing 227 subjects where evidence suggests donepezil is well tolerated and shows both objective and patient-reported efficacy for reducing cognitive impairment. In children, 3 papers report on 5 children recovering from traumatic brain injury, showing limited efficacy. An additional 15 pediatric studies conducted in populations at risk for cognitive dysfunction provide a broader look at safety and efficacy in 210 patients in the pediatric age group. Given its promise for efficacy in adults with traumatic brain injury and tolerability in pediatric patients, we believe further study of donepezil for children and adolescents with traumatic brain injury is warranted.

Multifaceted neural and vascular pathologies after pediatric mild traumatic brain injury

Dynamic changes in neurodevelopment and cognitive functioning occur during adolescence, including a switch from reactive to more proactive forms of cognitive control, including response inhibition. Pediatric mild traumatic brain injury (pmTBI) affects these cognitions immediately post-injury, but the role of vascular versus neural injury in cognitive dysfunction remains debated. This study consecutively recruited 214 sub-acute pmTBI (8-18 years) and age/sex-matched healthy controls (HC; N = 186), with high retention rates (>80%) at four months post-injury. Multimodal imaging (functional MRI during response inhibition, cerebral blood flow and cerebrovascular reactivity) assessed for pathologies within the neurovascular unit. Patients exhibited increased errors of commission and hypoactivation of motor circuitry during processing of probes. Evidence of increased/delayed cerebrovascular reactivity within motor circuitry during hypercapnia was present along with normal perfusion. Neither age-at-injury nor post-concussive symptom load were strongly associated with imaging abnormalities. Collectively, mild cognitive impairments and clinical symptoms may continue up to four months post-injury. Prolonged dysfunction within the neurovascular unit was observed during proactive response inhibition, with preliminary evidence that neural and pure vascular trauma are statistically independent. These findings suggest pmTBI is characterized by multifaceted pathologies during the sub-acute injury stage that persist several months post-injury.

Brain functional connectivity in children with a mild traumatic brain injury: A scoping review

INTRODUCTION

The occurrence of mild traumatic brain injury(mTBI) is estimated at 0,2-0,3% cases annually. Following a mTBI, some children experience persistent symptoms, and functional connectivity(FC) changes may be implicated. However, characteristics of FC have not been widely described in this population. This scoping review aimed to identify and understand the impacts of mTBI on EEG-measured FC in children, provide an overview of the available literature, detail analysis techniques, and describe gaps in the research.

METHODS

PubMed, Web of Science, Medline, Embase, ProQuest and CINAHL were searched up to June 25, 2023, with the terms child, mTBI, EEG, FC, and their synonyms. Ten studies were identified.

RESULTS

Five studies reported significant differences between the mTBI group and controls. In addition to group differences, six studies reported significant variation over time. Brain Network Analysis(BNA), utilized in seven studies, was the primary FC analysis recorded. Two of the five studies that reported significant differences following mTBI utilized the BNA. The other three applied alternative analysis methods.

DISCUSSION

FC assessment based on EEG can identify some differences in children with mTBI. BNA was more useful in following changes over time. Further research is suggested, considering the limited age range and number of retrieved studies.

Prolonged duration of post-traumatic amnesia: A sensitive classification for predicting cognitive outcomes in children recovering from traumatic brain injury

OBJECTIVE

A paucity of data exists regarding the duration of post-traumatic amnesia (PTA) as a predictor of cognitive functioning among children after traumatic brain injury (TBI). The study aimed to assess the relationship between PTA duration and areas of neurocognitive function among the pediatric population in the sub-acute phase of recovery and rehabilitation.

METHODS

Data were collected from medical files on 103 children aged 5.5-16.5 hospitalized at a pediatric rehabilitation department with a diagnosis of moderate-severe TBI (msTBI) between the years 2004-2019. The Children Orientation and Amnesia Test was used to evaluate PTA duration. Measures of high-order cognitive abilities of attention and executive function were collected using the Test of Everyday Attention-Child version (TEA-Ch).

RESULTS

Three PTA duration groups were assembled out of a cluster analysis: "Long PTA" (M = 21 days), "Very Long PTA" (M = 47 days), and "Extremely Long PTA" (M = 94 days). Analyses revealed that the "Long PTA" group preformed significantly better than the "Very Long PTA" and "Extremely Long PTA" groups on all TEA-Ch measures, that is, Selective Attention, Attentional Control Switching, and Sustained Attention.

CONCLUSIONS

This study is the first to demonstrate that PTA duration is a useful predictor of high-order cognitive functions among children with msTBI in the sub-acute phase of recovery and rehabilitation. The findings emphasize the importance of using a more sensitive classification of prolonged PTA durations to improve outcome prediction and allocation of resources to those who can benefit most after severe brain injuries.

Predictive validity of the Westmead Post-Traumatic Amnesia Scale for functional outcomes in school-aged children who sustained traumatic brain injury

The Westmead Post-Traumatic Amnesia Scale (WPTAS) is routinely used for the assessment of post-traumatic amnesia (PTA) in children who sustained traumatic brain injury (TBI). Yet, the WPTAS' predictive validity for functional outcomes is largely unknown. We aimed to determine whether PTA duration measured by the WPTAS (i) differentially predicts functional outcomes and (ii) contributes to predictions of outcomes beyond the Glasgow Coma Scale (GCS) in children who sustained TBI. Participants were children and adolescents with moderate-to-severe TBI (n = 55) aged 8-15 years. PTA duration was assessed with the WPTAS. Outcomes at the first outpatient follow-up were scored on the Kings Outcome Scale for Childhood Head Injury (KOSCHI) and the TBI Outcome Domain Scale-Extended (ODS-E). Longer PTA and lower GCS were both significantly correlated with worse (i) global outcomes: presence of disability on the KOSCHI and lower score on the ODS-E and (ii) select specific outcomes on the ODS-E: mobility, mood and cognition. PTA duration predicted cognitive outcome on the ODS-E independently, beyond GCS. Together, PTA duration and GCS, predicted the global KOSCHI outcome, as well as the ODS-E mobility and mood outcomes. Neither GCS nor PTA duration correlated with the ODS-E communication, impulsivity/disinhibition, headache, fatigue, sensory impairments or somatic complaints outcomes. PTA duration measured by the WPTAS is a significant unique predictor of functional cognitive outcomes in children who sustained moderate-to-severe TBI, and in combination with the GCS, a significant predictor of global, and several specific functional outcomes.

The Australian and New Zealand brain injury lifespan cohort protocol: Leveraging common data elements to characterise longitudinal outcome and recovery

INTRODUCTION

Cognitive, behavioural, academic, mental health and social impairments are common following paediatric traumatic brain injury (TBI). However, studies are often reliant on small samples of children drawn from narrow age bands, and employ highly variable methodologies, which make it challenging to generalise existing research findings and understand the lifetime history of TBI.

METHOD AND ANALYSIS

This study will synthesise common data sets from national (Victoria, New South Wales, Queensland) and international (New Zealand) collaborators, such that common data elements from multiple cohorts recruited from these four sites will be extracted and harmonised. Participant-level harmonised data will then be pooled to create a single integrated data set of participants including common cognitive, social, academic and mental health outcome variables. The large sample size (n=1816), consisting of participants with mild, moderate and severe TBI, will provide statistical power to answer important questions that cannot be addressed by small, individual cohorts. Complex statistical modelling, such as generalised estimation equation, multilevel and latent growth models, will be conducted.

ETHICS AND DISSEMINATION

Ethics approval was granted by the Human Research Ethics Committee (HREC) of the Royal Children's Hospital (RCH), Melbourne (HREC Reference Number 2019.168). The approved study protocol will be used for all study-related procedures. Findings will be translated into clinical practice, inform policy decisions, guide the appropriate allocation of limited healthcare resources and support the implementation of individualised care.

Effectiveness of non-pharmacological treatments for vestibular and oculomotor dysfunction in patients with persistent post-concussive symptoms: protocol for a systematic review and meta-analysis

INTRODUCTION

Concussion is a form of mild traumatic brain injury that disrupts brain function. Although symptoms are mostly transient, recovery can be delayed and result in persistent postconcussive symptoms (PPCS). Vestibular and oculomotor dysfunction are among the most debilitating impairments associated with PPCS. However, pharmacological interventions for these impairments are associated with deleterious side effects. Accordingly, increasing research has examined the utility of non-pharmacological interventions for PPCS. The aim of this review is to synthesise and evaluate the effectiveness of non-pharmacological interventions for the treatment of vestibular and oculomotor dysfunction for patients with PPCS.

METHODS AND ANALYSIS

Systematic searches of MEDLINE, PubMed, Web of Science and Scopus will identify randomised controlled trials employing non-pharmacological treatments for vestibular and/or oculomotor dysfunction for PPCS. Such interventions may include, but are not limited to, vestibular rehabilitation, optokinetic stimulation and vestibulo-ocular reflex exercises. Assessments of oculomotor function will include versional eye movements, vergence eye movements, visual-fixation movements and accommodation response. Assessments of vestibular function will include the Fukuda Step test, functional balance tests, force displacement tests, and subjective reports of balance disruption or vertigo. Where appropriate, meta-analyses of standardised mean differences will be conducted using a random effects model for continuous outcomes. For dichotomous outcomes (improved vs not improved following treatment), effects will be expressed as relative risk. The impact of heterogeneity will be calculated using the I² statistic. The Physiotherapy Evidence Database scale will be used to determine the methodological quality of individual studies and Grading of Recommendations, Assessment, Development and Evaluations used to assess the certainty and quality of evidence for each outcome.

ETHICS AND DISSEMINATION

Ethical approval is not required for this review. Findings will be disseminated through peer-reviewed publications and conference presentations.

PROSPERO REGISTRATION NUMBER

CRD42021254720.

A Scoping Review of Magnetic Resonance Modalities Used in Detection of Persistent Postconcussion Symptoms in Pediatric Populations

Up to 30% of youth with concussion experience PPCSs (PPCS) lasting 4 weeks or longer, and can significantly impact quality of life. Magnetic resonance imaging (MRI) has the potential to increase understanding of causal mechanisms underlying PPCS. However, there are no clear modalities to assist in detecting PPCS. This scoping review aims to synthesize findings on utilization of MRI among children and youth with PPCS, and summarize progress and limitations. Thirty-six studies were included from 4907 identified papers. Many studies used multiple modalities, including (1) structural (n = 27) such as T1-weighted imaging, diffusion weighted imaging, and susceptibility weighted imaging; and (2) functional (n = 23) such as functional MRI and perfusion-weighted imaging. Findings were heterogeneous among modalities and regions of interest, which warrants future reviews that report on the patterns and potential advancements in the field. Consideration of modalities that target PPCS prediction and sensitive modalities that can supplement a biopsychosocial approach to PPCS would benefit future research.

Technical feasibility of using auditory phase-targeted stimulation after pediatric severe traumatic brain injury in an intensive care setting

Background

Supplementary treatment options after pediatric severe traumatic brain injury (TBI) are needed to improve neurodevelopmental outcome. Evidence suggests enhancement of brain delta waves via auditory phase-targeted stimulation might support neuronal reorganization, however, this method has never been applied in analgosedated patients on the pediatric intensive care unit (PICU). Therefore, we conducted a feasibility study to investigate this approach: In a first recording phase, we examined feasibility of recording over time and in a second stimulation phase, we applied stimulation to address tolerability and efficacy.

Methods

Pediatric patients (> 12 months of age) with severe TBI were included between May 2019 and August 2021. An electroencephalography (EEG) device capable of automatic delta wave detection and sound delivery through headphones was used to record brain activity and for stimulation (MHSL-SleepBand version 2). Stimulation tolerability was evaluated based on report of nurses, visual inspection of EEG data and clinical signals (heart rate, intracranial pressure), and whether escalation of therapy to reduce intracranial pressure was needed. Stimulation efficacy was investigated by comparing EEG power spectra of active stimulation versus muted stimulation (unpaired t-tests).

Results

In total, 4 out of 32 TBI patients admitted to the PICU (12.5%) between 4 and 15 years of age were enrolled in the study. All patients were enrolled in the recording phase and the last one also to the stimulation phase. Recordings started within 5 days after insult and lasted for 1–4 days. Overall, 23–88 h of EEG data per patient were collected. In patient 4, stimulation was enabled for 50 min: No signs of patient stress reactions were observed. Power spectrums between active and muted stimulation were not statistically different (all P > .05).

Conclusion

Results suggests good feasibility of continuously applying devices needed for auditory stimulation over multiple days in pediatric patients with TBI on PICU. Very preliminary evidence suggests good tolerability of auditory stimuli, but efficacy of auditory stimuli to enhance delta waves remains unclear and requires further investigation. However, only low numbers of severe TBI patients could be enrolled in the study and, thus, future studies should consider an international multicentre approach.

Adult Cognitive Outcomes Following Childhood Mild Traumatic Brain Injury: A Scoping Review

OBJECTIVE

This review aimed to (1) summarize the existing literature regarding cognitive outcomes in adults with a history of pediatric mild traumatic brain injury (mTBI) and (2) identify gaps in the literature to provide directions for future research.

PARTICIPANTS

Participants sustained mTBI in childhood (0-17 years of age) and underwent cognitive assessment in adulthood (older than 18 years) at least 1 year postinjury.

DESIGN

MEDLINE Ovid and PsycINFO Ovid databases were searched to identify original research studies that examined adult cognitive outcomes after childhood mTBI.

MAIN MEASURES

Cognitive outcome measures assessed memory, attention, visuospatial abilities, processing speed, comprehension, reasoning, intellectual functioning, and executive functioning. Outcome measures ranged from self-reported cognitive symptoms to objective testing.

RESULTS

A total of 4216 articles were screened, leading to the inclusion of 6 published studies for review (3 prospective cohort and 3 retrospective cohort), with 131 537 participants (mTBI = 6724; controls = 123 823). Review of the included articles suggests that adults with a history of childhood mTBI perform within the average range expected for adult cognitive functioning, although they may perform more poorly than non-head-injured comparison groups on a variety of cognitive measures. Injury-related factors, such as requiring electroencephalography within 24 hours of injury and posttraumatic amnesia lasting longer than 30 minutes, may be associated with variability in adult cognitive outcomes.

CONCLUSION

The weight of the available evidence suggests that childhood mTBI does not have a significant impact on adult cognitive functioning. However, further research is needed to provide a more comprehensive understanding of the long-term cognitive outcomes of childhood mTBI and to identify predictors of those outcomes in adulthood.

Traumatic Brain Injury in Children and Adolescents: Psychiatric Disorders 24 Years Later

OBJECTIVE

The investigators aimed to extend findings regarding predictive factors of psychiatric outcomes among children and adolescents with traumatic brain injury (TBI) from 2 to 24 years postinjury.

METHODS

Youths aged 6-14 years who were hospitalized following TBI from 1992 to 1994 were assessed at baseline for TBI severity and for preinjury psychiatric, adaptive, and behavioral functioning; family functioning; family psychiatric history; socioeconomic status; and intelligence within weeks of injury. Predictors of psychiatric outcomes following pediatric TBI at 3, 6, 12, and 24 months postinjury have previously been reported. In this study, repeat psychiatric assessments were completed at 24 years postinjury with the same cohort, now adults aged 29-39 years, with the outcome measure being presence of a psychiatric disorder not present before the TBI ("novel psychiatric disorder").

RESULTS

Fifty participants with pediatric TBI were initially enrolled, and the long-term outcome analyses focused on data from 45 individuals. Novel psychiatric disorder was present in 24 out of 45 (53%) participants. Presence of a current novel psychiatric disorder was independently predicted by the presence of a preinjury lifetime psychiatric disorder and by severity of TBI.

CONCLUSIONS

Long-term psychiatric outcome (mean=23.92 years [SD=2.17]) in children and adolescents hospitalized for TBI can be predicted at the point of the initial hospitalization encounter by the presence of a preinjury psychiatric disorder and by greater injury severity.

REPIMPACT - a prospective longitudinal multisite study on the effects of repetitive head impacts in youth soccer

Repetitive head impacts (RHI) are common in youth athletes participating in contact sports. RHI differ from concussions; they are considered hits to the head that usually do not result in acute symptoms and are therefore also referred to as “subconcussive” head impacts. RHI occur e.g., when heading the ball or during contact with another player. Evidence suggests that exposure to RHI may have cumulative effects on brain structure and function. However, little is known about brain alterations associated with RHI, or about the risk factors that may lead to clinical or behavioral sequelae. REPIMPACT is a prospective longitudinal study of competitive youth soccer players and non-contact sport controls aged 14 to 16 years. The study aims to characterize consequences of exposure to RHI with regard to behavior (i.e., cognition, and motor function), clinical sequelae (i.e., psychiatric and neurological symptoms), brain structure, function, diffusion and biochemistry, as well as blood- and saliva-derived measures of molecular processes associated with exposure to RHI (e.g., circulating microRNAs, neuroproteins and cytokines). Here we present the structure of the REPIMPACT Consortium which consists of six teams of clinicians and scientists in six countries. We further provide detailed information on the specific aims and the design of the REPIMPACT study. The manuscript also describes the progress made in the study thus far. Finally, we discuss important challenges and approaches taken to overcome these challenges.

Pediatric concussion working memory outcomes: a scoping review

Objective: Characterize the working memory (WM) profile of children and youth who have experienced concussion by systematically synthesizing existing literature on the neuropsychological outcomes of these injuries.Methods: Implemented a peer-reviewed search strategy combining key concepts of concussion/mild traumatic brain injury (mTBI), WM, and pediatrics across MedLine, Embase, PsycINFO, and CINAHL. Included studies written in English with extractable results on a WM outcome measure in individuals aged 21 and under who experienced concussion. Applied narrative synthesis to identify trends in the literature. Assessed risk of bias and quality using the NHLBI's Quality Assessment of Observational Cohort and Cross-Sectional Studies.Results: 40 articles met inclusion criteria. 34/40 studies compared WM performance in children or youth with concussion to healthy controls, pre-injury performance, or normative values, of which 15 reported significantly lower WM performance in the concussion sample. Visual/spatial WM was more consistently impacted than verbal WM. Cognitive demanding dual-task conditions were also reliably impacted.Conclusion: Literature indicated that WM is vulnerable to negative outcomes following pediatric concussion, yet the nature of outcomes is variable. Clinicians and researchers should implement comprehensive and theoretically motivated WM assessments to better understand the WM components impacted by injury.

Long-Term Psychiatric Outcomes in Adults with History of Pediatric Traumatic Brain Injury

The objective of the study was to compare psychiatric outcomes in adults with and without history of pediatric traumatic brain injury (TBI). Youth ages 6 to 14 years hospitalized for TBI from 1992 to 1994 were assessed at baseline and at 3, 6, 12, and 24 months post-injury. In the current study, psychiatric assessments were repeated at 24 years post-injury with the same cohort, now adults ages 29 to 39 years. A control group of healthy adults also was recruited for one-time cross-sectional assessments. Outcome measures included: 1) presence of a psychiatric disorder since the 24-month assessment not present before the TBI ("novel psychiatric disorder," NPD), or in the control group, the presence of a psychiatric disorder that developed after the mean age of injury of the TBI group plus 2 years; and 2) Time-to-Event for onset of an NPD during the same time periods. In the TBI group, NPDs were significantly more common, and presence of a current NPD was significantly predicted by presence of a pre-injury lifetime psychiatric disorder and by abnormal day-of-injury computed tomography (CT) scan. Compared with controls, the TBI group also had significantly shorter Time-to-Event for onset of any NPD. These findings demonstrate that long-term psychiatric outcomes in adults previously hospitalized for pediatric TBI are significantly worse when compared with adult controls without history of pediatric TBI, both in terms of prevalence and earlier onset of NPD. Further, in the TBI group, long-term NPD outcome is predicted independently by presence of pre-injury psychiatric disorder and abnormal day-of-injury CT scan.

Pediatric traumatic brain injury and abusive head trauma

Childhood traumatic brain injury (TBI) commonly occurs during brain development and can have direct, immediately observable neurologic, cognitive, and behavioral consequences. However, it can also disrupt subsequent brain development, and long-term outcomes are a combination of preinjury development and abilities, consequences of brain injury, as well as delayed impaired development of skills that were immature at the time of injury. There is a growing number of studies on mild TBI/sport-related concussions, describing initial symptoms and their evolution over time and providing guidelines for effective management of symptoms and return to activity/school/sports. Mild TBI usually does not lead to long-term cognitive or academic consequences, despite reports of behavioral/psychologic issues postinjury. Regarding moderate to severe TBI, injury to the brain is more severe, with evidence of a number of detrimental consequences in various domains. Patients can display neurologic impairments (e.g., motor deficits, signs of cerebellar disorder, posttraumatic epilepsy), medical problems (e.g., endocrine pituitary deficits, sleep-wake abnormalities), or sensory deficits (e.g., visual, olfactory deficits). The most commonly reported deficits are in the cognitive-behavioral field, which tend to be significantly disabling in the long-term, impacting the development of autonomy, socialization and academic achievement, participation, quality of life, and later, independence and ability to enter the workforce (e.g., intellectual deficits, slow processing speed, attention, memory, executive functions deficits, impulsivity, intolerance to frustration). A number of factors influence outcomes following pediatric TBI, including preinjury stage of development and abilities, brain injury severity, age at injury (with younger age at injury most often associated with worse outcomes), and a number of family/environment factors (e.g., parental education and occupation, family functioning, parenting style, warmth and responsiveness, access to rehabilitation and care). Interventions should identify and target these specific factors, given their major role in postinjury outcomes. Abusive head trauma (AHT) occurs in very young children (most often <6 months) and is a form of severe TBI, usually associated with delay before appropriate care is sought. Outcomes are systematically worse following AHT than following accidental TBI, even when controlling for age at injury and injury severity. Children with moderate to severe TBI and AHT usually require specific, coordinated, multidisciplinary, and long-term rehabilitation interventions and school adaptations, until transition to adult services. Interventions should be patient- and family-centered, focusing on specific goals, comprising education about TBI, and promoting optimal parenting, communication, and collaborative problem-solving.

A Novel Clinical Research Modality for Enrolling Diverse Participants Using a Diverse Team

The advancement of the pediatric traumatic brain injury (TBI) knowledge base requires biospecimens and data from large samples. This study seeks to describe a novel clinical research modality to establish best practices for enrolling a diverse pediatric TBI population and quantifying key information on enrollment into biobanks. Screening form responses were standardized and cleaned through Google Sheets. Data were used to analyze total individuals at each enrollment stage. R was utilized for final analysis, including logistic model and proportion statistical tests, to determine further significance and relationships. Issues throughout data cleaning shed light on limitations of the consent modality. The results suggest that through a diverse research team, the recruited sample exceeds traditional measures of representation (e.g., sex, race, ethnicity). Sex demographics of the study are representative of the local population. Screening for candidates is critical to the success of the consent modality. The consent modality may be modified to increase the diversity of the study population and accept bilingual candidates. Researchers must implement best practices, including increasing inclusivity of bilingual populations, utilizing technology, and improving participant follow-up, to improve health disparities for understudied clinical populations.

Revisits, readmissions, and outcomes for pediatric traumatic brain injury in California, 2005-2014

Long-term outcomes related to emergency department revisit, hospital readmission, and all-cause mortality, have not been well characterized across the spectrum of pediatric traumatic brain injury (TBI). We evaluated emergency department visit outcomes up to 1 year after pediatric TBI, in comparison to a referent group of trauma patients without TBI. We performed a longitudinal, retrospective study of all pediatric trauma patients who presented to emergency departments and hospitals in California from 2005 to 2014. We compared emergency department visits, dispositions, revisits, readmissions, and mortality in pediatric trauma patients with a TBI diagnosis to those without TBI (Other Trauma patients). We identified 208,222 pediatric patients with an index diagnosis of TBI and 1,314,064 patients with an index diagnosis of Other Trauma. Population growth adjusted TBI visits increased by 5.6% while those for Other Trauma decreased by 40.7%. The majority of patients were discharged from the emergency department on their first visit (93.2% for traumatic brain injury vs. 96.5% for Other Trauma). A greater proportion of TBI patients revisited the emergency department (33.4% vs. 3.0%) or were readmitted to the hospital (0.9% vs. 0.04%) at least once within a year of discharge. The health burden within a year after a pediatric TBI visit is considerable and is greater than that of non-TBI trauma. These data suggest that outpatient strategies to monitor for short-term and longer-term sequelae after pediatric TBI are needed to improve patient outcomes, lessen the burden on families, and more appropriately allocate resources in the healthcare system.

Structural abnormalities in thalamo-prefrontal tracks revealed by high angular resolution diffusion imaging predict working memory scores in concussed children

Because of their high prevalence, heterogeneous clinical presentation, and wide-ranging sequelae, concussions are a challenging neurological condition, especially in children. Shearing forces transmitted across the brain during concussions often result in white matter damage. The neuropathological impact of concussions has been discerned from animal studies and includes inflammation, demyelination, and axonal loss. These pathologies can overlap during the sub-acute stage of recovery. However, due to the challenges of accurately modeling complex white matter structure, these neuropathologies have not yet been differentiated in children in vivo. In the present study, we leveraged recent advances in diffusion imaging modeling, tractography, and tractometry to better understand the neuropathology underlying working memory problems in concussion. Studying a sample of 16 concussed and 46 healthy youths, we used novel tractography methods to isolate 11 working memory tracks. Along these tracks, we measured fractional anisotropy, diffusivities, track volume, apparent fiber density, and free water fraction. In three tracks connecting the right thalamus to the right dorsolateral prefrontal cortex (DLPFC), we found microstructural differences suggestive of myelin alterations. In another track connecting the left anterior-cingulate cortex with the left DLPFC, we found microstructural changes suggestive of axonal loss. Structural differences and tractography reconstructions were reproduced using test-retest analyses. White matter structure in the three thalamo-prefrontal tracks, but not the cingulo-prefrontal track, appeared to play a key role in working memory function. The present results improve understanding of working memory neuropathology in concussions, which constitutes an important step toward developing neuropathologically informed biomarkers of concussion in children.

Brain damage by trauma

Traumatic brain injury (TBI) represents a major clinical and economic challenge for health systems worldwide, and it is considered one of the leading causes of disability in young adults. The recent development of brain-computer interface (BCI) tools to target cognitive and motor impairments has led to the exploration of these techniques as potential therapeutic tools in patients with TBI. However, little evidence has been gathered so far to support applicability and efficacy of BCIs for TBI in a clinical setting. In the present chapter, results from studies using BCI approaches in conscious patients with TBI or in animal models of TBI as well as an overview of future directions in the use of BCIs to treat cognitive symptoms in this patient population will be presented.

Relative Head Impact Exposure and Brain White Matter Alterations After a Single Season of Competitive Football: A Pilot Comparison of Youth Versus High School Football

OBJECTIVE

Youth athletes are believed to be more susceptible to white matter (WM) degradation resulting from head impact exposure relative to high school (HS) athletes; this hypothesis has not been objectively tested. The purpose of this study was to determine preseason to postseason changes in WM integrity from repetitive head impacts for youth football (YFB) players compared with HS football players during a competitive football season.

DESIGN

Prospective cohort.

SETTING

One season of YFB (grades 7 and 8) and varsity HS football (grades 10-12).

PATIENTS OR OTHER PARTICIPANTS

Twelve YFB (13.08 ± 0.64 years) and 21 HS (17.5 ± 0.78 years) athletes.

INTERVENTIONS

Participants completed 2 magnetic resonance imaging sessions: preseason and postseason. Head impact exposure was recorded during practice and games using a helmet-mounted accelerometer.

MAIN OUTCOME MEASURES

Tract-based spatial statistics were used to evaluate group differences in preseason to postseason changes in diffusion tensor imaging, including fractional anisotropy and mean diffusivity (MD), axial diffusivity (AD), and radial diffusivity (RD).

RESULTS

The HS group exhibited significant preseason to postseason reductions in MD, AD, and RD (P < 0.05, corrected) in widespread WM areas. Significant WM reductions for the YFB group were only observed for AD (P < 0.05, corrected), but was more limited in extent compared with HS.

CONCLUSIONS

Significant preseason to postseason AD reduction was found in both YFB and HS groups after one season of competitive play. Our results did not confirm recent speculation that younger children are more susceptible to the deleterious effects of repetitive head impacts compared with their older counterparts.

MRI-based measures of intracortical myelin are sensitive to a history of TBI and are associated with functional connectivity

Traumatic brain injuries (TBIs) induce persistent behavioral and cognitive deficits via diffuse axonal injury. Axonal injuries are often examined in vivo using diffusion MRI, which identifies damaged and demyelinated regions in deep white matter. However, TBI patients can exhibit impairment in the absence of diffusion-measured abnormalities, suggesting that axonal injury and demyelination may occur outside the deep white matter. Importantly, myelinated axons are also present within the cortex. Cortical myelination cannot be measured using diffusion imaging, but can be mapped in-vivo using the T1-w/T2-w ratio method. Here, we conducted the first work examining effects of TBI on intracortical myelin in living humans by applying myelin mapping to 46 US Military Veterans with a history of TBI. We observed that myelin maps could be created in TBI patients that matched known distributions of cortical myelin. After controlling for age and presence of blast injury, the number of lifetime TBIs was associated with reductions in the T1-w/T2-w ratio across the cortex, most significantly in a highly-myelinated lateral occipital region corresponding with the human MT+ complex. Further, the T1-w/T2-w ratio in this MT+ region predicted resting-state functional connectivity of that region. By contrast, a history of blast TBI did not affect the T1-w/T2-w ratio in either a diffuse or focal pattern. These findings suggest that intracortical myelin, as measured using the T1-w/T2-w ratio, may be a TBI biomarker that is anatomically complementary to diffusion MRI. Thus, myelin mapping could potentially be combined with diffusion imaging to improve MRI-based diagnostic tools for TBI.

Greater neurodegeneration and behavioral deficits after single closed head traumatic brain injury in adolescent versus adult male mice

Traumatic brain injury (TBI) is a major public health concern affecting 2.8 million people per year in the United States, of whom about 1 million are children under 19 years old. Animal models of TBI have been developed and used in multiple ages of animals, but direct comparisons of adult and adolescent populations are rare. The current studies were undertaken to directly compare outcomes between adult and adolescent male mice, using a closed head, single-impact model of TBI. Six-week-old adolescent and 9-week-old adult male mice were subjected to mild-moderate TBI. Histological measures for neurodegeneration, gliosis, and microglial neuroinflammation, and behavioral tests of locomotion and memory were performed. Adolescent TBI mice have increased mortality (Χ²  = 20.72, p < 0.001) compared to adults. There is also evidence of hippocampal neurodegeneration in adolescents that is not present in adults. Hippocampal neurodegeneration correlates with histologic activation of microglia, but not with increased astrogliosis. Adults and adolescents have similar locomotion deficits after TBI that recover by 16 days postinjury. Adolescents have memory deficits as evidenced by impaired novel object recognition between 3-4 and 4-16 days postinjury (F_1,26  = 5.23, p = 0.031) while adults do not. In conclusion, adults and adolescents within a close age range (6-9 weeks) respond to TBI differently. Adolescents are more severely affected by mortality, neurodegeneration, and inflammation in the hippocampus compared to adults. Adolescents, but not adults, have worse memory performance after TBI that lasts at least 16 days postinjury.

Proactive inhibition deficits with normal perfusion after pediatric mild traumatic brain injury

Although much attention has been generated in popular media regarding the deleterious effects of pediatric mild traumatic brain injury (pmTBI), a paucity of empirical evidence exists regarding the natural course of biological recovery. Fifty pmTBI patients (12–18 years old) were consecutively recruited from Emergency Departments and seen approximately 1 week and 4 months post‐injury in this prospective cohort study. Data from 53 sex‐ and age‐matched healthy controls (HC) were also collected. Functional magnetic resonance imaging was obtained during proactive response inhibition and at rest, in conjunction with independent measures of resting cerebral blood flow. High temporal resolution imaging enabled separate modeling of neural responses for preparation and execution of proactive response inhibition. A priori predictions of failed inhibitory responses (i.e., hyperactivation) were observed in motor circuitry (pmTBI>HC) and sensory areas sub‐acutely and at 4 months post‐injury. Paradoxically, pmTBI demonstrated hypoactivation (HC>pmTBI) during target processing, along with decreased activation within prefrontal cognitive control areas. Functional connectivity within motor circuitry at rest suggested that deficits were limited to engagement during the inhibitory task, whereas normal resting cerebral perfusion ruled out deficits in basal perfusion. In conclusion, current results suggest blood oxygen‐level dependent deficits during inhibitory control may exceed commonly held beliefs about physiological recovery following pmTBI, potentially lasting up to 4 months post‐injury.

Objective sleep outcomes 20 years after traumatic brain injury in childhood

Purpose: To assess objective sleep outcomes and correlates in young adults with a history of childhood traumatic brain injury.Materials and methods: Participants included 45 young adults who sustained brain injury in childhood (mild = 12, moderate = 22, and severe = 11) and 13 typically developing control participants. Sleep was assessed with actigraphy and sleep diaries recorded over 14 consecutive days. Rates of good sleep (sleep efficiency ≥ 85%) and poor sleep (sleep efficiency < 85%) were also evaluated.Results: At 20-years postinjury, participants with traumatic brain injury and controls presented with similar outcomes across the objective sleep parameters (all p > 0.050) and rates of poor sleepers were also similar between these groups (p = 0.735): 67% and 77%, respectively. However, moderate and severe traumatic brain injury and female sex were associated with longer sleep duration.Conclusions: These findings provide preliminary insights into objective sleep outcome and associated factors in the very-long-term after childhood brain injuries. They also indicate the need to monitor sleep outcomes in young adults with and without traumatic brain injury.Implication for rehabilitationSustaining traumatic brain injury in childhood can impact on several functional domains including sleep.Sleep disturbances, particularly insomnia-related symptoms, are common in this population, with evidence of poor outcomes reported until adolescence postinjury, while outcomes beyond adolescence remain unexplored.In this first investigation of objective sleep outcomes in young adults with a history of childhood traumatic brain injury, we showed that insomnia-related symptoms are highly prevalent in both young adults with traumatic brain injury (67%) and healthy controls (77%).These findings suggest the need to routinely evaluate and treat sleep problem in young adults in general, irrespective of history of childhood traumatic brain injury.

A targeted neuropsychological examination of children with a history of sport-related concussion

Experimental research suggests that sport-related concussion can lead to persistent alterations in children's neurophysiology and cognition. However, the search for neuropsychological tests with a similar ability to detect long-term deficits continues.

PRIMARY OBJECTIVE

The current study assessed whether a target battery of neuropsychological measures of higher cognition and academic achievement would detect lingering deficits in children 2 years after injury.

RESEARCH DESIGN

Cross-sectional.

METHODS AND PROCEDURE

A total of 32 pre-adolescent children (16 concussion history, 16 control) completed a targeted battery of neuropsychological and academic tests.

MAIN OUTCOMES AND RESULTS

Children with a history of concussion exhibited selective deficits during the Raven's Coloured Progressive Matrices, Comprehensive Trail-Making Test, and the mathematics sub-section of the WRAT-3. Deficit magnitude was significantly related to age at injury, but not time since injury.

CONCLUSIONS

The current results suggest that neuropsychological measures of higher cognition and academic achievement may be sensitive to lingering deficits, and that children injured earlier in life may exhibit worse neuropsychological and academic performance.

Clinical utility of neuropsychological tests for employment outcomes in persons with cognitive impairment after moderate to severe traumatic brain injury

OBJECTIVE

To retrospectively examine the clinical utility of neuropsychological tests (NPTs) for predicting employment outcomes in persons with cognitive impairment after moderate to severe traumatic brain injury (TBI).

METHODS

132 individuals of working age with cognitive impairment after moderate to severe TBI were classified into three groups by employment status: competitive employment (CE); supported employment (SE); and unemployed (UE). NPT scores were compared among groups. Using multinomial logistic regression with group allocation as the dependent variable, significant variables were identified, and receiver operating characteristic (ROC) curves were calculated.

RESULTS

Comparison of NPT results among the three groups showed significant differences for all NPTs (all items, p < 0.01). Using multinomial logistic regression analysis, Rivermead Behavioral Memory Test (RBMT) and Behavioral Assessment of the Dysexecutive Syndrome from CE versus SE and Trail Making Test-B and RBMT from SE versus UE were identified. ROC curve analysis indicated small to moderate accuracy (area under the curve, 0.63-0.84).

CONCLUSION

NPT scores can predict future employment status in patients with cognitive impairment after TBI. These findings may lead to improved clinical assessments when providing work support. Future research should consider occupational categories, managerial categories, and types of re-employment.

Developmental trajectories of adaptive functioning following early mild traumatic brain injury

Adaptive behavior impairments have been reported in children with severe traumatic brain injury (TBI) but are not typically found following mild TBI. It is possible that mild TBI induces subtle changes in adaptive functioning that are not captured in conventional group comparisons. This study aimed to explore time course changes in adaptive functioning following early mild TBI. Parents of 63 children with mild TBI and 53 children with orthopedic injuries aged between 1.5 and 5 years at the time of injury completed the Adaptive Behavior Assessment System-II at three time points: retrospectively to assess pre-injury functioning, then at 6 and 18 months post-injury. Developmental trajectories of adaptive functioning domains (practical, conceptual, and social) reported by parents were modeled using linear mixed-model analyses. Findings suggest that mild TBI may disrupt the expected developmental progression of children's social adaptive behavior, but does not appear to alter practical and conceptual domains.

Advanced biomarkers of pediatric mild traumatic brain injury: Progress and perils

There is growing public concern about neurodegenerative changes (e.g., Chronic Traumatic Encephalopathy) that may occur chronically following clinically apparent and clinically silent (i.e., sub-concussive blows) pediatric mild traumatic brain injury (pmTBI). However, there are currently no biomarkers that clinicians can use to objectively diagnose patients or predict those who may struggle to recover. Non-invasive neuroimaging, electrophysiological and neuromodulation biomarkers have promise for providing evidence of the so-called "invisible wounds" of pmTBI. Our systematic review, however, belies that notion, identifying a relative paucity of high-quality, clinically impactful, diagnostic or prognostic biomarker studies in the sub-acute injury phase (36 studies on unique samples in 28 years), with the majority focusing on adolescent pmTBI. Ultimately, well-powered longitudinal studies with appropriate control groups, as well as standardized and clearly-defined inclusion criteria (time post-injury, injury severity and past history) are needed to truly understand the complex pathophysiology that is hypothesized (i.e., still needs to be determined) to exist during the acute and sub-acute stages of pmTBI and may underlie post-concussive symptoms.

Women in Prison With Traumatic Brain Injury: Prevalence, Mechanism, and Impact on Mental Health

Relatively little is known about the characteristics of female offenders. Here, we studied the prevalence of traumatic brain injury (TBI) and mental health issues in an exclusively female prison population in New Zealand. Participants ( N = 38) were recruited from all security levels at Christchurch Women's Prison. Measures for depression, anxiety, and stress, sleep, and a history of TBI were administered; 94.7% (36/38) of participants presented with a history of TBI. Younger age at first injury was associated with an increased risk of mental health problems. The study concludes that TBI is highly prevalent among female offenders and may be linked to increased mental health problems. TBI should be considered as an important factor in offender pathways and treatment programs.

Corpus Callosum Vasculature Predicts White Matter Microstructure Abnormalities after Pediatric Mild Traumatic Brain Injury

Emerging data suggest that pediatric traumatic brain injury (TBI) is associated with impaired developmental plasticity and poorer neuropsychological outcomes than adults with similar head injuries. Unlike adult mild TBI (mTBI), the effects of mTBI on white matter (WM) microstructure and vascular supply are not well understood in the pediatric population. The cerebral vasculature plays an important role providing necessary nutrients and removing waste. To address this critical element, we examined the microstructure of the corpus callosum (CC) following pediatric mTBI using diffusion tensor magnetic resonance imaging (DTI), and investigated myelin, oligodendrocytes, and vasculature of WM with immunohistochemistry (IHC). We hypothesized that pediatric mTBI leads to abnormal WM microstructure and impacts the vasculature within the CC, and that these alterations to WM vasculature contribute to the long-term altered microstructure. We induced in mice a closed-head injury (CHI) mTBI at post-natal day (P) 14; then at 4, 14, and 60 days post-injury (DPI) mice were sacrificed for analysis. We observed persistent changes in apparent diffusion coefficient (ADC) within the ipsilateral CC following mTBI, indicating microstructural changes, but surprisingly changes in myelin and oligodendrocyte densities were minimal. However, vascular features of the ipsilateral CC such as vessel density, length, and number of junctions were persistently altered following mTBI. Correlative analysis showed a strong inverse relationship between ADC and vessel density at 60 DPI, suggesting increased vessel density following mTBI may restrict WM diffusion characteristics. Our findings suggest that WM vasculature contributes to the long-term microstructural changes within the ipsilateral CC following mTBI.

Childhood Traumatic Brain Injury and the Associations With Risk Behavior in Adolescence and Young Adulthood: A Systematic Review

OBJECTIVE

To systematically review the evidence that childhood traumatic brain injury (TBI) is associated with risk behavior in adolescence and young adulthood. Risk behavior included one or more of the following: use of substances, including alcohol, tobacco, and illicit substances; involvement in criminal behavior; and behavioral issues with conduct.

METHODS

A literature search was conducted using these terms: child, pediatric, traumatic brain injury, head injury, adolescent, psychosocial, antisocial, conduct, substance use. Studies describing original research were included if they reported outcomes over the age of 13 years in participants who sustained a TBI between birth and age 13 years.

RESULTS

Six journal articles were reviewed based on 4 separate studies. Three articles indicated a relationship between childhood TBI and increased problematic substance use in adolescence and young adulthood. Three articles supported an association between childhood TBI and later externalizing behavior; however, 2 articles did not support this link.

CONCLUSION

More research is warranted to explore the association between childhood TBI and later risk behavior as the relationship is not currently understood. Future research should build on existing longitudinal research with continued use of medical records for identifying TBI and inclusion of a non-brain-related trauma group to control for general injury effects.

High-Fidelity Measures of Whole-Brain Functional Connectivity and White Matter Integrity Mediate Relationships between Traumatic Brain Injury and Post-Traumatic Stress Disorder Symptoms

Traumatic brain injury (TBI) disrupts brain communication and increases risk for post-traumatic stress disorder (PTSD). However, mechanisms by which TBI-related disruption of brain communication confers PTSD risk have not been successfully elucidated in humans. This may be in part because functional MRI (fMRI), the most common technique for measuring functional brain communication, is unreliable for characterizing individual patients. However, this unreliability can be overcome with sufficient within-individual data. Here, we examined whether relationships could be observed among TBI, structural and functional brain connectivity, and PTSD severity by collecting ∼3.5 hours of resting-state fMRI and diffusion tensor imaging (DTI) data in each of 26 United States military veterans. We observed that a TBI history was associated with decreased whole-brain resting-state functional connectivity (RSFC), while the number of lifetime TBIs was associated with reduced whole-brain fractional anisotropy (FA). Both RSFC and FA explained independent variance in PTSD severity, with RSFC mediating the TBI-PTSD relationship. Finally, we showed that large amounts of per-individual data produced highly reliable RSFC measures, and that relationships among TBI, RSFC/FA, and PTSD could not be observed with typical data quantities. These results demonstrate links among TBI, brain connectivity, and PTSD severity, and illustrate the need for precise characterization of individual patients using high-data fMRI scanning.

Preliminary validation study of the Sydney Post-Traumatic Amnesia Scale (SYPTAS) in children with traumatic brain injury aged 4 to 7 years

The aim of this study was to assess the validity (developmental, concurrent, and predictive) of the Sydney Post-Traumatic Amnesia Scale (SYPTAS) for assessment of post-traumatic amnesia (PTA) in 4 to 7 year old children with traumatic brain injury (TBI). The design of this study is a retrospective cohort study. The SYPTAS was administered to 35 children (26 boys) aged 4.0 to 7.8 years who were consecutively admitted to a children's hospital with mild (n = 26), moderate (n = 3), or severe (n = 7) TBI. Concurrent validity of the SYPTAS was assessed against the Glasgow Coma Scale Scores (GCS). Predictive validity of the SYPTAS for functional outcomes was evaluated against the King's Outcome Scale for Childhood Head Injury (KOSCHI) at discharge and outpatient follow-ups. The length of PTA, measured by the SYPTAS, was invariant of children's chronological age, confirming the scale's developmental validity. Longer PTA was associated with lower GCS, endorsing concurrent validity of PTA duration measured by the SYPTAS, as a clinical indicator of TBI severity. PTA duration measured by the SYPTAS was a significant predictor of functional outcomes on the KOSCHI at discharge and follow-ups. This study provides evidence that the SYPTAS has good developmental, concurrent and predictive validity for assessment of PTA in children aged 4 to 7 years. PTA duration assessed by the SYPTAS is a clinical indicator of TBI severity and can aid rehabilitation planning post TBI.

Neuropsychological outcome of children with traumatic brain injury and its association with late magnetic resonance imaging findings: A cohort study

OBJECTIVES

To evaluate neuropsychological outcome after traumatic brain injury (TBI) and its association with trauma severity and late magnetic resonance imaging (MRI) findings.

METHODS

Prospective cohort study of patients with TBI admitted to the paediatric intensive care unit over 5 years. Trauma severity was determined by Glasgow Coma Scale (GCS), neurological outcome by King's Outcome Scale for Childhood Head Injury (KOSCHI) and neuropsychological outcome by Wechsler Intelligence Scale for Children - Fourth Edition.

RESULTS

Twenty-five children (median age 6 years at trauma) were included. Patients were divided into Disability (DIS)(n = 10) and Good Recovery (GR)(n = 15) groups. Initial GCS score was not significantly different in both groups (median 6 vs. 10; p = 0.34). DIS group had lower values ​​of working memory index (WMI)(median 74 vs. 94; p = 0.004), perceptual reasoning index (PRI)(75 vs. 96; p = 0.03), verbal comprehension index (VCI)(65 vs. 84; p = 0.02), processing speed index (PSI)(74 vs. 97; p = 0.01) and full-scale intelligence quotient (FSIQ)(65 vs. 87; p = 0.008). In the GR group, 60% of patients had normal or minimally altered MRI versus 10% of patients in the DIS group (p = 0.018). Fractional anisotropy positively correlated with WMI(r = 0.65; p = 0.005), PRI(r = 0.52; p = 0.03) and FSIQ(r = 0.50; p = 0.04).

CONCLUSIONS

Neuropsychological impairment was observed in 40% of children who suffered a TBI and was associated with late MRI abnormalities.

Inflammatory cytokine-induced changes in neural network activity measured by waveform analysis of high-content calcium imaging in murine cortical neurons

During acute neuroinflammation, increased levels of cytokines within the brain may contribute to synaptic reorganization that results in long-term changes in network hyperexcitability. Indeed, inflammatory cytokines are implicated in synaptic dysfunction in epilepsy and in an array of degenerative and autoimmune diseases of the central nervous system. Current tools for studying the impact of inflammatory factors on neural networks are either insufficiently fast and sensitive or require complicated and costly experimental rigs. Calcium imaging offers a reasonable surrogate for direct measurement of neuronal network activity, but traditional imaging paradigms are confounded by cellular heterogeneity and cannot readily distinguish between glial and neuronal calcium transients. While the establishment of pure neuron cultures is possible, the removal of glial cells ignores physiologically relevant cell-cell interactions that may be critical for circuit level disruptions induced by inflammatory factors. To overcome these issues, we provide techniques and algorithms for image processing and waveform feature extraction using automated analysis of spontaneous and evoked calcium transients in primary murine cortical neuron cultures transduced with an adeno-associated viral vector driving the GCaMP6f reporter behind a synapsin promoter. Using this system, we provide evidence of network perturbations induced by the inflammatory cytokines TNFα, IL1β, and IFNγ.

Role of microglia in a mouse model of paediatric traumatic brain injury

The cognitive and behavioural deficits caused by traumatic brain injury (TBI) to the immature brain are more severe and persistent than TBI in the mature brain. Understanding this developmental sensitivity is critical as children under four years of age sustain TBI more frequently than any other age group. Microglia (MG), resident immune cells of the brain that mediate neuroinflammation, are activated following TBI in the immature brain. However, the type and temporal profile of this activation and the consequences of altering it are still largely unknown. In a mouse model of closed head weight drop paediatric brain trauma, we characterized i) the temporal course of total cortical neuroinflammation and the phenotype of ex vivo isolated CD11B-positive microglia/macrophage (MG/MΦ) using a battery of 32 markers, and ii) neuropathological outcome 1 and 5days post-injury. We also assessed the effects of targeting MG/MΦ activation directly, using minocycline a prototypical microglial activation antagonist, on these processes and outcome. TBI induced a moderate increase in both pro- and anti-inflammatory cytokines/chemokines in the ipsilateral hemisphere. Isolated cortical MG/MΦ expressed increased levels of markers of endogenous reparatory/regenerative and immunomodulatory phenotypes compared with shams. Blocking MG/MΦ activation with minocycline at the time of injury and 1 and 2days post-injury had only transient protective effects, reducing ventricular dilatation and cell death 1day post-injury but having no effect on injury severity at 5days. This study demonstrates that, unlike in adults, the role of MG/MΦ in injury mechanisms following TBI in the immature brain may not be negative. An improved understanding of MG/MΦ function in paediatric TBI could support translational efforts to design therapeutic interventions.

The relationship between neuropsychological performance and depression in patients with traumatic brain injury

Traumatic brain injury is a multi-faceted condition that affects individuals on physical, cognitive, and emotional levels. The study investigated the relationship between depression and neuropsychological performance in a group with traumatic brain injury. A retrospective review was conducted on 75 participants who completed neuropsychological assessments. Information on clinical characteristics, sociodemographic information, neuropsychological outcomes, and Beck Depression Inventory scores were included in the analysis. Results indicated that 36% of the participants reported experiencing severe symptoms of depression, 28% moderate symptoms of depression, and 36% mild/minimal symptoms of depression. Performance on the Rey Auditory Verbal Learning Test indicated inverse relationships with depression scores suggesting that traumatic brain injury patients with lower depression scores perform better on verbal memory tasks. Similarly, findings for the written and oral versions of the Symbol Digit Modalities Test reflected inverse correlations with depression scores, indicating that lower depression scores are correlated with increased processing speed and capacity. A significant positive association between the time taken to complete the Trail Making Test Trail A and Trail B and depression scores was found, suggesting that higher depression scores in this sample were related to slower performance speed and lower executive performance. When specific clinical and sociodemographic variables were included as covariates in a partial correlational analysis, neuropsychological performance indicators and depression scores remained significant for Symbol Digit Modalities Test (oral and written), the Rey Auditory Verbal Learning Test Retrieval and Recognition trials, and Trail Making Test (Trail B). This study indicates that in a traumatic brain injury cohort, depression levels are significantly associated with specific neuropsychological performance measures. The findings of this study have implications for psychosocial treatment planning after a traumatic brain injury and contribute to our understandings of the inter-relationship between cognition and emotion.

Strengthening the quality of longitudinal research into cognitive-communication recovery after traumatic brain injury: A systematic review

PURPOSE

(i) To systematically review longitudinal and prognostic studies relating to the trajectory of cognitive-communication recovery after TBI and (ii) to provide recommendations to strengthen future research.

METHOD

Thirteen health literature databases were accessed up until July 2014.

MAIN MEASURES

Articles were screened systematically against pre-determined inclusion and exclusion criteria. Quality reviews were performed on the selected articles using a modified Downs & Black Rating Scale. Two independent reviewers performed the reviews.

RESULT

Sixteen longitudinal and prognostic articles met the inclusion criteria. There was evidence of either maintenance or improvement of cognitive-communication skills during the first 3 years post-injury. However, the studies did not provide detailed recovery trajectories, by failing to evaluate numerous data points over time. No studies evaluated recovery beyond 3 years post-injury. Injury severity, lesion location, brain volume loss and conversation skills may predict specific cognitive-communication outcomes. There was high variability in study characteristics and measures.

CONCLUSION

There is currently scarce evidence regarding cognitive-communication recovery and prognosis. People with TBI may recover or maintain pre-morbid cognitive-communication skills during the early rehabilitation stage. Further research detailing the recovery trajectory with a view to evaluating predictive factors is strongly indicated. Guidelines for future research are provided.

Accuracy of Self-report as a Method of Screening for Lifetime Occurrence of Traumatic Brain Injury Events that Resulted in Hospitalization

BACKGROUND

Traumatic brain injury (TBI) occurs frequently during child and early adulthood, and is associated with negative outcomes including increased risk of drug abuse, mental health disorders and criminal offending. Identification of previous TBI for at-risk populations in clinical settings often relies on self-report, despite little information regarding self-report accuracy. This study examines the accuracy of adult self-report of hospitalized TBI events and the factors that enhance recall.

METHODS

The Christchurch Health and Development Study is a birth cohort of 1265 children born in Christchurch, New Zealand, in 1977. A history of TBI events was prospectively gathered at each follow-up (yearly intervals 0-16, 18, 21, 25 years) using parental/self-report, verified using hospital records.

RESULTS

At 25 years, 1003 cohort members were available, with 59/101 of all hospitalized TBI events being recalled. Recall varied depending on the age at injury and injury severity, with 10/11 of moderate/severe TBI being recalled. Logistic regression analysis indicated that a model using recorded loss of consciousness, age at injury, and injury severity, could accurately classify whether or not TBI would be reported in over 74% of cases.

CONCLUSIONS

This research demonstrates that, even when individuals are carefully cued, many instances of TBI will not recalled in adulthood despite the injury having required a period of hospitalization. Therefore, screening for TBI may require a combination of self-report and review of hospital files to ensure that all cases are identified. (JINS, 2016, 22, 717-723).

The accuracy of adult recall for early mild traumatic brain injury

BACKGROUND

Childhood mild traumatic brain injury (mTBI) has been associated with negative adult outcomes. Effective interventions require identification of the injury event. There is currently little information regarding the accuracy of adult recall of childhood mTBI.

METHOD

Prospectively collected information from a large birth cohort was used to examine adult recall accuracy at age 25 for 161 childhood mTBI events occurring before age 10.

RESULTS

At age 25 cohort members recalled 11 outpatient injuries and 16 inpatient injuries. Recall accuracy increased with age. Logistic regression analysis distinguished between respondents who reported and did not report a childhood mTBI event correctly classifying 84.5% of cases. Age at injury, injury severity and loss of consciousness (LoC) made a unique statistically significant contribution to the model.

CONCLUSIONS

Most childhood mTBI events are not recalled in adulthood. Age at injury, injury severity and LoC significantly increase likelihood of recall and should be used in measures that evaluate whether injury has occurred. Implications for rehabilitation Traumatic brain injury occurs frequently and often results in ongoing deficits in attention, concentration, executive function and later mental health problems. Identification of a history of traumatic brain injury is essential to ensure that appropriate rehabilitative input is provided. Rehabilitation professionals need to be aware that mental health problems may be secondary to a prior traumatic brain injury. It is important for rehabilitation professionals elicit an accurate history of traumatic brain injury to ensure that their treatment plans are tailored to the needs of this group.