Background/Objectives: Dual tasks are increasingly being employed in research on concussion, since they provide a somewhat more realistic representation of the demands athletes face on the field. While single cognitive and motor tasks have revealed persisting autonomic alterations in concussed athletes, the unique autonomic response required by a dual task remains unexplored in this population. The purpose of this study was to evaluate autonomic responses in asymptomatic athletes with a history of concussion (m = 5.46 months ± 2.00) following a complex dual task. Methods: Heart rate variability (HRV), a biomarker of autonomic regulation, was measured in 34 athletes (16 concussed, 18 controls) aged 17 to 24. HRV data were collected using the Polar H10 chest belt. Five-minute segments were extracted under four conditions: rest, following a cognitive task (switch task), after a dual task combining both motor and cognitive components, and after the same dual task preceded by 20 min of aerobic exercise. A series of 4 × 2 mixed-design ANOVAs were conducted to assess the differences between the conditions and groups. Results: The results indicated a significant increase in a global marker of HRV (i.e., the standard deviation of normal-to-normal intervals (SDNN)) following the switch task compared to rest (p = 0.014) only in concussed participants. These results suggest that the switch task may stimulate frontal regions and promote a parasympathetic response, as reflected by the rise in HRV. Notably, the effect of the switch task disappeared when combined with the motor component of the dual task, whether it was preceded by aerobic exercise or not. Conclusions: The dual task results indicate potential competing mechanisms between the motor and cognitive components of the task, which future studies using similar protocols should consider. Meanwhile, the switch task appears sufficiently demanding to reveal autonomic alterations, which, when measured through HRV, may constitute a relevant clinical tool for assessing athletes’ readiness to return to sport and academic study.

Objective: This study investigated gait and cognitive dual-task costs under a dual-task paradigm that was more challenging than the traditional tasks used in research. Methods: A total of 43 18–25-year-old male and female student athletes were recruited (20 asymptomatic concussed athletes who suffered at least one concussion 2.79–7.92 months before testing, 23 never concussed). Athletes performed a complex rapid decision-making and executive function computerized task while walking continuously and maintaining a predetermined speed on a non-motorized treadmill (6.5 km/h). The outcome measures were gait and cognitive dual-task costs. Results: Repeated-measures ANOVAs were conducted to evaluate group differences. Pearson correlations were conducted to evaluate the association between dual-task costs and concussion injury variables. The results showed that both groups experienced greater difficulty with dual-task performance related to gait, whereas only the concussion group exhibited poorer cognitive performance under the dual-task condition (both not significant). The significant correlation between time since injury and gait dual-task cost (r = −0.72, p < 0.001) indicated that athletes with a more recent concussion increased their gait speed whilst athletes with an older concussion reduced their gait speed during the dual-task. Moreover, the cognitive dual-task cost was significantly correlated to symptom recovery (r = 0.461, p = 0.047), suggesting that a longer recovery time from concussion is associated with an increased dual-task cost. Conclusions: While dual-task gait alterations were common to both groups, only individuals with a history of concussion showed specific cognitive impairments under dual-task conditions. The observed associations between dual-task costs and both time since injury and symptom recovery underscore the potential of complex dual-task assessments to provide nuanced insights into post-concussion recovery trajectories and to detect subtle, lingering deficits.

Gaps remain in our understanding of which factors contribute to concussion disclosure and how they contribute to this process, thereby limiting our ability to improve disclosure. This study aimed to characterize the most relevant extra-personal determinants of SC disclosure and to describe their influence on the disclosure process. To that aim, the first author conducted substantive qualitative interviews with nine university student–athletes and analyzed their content via constant comparative analysis (guided by Straussian grounded theory). Eleven (11) extra-personal concepts influencing concussion reporting were identified and described across two categories: Contextual Incentives and Socio-Cultural Pressures. These findings suggest that each identified concept can individually shape the context around the injury, creating either higher-stakes conditions that deter disclosure or lower-stakes conditions that encourage it. Further, the results posit that these concepts interact and collectively influence athletes’ decision-making process by modulating the perceived stakes of disclosing a concussion. If these findings hold true in more diverse populations and contexts, they suggest that adapting concussion prevention efforts to consider these contextual variables could improve SC disclosure. This study also highlights the benefits of using qualitative methods in the investigation of concussion reporting.

Objective Identify intra- and extra-personal factors influencing concussion disclosure in university athletes and describe their effects and interactions in an explanatory theoretical model. Design Qualitative research using Straussian Grounded Theory. Setting Semi-structured interviews. Participants 9 university athletes, 5 females, 4 males, aged 18–26, from three team sports (soccer, rugby, and cheerleading). Main Results First, we identified 24 factors divided into three intra-personal (Attitudes & Behaviors; Concussion Knowledge; Subjective Injury Severity) and two extra-personal categories (Socio-Cultural Pressures; Contextual Incentives) as determinants of concussion disclosure. Second, anchored around the core category Fear, we integrated these factors and categories into a grounded theory of concussion disclosure named Concussion Disclosure Theory (CDT). CDT posits that disclosure decisions are determined by the relative weight of two competing aversions: presence-aversion and absence-aversion. The factors identified seem to influence disclosure by generating one or both types of aversion. Our CDT also describes how most athletes adopt a non-disclosure bias strategy following a first concussion. Conclusions Our work highlights the benefits of using qualitative methods to study concussion disclosure and the importance of systematically investigating both intra- and extra-personal factors. Decision-making mechanisms proposed by our CDT can be used to generate future hypotheses and help design interventions aimed at promoting concussion disclosure. For example, it suggests that educational interventions designed to generate more presence-aversion could reverse the non-disclosure bias and promote concussion disclosure. Future research should validate the components of our CDT and their mechanisms of influence on the disclosure decision-making process in more diverse populations.

Our goal was to evaluate persisting deficits in gait and executive functioning in asymptomatic athletes with a history of concussion using a novel approach combining a dual-task paradigm and post-exercise exertion. Thirty-eight athletes aged 17 to 25 years old participated in the study, including 18 with a history of concussion. The dual-task paradigm required walking continuously at a predetermined self-paced target speed of 6.5 km/h while executing a complex switch task. Athletes completed two conditions, each on separate days: (1) dual task alone and (2) dual task following 20 min of running on a non-motorized treadmill. The statistical analyses revealed a significant reduction in gait speed exclusively for athletes with a history of concussion and only following the post-exercise condition (p = 0.008). These findings suggest that although asymptomatic concussed athletes maintain a cognitive performance comparable to non-concussed athletes, this appears to be achieved at the expense of gait speed. Our results underscore the importance of incorporating gait assessments and post-exercise exertion into concussion evaluation protocols in both research and clinical settings.

Objective 1) Examine the impact of a sports concussion on heart rate variability (HRV) metrics at rest and during a cognitive effort in athletes deemed recovered per usual care; 2) Investigate the association between HRV alterations and cognition. Design Observational study. Setting Laboratory. Participants University athletes who successfully completed step 4 of Zurich return-to-play protocol but had not begun step 5 and teammate controls with no concussion history. History of cardiovascular and neurological disorder, or psychotropic medication/substance use were exclusionary. Outcome Measures Heart rate and respiration data were recorded during a 5-min rest, followed by a color-shape switch cognitive task with a chest-strap. HRV was analyzed for the last 2-min of rest and 2-min of cognitive effort for time- (SD of NN intervals; root mean square of successive differences) and frequency-domain (low and high frequency), and non-linear approximate entropy. Main Results 11 concussed [M(SD)age=22.55(2.58); 6 females; M(SD)days=14.64(7.35) post-concussion] and 14 control athletes [M(SD)age=20.57(1.83); 8 females] were included. Heart rate and respiration did not differ between-group, ps>0.648. A 2(Group)×2(Condition) interaction was found for entropy, F(1,23)=5.16, p=0.033, η2=0.183, with concussion group exhibiting greater entropy [M(SD)=0.80(0.09)] during cognitive effort relative to rest [M(SD)=0.71(0.10)], p=0.001, Hedge's G=1.012[95%CI=0.375,1.626]. The control group did not exhibit this pattern (p=0.286). No other HRV metrics were significant, ps>0.217. Entropy at rest or during cognitive effort were not predictors of accuracy or reaction time on the switch task, ps>0.240. Conclusions This preliminary data suggests autonomic dysfunction emerges during cognitive effort even when participants are asymptomatic and cleared to return to play.

Objective To explore the psychological readiness to return to performance following a concussion through the perspectives of three key sports actors: athletes, coaches, and mental performance consultants. Design Qualitative research using interpretative phenomenological epistemology, underpinned by relativist ontology. Setting Semi-structured interviews. Participants 18 athletes (9 females; Mdnage=22.5, IQR=4.2 years), 10 coaches (2 females, Mdnage=37.5, IQR=16.2 years), and 11 mental performance consultants (9 females; Mdnage=32.0, IQR=8.0 years) competing or working for the university, provincial, or national level in a variety of individual or team sports. All athletes had suffered at least one concussion in the past two years, had fully recovered from it, and had returned to sport competition at the time of the interview. Coaches and mental performance consultants had all worked with at least one athlete who met those same criteria. Main Results Confidence, control, and commitment emerged as main factors for psychological readiness to return to performance following a concussion. These factors are not fixed, rather they are evolving across three milestones of psychological readiness: recovery, return to sport, return to performance. The data enable the generation of a model and guidelines for the Progressive Psychological Readiness to Return to Performance After a Concussion. Conclusions Thus far, return to sport protocols have mainly considered physical readiness while disregarding psychological readiness. Our work highlights the importance of psychological progression that mirrors physical progression to promote optimal readiness to return to performance following a concussion. Future research should create and validate protocols aimed at promoting confidence, control, and commitment.

Most of the research investigating sports concussion (SC) disclosure has been conducted using questionnaires with a pre-determined set of questions. Hence, significant gaps remain in our understanding of which factors weight in the decision-making process underlying SC disclosure and how they contribute to it. This present study aims to fill some of these gaps using qualitative methods to identify intrapersonal determinants of SC disclosure and describe their influence on an athlete's decision-making process. Our results are based on in-depth, semistructured interviews (range, 56-79 min; total = 587 min) with 9 university athletes (5 females, 4 males) from three team sports (soccer, rugby, and cheerleading). Using constant comparative analysis guided by Straussian grounded theory, we identified 13 concepts, across three major intrapersonal categories (i.e., attitudes and behaviors; concussion knowledge; and subjective evaluation of the concussion), contributing to SC disclosure, including novel determinants such as prioritization of athletic versus intellectual activities and maturity level. Our results suggest that a comparison between experiential knowledge and severity of the injury plays a major role in determining an athlete's disclosure behaviors. Athletes with a history of concussion seem to adopt a non-disclosure default strategy and are inclined to disclose their concussion symptoms only if they judge their current concussion to be worse than their previous most severe injury. Other concepts identified appear to contribute to the decisional process by modulating the adoption of this non-disclosure default strategy. Our work highlights the benefits and necessity of using qualitative methods to study the decision-making process underlying concussion disclosure.

ABSTRACT Introduction/Purpose This meta-analysis aimed to investigate the long-term (3+ months) consequences of concussion across cognitive domains (processing speed, memory, attention, and executive functions) and subdomains in young adult athletes (university, professional, or recreational). Methods Six databases (EMBASE, PubMed, PsycINFO, SPORTDiscus, Web of Science, and Cochrane List of Registered Trials) were searched for studies that compared cognitive performance between athletes with a history of concussion (HOC) and control athletes who never sustained a brain injury. Thus, the analyses were restricted to the studies investigating sports concussions. Results Nineteen studies, including 20 independent experiments with 1514 participants (521 HOC athletes, 1184 controls), were identified. Athletes from the HOC group sustained an average of 2.40 ± 0.99 concussions, with an average of 29.88 ± 19.26 months after injury. Importantly, all HOC athletes were tested at least 3 months after their most recent concussion. The results indicated significant medium-to-large group differences (Hedges’ g = 0.55–1.03; P values < 0.0001) for executive functions subdomains on both standardized clinical tests and screening tools. Specifically, HOC athletes had lower cognitive performance relative to controls in strategy generation/regulation, verbal set-shifting and interference management on standardized clinical tests (Regensburger verbal fluency S words and G/R words), and response inhibition (ImPACT Impulse Control composite) and prospective working memory (Cogstate two-back task) on screening tools. Encoding phase of visual memory (Brief Visuospatial Memory Test) on standardized clinical tests approached significance (Hedges’ g = 0.40; P values = 0.08). Conclusions The current findings provide a preliminary guideline to clinicians for the assessment of cognition in HOC athletes and inform future guidelines on common data elements of sport-related concussions.

Primary Objective: To determine whether a physical exercise protocol could reveal persistent cognitive alterations in university athletes with a history of concussion (HOC). Thirty-four HOC and 34 controls participated in this study. Research Design: Cross-sectional. Methods and Procedures: The exercise protocol consisted of a 20-min bout on a stationary bike at 80% of the theoretical maximal heart rate. Before and after the exercise, participants performed a computerized switch task designed specifically to recruit executive functions. Group x Condition (pre- and post-exercise) repeated measures of ANCOVAs for accuracy, reaction time, and inverse efficiency score on the switch task were conducted. Chi-square tests were run to determine if the proportion of HOC and controls who underperformed (at least 2SD lower than the control group's average score) at rest and post-exercise were similar. Whilst no interaction or main effects were found with ANCOVAs, significantly more HOC athletes (21%) underperformed following exercise than at rest (3%) on the switch task, p = .02. The current results indicate that an acute bout of exercise can reveal persistent alterations that are not present at rest in the protracted phase of concussion. They also highlight the importance of considering inter-individual differences in recovery trajectories.

Background. Athletes with specific learning disorder (LD) tend to score lower on neuropsychological tests and are at increased risk of personal injury than their counterparts without such disorders. Using a retrospective historical and prospective design, we examined whether adult athletes with LD, the most prevalent of neurodevelopmental disorders, experience greater chances of past and future concussions than their counterparts without LD. We expected to find that young athletes with LD would show greater risk of past (historical) and future (prospective) cerebral concussions. Methods. Participants (95 men and 53 women aged 18 to 25 years) were recruited from university sports teams and followed during an entire season. Of these, 38 participants had a history of LD and 101 had a history of at least 1 concussion (72 males, 29 females) at the preseason baseline. One-third experienced a new concussion. Data analytic procedures include inferential cross-tabulations. Results. Athletes with LD were twice more likely to have a concussion history at baseline and to have a history of multiple concussions than athletes without LD; 95% CI = [0.86, 4.92] and [0.77, 3.40], respectively. Athletes with LD were twice more likely to incur a new concussion than those without LD; 95% CI = [0.86, 4.92]. Conclusions. Adult athletes with LD experience greater chances of previous and future concussions compared with counterparts without LD. Preventive practices regarding individuals with neurodevelopmental disorders may not only prevent the biopsychosocial consequences of brain trauma for the individual, but also represent a cost-effective public health measure.

The human brain is highly cross-modal, and sensory information may affect a wide range of behaviors. In particular, there is evidence that auditory functions are implicated in oculomotor behaviors. Considering this apparent auditory-oculomotor link, one might wonder how the loss of auditory input from birth might have an influence on these motor behaviors. Eye movement tracking enables to extract several components, including saccades and smooth pursuit. One study suggested that deafness can alter saccades processing. Oculomotor behaviors have not been examined further in the deaf. The main goal of this study was to examine smooth pursuit following deafness. A pursuit task paradigm was used in this experiment. Participants were instructed to move their eyes to follow a target as it moved. The target movements have a possibility of four different trajectories (horizontal, vertical, elliptic clockwise, and elliptic counter-clockwise). Results indicate a significant reduction in the ability to track a target in both elliptical conditions showing that more complex motion processing differs in deaf individuals. The data also revealed significantly more saccades per trial in the vertical, anti-clockwise, and, to a lesser extent, the clockwise elliptic condition. This suggests that auditory deprivation from birth leads to altered overt oculomotor behaviors.

In the context of return to play assessment following a sports concussion, athletes may have to complete a cognitive task several times within days. The current longitudinal study aimed to examine the practice effect associated with the serial administration of the switch task. We hypothesized that the practice effect would be the greatest between the first and second assessments and that a plateau would be obtained by the third assessment. Forty healthy university students completed the switch task four times at an interval of 48-hour, with half of them doing version A on all visits (AA group), while the others alternated between A and B every other assessment (AB group). For response accuracy, performance generally improved from V1 to V2, and from V2 to V3 (ps ≤.001), irrespective of group. For reaction time, a significant interaction of Visit × Group was observed. Specifically, AA group performance improved from V1 to V2, and from V2 to V3, while the AB group only improved from V2 to V3 (ps ≤.01). Performance improved over the first three assessments and stabilized with no statistically significant change between the third and fourth testing sessions. Although the use of an alternative version has helped reduce the practice effect, it did not help in eliminating it. The current results highlight the need for further examination of the practice effect and its implication in clinical decision-making. Clinicians working in the sports concussion field must take the practice effect into account when they use the switch task for serial testing.

ABSTRACT Introduction The decision to clear an athlete to return to play (RTP) after a concussion is critical given the potential consequences of premature RTP. Accordingly, this study aimed to investigate more sensitive ways to assess readiness for RTP. We examined postexercise cognitive assessment in recently concussed and asymptomatic university athletes who were cleared to RTP. Methods Forty recently concussed athletes and 40 control athletes without a history of concussion participated in the study. Athletes completed a switch task preexercise and postexercise (20 min on an ergometer at 80% maximal heart rate). A series of one-way ANOVA were performed to compare accuracy and response time between the concussion and the control groups on the switch task. Given that the clinical recovery of the participants in the concussion group could be heterogeneous, we also ran χ 2 tests to identify the presence of subgroups. Specifically, we aimed to determine whether a group difference existed in the proportion of concussed participants who underperformed. Results No difference between the concussion and control groups was observed for reaction time. However, a significant group difference was found for accuracy, with athletes from the concussion group exhibiting lower accuracy relative to the control group. Irrespective of condition (rest, postexercise), up to 30% of athletes from the concussion group were 2 SD lower when compared with the control group's average score. A third of the athletes only exhibited deficits after exercise. Conclusions Our results highlight the importance of considering interindividual differences in recovery trajectories. Although asymptomatic and cleared to RTP, an important portion of athletes had not completely recovered from their concussion. Fortunately, these athletes can be readily identified by using sensitive cognitive tests administered after a moderate-to-vigorous exercise.

The current study aims to examine the psychometric properties of a color-shape version of the switch task. In Study 1, 128 participants completed a battery of standardized measures of executive functions (EFs) as well as the switch task to determine the construct validity of three traditionally computed costs (global, switch, and mixing) and primary variables (accuracy [ACC], reaction time [RT], and inverse efficiency score [IES] of the heterogeneous condition). In Study 2, 48 participants completed the task twice, seven days apart, to evaluate its short-term test-retest reliability. Results do not support the construct validity and the test-retest reliability of switch and mixing costs. The overall higher psychometric properties of the global costs (RT and IES), and primary variables (Hetero RT and IES) suggest that they may be useful measures for clinicians to assess EFs. The latter variables show evidence of convergent validity with standardized measures of EFs and good test-rest reliability (ICC ≥ .68).

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.