Traumatic brain injury history and baseline symptoms outweigh sex differences for risk of concussion in a sample of collegiate athletes.

OBJECTIVE: To test the hypothesis that a history of traumatic brain injury (TBI) prior to the collegiate pre-season is associated with risk for re-injury. We also investigate sex differences, cognitive functioning, and self-reported concussion symptoms and their associations with concussion risk. METHODS: A longitudinal cohort study consisting of collegiate athletes (n = 212) who completed consecutive preseason evaluations (P1 and P2) between 2012 and 2015, averaging 12.9 (SD = 4.2) months apart. RESULTS: There were 40 new concussions recorded between P1 and P2, 21 (53%) of which were among athletes who reported a lifetime history of mild TBI/concussion at P1. New P1-P2 concussions occurred in 24% of female athletes (n = 23) and 15% of male athletes (n = 17). History of TBI and female sex were significant predictors of new concussion between P1 and P2; however, in adjusted models, the inclusion of Impulse Control and PCSS Total symptom scores attenuated the effect of sex on the risk for new injury. CONCLUSION: Collegiate athletes with a lifetime history of TBI had a significantly higher risk of sustaining a subsequent concussion. Pre-season emotional and somatic symptomology may contribute to incident concussion risk. The findings highlight the importance of considering lifetime head injury exposure and baseline symptomatology when interpreting sex differences and evaluating concussion risk.

Postintensive Care Syndrome in Survivors of Critical Illness Related to Coronavirus Disease 2019: Cohort Study From a New York City Critical Care Recovery Clinic.

OBJECTIVE: Determine the characteristics of postintensive care syndrome in the cognitive, physical, and psychiatric domains in coronavirus disease 2019 ICU survivors. DESIGN: Single-center descriptive cohort study from April 21, to July 7, 2020. SETTING: Critical care recovery clinic at The Mount Sinai Hospital in New York City. PATIENTS: Adults who had critical illness due to coronavirus disease 2019 requiring an ICU stay of 7 days or more and who agreed to a telehealth follow-up in the critical care recovery clinic 1-month post hospital discharge. INTERVENTIONS: None. MEASURES AND MAIN RESULTS: Patient-reported outcome measures assessing physical and psychiatric domains were collected electronically, a cognitive test was performed by a clinician, and clinical data were obtained through electronic medical records. Outcome measures assessed postintensive care syndrome symptoms in the physical (Modified Rankin Scale, Dalhousie Clinical Frailty Scale, Neuro-Quality of Life Upper Extremity and Lower Extremity Function, Neuro-Quality of Life Fatigue), psychiatric (Insomnia Severity Scale; Patient Health Questionnaire-9; and Posttraumatic Stress Disorder Checklist for Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition), and cognitive (Telephone Montreal Cognitive Assessment) domains. The 3-Level Version of Euro-QoL-5D was used to assess the physical and psychiatric domains. A diagnosis of postintensive care syndrome was made in cases with evidence of impairment in at least one postintensive care syndrome domain. We included 45 patients with a mean (sd) age of 54 (13) years, and 73% were male. Ninety-one percent of coronavirus disease 2019 ICU survivors fit diagnostic criteria for postintensive care syndrome. 86.7 % had impairments in the physical domain, 22 (48%) reported impairments in the psychiatric domain, and four (8%) had impairments on cognitive screening. We found that 58% had some degree of mobility impairment. In the psychiatric domain, 38% exhibited at least mild depression, and 18 % moderate to severe depression. Eighteen percent presented Posttraumatic Stress Disorder Checklist for Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition, scores suggestive of posttraumatic stress syndrome diagnosis. In the Telephone Montreal Cognitive Assessment, 9% had impaired cognition. CONCLUSIONS: Survivors of critical illness related to coronavirus disease 2019 are at high risk of developing postintensive care syndrome. These findings highlight the importance of planning for appropriate post-ICU care to diagnose and treat this population.

The Relationship Between Traumatic Brain Injury and Criminality in Juvenile Offenders.

OBJECTIVE: To examine the relationship between traumatic brain injury (TBI) and criminal behavior in youth who are incarcerated or on probation in Texas. SETTING: Seven juvenile justice facilities. PARTICIPANTS: Juvenile offenders in state or county correctional facilities or on probation. DESIGN: Screening for TBI was conducted among adolescents at 7 juvenile justice centers. MAIN MEASURES: Participants were administered the Brain Injury Screening Questionnaire, and results were linked to participants' offense history and psychiatric diagnoses. RESULTS: One in 4 juvenile offenders met criteria for TBI, and the majority of injuries occurred prior to the adolescents' criminal offenses. A history of TBI was related to more violent crimes, as well as more mental health diagnoses and symptoms. CONCLUSION: The high rates of TBI and levels of distress found in juvenile offenders suggest a need for preventive actions, interventions to compensate for challenges related to TBI, and programs to assist individuals' transitions into the community.

Screening for traumatic brain injury: findings and public health implications.

OBJECTIVE: To provide an overview of a series of projects that used a structured self-report screening tool in diverse settings and samples to screen for lifetime history of traumatic brain injury (TBI). SETTING: Diverse community settings. PARTICIPANTS: Homeless persons (n = 111), individuals with HIV seeking vocational rehabilitation (n = 173), youth in the juvenile justice system (n = 271), public schoolchildren (n = 174), substance users (n = 845), intercollegiate athletes (n = 90), and other community-based samples (n = 396). DESIGN: Cross-sectional. MAIN MEASURE: Brain Injury Screening Questionnaire. RESULTS: Screening using the Brain Injury Screening Questionnaire finds that 27% to 54% of those in high-risk populations report a history of TBI with chronic symptoms. Associations between TBI and social, academic, or other problems are evident in several studies. In non-high-risk community samples, 9% to 12% of individuals report TBI with chronic symptoms. CONCLUSION: Systematic TBI screening can be implemented efficiently and inexpensively in a variety of settings. Lifetime TBI history data gathered using a structured self-report instrument can augment existing estimates of the prevalence of TBI, both as an acute event and as a chronic condition. Identification of individuals with TBI can facilitate primary prevention efforts, such as reducing risk for reinjury in high-risk groups, and provide access to appropriate interventions that can reduce the personal and societal costs of TBI (tertiary prevention).

Visuomotor Synchronization: Military Normative Performance.

INTRODUCTION: Cognitive processes such as perception and reasoning are preceded and dependent on attention. Because of the close overlap between neural circuits of attention and eye movement, attention may be objectively quantified with recording of eye movements during an attention-dependent task. Our previous work demonstrated that performance scores on a circular visual tracking task that requires dynamic synchronization of the gaze with the target motion can be impacted by concussion, sleep deprivation, and attention deficit/hyperactivity disorder. The current study examined the characteristics of performance on a standardized predictive visual tracking task in a large sample from a U.S. Military population to provide military normative data. MATERIALS AND METHODS: The sample consisted of 1,594 active duty military service members of either sex aged 18-29 years old who were stationed at Fort Hood Army Base. The protocol was reviewed and approved by the U.S. Army Medical Research and Materiel Command Institutional Review Board. Demographic, medical, and military history data were collected using questionnaires, and performance-based data were collected using a circular visual tracking test and Trail Making Test. Differences in visual tracking performance by demographic characteristics were examined with a multivariate analysis of variance, as well as a Kolmogorov-Smirnov test and a rank-sum test. Associations with other measures were examined with a rank-sum test or Spearman correlations. RESULTS: Robust sex differences in visual tracking performance were found across the various statistical models, as well as age differences in several isolated comparisons. Accordingly, norms of performance scores, described in terms of percentile standings, were developed adjusting for age and sex. The effects of other measures on visual tracking performance were small or statistically non-significant. An examination of the score distributions of various metrics suggested that strategies preferred by men and women may optimize different aspects of visual tracking performance. CONCLUSION: This large-scale quantification of attention, using dynamic visuomotor synchronization performance, provides rigorously characterized age- and sex-based military population norms. This study establishes analytics for assessing normal and impaired attention and detecting changes within individuals over time. Practical applications for combat readiness and surveillance of attention impairment from sleep insufficiency, concussion, medication, or attention disorders will be enhanced with portable, easily accessible, fast, and reliable dynamic eye-tracking technologies.

Dual statistical models link baseline visual attention measure to risk for significant symptomatic concussion in sports.

Aim: Athletic pre-season testing can establish functional baseline for comparison following concussion. Whether impacts of future concussions may be foretold by such testing is little known. Materials & methods: Two sets of models for a significant burden of concussion were generated: a traditional approach using a series of logistic regressions, and a penalized regression approach using elastic net. Results: 3091 youth and adult athletes were baseline-assessed. 90 subsequently experienced concussion and 35 were still experiencing a significant burden of concussion when tested within two weeks. Both models associated prior history of head injury and visual attention-related metrics with a significant burden of concussion. Conclusion: Pre-season testing of visual attention may identify athletes who are at risk for significant sports-related concussion.

Athletic pre-season testing can establish functional baseline for comparison following concussion and may predict impacts of future concussions. In this study, 3,091 youth and adult athletes were baseline-assessed. 90 subsequently experienced concussion and 35 were still experiencing a significant burden of concussion when tested within two weeks. A statistical model and a machine-learning model both associated prior history of head injury and visual attention-related metrics with a significant burden of concussion. Pre-season testing of visual attention may identify athletes who are at risk for significant sports-related concussion.

Screening for Brain Injury Sustained in the Context of Intimate Partner Violence (IPV): Measure Development and Preliminary Utility of the Brain Injury Screening Questionnaire IPV Module.

Abstract Intimate partner violence (IPV) is associated with risk for multi-etiology brain injury (BI), including repetitive head impacts, isolated traumatic brain injuries (TBI), and anoxic/hypoxic injury secondary to nonfatal strangulation (NFS). IPV-related injuries are often unreported, but evidence suggests that survivors are more likely to report when asked directly. There are currently no validated tools for screening of brain injury related to IPV that meet World Health Organization guidelines for this population. Here, we describe measure development methods and preliminary utility of the Brain Injury Screening Questionnaire IPV (BISQ-IPV) module. We culled items from existing IPV and TBI screening tools and sought two rounds of stakeholder feedback regarding content coverage, terminology, and safety of administration. The resulting stakeholder-informed BISQ-IPV module is a seven-item self-report measure that uses contextual cues (e.g., being shoved, shaken, strangled) to query lifetime history of IPV-related head/neck injury. We introduced the BISQ-IPV module into the Late Effects of TBI (LETBI) study to investigate rates of violent and IPV-specific head/neck injury reporting in a TBI sample. Among those who completed the BISQ-IPV module (n = 142), 8% of the sample (and 20% of women) reported IPV-related TBI, and 15% of the sample (34% of women) reported IPV-related head or neck injury events that did not result in loss or alteration of consciousness. No men reported NFS; one woman reported inferred BI secondary to NFS, and 6% of women reported NFS events. Those who endorsed IPV-BI were all women, many were highly educated, and many reported low incomes. We then compared reporting of violent TBIs and head/neck injury events among individuals who completed the core BISQ wherein IPV is not specifically queried (administered from 2015-2018; n = 156) to that of individuals who completed the core BISQ preceded by the BISQ-IPV module (BISQ+IPV, administered from 2019-2021; n = 142). We found that 9% of those who completed the core BISQ reported violent TBI (e.g., abuse, assault), whereas 19% of those who completed the BISQ+IPV immediately preceding the core BISQ reported non-IPV-related violent TBI on the core BISQ. These findings suggest that standard TBI screening tools are inadequate for identifying IPV-BI and structured cueing of IPV-related contexts yields greater reporting of both IPV- and non-IPV-related violent BI. When not queried directly, IPV-BI remains a hidden variable in TBI research studies.

Insomnia, fatigue, and sleepiness in the first 2 years after traumatic brain injury: an NIDRR TBI model system module study.

OBJECTIVE: To determine the prevalence of insomnia and posttraumatic brain injury (TBI) fatigue (PTBIF) in individuals with moderate to severe TBI, to explore the relationship between PTBIF and insomnia and their association with outcomes. DESIGN: Cross-sectional study. SETTING: Five National Institute of Disability and Rehabilitation Research TBI Model Systems. PARTICIPANTS: Three hundred thirty-four individuals with TBI who completed 1-year (n = 213) or 2-year (n = 121) follow-up interviews between 2008 and 2012. MAIN OUTCOME RESULTS: Insomnia occurred in 11% to 24% and PTBIF in 33% to 44% of the individuals. Insomnia and fatigue were both related to sleep disturbance, sleep hygiene, satisfaction with life, anxiety, and depression. PTBIF was associated with greater disability and sleepiness. Insomnia without fatigue was rare (2%-3%) but PTBIF without insomnia occurred in 21% to 23% of the individuals. Comorbidity occurred in 9% to 22% of the individuals. CONCLUSIONS: Although PTBIF and insomnia are closely related and both associated with poorer quality of life, they are affected independently by a variety of factors, especially psychopathology and sleep quality. A majority of individuals with PTBIF do not have insomnia; and PTBIF appears to be related to disability severity and daytime sleepiness, where insomnia is not. Demographic and injury variables are not strong predictors of insomnia or PTBIF.

Evaluating the clinical benefit of brain-computer interfaces for control of a personal computer.

Brain-computer interfaces (BCIs) enabling the control of a personal computer could provide myriad benefits to individuals with disabilities including paralysis. However, to realize this potential, these BCIs must gain regulatory approval and be made clinically available beyond research participation. Therefore, a transition from engineering-oriented to clinically oriented outcome measures will be required in the evaluation of BCIs. This review examined how to assess the clinical benefit of BCIs for the control of a personal computer. We report that: (a) a variety of different patient-reported outcome measures can be used to evaluate improvements inhow a patient feels, and we offer some considerations that should guide instrument selection. (b) Activities of daily living can be assessed to demonstrate improvements inhow a patient functions, however, new instruments that are sensitive to increases in functional independence via the ability to perform digital tasks may be needed. (c) Benefits tohow a patient surviveshas not previously been evaluated but establishing patient-initiated communication channels using BCIs might facilitate quantifiable improvements in health outcomes.

International Survey of Antiseizure Medication Use in Patients with Complicated Mild Traumatic Brain Injury: A New York Neurotrauma Consortium Study.

BACKGROUND: Seizures and epilepsy after traumatic brain injury (TBI) negatively affect quality of life and longevity. Antiseizure medication (ASM) prophylaxis after severe TBI is associated with improved outcomes; these medications are rarely used in mild TBI. However, a paucity of research is available to inform ASM use in complicated mild TBI (cmTBI) and no empirically based clinical care guidelines for ASM use in cmTBI exist. We aim to identify seizure prevention and management strategies used by clinicians experienced in treating patients with cmTBI to characterize standard care and inform a systematic approach to clinical decision making regarding ASM prophylaxis. METHODS: We recruited a multidisciplinary international cohort through professional organizational listservs and social media platforms. Our questionnaire assessed factors influencing ASM prophylaxis after cmTBI at the individual, institutional, and health system-wide levels. RESULTS: Ninety-two providers with experience managing cmTBI completed the survey. We found a striking diversity of ASM use in cmTBI, with 30% of respondents reporting no/infrequent use and 42% reporting frequent use; these tendencies did not differ by provider or institutional characteristics. Certain conditions universally increased or decreased the likelihood of ASM use and represent consensus. Based on survey results, ASMs are commonly used in patients with cmTBI who experience acute secondary seizure or select positive neuroimaging findings; we advise caution in elderly patients and those with concomitant neuropsychiatric illness. CONCLUSIONS: This study is the first to characterize factors influencing clinical decision making in ASM prophylaxis after cmTBI based on multidisciplinary multicenter provider practices. Prospective controlled studies are necessary to inform standardized guideline development.

Does gender influence cognitive outcome after traumatic brain injury?

The aim of this study was to determine whether males and females differ in post-acute cognitive outcome following traumatic brain injury (TBI). Performances of 83 men and 75 women with mild to severe TBI were compared on measures of cognitive functions typically impacted by TBI (i.e., processing speed, executive functioning, and memory). Participants completed selected subtests of the Cambridge Neuropsychological Test Automated Battery (CANTAB). Among the participants with mild TBI, women scored significantly higher than men on a test of visual memory. There were no other significant gender differences in cognitive outcomes. These findings overall suggest that cognitive outcome after TBI does not differ according to gender, with the possible exception of memory functioning. Further research is needed to replicate this finding and determine which moderating variables may impact on the relationship between gender and cognitive outcome after TBI.

Anxiety disorders in adults treated by hemodialysis: a single-center study.

BACKGROUND: Anxiety is a complicating comorbid diagnosis in many patients with medical illnesses. In patients with end-stage renal disease (ESRD), anxiety disorders often are perceived to represent symptoms of depression rather than independent conditions and therefore have been relatively understudied in this medical population. STUDY DESIGN: To evaluate the psychosocial impact of anxiety disorders on patients with ESRD, we sought to identify the rates of these disorders in a sample of patients receiving hemodialysis at a single center by using a structured clinical interview. We also compared a commonly used screening measure, the Hospital Anxiety and Depression Scale (HADS), with these clinical diagnoses to determine the measure's criterion validity or ability to predict a psychiatric diagnosis in ESRD populations. Finally, we examined the relationship between anxiety diagnosis and perceptions of quality of life (QOL) and health status. SETTING & PARTICIPANTS: A sample of 70 randomly selected hemodialysis patients from an urban metropolitan center. PREDICTOR: Structured Clinical Interview for Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV) Axis I Diagnosis (SCID-I). OUTCOMES: HADS and Kidney Disease Quality of Life Short Form. RESULTS: Using the SCID, 71% of the sample received a DSM-IV Axis I diagnosis, with 45.7% of subjects meeting criteria for an anxiety disorder and 40% meeting criteria for a mood disorder. The concordance between DSM-IV anxiety disorders and anxiety scores acquired by using the HADS was not significant. Thus, although the HADS may provide an acceptable measure of overall "psychic distress" compared against the SCID-I, it has poor predictive power for anxiety diagnoses in patients with ESRD. Additionally, the presence of an anxiety disorder was associated with an overall perceived lower QOL (t = 2.4; P < 0.05). LIMITATIONS: Single-center study and a population not representative of US demographics. CONCLUSIONS: A substantial proportion of participating patients met criteria for an anxiety disorder. The utility of the HADS as a screening tool for anxiety in patients with ESRD should be questioned. The finding that anxiety disorders negatively impact on QOL and are not merely manifestations of depression in patients with ESRD emphasizes the importance of accurate diagnosis and effective treatment. Strategic options are necessary to improve the diagnosis of anxiety disorders, potentially enhancing QOL and medical outcome in patients with ESRD.

Association of Visual Tracking Metrics With Post-concussion Symptomatology.

Attention impairment may provide a cohesive neurobiological explanation for clusters of clinical symptoms that occur after a concussion; therefore, objective quantification of attention is needed. Visually tracking a moving target is an attention-dependent sensorimotor function, and eye movement can be recorded easily and objectively to quantify performance. Our previous work suggested the utility of gaze-target synchronization metrics of a predictive visual tracking task in concussion screening and recovery monitoring. Another objectively quantifiable performance measure frequently suggested for concussion screening is simple visuo-manual reaction time (simple reaction time, SRT). Here, we used visual tracking and SRT tasks to assess changes between pre- and within-2-week post-concussion performances and explore their relationships to post-concussion symptomatology. Athletes participating in organized competitive sports were recruited. Visual tracking and SRT records were collected from the recruited athlete pool as baseline measures over a 4-year period. When athletes experienced a concussion, they were re-assessed within 2 weeks of their injury. We present the data from a total of 29 concussed athletes. Post-concussion symptom burden was assessed with the Rivermead Post-Concussion Symptoms Questionnaire and subscales of the Brain Injury Screening Questionnaire. Post-concussion changes in visual tracking and SRT performance were examined using a paired t-test. Correlations of changes in visual tracking and SRT performance to symptom burden were examined using Pearson's coefficients. Post-concussion changes in visual tracking performance were not consistent among the athletes. However, changes in several visual tracking metrics had moderate to strong correlations to symptom scales (r up to 0.68). On the other hand, while post-concussion SRT performance was reduced (p < 0.01), the changes in the performance metrics were not meaningfully correlated to symptomatology (r ≤ 0.33). Results suggest that visual tracking performance metrics reflect clinical symptoms when assessed within 2 weeks of concussion. Evaluation of concussion requires assessments in multiple domains because the clinical profiles are heterogeneous. While most individuals show recovery within a week of injury, others experience prolonged recovery periods. Visual tracking performance metrics may serve as a biomarker of debilitating symptoms of concussion implicating attention as a root cause of such pathologies.

Visual Tracking in Development and Aging.

A moving target is visually tracked with a combination of smooth pursuit and saccades. Human visual tracking eye movement develops through early childhood and adolescence, and declines in senescence. However, the knowledge regarding performance changes over the life course is based on data from distinct age groups in isolation using different procedures, and thus is fragmented. We sought to describe the age-dependence of visual tracking performance across a wide age range and compare it to that of simple visuo-manual reaction time. We studied a cross-sectional sample of 143 subjects aged 7-82 years old (37% male). Eye movements were recorded using video-oculography, while subjects viewed a computer screen and tracked a small target moving along a circular trajectory at a constant speed. For simple reaction time (SRT) measures, series of key presses that subjects made in reaction to cue presentation on a computer monitor were recorded using a standard software. The positional precision and smooth pursuit velocity gain of visual tracking followed a U-shaped trend over age, with best performances achieved between the ages of 20 and 50 years old. A U-shaped trend was also found for mean reaction time in agreement with the existing literature. Inter-individual variability was evident at any age in both visual tracking and reaction time metrics. Despite the similarity in the overall developmental and aging trend, correlations were not found between visual tracking and reaction time performances after subtracting the effects of age. Furthermore, while a statistically significant difference between the sexes was found for mean SRT in the sample, a similar difference was not found for any of the visual tracking metrics. Therefore, the cognitive constructs and their neural substrates supporting visual tracking and reaction time performances appear largely independent. In summary, age is an important covariate for visual tracking performance, especially for a pediatric population. Since visual tracking performance metrics may provide signatures of abnormal neurological or cognitive states independent of reaction time-based metrics, further understanding of age-dependent variations in normal visual tracking behavior is necessary.

Possible Medication-Resistant Deficits in Adult ADHD.

OBJECTIVE: The nature of ADHD, especially in adulthood, is not well-understood. Therefore, we explored subcomponents of attention in adult ADHD. METHOD: Twenty-three adults with ADHD were tested on neurocognitive and visual tracking performance both while on their regular prescription stimulant medication and while abstaining from the medication for 1 day. Pairwise comparisons to 46 two-for-one matched normal controls were made to detect medication-resistant effects of ADHD, and within-participant comparisons were made to detect medication-sensitive effects in patients. RESULTS: Even when on medication, patients performed more poorly than controls on a spatial working memory task, and on visual tracking and simple reaction time tasks immediately following other attention-demanding tasks. Patients' visual tracking performance degraded while off-medication in a manner consistent with reduced vigilance. CONCLUSION: There may be persistent cognitive impairments in adult ADHD despite medication. In addition, the benefit of stimulants seems reduced under cognitive fatigue.

Frequency Responses to Visual Tracking Stimuli May Be Affected by Concussion.

Human visual tracking performance is known to be reduced with an increase of the target's speed and oscillation frequency, but changes in brain states following a concussion may alter these frequency responses. The goal of this study was to characterize and compare frequency-dependent smooth pursuit velocity degradation in normal subjects and patients who had chronic postconcussion symptoms, and also examine cases of acutely concussed patients. Eye movements were recorded while subjects tracked a target that moved along a circular trajectory of 10° radius at 0.33, 0.40, or 0.67 Hz. Performance was characterized by the gain of smooth pursuit velocity, with reduced gain indicating reduced performance. The difference between normal and chronic patient groups in the pattern of decrease in the gain of horizontal smooth pursuit velocity as a function of the stimulus frequency reflected patients performing more poorly than normal subjects at 0.4 Hz while both groups performing similarly at 0.33 or 0.67 Hz. The performance of acute patients may represent yet another type of frequency response. The findings suggest that there may be ranges of stimulus frequencies that differentiate the effects of concussion from normal individuals.

Response of School Districts to the New York State Concussion Awareness and Management Act: Review of Policies and Procedures.

BACKGROUND: By 2014, all states implemented concussion laws that schools must translate into daily practice; yet, limited knowledge exists regarding implementation of these laws. We examined the extent to which concussion management policies and procedure (P&P) documents of New York State school districts comply with the State's Concussion Awareness and Management Act (the Act). We also aimed to identify barriers to compliance. METHODS: Forty-seven school districts provided P&P documents. We examined compliance with the Act and the relationship between compliance and each district's demographics. RESULTS: Compliance varied across school districts, with higher overall compliance in large city school districts compared to county districts. However, there was low compliance for several critical items. We found no statistically significant relationship between compliance and demographics. CONCLUSIONS: School districts need to increase compliance with concussion legislation to ensure the adequate implementation necessary for the law to impact health and educational outcomes. The results provide important information to individuals charged with the responsibility of implementation and ultimately reducing the negative outcomes associated with brain injuries in schools.

Degradation of Binocular Coordination during Sleep Deprivation.

To aid a clear and unified visual perception while tracking a moving target, both eyes must be coordinated, so the image of the target falls on approximately corresponding areas of the fovea of each eye. The movements of the two eyes are decoupled during sleep, suggesting a role of arousal in regulating binocular coordination. While the absence of visual input during sleep may also contribute to binocular decoupling, sleepiness is a state of reduced arousal that still allows for visual input, providing a context within which the role of arousal in binocular coordination can be studied. We examined the effects of sleep deprivation on binocular coordination using a test paradigm that we previously showed to be sensitive to sleep deprivation. We quantified binocular coordination with the SD of the distance between left and right gaze positions on the screen. We also quantified the stability of conjugate gaze on the target, i.e., gaze-target synchronization, with the SD of the distance between the binocular average gaze and the target. Sleep deprivation degraded the stability of both binocular coordination and gaze-target synchronization, but between these two forms of gaze control the horizontal and vertical components were affected differently, suggesting that disconjugate and conjugate eye movements are under different regulation of attentional arousal. The prominent association found between sleep deprivation and degradation of binocular coordination in the horizontal direction may be used for a fit-for-duty assessment.

Chronic Post-Concussion Neurocognitive Deficits. II. Relationship with Persistent Symptoms.

Individuals who sustain a concussion may continue to experience problems long after their injury. However, it has been postulated in the literature that the relationship between a concussive injury and persistent complaints attributed to it is mediated largely by the development of symptoms associated with posttraumatic stress disorder (PTSD) and depression. We sought to characterize cognitive deficits of adult patients who had persistent symptoms after a concussion and determine whether the original injury retains associations with these deficits after accounting for the developed symptoms that overlap with PTSD and depression. We compared the results of neurocognitive testing from 33 patients of both genders aged 18-55 at 3 months to 5 years post-injury with those from 140 control subjects. Statistical comparisons revealed that patients generally produced accurate responses on reaction time-based tests, but with reduced efficiency. On visual tracking, patients increased gaze position error variability following an attention demanding task, an effect that may reflect greater fatigability. When neurocognitive performance was examined in the context of demographic- and symptom-related variables, the original injury retained associations with reduced performance at a statistically significant level. For some patients, reduced cognitive efficiency and fatigability may represent key elements of interference when interacting with the environment, leading to varied paths of recovery after a concussion. Poor recovery may be better understood when these deficits are taken into consideration.