Preseason Vestibular Ocular Motor Screening in Children and Adolescents.

OBJECTIVES: The primary purpose of this study was to examine vestibular/ocular motor screening (VOMS) test performance in a sample of healthy youth ice hockey players. A particular focus was to investigate the potential effects of age and pre-existing health conditions, including concussion history, attention-deficit/hyperactivity disorder (ADHD), learning disability (LD), headaches/migraines, and depression/anxiety on preseason baseline VOMS performance, including the near point of convergence (NPC) distance. DESIGN: Cross-sectional cohort. SETTING: Outpatient physiotherapy clinic. PARTICIPANTS: Three hundred eighty-seven male youth hockey players, with an average age of 11.9 years (SD = 2.2, range = 8-17), completed the VOMS and responded to self- or parent-reported demographic and medical history questionnaires during preseason baseline assessments. INDEPENDENT VARIABLES ASSESSED: Age, sex, and mental and physical health history including ADHD, headaches, depression, anxiety, migraine, and LD. OUTCOME MEASURE: Vestibular/ocular motor screening. RESULTS: The large majority of boys scored within normal limits on the VOMS, ie, they reported no symptom provocation of more than 2 points on any VOMS subset (89%) and had a normal NPC distance, ie, <5 cm (78%). The individual VOMS subtests had low abnormality rates, and demographic and pre-existing health conditions, such as age, headache or migraine history, previous neurodevelopmental conditions, or mental health problems, were not associated with clinically meaningful symptom provocation during the VOMS. CONCLUSIONS: There was a low rate of abnormal findings for the individual VOMS subtests, with the exception of NPC distance, among male youth hockey players during preseason assessment.

Study protocol of the Aerobic exercise and CogniTIVe functioning in women with breAsT cancEr (ACTIVATE) trial: a two-arm, two-centre randomized controlled trial.

BACKGROUND: Up to 75% of women diagnosed with breast cancer report chemotherapy-related cognitive changes (CRCC) during treatment, including decreased memory, attention, and processing speed. Though CRCC negatively impacts everyday functioning and reduces overall quality of life in women diagnosed with breast cancer, effective interventions to prevent and/or manage CRCC are elusive. Consequently, women seldom receive advice on how to prevent or manage CRCC. Aerobic exercise is associated with improved cognitive functioning in healthy older adults and adults with cognitive impairments. Accordingly, it holds promise as an intervention to prevent and/or manage CRCC. However, evidence from randomized controlled trials (RCTs) supporting a beneficial effect of aerobic exercise on CRCC is limited. The primary aim of the ACTIVATE trial is to evaluate the impact of supervised aerobic exercise on CRCC in women receiving chemotherapy for breast cancer. METHODS: The ACTIVATE trial is a two-arm, two-centre RCT. Women diagnosed with stage I-III breast cancer and awaiting neo-adjuvant or adjuvant chemotherapy are recruited from hospitals in Ottawa (Ontario) and Vancouver (British Columbia), Canada. Recruits are randomized to the intervention group (aerobic exercise during chemotherapy) or the wait-list control group (usual care during chemotherapy and aerobic exercise post-chemotherapy). The primary outcome is cognitive functioning as measured by a composite cognitive summary score (COGSUM) of several neuropsychological tests. Secondary outcomes are self-reported cognitive functioning, quality of life, and brain structure and functioning (measured by magnetic resonance imaging (MRI)/functional MRI and electroencephalography). Assessments take place pre-chemotherapy (pre-intervention), mid-way through chemotherapy (mid-intervention/mid-wait period), end of chemotherapy (post-intervention/post-wait period; primary endpoint), 16-weeks post-chemotherapy, and at 1-year post-baseline. DISCUSSION: Aerobic exercise is a promising intervention for preventing and/or managing CRCC and enhancing quality of life among women diagnosed with breast cancer. The ACTIVATE trial tests several novel hypotheses, including that aerobic exercise can prevent and/or mitigate CRCC and that this effect is mediated by the timing of intervention delivery (i.e., during versus post-chemotherapy). Findings may support prescribing exercise during (or post-) chemotherapy for breast cancer and elucidate the potential role of aerobic exercise as a management strategy for CRCC in women with early-stage breast cancer. TRIAL REGISTRATION: The trial was registered with the ClinicalTrials.gov database ( NCT03277898 ) on September 11, 2017.

Hub distribution of the brain functional networks of newborns prenatally exposed to maternal depression and SSRI antidepressants.

BACKGROUND: Prenatal maternal depression (PMD) and selective serotonin reuptake inhibitor (SSRI) antidepressants are associated with increased developmental risk in infants. Reports suggest that PMD is associated with hyperconnectivity of the insula and the amygdala, while SSRI exposure is associated with hyperconnectivity of the auditory network in the infant brain. However, associations between functional brain organization and PMD and/or SSRI exposure are not well understood. METHODS: We examined the relation between PMD or SSRI exposure and neonatal brain functional organization. Infants of control (n = 17), depressed SSRI-treated (n = 20) and depressed-only (HAM-D ≥ 8) (n = 16) women, underwent resting-state functional magnetic resonance imaging at postnatal Day 6. At 6 months, temperament was assessed using Infant Behavioral Questionnaire (IBQ). We applied GTA and partial least square regression (PLSR) to the resting-state time series to assess group differences in modularity, and connector and provincial hubs. RESULTS: Modularity was similar across all groups. The depressed-only group showed higher connector hub values in the left anterior cingulate, insula, and caudate as well as higher provincial hub values in the amygdala compared to the control group. The SSRI group showed higher provincial hub values in Heschl's gyrus relative to the depressed-only group. PLSR showed that newborns' hub values predicted 10% of the variability in infant temperament at 6 months, suggesting different developmental patterns between groups. CONCLUSIONS: Prenatal exposures to maternal depression and SSRIs have differential impacts on neonatal functional brain organization. Hub values at 6 days predict variance in temperament between infant groups at 6 months of age.

The Role of Physical Activity in Recovery From Concussion in Youth: A Neuroscience Perspective.

BACKGROUND AND PURPOSE: Concussion is a major public health concern and one of the least understood neurological injuries. Children and youth are disproportionally affected by concussion, and once injured, take longer to recover. Current guidelines recommend a period of physical and cognitive rest with a gradual progressive return to activity. Although there is limited high-quality evidence (eg, randomized controlled trials) on the benefit of physical activity and exercise after concussion, most studies report a positive impact of exercise in facilitating recovery after concussion. In this article we characterize the complex and dynamic changes in the brain following concussion by reviewing recent results from neuroimaging studies and to inform physical activity participation guidelines for the management of a younger population (eg, 14-25 years of age) after concussion. SUMMARY OF KEY POINTS: Novel imaging methods and tools are providing a picture of the changes in the structure and function of the brain following concussion. These emerging results will, in the future, assist in creating objective, evidence-based pathways for clinical decision-making. Until such time, physical therapists should be aware that current neuroimaging evidence supports participation in physical activity after an initial and brief period of rest, and consider how best to incorporate exercise into rehabilitation to enhance recovery following concussion. RECOMMENDATIONS FOR CLINICAL PRACTICE: It is important that physical therapists understand the neurobiological impact of concussion injury and recovery, and be informed of the scientific rationale for the recommendations and guidelines for engagement in physical activity.Video Abstract available for more insights from the authors (see Supplemental Digital Content 1, available at: http://links.lww.com/JNPT/A205).

Mu Suppression Is Sensitive to Observational Practice but Results in Different Patterns of Activation in Comparison with Physical Practice.

Research has shown the effectiveness of observational practice for motor learning, but there continues to be debate about the mechanisms underlying effectiveness. Although cortical processes can be moderated during observation, after both physical and observational practice, how these processes change with respect to behavioural measures of learning has not been studied. Here we compared short-term physical and observational practice during the acquisition and retention of a novel motor task to evaluate how each type of practice modulates EEG mu rhythm (8-13 Hz). Thirty healthy individuals were randomly assigned to one of three groups: (1) physical practice (PP), (2) observational practice (OP), and (3) no practice (NP) control. There were four testing stages: baseline EEG, practice, postpractice observation, and delayed retention. There was significant bilateral suppression of mu rhythm during PP but only left lateralized mu suppression during OP. In the postpractice observation phase, mu suppression was bilateral and larger after PP compared to that after OP. NP control showed no evidence of suppression and was significantly different to both the OP and PP groups. When comparing the three groups in retention, the groups did not differ with respect to tracing times, but the PP group showed fewer errors, especially in comparison to the NP group. Therefore, although the neurophysiological measures index changes in the OP group, which are similar but moderated in comparison to PP, changes in these processes are not manifest in observational practice outcomes when assessed in a delayed retention test.

Attention-deficit/hyperactivity disorder is associated with baseline child sport concussion assessment tool third edition scores in child hockey players.

OBJECTIVES: The objectives of this study were to report baseline, preseason data for the Child-SCAT3, stratified by attention deficit hyperactivity disorder (ADHD) status, and examine group differences in Child-SCAT3 performance between children with and without ADHD. DESIGN: Cross-sectional study. METHODS: Young male hockey players (n = 304), aged 8-12 years, were administered the Child-SCAT3 during pre-season. Child-SCAT3 measures included a 20-item symptom scale, a Standardised Assessment of Concussion Child Version (SAC-C), a modified Balance Error Scoring System (m-BESS), a tandem gait task, and a coordination test. RESULTS: Children with ADHD (n = 20) endorsed significantly more symptoms (d = 0.95) and greater symptom severity (d = 1.13) compared to children without ADHD. No statistically significant differences were found between groups on Child-SCAT3 measures of cognitive or physical functioning (e.g. balance and coordination). CONCLUSIONS: ADHD should be considered when interpreting Child-SCAT3 scores, especially symptom reporting, in the context of concussion assessment. Better understanding of symptom reporting in uninjured child athletes with ADHD can inform the clinical interpretation of symptoms at baseline and following an actual or suspected concussion. Normative data for the Child-SCAT3 that is not stratified by or otherwise accounts for ADHD status should be used with caution when appraising performance of children with ADHD.

The development of the Pediatric Motivation Scale for rehabilitation.

BACKGROUND: Clinicians recognize that client motivation is key to optimizing rehabilitation; however, they are limited in its assessment by a paucity of motivation measures. PURPOSE: This paper presents the preliminary psychometrics of the Pediatric Motivation Scale (PMOT) designed to measure motivation from a child's perspective. METHOD: Content validity of the PMOT was measured through expert feedback (n = 12), and field testing ocurred with 41 children, 21 in rehabilitation and 20 healthy. Pearson product-moment correlations were used to analyze subscale correlations, test-retest reliability, and convergent validity with the Pediatric Volitional Questionnaire (PVQ). Internal consistency was measured using Cronbach's alpha. FINDINGS: Preliminary psychometric evaluation indicates strong internal consistency for PMOT total (α = .96) and subscales (α = .79-.91). The PMOT and PVQ moderately correlated in the rehabilitation subsample (r = .71, p < .01); no correlation was found in the healthy subsample (p > .05). Test-retest reliability was excellent (r = .97). IMPLICATIONS: This study provides preliminary psychometric evidence of the PMOT for children undergoing rehabilitation. These pilot findings warrant ongoing scale development.

The effects of motivating interventions on rehabilitation outcomes in children and youth with acquired brain injuries: a systematic review.

PRIMARY OBJECTIVE: To systematically review the evidence of the effects of motivating rehabilitation interventions on outcomes in children with acquired brain injury (ABI). METHODS: A literature search of six databases was conducted to identify intervention studies published until July 2013. The American Academy for Cerebral Palsy and Developmental Medicine (AACPDM) systematic review methodology was used as a framework. Two reviewers independently extracted data and assessed level of evidence and quality of studies. RESULTS: Of 891 records initially retrieved, 166 were screened by abstract and 31 by full text; 10 studies comprised of five randomized controlled trials, two case series and three single subject research design studies met the inclusion criteria. Studies fell into three intervention categories: (1) token economy based interventions; (2) virtual reality (VR); and (3) memory and attention interventions. CONCLUSIONS: A paucity of evidence has examined the effects of rehabilitation interventions with a motivational component. Token economies can significantly enhance memory and response inhibition performance in children with ABI. VR systems are motivating, yet findings are limited by the lack of use and availability of psychometrically evaluated measures of motivation. Findings point to the need for further research to evaluate the effects of motivation-based interventions.

Individualized monitoring of longitudinal heading exposure in soccer.

There is growing concern that repetitive soccer headers may have negative long-term consequences on brain health. However, inconsistent and low-quality heading exposure measurements limit past investigations of this effect. Here we conducted a comprehensive heading exposure analysis across all players on a university women's soccer team for over two calendar years (36 unique athletes), quantifying both game and practice exposure during all in-season and off-season periods, with over ten thousand video-confirmed headers. Despite an average of approximately 2 headers per day, players' daily exposures ranged from 0 to 45 headers, accumulating to highly variable total exposure of 2-223 headers over each in-season/off-season period. Overall, practices and off-season periods accounted for 70% and 45% of headers, respectively. Impact sensor data showed that heading kinematics fell within a tight distribution, but sensors could not capture full heading exposure due to factors such as compliance. With first-of-its-kind complete heading exposure data, we recommend exposure assessments be made on an individual level and include practice/off-season collection in addition to games and competitive seasons. Commonly used group statistics do not capture highly variable exposures, and individualized complete heading exposure tracking needs to be incorporated in future study designs for confirming the potential brain injury risk associated with soccer heading.

Distinct Effects of Brain Activation Using tDCS and Observational Practice: Implications for Motor Rehabilitation.

Complex motor skills can be acquired while observing a model without physical practice. Transcranial direct-current stimulation (tDCS) applied to the primary motor cortex (M1) also facilitates motor learning. However, the effectiveness of observational practice for bimanual coordination skills is debated. We compared the behavioural and brain causal connectivity patterns following three interventions: primary motor cortex stimulation (M1-tDCS), action-observation (AO) and a combined group (AO+M1-tDCS) when acquiring a bimanual, two-ball juggling skill. Thirty healthy young adults with no juggling experience were randomly assigned to either video observation of a skilled juggler, anodal M1-tDCS or video observation combined with M1-tDCS. Thirty trials of juggling were performed and scored after the intervention. Resting-state EEG data were collected before and after the intervention. Information flow rate was applied to EEG source data to measure causal connectivity. The two observation groups were more accurate than the tDCS alone group. In the AO condition, there was strong information exchange from (L) parietal to (R) parietal regions, strong bidirectional information exchange between (R) parietal and (R) occipital regions and an extensive network of activity that was (L) lateralized. The M1-tDCS condition was characterized by bilateral long-range connections with the strongest information exchange from the (R) occipital region to the (R) temporal and (L) occipital regions. AO+M1-tDCS induced strong bidirectional information exchange in occipital and temporal regions in both hemispheres. Uniquely, it was the only condition that was characterized by information exchange between the (R) frontal and central regions. This study provides new results about the distinct network dynamics of stimulating the brain for skill acquisition, providing insights for motor rehabilitation.

Evidence for outcomes of motivational rehabilitation interventions for children and adolescents with cerebral palsy: an American Academy for Cerebral Palsy and Developmental Medicine systematic review.

This study reviewed evidence regarding the effect of motivational rehabilitation interventions on outcomes in children with cerebral palsy. Six databases were searched for literature published up to May 2012. Included studies measured the purported motivating effects of motor-based rehabilitation interventions and the measured impact on outcomes. The American Academy for Cerebral Palsy and Developmental Medicine (AACPDM) systematic review methodology was used as a framework. Eight studies evaluated outcomes of studies using virtual reality interventions and one in a functional therapy context. Conflicting evidence from three (level II and level III) studies exists about the impact of these motivating interventions on motor outcomes measured in body functions. No statistical evidence regarding activity and participation outcomes exists. A single level II study found no significant difference in participants' motivation between motivational and conventional interventions. This review revealed a paucity of research on the effects of motivational interventions. Weaknesses include a lack of consistency in the examination of motivational interventions, limited use of definitions or theories to ground the concept of motivation, and reliance on non-validated methodological tools. This body of evidence would be strengthened by the use and development of robust outcome measures of motivation.

Concussion: current concepts in diagnosis and management.

Current understanding of the term "concussion" is fraught with misconceptions regarding the extent and nature of brain injury. Despite increasing attention in popular media and within the context of sports, considerable gaps exist in our knowledge of the diagnosis, underlying brain pathology, recovery of function, and optimal interventions for concussion. In this special interest article, we discuss the definition and risk factors associated with concussion, summarize and highlight some of the most widely used assessment tools, and critique the evidence for current principles of concussion management. Our evaluation has identified opportunities for novel neuroimaging techniques to improve the understanding of the pathophysiology of concussion and to evaluate the changes in the recovering brain in response to rehabilitation. In summary, a clear definition of the underlying brain pathology, the potential long-term consequences, and the risk factors of injury and recovery will help guide future research aiming to minimize the impact of injury and develop innovative and successful therapeutic approaches aimed at ameliorating the functional impairments associated with concussion.

Blink-related EEG oscillations are neurophysiological indicators of subconcussive head impacts in female soccer players: a preliminary study.

Introduction: Repetitive subconcussive head impacts can lead to subtle neural changes and functional consequences on brain health. However, the objective assessment of these changes remains limited. Resting state blink-related oscillations (BROs), recently discovered neurological responses following spontaneous blinking, are explored in this study to evaluate changes in BRO responses in subconcussive head impacts. Methods: We collected 5-min resting-state electroencephalography (EEG) data from two cohorts of collegiate athletes who were engaged in contact sports (SC) or non-contact sports (HC). Video recordings of all on-field activities were conducted to determine the number of head impacts during games and practices in the SC group. Results: In both groups, we were able to detect a BRO response. Following one season of games and practice, we found a strong association between the number of head impacts sustained by the SC group and increases in delta and beta spectral power post-blink. There was also a significant difference between the two groups in the morphology of BRO responses, including decreased peak-to-peak amplitude of response over left parietal channels and differences in spectral power in delta and alpha frequency range post-blink. Discussion: Our preliminary results suggest that the BRO response may be a useful biomarker for detecting subtle neural changes resulting from repetitive head impacts. The clinical utility of this biomarker will need to be validated through further research with larger sample sizes, involving both male and female participants, using a longitudinal design.

Recognition of facial expressions of emotion in adults with Down syndrome.

Research on facial expressions in individuals with Down syndrome (DS) has been conducted using photographs. Our goal was to examine the effect of motion on perception of emotional expressions. Adults with DS, adults with typical development matched for chronological age (CA), and children with typical development matched for developmental age (DA) viewed photographs and video clips of facial expressions of: happy, sad, mad, and scared. The odds of accurate identification of facial expressions were 2.7 times greater for video clips compared with photographs. The odds of accurate identification of expressions of mad and scared were greater for video clips compared with photographs. The odds of accurate identification of expressions of mad and sad were greater for adults but did not differ between adults with DS and children. Adults with DS demonstrated the lowest accuracy for recognition of scared. These results support the importance of motion cues in evaluating the social skills of individuals with DS.

A matter of perspective: Distinct brain mechanisms for evaluating positive and negative social feedback about oneself and another person.

Social rejection is a common experience in the life of young adults. Electroencephalographic (EEG) such as N1, P1 and P3 amplitude has been linked to experiencing social rejection; it remains unclear, whether these components are also influenced by the perspective, e.g., feedback directed to oneself or another person. We used EEG to investigate brain mechanisms associated with social feedback, directed either to oneself or another person. Female students (N = 57) engaged in a Chatroom Interact Task (CIT) during EEG. In this task participants received feedback as to whether themselves or someone else was accepted or rejected as a video chat partner. Mood was measured with the Positive Affect Negative Affect Schedule (PANAS). Participants showed more negative mood after rejection compared to acceptance. Spatiotemporal EEG cluster analysis revealed significant differences in P1, N1 and P3 ERP components associated with Acceptance vs. Rejection. The late positive potential (LPP) component was larger when processing self vs. other-related social feedback. Higher empathy, neuroticism, and lower age were associated with smaller LPP amplitude differences between Self and Other conditions. In this study we identified distinct brain dynamics associated with encoding social feedback and whether the feedback was targeted toward the self or to others.

Head Impact Exposure and Biomechanics in University Varsity Women's Soccer.

Soccer is a unique sport where players purposefully and voluntarily use their unprotected heads to manipulate the direction of the ball. There are limited soccer head impact exposure data to further study brain injury risks. The objective of the current study was to combine validated mouthpiece sensors with comprehensive video analysis methods to characterize head impact exposure and biomechanics in university varsity women's soccer. Thirteen female soccer athletes were instrumented with mouthpiece sensors to record on-field head impacts during practices, scrimmages, and games. Multi-angle video was obtained and reviewed for all on-field activity to verify mouthpiece impacts and identify contact scenarios. We recorded 1307 video-identified intentional heading impacts and 1011 video-verified sensor impacts. On average, athletes experienced 1.83 impacts per athlete-exposure, with higher exposure in practices than games/scrimmages. Median and 95th percentile peak linear and peak angular accelerations were 10.0, 22.2 g, and 765, 2296 rad/s2, respectively. Long kicks, top of the head impacts and jumping headers resulted in the highest impact kinematics. Our results demonstrate the importance of investigating and monitoring head impact exposure during soccer practices, as well as the opportunity to limit high-kinematics impact exposure through heading technique training and reducing certain contact scenarios.

Deep Learning Recurrent Neural Network for Concussion Classification in Adolescents Using Raw Electroencephalography Signals: Toward a Minimal Number of Sensors.

Artificial neural networks (ANNs) are showing increasing promise as decision support tools in medicine and particularly in neuroscience and neuroimaging. Recently, there has been increasing work on using neural networks to classify individuals with concussion using electroencephalography (EEG) data. However, to date the need for research grade equipment has limited the applications to clinical environments. We recently developed a deep learning long short-term memory (LSTM) based recurrent neural network to classify concussion using raw, resting state data using 64 EEG channels and achieved high accuracy in classifying concussion. Here, we report on our efforts to develop a clinically practical system using a minimal subset of EEG sensors. EEG data from 23 athletes who had suffered a sport-related concussion and 35 non-concussed, control athletes were used for this study. We tested and ranked each of the original 64 channels based on its contribution toward the concussion classification performed by the original LSTM network. The top scoring channels were used to train and test a network with the same architecture as the previously trained network. We found that with only six of the top scoring channels the classifier identified concussions with an accuracy of 94%. These results show that it is possible to classify concussion using raw, resting state data from a small number of EEG sensors, constituting a first step toward developing portable, easy to use EEG systems that can be used in a clinical setting.

Longitudinal changes in brain parenchyma due to mild traumatic brain injury during the first year after injury.

Chronic gray matter (GM) atrophy is a known consequence of moderate and severe traumatic brain injuries but has not been consistently shown in mild traumatic brain injury (mTBI). The aim of this study was to investigate the longitudinal effect of uncomplicated mTBI on the brain's GM and white matter (WM) from 6 weeks to 12 months after injury. Voxel-based-morphometry (VBM) was computed with the T1-weighted images of 48 uncomplicated mTBI patients and 37 orthopedic controls. Over the period from 6 weeks to 12 months, only patients who experienced uncomplicated mTBI, but not control participants, showed significant GM decrease predominantly in the right hemisphere along the GM-CSF border in lateral and medial portions of the sensorimotor cortex extending into the rolandic operculum, middle frontal gyrus, insula, and temporal pole. Additionally, only mTBI patients, but not controls, experienced significant WM decrease predominantly in the right hemisphere in the superior fasciculus longitudinalis, arcuate fasciculus, and cortical-pontine tracts as well as a significant WM increase in left arcuate fasciculus and left capsula extrema. We did not observe any significant change in the controls for the same time interval or any significant group differences in GM and WM probability at each of the two timepoints. This suggests that the changes along the brain tissue borders observed in the mTBI group represent a reorganization associated with subtle microscopical changes in intracortical myelin and not a direct degenerative process as a result of mTBI.

Recurrent neural network-based acute concussion classifier using raw resting state EEG data.

Concussion is a global health concern. Despite its high prevalence, a sound understanding of the mechanisms underlying this type of diffuse brain injury remains elusive. It is, however, well established that concussions cause significant functional deficits; that children and youths are disproportionately affected and have longer recovery time than adults; and that individuals suffering from a concussion are more prone to experience additional concussions, with each successive injury increasing the risk of long term neurological and mental health complications. Currently, the most significant challenge in concussion management is the lack of objective, clinically- accepted, brain-based approaches for determining whether an athlete has suffered a concussion. Here, we report on our efforts to address this challenge. Specifically, we introduce a deep learning long short-term memory (LSTM)-based recurrent neural network that is able to distinguish between non-concussed and acute post-concussed adolescent athletes using only short (i.e. 90 s long) samples of resting state EEG data as input. The athletes were neither required to perform a specific task nor expected to respond to a stimulus during data collection. The acquired EEG data were neither filtered, cleaned of artefacts, nor subjected to explicit feature extraction. The LSTM network was trained and validated using data from 27 male, adolescent athletes with sports related concussion, benchmarked against 35 non-concussed adolescent athletes. During rigorous testing, the classifier consistently identified concussions with an accuracy of > 90% and achieved an ensemble median Area Under the Receiver Operating Characteristic Curve (ROC/AUC) equal to 0.971. This is the first instance of a high-performing classifier that relies only on easy-to-acquire resting state, raw EEG data. Our concussion classifier represents a promising first step towards the development of an easy-to-use, objective, brain-based, automatic classification of concussion at an individual level.

Myelin water fraction decrease in individuals with chronic mild traumatic brain injury and persistent symptoms.

The diffuse and continually evolving secondary changes after mild traumatic brain injury (mTBI) make it challenging to assess alterations in brain-behaviour relationships. In this study we used myelin water imaging to evaluate changes in myelin water fraction (MWF) in individuals with chronic mTBI and persistent symptoms and measured their cognitive status using the NIH Toolbox Cognitive Battery. Fifteen adults with mTBI with persistent symptoms and twelve age, gender and education matched healthy controls took part in this study. We found a significant decrease in global white matter MWF in patients compared to the healthy controls. Significantly lower MWF was evident in most white matter region of interest (ROIs) examined including the corpus callosum (separated into genu, body and splenium), minor forceps, right anterior thalamic radiation, left inferior longitudinal fasciculus; and right and left superior longitudinal fasciculus and corticospinal tract. Although patients showed lower cognitive functioning, no significant correlations were found between MWF and cognitive measures. These results suggest that individuals with chronic mTBI who have persistent symptoms have reduced MWF.