Where is the research on sport-related concussion in Olympic athletes? A descriptive report and assessment of the impact of access to multidisciplinary care on recovery.

OBJECTIVES: This cohort study reported descriptive statistics in athletes engaged in Summer and Winter Olympic sports who sustained a sport-related concussion (SRC) and assessed the impact of access to multidisciplinary care and injury modifiers on recovery. METHODS: 133 athletes formed two subgroups treated in a Canadian sport institute medical clinic: earlier (≤7 days) and late (≥8 days) access. Descriptive sample characteristics were reported and unrestricted return to sport (RTS) was evaluated based on access groups as well as injury modifiers. Correlations were assessed between time to RTS, history of concussions, the number of specialist consults and initial symptoms. RESULTS: 160 SRC (median age 19.1 years; female=86 (54%); male=74 (46%)) were observed with a median (IQR) RTS duration of 34.0 (21.0-63.0) days. Median days to care access was different in the early (1; nSRC=77) and late (20; nSRC=83) groups, resulting in median (IQR) RTS duration of 26.0 (17.0-38.5) and 45.0 (27.5-84.5) days, respectively (p<0.001). Initial symptoms displayed a meaningful correlation with prognosis in this study (p<0.05), and female athletes (52 days (95% CI 42 to 101)) had longer recovery trajectories than male athletes (39 days (95% CI 31 to 65)) in the late access group (p<0.05). CONCLUSIONS: Olympic athletes in this cohort experienced an RTS time frame of about a month, partly due to limited access to multidisciplinary care and resources. Earlier access to care shortened the RTS delay. Greater initial symptoms and female sex in the late access group were meaningful modifiers of a longer RTS.

Sport-Specific Agility and Change of Direction in Water Polo: The Reliability and Validity of Two Newly Developed Tests.

ABSTRACT: Dong, L, Paradelo, D, Delorme, A, Oliveira, J, Parillo, B, Croteau, F, Romeas, T, Dubé, E, Bieuzen, F, Billaut, F, and Berryman, N. Sport-specific agility and change of direction in water polo: The reliability and validity of two newly developed tests. J Strength Cond Res 35(12S): S111-S118, 2021-There is a gap in water-based agility testing that considers both the change-of-direction (COD) and perceptive-reactive components of agility. This study sought to develop easily implementable, sport-specific in-water agility tests for water polo and to verify the reliability and validity of these new tests: the in-water Stop and Go (SG) and Jump and Go (JG). Female water polo athletes at the Senior (n = 12, age = 22.1 ± 2.1 years), Junior (n = 19, age = 18.5 ± 1.0 years), and Youth (n = 11, age = 16.5 ± 0.8 years) national levels performed 3 trials of each of the SG, JG, and the existing Functional Test for Agility Performance (FTAP). Senior athletes performed an additional experimental session to assess reliability parameters. Relative reliability for agility and COD versions of the SG and JG was high or very high (intraclass correlation coefficient [ICC] = 0.76-0.95). For construct validity analyses, significant between-group differences for each of the new tests (p < 0.05) were found. In contrast, the FTAP was moderately reliable (ICC = 0.57) and was unsuccessful in discriminating between playing levels. Considering the favorable metrological properties of the SG and JG, their fidelity to in-game demands, and their accessible setups, these new tests represent viable options to implement at grassroots and elite levels for the assessment and training of water polo-specific agility.

A temporal quantitative analysis of visuomotor behavior during four twisting somersaults in elite and sub-elite trampolinists.

Vision has previously been correlated with performance in acrobatic sports, highlighting visuomotor expertise adaptations. However, we still poorly understand the visuomotor strategies athletes use while executing twisting somersaults, even though this knowledge might be helpful for skill development. Thus, the present study sought to identify the differences in gaze behavior between elite and sub-elite trampolinists during the execution of four acrobatics of increasing difficulty. Seventeen inertial measurement units and a wearable eye-tracker were used to record the body and gaze kinematics of 17 trampolinists (8 elites, 9 sub-elites). Six typical metrics were analyzed using a mixed analysis of variance (ANOVA) with the Expertise as inter-subject and the Acrobatics as intra-subject factors. To complement this analysis, advanced temporal eye-tracking metrics are reported, such as the dwell time on areas of interest, the scan path on the trampoline bed, the temporal evolution of the gaze orientation endpoint (SPGO), and the time spent executing specific neck and eye strategies. A significant main effect of Expertise was only evidenced in one of the typical metrics, where elite athletes exhibited a higher number of fixations compared to sub-elites (p = 0.033). Significant main effects of Acrobatics were observed on all metrics (p < 0.05), revealing that gaze strategies are task-dependent in trampolining. The recordings of eyes and neck movements performed in this study confirmed the use of "spotting" at the beginning and end of the acrobatics. They also revealed a unique sport-specific visual strategy that we termed as self-motion detection. This strategy consists of not moving the eyes during fast head rotations, a strategy mainly used by trampolinists during the twisting phase. This study proposes a detailed exploration of trampolinists' gaze behavior in highly realistic settings and a temporal description of the visuomotor strategies to enhance understanding of perception-action interactions during the execution of twisting somersaults.

Multiple domain-general assessments of cognitive functions in elite athletes: Contrasting evidence for the influence of expertise, sport type and sex.

Converging evidence has shown that domain-general cognitive abilities, especially executive functions (EF), tend to be superior in sport experts. However, recent studies have questioned this cognitive advantage and found inconsistent findings when comparing sport type and sex. This study aimed to compare the impact of sport expertise, sport type, and sex on various domains of cognitive functions. Two hundred and thirty elite athletes (nFemale = 124, nMale = 106) representing three sport categories (Team [n = 91], Precision-skill dependent [n = 63], and Speed-strength [n = 76] sports) were assessed using a computerized neuropsychological test battery including tests of EF (working memory, inhibition, cognitive flexibility and planning), as well as tests of selective and sustained attention. T-scores and raw values were used to analyze performance through t-tests and ANCOVA with age as covariate. Athletes demonstrated better performance than the normative mean on 5 out of 11 cognitive test variables (p < 0.005). However, their performance fell within the average range when considering the results along a normative scale, except for sustained attention and working memory where they performed just above average (<1 SD). There was a significant main effect of sport category on only one EF variable (p = 0.003). Males performed significantly faster than females on motor reaction time measures of attention and inhibition (all p < 0.001). In this study, the 'expert advantage' on domain-general cognitive tests was less prominent when utilizing a normative scale and controlling for age or speed-accuracy trade-offs, except for sustained attention and working-memory. Cognitive functions did not appear to differ meaningfully based on athletes' sport type or sex.

Exploring the effects of 3D-360°VR and 2D viewing modes on gaze behavior, head excursion, and workload during a boxing specific anticipation task.

Introduction: Recent evidence has started to demonstrate that 360°VR, a type of VR that immerses a user within a 360° video, has advantages over two-dimensional (2D) video displays in the context of perceptual-cognitive evaluation and training. However, there is currently a lack of empirical evidence to explain how perceptual-cognitive strategies differ between these two paradigms when performing sports-related tasks. Thus, the objective of this study was to examine and compare the impact of different viewing conditions (e.g., 3D-360°VR and 2D video displays), on gaze behavior and head excursions in a boxing-specific anticipatory task. A secondary objective was to assess the workload associated with each viewing mode, including the level of presence experienced. Thirdly, an exploratory analysis was conducted to evaluate any potential sex differences. Methods: Thirty-two novice participants (16 females) were recruited for this study. A total of 24 single-punch sequences were randomly presented using a standalone VR headset (Pico Neo 3 Pro Eye), with two different viewing modes: 3D-360°VR and 2D. Participants were instructed to respond to the punches with appropriate motor actions, aiming to avoid punches. Gaze behavior was recorded using a Tobii eyetracker embedded in the VR headset. Workload and presence were measured with the SIM-TLX questionnaire. Fixation duration, number of fixations, saccades, search rate and head excursions (roll, pitch, yaw) were analyzed using linear mixed models. Results: The results revealed significant shorter fixation durations and more head excursions (roll, pitch) in 3D-360°VR, compared to the 2D viewing mode (ps < 0.05). The sense of presence was found to be much higher in the 3D-360°VR viewing mode (p < 0.05). No sex differences were observed. These results demonstrate that 360°VR elicited shorter fixation durations but mostly greater head excursions and immersion compared to a 2D projection in the context of a boxing-specific task. Discussion: These findings contribute to the understanding of previous evidence supporting the possible advantages of using 360°VR over 2D for perceptual-cognitive evaluation and training purposes. Further validation studies that compare behaviors and performance in 360°VR with those in the real-world will be needed.

Dynamic Visual Stimulations Produced in a Controlled Virtual Reality Environment Reveals Long-Lasting Postural Deficits in Children With Mild Traumatic Brain Injury.

Motor control deficits outlasting self-reported symptoms are often reported following mild traumatic brain injury (mTBI). The exact duration and nature of these deficits remains unknown. The current study aimed to compare postural responses to static or dynamic virtual visual inputs and during standard clinical tests of balance in 38 children between 9 and 18 years-of-age, at 2 weeks, 3 and 12 months post-concussion. Body sway amplitude (BSA) and postural instability (vRMS) were measured in a 3D virtual reality (VR) tunnel (i.e., optic flow) moving in the antero-posterior direction in different conditions. Measures derived from standard clinical balance evaluations (BOT-2, Timed tasks) and post-concussion symptoms (PCSS-R) were also assessed. Results were compared to those of 38 healthy non-injured children following a similar testing schedule and matched according to age, gender, and premorbid level of physical activity. Results highlighted greater postural response with BSA and vRMS measures at 3 months post-mTBI, but not at 12 months when compared to controls, whereas no differences were observed in post-concussion symptoms between mTBI and controls at 3 and 12 months. These deficits were specifically identified using measures of postural response in reaction to 3D dynamic visual inputs in the VR paradigm, while items from the BOT-2 and the 3 timed tasks did not reveal deficits at any of the test sessions. PCSS-R scores correlated between sessions and with the most challenging condition of the BOT-2 and as well as with the timed tasks, but not with BSA and vRMS. Scores obtained in the most challenging conditions of clinical balance tests also correlated weakly with BSA and vRMS measures in the dynamic conditions. These preliminary findings suggest that using 3D dynamic visual inputs such as optic flow in a controlled VR environment could help detect subtle postural impairments and inspire the development of clinical tools to guide rehabilitation and return to play recommendations.

Combining 3D-MOT With Sport Decision-Making for Perceptual-Cognitive Training in Virtual Reality.

This study introduces a virtual life-sized perceptual-cognitive training paradigm that combines three-dimensional multiple object tracking (3D-MOT) with motor (Experiment 1) or perceptual (Experiment 2) sport decision-making tasks. We sought to assess the impact of training on task performance and determine optimal training conditions for improvement and learning. Fifty-seven participants were randomly assigned to one of four training conditions (isolated 3D-MOT, 3D-MOT combined with a decision-making task, consolidated 3D-MOT later combined with a decision-making task, and isolated decision-making task). We evaluated task performance using speed thresholds, success rate (%), and reaction time (s). Findings were that the dual-task paradigm was associated with performance beyond chance level on both 3D-MOT and decision-making tasks despite an important dual-task cost. Interestingly, the results seemed to favor consolidated 3D-MOT training over simultaneous 3D-MOT training when combined with a motor decision-making task but not when combined with a perceptual decision-making task. The number of shared attentional resources in the nature of the additional task (i.e., perceptual or motor decision-making) seems to be key in interpreting the dual-task interference. These findings must be considered when designing representative multitask perceptual-cognitive training.

The combined impact of a perceptual-cognitive task and neuromuscular fatigue on knee biomechanics during landing.

BACKGROUND: A large majority of anterior cruciate ligament (ACL) injuries are non-contact, most often occurring during a landing or change of direction. Recent research indicates that cognitive factors may be involved in non-contact ACL injuries. The aim of this study was to determine if a game-situation perceptual-cognitive load leads to altered landing kinematics in physically fatigued female athletes. METHODS: Nineteen female recreational athletes were recruited to perform a series of jumping and landing trials. In a first phase, eight trials were performed in an isolated condition and eight were performed while participants performed a perceptual-cognitive task. Before a second identical phase, participants underwent a muscular fatigue protocol. Knee-joint kinematics were recorded and compared between conditions using paired t-tests. RESULTS: Muscle fatigue led to statistically significant increases in peak knee abduction and peak internal knee rotation as well as a decrease in maximum knee flexion, when comparing conditions without the perceptual-cognitive task. The perceptual-cognitive task had no statistically significant effect on any knee rotations, either pre- or post-fatigue. However, a subgroup of 12 athletes showed a significant increase in knee abduction in the presence of the perceptual-cognitive task, only in the fatigued condition. CONCLUSION: A perceptual-cognitive task combined with muscle fatigue alters knee kinematics of landing for a subset of recreational athletes, potentially increasing the risk of ACL rupture. Further studies are necessary to confirm this finding and to identify characteristics of at-risk individuals to target them for injury prevention protocols.

Perceptual-cognitive three-dimensional multiple-object tracking task can help the monitoring of sport-related concussion.

OBJECTIVES: While the rate of sport-related concussion is increasing, more effective tools are needed to help monitor the diagnosis and return to play of athletes. The three-dimensional multiple-object tracking (3D-MOT) exercise is a perceptual-cognitive task that has shown predictive power towards the dynamic requirements of real-world activities such as sport. This study introduced the use of the 3D-MOT task, along with the Standardized Assessment of Concussion (SAC) and Modified Balance Error Scoring System (M-BESS) tests, for diagnosis and return to play in professional sports. METHODS: Fifty-nine professional athletes were tested with the 3D-MOT, SAC and M-BESS tests at 48 hours following the injury. The same measures were employed to evaluate the return to play following the standard concussion management protocol. The SAC and M-BESS tests were also performed in pre-season (baseline) in 32 out of the 59 athletes. RESULTS: The injured athletes exhibited poor performance on 3D-MOT at 48 hours post injury compared with return to play (p<0.001) as well as compared with healthy professionals' performance scores (p<0.001). Importantly, learning rate, which participants are thought to have an expert advantage on this perceptual-cognitive task, was totally disrupted at 48 hours post injury compared with healthy professionals (p<0.001). The 3D-MOT performance was also correlated to the total number of symptoms (p=0.020), SAC (p=0.031) and M-BESS (p=0.004) scores at 48 hours. Not surprisingly, SAC and M-BESS tests' usefulness for monitoring concussion was found to be weak, particularly when test performance following the injury was compared to baseline (p=0.056 and 0.349 for SAC and M-BESS, respectively). CONCLUSION: 3D-MOT could help monitor sport-related concussion in professional athletes. The discussion also covers the critical importance of perceptual-cognitive assessment following concussion in the athletic population.

Enhancing data visualisation to capture the simulator sickness phenomenon: On the usefulness of radar charts.

The data presented in this article are related to the research article entitled "The use of transdermal scopolamine to solve methodological issues raised by gender differences in susceptibility to simulator sickness" (Chaumillon et al., 2017) [1]. In an outstanding first demonstration, Kennedy et al. [2] showed that the Simulator Sickness Questionnaire (SSQ) is an appropriate tool to suit the purposes of characterizing motion sickness experienced in virtual environments. This questionnaire has since been used in many scientific studies. Recently, Balk et al. [3] suggested that the proposed segregation of SSQ scores into three subclasses of symptoms might limit the accuracy of simulator sickness assessment. These authors performed a factor analysis based on SSQ scores obtained from nine studies on driving simulators. Although their factor analysis resulted in the same three orthogonal classes of symptoms as Kennedy et al. [2], unlike this pioneering study, no items were attributed to more than one factor and five items were not attributed to any class of symptoms. As a result, they claimed that an exploration of each item score should give additional cues on individual profiles. To gain a better characterization of such item-by-item exploration, data utilised in this research are shown using a radar chart visualisation.

Soccer athletes are superior to non-athletes at perceiving soccer-specific and non-sport specific human biological motion.

Recent studies have shown that athletes' domain specific perceptual-cognitive expertise can transfer to everyday tasks. Here we assessed the perceptual-cognitive expertise of athletes and non-athletes using sport specific and non-sport specific biological motion perception (BMP) tasks. Using a virtual environment, university-level soccer players and university students' non-athletes were asked to perceive the direction of a point-light walker and to predict the trajectory of a masked-ball during a point-light soccer kick. Angles of presentation were varied for orientation (upright, inverted) and distance (2 m, 4 m, 16 m). Accuracy and reaction time were measured to assess observers' performance. The results highlighted athletes' superior ability compared to non-athletes to accurately predict the trajectory of a masked soccer ball presented at 2 m (reaction time), 4 m (accuracy and reaction time), and 16 m (accuracy) of distance. More interestingly, experts also displayed greater performance compared to non-athletes throughout the more fundamental and general point-light walker direction task presented at 2 m (reaction time), 4 m (accuracy and reaction time), and 16 m (reaction time) of distance. In addition, athletes showed a better performance throughout inverted conditions in the walker (reaction time) and soccer kick (accuracy and reaction time) tasks. This implies that during human BMP, athletes demonstrate an advantage for recognizing body kinematics that goes beyond sport specific actions.

Selective serotonin reuptake inhibitors potentiate the rapid antidepressant-like effects of serotonin4 receptor agonists in the rat.

BACKGROUND: We have recently reported that serotonin(4) (5-HT(4)) receptor agonists have a promising potential as fast-acting antidepressants. Here, we assess the extent to which this property may be optimized by the concomitant use of conventional antidepressants. METHODOLOGY/PRINCIPAL FINDINGS: We found that, in acute conditions, the 5-HT(4) agonist prucalopride was able to counteract the inhibitory effect of the selective serotonin reuptake inhibitors (SSRI) fluvoxamine and citalopram on 5-HT neuron impulse flow, in Dorsal Raphé Nucleus (DRN) cells selected for their high (>1.8 Hz) basal discharge. The co-administration of both prucalopride and RS 67333 with citalopram for 3 days elicited an enhancement of DRN 5-HT neuron average firing rate, very similar to what was observed with either 5-HT(4) agonist alone. At the postsynaptic level, this translated into the manifestation of a tonus on hippocampal postsynaptic 5-HT(1A) receptors, that was two to three times stronger when the 5-HT(4) agonist was combined with citalopram. Similarly, co-administration of citalopram synergistically potentiated the enhancing effect of RS 67333 on CREB protein phosphorylation within the hippocampus. Finally, in the Forced Swimming Test, the combination of RS 67333 with various SSRIs (fluvoxamine, citalopram and fluoxetine) was more effective to reduce time of immobility than the separate administration of each compound. CONCLUSIONS/SIGNIFICANCE: These findings strongly suggest that the adjunction of an SSRI to a 5-HT(4) agonist may help to optimize the fast-acting antidepressant efficacy of the latter.

Simultaneous anhedonia and exaggerated locomotor activation in an animal model of depression.

RATIONALE: Anhedonia, or hyposensitivity to normally pleasurable stimuli, is a cardinal symptom of depression. As such, reward circuitry may comprise a substrate with relevance to this symptom of depression. OBJECTIVES: Our aim was to characterize in the rat changes in the rewarding properties of a pharmacological and a natural stimulus following olfactory bulbectomy (OBX), a pre-clinical animal model of depression. METHODS: We measured amphetamine enhancement of brain stimulation reward, changes in sucrose intake, as well as striatal cAMP response element binding protein (CREB) activity, a molecular index previously associated with depressant-like behavior. Moreover, since alteration of psychomotor activity is also a common symptom of depression, and psychostimulant reward and locomotion are thought to share common neurobiology, we used the same treatment schedule of amphetamine to probe for changes in locomotion. RESULTS: Our findings show that OBX produces a behavioral phenotype characterized by both anhedonia and exaggerated locomotor activation. Thus, we observed a blunted response to the rewarding properties of amphetamine (1 mg/kg, 21 days post-lesion), a long-lasting reduction in sucrose intake and increased striatal CREB activity. In addition, the same dose of amphetamine, at a coincident time post-lesion, triggered an exaggerated response to its locomotor-stimulant actions. CONCLUSIONS: These paradoxical findings are not consistent with the notion that reward and locomotion are mediated by a common substrate; this dissociation may be useful in modeling psychiatric disorders such as mixed depressive states. In addition, our findings suggest that central reward circuitry may constitute a possible target for rationally designed therapeutics for depression.