Computerised neuropsychological testing

The Effect of Ball Heading and Subclinical Concussion On the Neuromuscular Control Of The Lower Limb: A Systematic Review

Background

Soccer is unique among sports because it is the only sport that involves purposeful use of the head to control, pass, or shoot the ball. Over the previous five years, a relationship between lower extremity (LE) injury and sports related concussion (SRC) has been established in various sporting populations. Athletes at the high school, collegiate, and professional levels have demonstrated a greater risk for sustaining a LE injury post SRC. The purpose of this systematic review was to examine the relationship of the SRC with the incidence of LE injuries.

Methods

Ten databases were searched with the following keywords: Lower limb, ball heading, neuromuscular control, concussion, MEDLINE, Ovid MEDLINE(R) Daily, and Ovid MEDLINE(R), EMBASE, and Scopus. The search was limited to English-language and peer-reviewed publications, until 15/12/2022. The PEDro scale was used for the assessment of the risk of bias among the included studies. All included papers were qualitatively analyzed.

Results

A total of 834 studies were identified and 10 articles (four concussion-MSK biomechanics, six concussion-MSK injury) were included in the qualitative analyses. Included papers ranged from low to high quality. Due to the heterogeneous nature of the included study designs, quantitative meta-analysis was unable to be performed. All four of the included concussion-MSK biomechanics studies demonstrated, to some degree, that worse cognitive performance was associated with lower extremity MSK biomechanical patterns suggestive of greater risk for MSK injury. Among the six injury related studies, two investigations failed to determine group differences in cognitive performance between subsequently injured and non-injured athletes.

Conclusion

More research is needed to better understand the relationship of SRC and lower extremity injuries and the extent to which they are related to concussions and/or repetitive neurotrauma after ball heading sustained in soccer.

Level of Evidence

2.

Correlation between Ocular and Vestibular Abnormalities and Convergence Insufficiency in Post-Concussion Syndrome

The vestibular and oculomotor/visual systems are commonly affected in post-concussion syndrome (PCS). Convergence insufficiency (CI) is the most common ocular abnormality after concussion. Electrovestibulography (EVestG) is a relatively new non-invasive method that measures the peripheral vestibular responses; it has shown abnormal vestibular responses in a PCS. Here, we report the results of investigating the correlation between the vestibular and oculomotor systems in PCS population using EVestG and CI measures. Forty-eight PCS patients were tested using EVestG, out of which 20 also completed the Rivermead post-concussion questionnaire (RPQ). An EVestG feature (Field Potential (FP)-area) was extracted from the stationary part of the EVestG signals. A neuro-ophthalmologist (author BM) measured participants' CI at near vision using cross-cover examination and a prism-bar. Results indicate: (1) vestibular abnormality (i.e. FP-area) and CI values are significantly correlated in PCS (R = 0.68, p < .01), and (2) there are significant correlations between severity of concussion (i.e. RPQ3) and CI (R = 0.70, p < .01) and between RPQ3 and FP-area (R = -0.56, p < .02). To the best of our knowledge, this is the first study that objectively demonstrates a significant positive correlation between the CI and vestibular systems' abnormality. These findings are scientifically important as they help localise the pathology of PCS, and are clinically valuable as they help physicians in their decision-making about PCS diagnosis and rehabilitation strategies.

Testing the hybrid battery approach to evaluating sports-related concussion in the National Hockey League: A factor analytic study

Objective: There has been an increased interest in the use of "Hybrid" neuropsychological test batteries to evaluate neurocognitive functioning prior to and following sports-related concussion. Typically, these test batteries include a combination of traditional "paper and pencil" (P&P) and computerized measures. The National Hockey League (NHL) employs a Hybrid approach consisting of ImPACT and a brief battery of P&P measures. The purpose of this paper was to examine the NHL's Hybrid model by means of factor analytic techniques in order to determine the extent to which the measures included in the battery are independent of each other or share common variance.Method: Principal components analyses with promax rotations were conducted on the P&P measures alone and when combined with ImPACT. A total of 360 recently concussed NHL players underwent testing using the combined hybrid battery.Results: A principal components analysis with promax rotation of the combined hybrid battery yielded 5 factors (Verbal Learning/Memory, Visual Learning/Memory, Processing Speed/Executive Functioning, Cued/Recognition Memory and Reaction Time/Speed). The factors appear to be relatively independent of each other with the P&P measures comprising the Verbal Learning/Memory, Visual Learning/Memory, and Processing Speed/Executive Functioning and ImPACT loading on the Cued/Recognition Memory and Reaction Time/Speed factors.Conclusions: These data provide support for the Hybrid model with evidence that the P&P measures and ImPACT do not measure the same domains of cognitive functioning. The clinical implications of the findings are discussed in detail.

Sport-Related Concussion: Evaluation, Treatment, and Future Directions

Sport-related concussion (SRC) is a highly prevalent injury predominantly affecting millions of youth through high school athletes every year. In recent years, SRC has received a significant amount of attention due to potential for long-term neurologic sequelae. However, the acute symptoms and possibility of prolonged recovery account for the vast majority of morbidity from SRC. Modifying factors have been identified and may allow for improved prediction of a protracted course. Potential novel modifying factors may include genetic determinants of recovery, as well as radiographic biomarkers, which represent burgeoning subfields in SRC research. Helmet design and understanding the biomechanical stressors on the brain that lead to concussion also represent active areas of research. This narrative review provides a general synopsis of SRC, including relevant definitions, current treatment paradigms, and modifying factors for recovery, in addition to novel areas of research and future directions for SRC research.

Management of concussion in soccer

BACKGROUND

When participating in contact sports, (mild) head trauma is a common incident-observed in both professional and amateur sports. When head trauma results in transient neurological impairment, a sports-related concussion has occurred. Acute concussion, repetitive concussions, as well as cumulative "sub-concussive" head impacts may increase the risk of developing cognitive and behavioral deficits for athletes, as well as accelerated cerebral degeneration. While this concept has been well established for classic contact sports like American Football, Rugby, or Boxing, there is still an awareness gap for the role of sports-related concussion in the context of the world's most popular sport-Soccer.

METHODS

Here, we review the relevance of sport-related concussion for Soccer as well as its diagnosis and management. Finally, we provide insight into future directions for research in this field.

RESULTS

Soccer fulfills the criteria of a contact sport and is characterized by a high incidence of concussion. There is ample evidence that these events cause functional and structural cerebral disorders. Furthermore, heading, as a repeat sub-concussive impact, has been linked to structural brain changes and neurocognitive impairment. As a consequence, recommendations for the diagnosis and management of concussion in soccer have been formulated by consensus groups. In order to minimize the risk of repetitive concussion in soccer the rapid and reliable side-line diagnosis of concussion with adoption of a strict remove-from-play protocol is essential, followed by a supervised, graduated return-to-play protocol. Recent studies, however, demonstrate that adherence to these recommendations by players, coaches, clubs, and officials is insufficient, calling for stricter enforcement. In addition, future research to solidify the pathophysiological relevance of concussion for soccer athletes seems to be needed. Advanced neuroimaging and neurochemical biomarker analyses (e.g. S100β, tau and neurofilament light (NfL)) may assist in detecting concussion-related structural brain changes and selecting athletes at risk for irreversible damage.

CONCLUSION

Sports-related concussion represents a genuine neurosurgical field of interest. Given the high socioeconomic relevance, neurosurgeons should get involved in prevention and management of concussion in soccer.

Sensitivity of the Cogstate Test Battery for Detecting Prolonged Cognitive Alterations Stemming From Sport-Related Concussions

OBJECTIVE

To determine if the Cogstate test battery contains the requisite sensitivity to detect prolonged cognitive alterations.

METHODS

One hundred twenty collegiate athletes (71 with a history of concussion; 49 controls) completed the Cogstate test battery, to which we added a 2-back condition. In addition to the Cogstate clinical (transformed variables), we analyzed the raw data.

RESULTS

The clinical variables failed to reveal any group differences. Further, although the raw data failed to reveal group differences for tasks measuring lower-level cognition, group differences were observed for accuracy on the 1- and 2-back tasks, which require multiple aspects of higher cognition. The overall classification accuracy was higher using the raw data than the clinical variables. The combined sensitivity of the 1- and 2-back task was moderate and specificity was high.

CONCLUSIONS

These results suggest that using the raw scores over clinical variables increases the sensitivity of the test battery. Moreover, these results add another piece of evidence suggesting that concussive injuries are associated with subtle long-term alterations in aspects of higher cognition. Importantly, these deficits would have gone unobserved if we had relied solely on automated clinical variables. The current results further our scientific understanding of concussion and may be used to advance clinical practices.

Sport Concussion and the Female Athlete

Sport concussion (SC) has emerged as a major health concern in the medical community and general public owing to increased research and media attention, which has primarily focused on male athletes. Female athletes have an equal, if not increased, susceptibility to SC. An ever-growing body of research continues to compare male and female athletes in terms of SC before and after an injury. Clinicians must be cognizant of this literature to make evidence-based clinical decision when providing care to female athletes and discern between dated and/or unsupported claims in terms of SC.

The test-retest reliability of three computerized neurocognitive tests used in the assessment of sport concussion

Computerized neurocognitive tests (CNTs) are widely used at all competitive levels of sport to assess sport concussion (SC). Whereas there are multiple CNTs available, little is known about how some of the most popular platforms compare. The purpose of this study was to investigate the test-retest reliability of the Automated Neuropsychological Assessment Metrics (ANAM), Concussion Vital Signs (CVS) and the Immediate Postconcussion and Cognitive Testing battery (ImPACT) using clinically relevant time points in healthy college-age participants. Participants were healthy college-age students (N=128) randomly assigned into one of three groups which were administered ANAM, CVS, or ImPACT at Days 1, 45 and 50. Intraclass correlation coefficients (ICCs) and Pearson correlations were used to assess reliability of the various CNT scores and subtest scores between time points. Participants were tested approximately 47.1±2.75days after time point 1 and approximately 7.0±2.45days after time point 2. ICC values ranged from 0.18 (Procedural Reaction Time) to 0.53 (Mathematical Processing and Simple Reaction Time 1) for ANAM, 0.14 (Continuous Performance Test) to 0.85 (Reaction Time) for CVS, and 0.19 (Verbal Memory) to 0.89 (Visual Motor Speed) for ImPACT. Significant improvements (p<0.05) across time were observed for (7/10) CNS Vital Signs composite scores, but no additional significant changes in performance were observed for the remaining CNTs. Overall, weak to strong reliability coefficients for ANAM, CVS, and ImPACT were observed when using clinically relevant time points of repeated administration.

Sports-related Concussion in Children and Adolescents

Concussions are becoming increasingly important to manage properly as sports participation continues to rise. Repeated injuries occurring before the brain has had a chance to recover from an initial insult are particularly dangerous and must be prevented. Although much national media attention has been devoted to concussions in professional sports, it is important to appreciate that athletes in any age group, children and adolescents in particular, are at risk of sports-related concussion. It is crucial to remove an athlete from play any time concussion is suspected. Once removed from play, recovery then begins with a period of cognitive and physical rest, followed by a gradual return to cognitive and athletic activities as symptoms resolve. Children and adolescents pose a unique challenge to the clinician managing their recovery, as the physical and cognitive rest periods required often involve time away from school and sports, which can be academically detrimental and socially isolating. Recently developed sideline assessment tools have greatly aided the urgent sideline assessment of an athlete suspected of having a concussion. In this article, a brief review of current guidelines is presented in tandem with the authors' preferred treatment of concussion.

Fundamental study of functional changes to female brain induced by pregnancy and childbirth

In this study, we investigated variations in a women's cognitive function during a time of pregnancy and childbearing. Volunteers were composed of 114 healthy women ranging in age from 23-43 years with an average age of 31.8 years (SD=4.3). Further, 79 were pregnant and 35 were not pregnant. All the pregnant women were expecting their first child and continued with the cognitive function analysis after their childbearing was concluded. We instructed the pregnant women to carry out five kinds of tests: simple reaction, SR; choice reaction, CR; working memory, WM; one card learning, OC; and divided attention, DA using card games through a cognitive function test called "CogHealth", and compared them to a nonpregnant group. In the results of the four measurement tasks (SR, CR, WM, and DA), there were no significant differences across the three groups in the responses with the tasks. However, the response times relating to the OC learning in the postnatal women were significantly smaller, as contrasted with the times for the pregnant and the nonpregnant women (F(2,144)=4.248, P <; 0.05). Furthermore, we compared their cognitive functions between pregnant and postnatal states in corresponding volunteers in the responses with the same tasks. We also demonstrated the fact that postnatal women responded more quickly to tasks in the OC (t(32)=2.95, P <; 0.01) and the WM (t(32)=3.03, P <; 0.01) categories than responses to performing the tasks during their pregnancy. Our findings support the idea that the functions of pregnant/postnatal women are not failing, or rather postnatal women are more responsive in their reaction times with their memories by 2.7-6.2%, than the responses in both pregnant and nonpregnant women.

The Acute Management of Sport Concussion in Pediatric Athletes

During the past two decades the focus on sport concussion has increased significantly. Young athletes represent the most vulnerable population to sustain a sport concussion yet receive the least amount of attention. Specifically, young athletes who sustain a sport concussion can go unrecognized and continue to participate in sport putting them at an increased risk for a more significant injury. The purpose of this review is to provide a clinical framework for the evaluation and management of sport concussion. In addition, this review provides considerations for health care professionals in regard to clinical measures and follow-up strategies during the acute phase following concussion in young concussed athletes following injury.

Supervision and computerized neurocognitive baseline test performance in high school athletes: an initial investigation

CONTEXT

Computerized neuropsychological testing batteries have provided a time-efficient and cost-efficient way to assess and manage the neurocognitive aspects of patients with sport-related concussion. These tests are straightforward and mostly self-guided, reducing the degree of clinician involvement required by traditional clinical neuropsychological paper-and-pencil tests.

OBJECTIVE

To determine if self-reported supervision status affected computerized neurocognitive baseline test performance in high school athletes.

DESIGN

Retrospective cohort study.

SETTINGS

Supervised testing took place in high school computer libraries or sports medicine clinics. Unsupervised testing took place at the participant's home or another location with computer access.

PATIENTS OR OTHER PARTICIPANTS

From 2007 to 2012, high school athletes across middle Tennessee (n = 3771) completed computerized neurocognitive baseline testing (Immediate Post-Concussion Assessment and Cognitive Testing [ImPACT]). They reported taking the test either supervised by a sports medicine professional or unsupervised. These athletes (n = 2140) were subjected to inclusion and exclusion criteria and then matched based on age, sex, and number of prior concussions.

MAIN OUTCOME MEASURE(S)

We extracted demographic and performance-based data from each de-identified baseline testing record. Paired t tests were performed between the self-reported supervised and unsupervised groups, comparing the following ImPACT baseline composite scores: verbal memory, visual memory, visual motor (processing) speed, reaction time, impulse control, and total symptom score. For differences that reached P < .05, the Cohen d was calculated to measure the effect size. Lastly, a χ(2) analysis was conducted to compare the rate of invalid baseline testing between the groups. All statistical tests were performed at the 95% confidence interval level.

RESULTS

Self-reported supervised athletes demonstrated better visual motor (processing) speed (P = .004; 95% confidence interval [0.28, 1.52]; d = 0.12) and faster reaction time (P < .001; 95% confidence interval [-0.026, -0.014]; d = 0.21) composite scores than self-reported unsupervised athletes.

CONCLUSIONS

Speed-based tasks were most affected by self-reported supervision status, although the effect sizes were relatively small. These data lend credence to the hypothesis that supervision status may be a factor in the evaluation of ImPACT baseline test scores.

Infant motor development and cognitive performance in early old age: the Helsinki Birth Cohort Study

Motor development and cognitive development in childhood have been found to be fundamentally interrelated, but less is known about the association extending over the life course. The aim of this study was to examine the association between early motor development and cognitive performance in early old age. From men and women belonging to the Helsinki Birth Cohort Study, who were born between 1934 and 1944 and resided in Finland in 1971, 1279 participated in cognitive performance tests (CogState®, version 3.0.5) between 2001 and 2006 at an average age of 64.2 years (SD 3.0). Of these, age at first walking extracted from child welfare clinic records was available for 398 participants. Longer reaction times in cognitive tasks measuring simple reaction time (SRT), choice reaction time (CRT), working memory (WM), divided attention (DA), and associated learning (AL) indicated poorer cognitive performance. Adjustment was made for sex, age at testing, father's occupational status and own highest attained education, and occupation in adulthood. Average age of learning to walk was 12.2 months (SD 2.1). After adjusting for covariates, earlier attainment of learning to walk was associated with shorter reaction times in cognitive performance tasks (SRT 10.32 % per month, 95 % CI 0.48-21.12, p = 0.039; CRT 14.17 % per month, 95 % CI 3.75-25.63, p = 0.007; WM 15.14 % per month, 95 % CI 4.95-26.32, p = 0.003). People who learned to walk earlier had better cognitive performance in early old age. The earlier attainment of motor skills may track over to early old age and possibly reflect greater cognitive reserve in older age.

Update on sports concussion

Over the past 20 years, sports concussion has become one of the most researched topics in sports medicine. Significant resources have been allocated to the study of this issue, with a dramatic increase in information concerning most aspects of this common sports injury. In light of this considerable increase in research, this review is offered to provide clinicians involved in the care of athletes a summary of key features of the evaluation and management of sports concussion with attention to recent contributions to the literature.

Multimodal evaluation and management of children with concussion: using our heads and available evidence

BACKGROUND

Significant attention has been focused on concussions in children, but a dearth of research evidence exists supporting clinical evaluation and management.

AIM

The primary objective of this review paper is to describe a multimodal, developmentally adapted, standardized concussion assessment and active rehabilitation approach for children as young as 5 years old.

METHODS

This study reviews the CDC-funded research programme, including the development of tools for post-concussion symptom assessment involving the child and parent, measurement of specific neurocognitive functions and assessment of dynamic cognitive exertional effects.

RESULTS

A clinical approach to active, individualized, moderated concussion rehabilitation management is presented, including a 10-step guide to symptom management, with a specific focus on the school challenges faced by the recovering student.

CONCLUSION

To better inform concussion practice across the developmental age spectrum, a significant need exists for further research evidence to refine clinical assessment methods and develop effective treatment approaches.

Cerebral Concussion in Sport: An Overview

Sports-related concussions are ubiquitous in contact and collision sports at all levels of play and across a broad age range. Once thought to be a nuisance injury, it is now recognized that these brain injuries may lead to chronic neurocognitive impairment if not managed properly. This paper provides a broad overview of the research and clinical data that have emerged in this rapidly growing area. Included in the review are discussions of injury definition, pathophysiology, signs and symptoms, epidemiology, potential long-term consequences, assessment, and psychological factors. Issues of prevention and education are discussed in light of further increasing awareness of this injury.

An evaluation on the neuropsychological tests used in the assessment of postchemotherapy cognitive changes in breast cancer survivors

OBJECTIVES

The choice of appropriate neuropsychological tests is important in evaluating the onset, severity, duration, and site of cognitive changes in postchemotherapy breast cancer survivors. This literature review is designed to evaluate and provide a summary of suitable neuropsychological tests to determine cognitive changes in breast cancer survivors.

METHOD

A literature search restricted to publications in English before June 2011 was performed using the following combination of keywords: "neuropsychological assessments," "breast cancer," "chemotherapy," and "cognitive impairment." Only observational studies that performed cognitive assessments on breast cancer survivors were included. The neuropsychological assessments were grouped as "objective" (traditional batteries and screening tests), "subjective," or "computerized."

RESULTS

Of the 43 studies extracted, memory (88 %) and attention/concentration (88 %) are the two most commonly assessed domains. A majority (63 %) employed the use of Wechsler Adult Intelligent Scale (an objective test), while only 49 % incorporated subjective assessments to assess perceived cognitive impairment. Computerized tests received low popularity (28 %) despite their numerous advantages, which include overcoming the language- and cultural-dependent limitations of traditional objective tests.

CONCLUSIONS

In the selection of a suitable neuropsychological tool to determine the onset, severity, site, and duration of cognitive changes in breast cancer survivors, incorporation of both subjective and objective tests is essential to facilitate a comprehensive assessment. With more validation work performed in future studies, it may be feasible to employ computerized neuropsychological assessments in both clinical and research settings.

Group versus individual administration affects baseline neurocognitive test performance

BACKGROUND

Computer-based tests are widely used for the purpose of documenting baseline neurocognitive function, and athletes are often tested in groups. At present, there is limited research on the effects of administering these tests in a group versus individual setting.

HYPOTHESIS

Athletes assessed with neurocognitive tests in groups would show decreased performance compared with those assessed individually.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

High school athletes completed preseason baseline neurocognitive tests either in groups in their school or individually in a private neuropsychological clinic (with no significant between-group differences in sex, history of concussion, and attention deficit disorder/learning disability). All athletes completed the ImPACT (Immediate Post-Concussion Assessment and Cognitive Testing) test battery on 1 occasion, which yielded scores in the area of verbal memory, visual memory, motor processing speed, reaction time, and symptom scores.

RESULTS

Athletes in the group setting scored significantly lower on verbal memory (mean 83.4 vs 86.5; P = .003), visual memory (mean 71.6 vs 76.7; P = .0001), motor processing speed (mean 35.6 vs 38.4; P = .0001), and reaction time (mean 0.61 vs 0.57; P = .001), but not symptom scores (mean 6.1 vs 4.4; P = .11), and exhibited a greater rate of invalid baselines. Similar results were obtained after excluding athletes with attention deficit disorder/learning disability and/or a history of concussion.

CONCLUSION

Administering baseline neurocognitive testing to athletes in a group setting may introduce extraneous error, negatively affecting test performance.

Boxing-related head injuries

Fatalities in boxing are most often due to traumatic brain injury that occurs in the ring. In the past 30 years, significant improvements in ringside and medical equipment, safety, and regulations have resulted in a dramatic reduction in the fatality rate. Nonetheless, the rate of boxing-related head injuries, particularly concussions, remains unknown, due in large part to its variability in clinical presentation. Furthermore, the significance of repeat concussions sustained when boxing is just now being understood. In this article, we identify the clinical manifestations, pathophysiology, and management of boxing-related head injuries, and discuss preventive strategies to reduce head injuries sustained by boxers.

Sport-related concussion in adolescents

Sport-related concussion is a common problem encountered by pediatricians and other primary care physicians. Assessment of concussion is based on clinical evaluation. The Zurich consensus statement provides a basic framework to guide concussion management decisions and recommends an individualized approach and the exercising of clinical judgment in return-to-play decisions. This article reviews practice aspects of concussion for the adolescent athletes who present in the primary care office or clinic setting.

Slower reaction times and impaired learning in young adults with birth weight <1500 g

OBJECTIVE

Children with very low birth weight (VLBW; <1500 g) perform worse on cognitive tests than do children who are born at term. Whether this difference persists into adulthood has been little studied. We assessed core neurocognitive abilities (processing speed, working memory, attention, and learning capacity) in young adults with VLBW and in term-born control subjects.

METHODS

In conjunction with the Helsinki Study of Very Low Birth Weight Adults, 147 VLBW and 171 control subjects who were aged 18 to 27 years and did not have neurosensory impairments performed a computerized test battery (CogState Ltd, Melbourne, Australia). T tests and linear regression models were used. Cohen's d was used to express effect size (ES).

RESULTS

VLBW adults had slower reaction times than did control subjects on all 5 tasks: simple reaction time (mean difference: 4.0% [95% confidence interval (CI): 1.1%-7.0%]; ES: 0.30), choice reaction time (mean difference: 3.2% [95% CI: 0.3%-6.2%]; ES: 0.24), working memory (mean difference: 8.4% [95% CI: 3.7%-13.4%]; ES: 0.40), divided attention (mean difference: 7.2% [95% CI: 2.7%-11.9%]; ES: 0.36), and associated learning reaction time (mean difference: 6.4% [95% CI: 1.3%-11.9%]; ES: 0.28). In addition, VLBW adults showed impaired learning abilities on the associated learning task (percentage of correct responses: 85.7 vs 80.2; P < .001; ES: 0.64). The results were little affected by adjustment for confounders.

CONCLUSIONS

Nonimpaired VLBW individuals exhibited slower psychomotor speed and lower accuracy on the associated learning task. These results indicate that very preterm birth, even when obvious neurosensory deficits are absent, may have long-term consequences on core neurocognitive abilities.

Consensus statement on concussion in sport - the Third International Conference on Concussion in Sport held in Zurich, November 2008

This paper is a revision and update of the recommendations developed following the 1st (Vienna) and 2nd (Prague) International Symposia on Concussion in Sport. The Zurich Consensus statement is designed to build on the principles outlined in the original Vienna and Prague documents and to develop further conceptual understanding of this problem using a formal consensus-based approach. A detailed description of the consensus process is outlined at the end of this document under the "background" section (see Section 11). This document is developed for use by physicians, therapists, certified athletic trainers, health professionals, coaches and other people involved in the care of injured athletes, whether at the recreational, elite, or professional level. While agreement exists pertaining to principal messages conveyed within this document, the authors acknowledge that the science of concussion is evolving, and therefore management and return-to-play (RTP) decisions remain in the realm of clinical judgment on an individualized basis. Readers are encouraged to copy and distribute freely the Zurich Consensus document and/or the Sports Concussion Assessment Tool (SCAT2) card, and neither is subject to any copyright restriction. The authors request, however, that the document and/or the SCAT2 card be distributed in their full and complete format.

Using a sledgehammer to crack a walnut: the modern management of concussion

Sports concussion is still poorly understood and therefore difficult to prevent and manage

Evaluation of Cognitive Function Associated With Chemotherapy: A Review of Published Studies and Recommendations for Future Research

Purpose

There is evidence that some cancer survivors suffer cognitive impairment after chemotherapy. Determining if a patient has cognitive impairment is challenging, especially because impairment is usually subtle.

Patients and Methods

We assessed the design of studies evaluating cognitive function during or after chemotherapy in adult patients with solid tumors. We also reviewed methods used to evaluate cognitive function in subjects with other diseases and make recommendations for future studies.

Results

We identified 22 studies that met our criteria: 82% included women with breast cancer. Eight studies were longitudinal, 12 were cross-sectional, and two were follow-ups of cross-sectional studies. Sixteen studies used a battery of neuropsychological (NP) tests to assess subjects, and 13 included a control group. Ten studies (45%) had no explicit definition of cognitive impairment; most others used z scores or T scores and defined impairment based on standard deviations below the mean, but there was no consistency in for the cutoff point used or the number of tests required.

Conclusion

There is no consistency in defining cognitive impairment, in the NP batteries used, or in statistical methods in studies of cognitive function of cancer patients. We suggest guidelines to define criteria for cognitive impairment. Use of summary scores and control groups is recommended. Practice effect should be adjusted for in longitudinal studies. A balance is needed between comprehensive batteries and briefer tests, which still need to be sensitive to mild impairment.

Neuropsychological profile of acute alcohol intoxication during ascending and descending blood alcohol concentrations

Numerous studies have investigated the effects of alcohol on motor processes during rising and declining blood alcohol concentrations (BAC), however, relatively little research has examined the alcohol-induced impairment of cognitive performance on the two limbs of the BAC curve. This experiment administered a neuropsychological test battery to assess the degree to which rising and declining BACs during an acute dose of alcohol impair nine cognitive processes within an individual. In all, 20 healthy male social drinkers (university students) were assigned to one of two groups (n = 10) who received a beverage containing either 0.0 g/kg (placebo) or 0.65 g/kg alcohol and performed the test battery when BAC was increasing and was decreasing. Comparisons of alcohol and placebo groups revealed impairment (slower response and/or increased errors) in seven of the cognitive processes: long-term verbal memory; information processing; declarative memory; inhibitory control; short-term visual memory; long-term visual memory, and visual-spatial working memory. However, some processes were impaired only during rising BACs whereas the impairment of others during declining BACs was evident only by an increase in errors. These results show cognitive tasks performed by an individual are not similarly affected by rising and declining BACs, and call attention to the importance of assessing both speed and accuracy on both limbs of the BAC curve. The particular cognitive processes differentially affected by rising vs declining BACs raised the possibility that acute alcohol intoxication may impair one cerebral hemisphere to a greater degree than the other, and this could be explored by neuroimaging techniques.

The use, abuse, and future of neuropsychologic testing in mild traumatic brain injury

A comparison is made between abbreviated formal neuropsychologic testing programs and computerized neuropsychologic programs such as ImPACT, Headminders, CogSport, and others. Issues of time, cost, need for supervision, liability, and validation are discussed. Specific time and monetary costs per athlete are calculated for each program. The estimated cost is between $22 and $27 per athlete for abbreviated formal testing and between $669 and $677 per athlete for computerized testing. Because of the significant time and monetary costs of neuro-psychologic testing, its lack of validation in deter-mining recovery, limited validation and utility in diagnosing concussion, and its numerous logistic concerns, its widespread use is probably not justified until appropriate data are published and costs contained. Recommendations for alternative evaluation techniques are suggested.

Cognition in the days following concussion: comparison of symptomatic versus asymptomatic athletes

BACKGROUND

Concussion is a common neurological injury occurring during contact sport. Current guidelines recommend that no athlete should return to play while symptomatic or displaying cognitive dysfunction. This study compared post-concussion cognitive function in recently concussed athletes who were symptomatic/asymptomatic at the time of assessment with that of non-injured (control) athletes.

METHODS

Prospective study of 615 male Australian Rules footballers. Before the season, all participants (while healthy) completed a battery of baseline computerised (CogSport) and paper and pencil cognitive tasks. Sixty one injured athletes (symptomatic = 25 and asymptomatic = 36) were reassessed within 11 days of being concussed; 84 controls were also reassessed. The serial cognitive function of the three groups was compared using analysis of variance.

RESULTS

The performance of the symptomatic group declined at the post-concussion assessment on computerised tests of simple, choice, and complex reaction times compared with the asymptomatic and control groups. The magnitude of changes was large according to conventional statistical criteria. On paper and pencil tests, the symptomatic group displayed no change at reassessment, whereas large improvements were seen in the other two groups.

CONCLUSION

Injured athletes experiencing symptoms of concussion displayed impaired motor function and attention, although their learning and memory were preserved. These athletes displayed no change in performance on paper and pencil tests in contrast with the improvement observed in asymptomatic and non-injured athletes. Athletes experiencing symptoms of concussion should be withheld from training and competition until both symptoms and cognitive dysfunction have resolved.

Repeat Mild Traumatic Brain Injury

Determining when it is safe for an athlete to return to play (RTP) after concussion is one of the most difficult decisions facing the team physician. There is significant variability in the evaluation and management of mild traumatic brain injury (mTBI). In the past decade, a tremendous amount of sport-specific research has improved our understanding of mTBI. The advent of neuro-psychologic (NP) testing batteries designed to assess concussive injury has improved the assessment of cognitive dysfunction that occurs in the absence of structural brain abnormalities. The severity of injury is determined by the nature, burden, and duration of symptoms. Athletes must be asymptomatic and have a normal neurologic and cognitive evaluation prior to RTP. Several factors aid in making the RTP decision, including age, the severity of injury, and history of prior mTBIs. Given the potential complications of mTBI, the RTP decision must be made using a thoughtful, individualized process.