The Effects of Anticipation and Visual and Sensory Performance on Concussion Risk in Sport: A Review

The Acute Effects of Ball Pressure on Anticipation Timing Following a Series of Purposeful Headers in Adult Football (Soccer) Players

The purpose of this study is to investigate the acute effects of ball pressure on anticipation timing following a series of purposeful headers in adult football (soccer) players. There is evidence to suggest acute neurophysiological changes to the brain following purposeful heading; this may lead to altered anticipation timing as a result, potentially having future safety implications for players. A repeated measures crossover design was used. Seventeen participants aged between 20 and 30 years performed (i) 20 rotational headers with a lower-pressure match ball (58.6 kPa; 8.5 psi), (ii) 20 rotational headers with a higher-pressure match ball (103.4 kPa; 15 psi), or (iii) 20 non-headers (kicks) as a control each on separate days. The effect of ball pressure on anticipation timing accuracy, measured as absolute, constant, and variable errors, was assessed before and immediately after each intervention session using an anticipation timing task. Differences between group means were compared using repeated measures ANOVA and linear mixed effects models, with p-values of <0.05 considered statistically significant. No significant differences in anticipation timing accuracy across interventions were detected between control, occluded, and non-occluded trials. This finding differs from the previous literature regarding the measurable, acute effects of purposeful heading. The anticipation timing task may lack sensitivity for detecting the effects of repeated heading on brain function.

Concussion history and virtual reality metrics predict core or lower extremity injury occurrence among high school athletes

Introduction

A history of concussion is recognized as a risk factor for musculoskeletal injury, which is likely associated with physiological effects that warrant better understanding. This study aimed to assess the potential of measurements obtained from an immersive virtual reality (VR) test to identify a subtle perceptual-motor impairment that may be prospectively associated with the occurrence of a core or lower extremity sprain or strain.

Methods

A cohort of 68 high school athletes (41 female soccer players and 27 male football players) provided survey responses and completed an immersive VR test several days prior to the initiation of preseason practice sessions. Measurements of eye, neck, arm, and whole-body displacements were obtained during 40 successive lunging/reaching responses to visual stimuli moving horizontally across the VR headset display. Injury occurrences were electronically documented from the initial preseason practice session to the final game of the season.

Results

A statistically significant and intrinsically credible two-factor prediction model for core or lower extremity injury occurrence included an interaction between female sex and a self-reported history of two or more concussions, along with slow response time (RT) for arm reach (OR = 4.67; 95% CI, 1.51-14.43). Follow-up analyses identified sex-specific cut points for arm reach RT associated with elevated injury risk, which were ≥1.385 s for females and ≥1.257 s for males.

Discussion

High school female soccer players who have sustained more than one concussion appear to be highly vulnerable to core or lower extremity sprain or strain, with the risk of injury compounded by a slow arm reach RT. Male football players as a group demonstrated significantly faster arm reach RT than that of female soccer players, but slow perceptual-motor RT for arm reach was also identified as a potentially important injury risk factor for male players. Immersive VR appears to provide precise measurements of behavioral performance characteristics that depend on brain processing efficiency. Given that the speed, accuracy, and consistency of perceptual-motor responses may be modifiable, future research should explore the potential benefits of VR training for reducing the risk of sport-related injuries.

Understanding elite rugby league players' experience of collision, effective contact coaching techniques, and player contact psychology: A focus group study

The current study performed a series of online focus groups to understand elite rugby league players' experiences of collision. Eighteen rugby league players comprising different playing positions from four teams were recruited to participate in a series of online focus groups, via the Microsoft Team's platform, facilitated by a moderator. Players were competing in Europe's elite rugby league competition, the European Super League (ESL), during the 2021 season. All focus group data were transcribed, coded and analysed using reflexive thematic analysis guide to ensure robust exploring, interpreting and reporting through pattern-based analysis. The findings are split into five key themes: 1) the three-man tackle - the perceived optimal defensive strategy with simultaneous contact, 2) not all collisions are the same; matchplay events change the collision intensity, 3) bracing and blindsiding - two factors that influence experiences of collision and concussion, 4) coaching philosophies and orientations, 5) psychological readiness for collision. Collision sports have an inherent risk of injury; however, in some players' subjective experiences, there are collision types that have a greater association with risk or intensity (blind-sided collisions or long closing distances). It is essential that future research comprehends the effects of these collision types and the further themes.

Adjusting to Changing Environments: Virtual Preseason SCAT5 Assessment in Canadian Male Youth Football Players

OBJECTIVE

To provide preseason reference scores for Canadian youth tackle football players on the Sport Concussion Assessment Tool 5 (SCAT5) and to examine whether age, concussion history, and self-reported medical diagnoses are associated with SCAT5 subcomponent performance.

DESIGN

Cross-sectional study.

SETTING

Calgary, Alberta.

PARTICIPANTS

Five hundred one male youth football players (ages 13-18 years) participating in the 2021 season.

ASSESSMENT OF RISK FACTORS

SCAT5 subcomponents were assessed by age group (13-14, 15-16, 17-18), concussion history (0, 1, 2+, and yes/no), and self-reported diagnoses (headache disorder, attention-deficit/hyperactive disorder, learning disability/dyslexia, and depression, anxiety, or other psychiatric disorder).

MAIN OUTCOME MEASURES

Virtual video administration (vs traditional in-person testing) of the SCAT5 was completed, and subcomponent scores included total number of symptoms (/22), symptom-severity score (/132), Standardized Assessment of Concussion [orientation (/5), immediate memory (/30), concentration (/5), delayed recall (/10)], and modified Balance Error Scoring System (/30). Kruskal-Wallis, one-way analysis of variance , Mann-Whitney U , or independent t tests were used to assess possible associations depending on number of groups and data normality.

RESULTS

Virtual SCAT5 assessment scores across all outcomes did not differ by age group or concussion history. The median number of symptoms and median symptom-severity score at baseline was 2, and 173 players (34.5%) reported no symptoms. Median total number of errors on the modified Balance Error Scoring System was 3. Participants with certain self-reported diagnoses (attention-deficit/hyperactive disorder, dyslexia) demonstrated poorer performance on some SCAT5 subcomponents (symptom reporting, Standardized Assessment of Concussion).

CONCLUSIONS

Baseline SCAT5 performance did not differ by age group or concussion history in male youth football players. Diagnoses of the self-reported disorders examined may be important considerations for interpretation of the SCAT5 assessment.

Subtle impairments of perceptual-motor function and well-being are detectable among military cadets and college athletes with self-reported history of concussion

Introduction

A lack of obvious long-term effects of concussion on standard clinical measures of behavioral performance capabilities does not preclude the existence of subtle neural processing impairments that appear to be linked to elevated risk for subsequent concussion occurrence, and which may be associated with greater susceptibility to progressive neurodegenerative processes. The purpose of this observational cohort study was to assess virtual reality motor response variability and survey responses as possible indicators of suboptimal brain function among military cadets and college athletes with self-reported history of concussion (HxC).

Methods

The cohort comprised 75 college students (20.7 ± 2.1 years): 39 Reserve Officer Training Corp (ROTC) military cadets (10 female), 16 football players, and 20 wrestlers; HxC self-reported by 20 (29.2 ± 27.1 months prior, range: 3-96). A virtual reality (VR) test involving 40 lunging/reaching responses to horizontally moving dots (filled/congruent: same direction; open/incongruent: opposite direction) was administered, along with the Sport Fitness and Wellness Index (SFWI) survey. VR Dispersion (standard deviation of 12 T-scores for neck, upper extremity, and lower extremity responses to congruent vs. incongruent stimuli originating from central vs. peripheral locations) and SFWI response patterns were the primary outcomes of interest.

Results

Logistic regression modeling of VR Dispersion (range: 1.5-21.8), SFWI (range: 44-100), and an interaction between them provided 81% HxC classification accuracy (Model χ ²[2] = 26.03, p < .001; Hosmer & Lemeshow χ ²[8] = 1.86, p = .967; Nagelkerke R ²= .427; Area Under Curve = .841, 95% CI: .734, .948). Binary modeling that included VR Dispersion ≥3.2 and SFWI ≤86 demonstrated 75% sensitivity and 86% specificity with both factors positive (Odds Ratio = 17.6, 95% CI: 5.0, 62.1).

Discussion/Conclusion

Detection of subtle indicators of altered brain processes that might otherwise remain unrecognized is clearly important for both short-term and long-term clinical management of concussion. Inconsistency among neck, upper extremity, and lower extremity responses to different types of moving visual stimuli, along with survey responses suggesting suboptimal well-being, merit further investigation as possible clinical indicators of persisting effects of concussion that might prove to be modifiable.

Spectacles with highly aspherical lenslets for myopia control do not change visual sensitivity in automated static perimetry

Purpose

Spectacle lenses with arrays of lenslets have gained popularity in myopia control due to their high efficacy, low impact on visual performance, and non-invasiveness. One of the questions regarding their impact on visual performance that still remain is that: do the lenslets impact visual field sensitivity? The current study aims to investigate the impact of wearing spectacle lenses with highly aspherical lenslets (HAL) on the visual field sensitivity.

Methods

An automated static perimetry test (Goldman perimeter target III) was employed to measure the detection sensitivity in the visual field. Targets were white light dots of various luminance levels and size 0.43°, randomly appearing at 76 locations within 30° eccentricity. Twenty-one adult subjects (age 23-61, spherical equivalent refractive error (SER) -8.75 D to +0.88 D) participated in the study. Sensitivities through two lenses, HAL and a single vision lens (SVL) as the control condition, were measured in random order.

Results

The mean sensitivity differences between HAL and SVL across the 76 tested locations ranged between -1.14 decibels (dB) and 1.28 dB. Only one location at 30° in the temporal visual field reached statistical significance (p < 0.00065) whereby the sensitivity increased by 1.1 dB with HAL. No significant correlation was found between the difference in sensitivity and age or SER. Such a difference is unlikely to be clinically relevant.

Conclusion

Compared to the SVL, the HAL did not change detection sensitivity to static targets in the whole visual field within 30° eccentricity.

Relationship between Aggressiveness, Self-Confidence, and Perceived Coach Support and Head Impact Exposure in Youth Football

This study evaluated head impact exposure (HIE) metrics in relation to individual-level determinants of HIE. Youth (n = 13) and high school (n = 21) football players were instrumented with the Head Impact Telemetry (HIT) system during one season. Players completed the Trait-Robustness of Self-Confidence Inventory (TROSCI), Sports Climate Questionnaire (SCQ), and Competitive Aggressiveness and Anger Scale (CAAS), measuring self-confidence, perceived coach support, and competitive aggressiveness, respectively. Relationships between HIE metrics (number of impacts, median and 95th percentile accelerations, and risk-weighted exposure (RWE)) and survey scores were evaluated using linear regression analysis. For middle school athletes, TROSCI scores were significantly negatively associated with the number of competition impacts and the mean number of impacts per player per competition. SCQ scores were significantly positively associated with median linear acceleration during practice. CAAS scores were not significantly associated with biomechanical metrics at either level of play. Perceived coach support and self-confidence might influence HIE among middle school football players. Football athletes' competitive aggressiveness may have less influence their HIE than other factors.

Development of a Novel Coaching Platform to Improve Tackle Technique in Youth Rugby Players: A Proof of Concept

Rugby union is a field sport that is played at amateur and professional levels by male and female players globally. One of the most prevalent injury risks associated with the sport involves tackle collisions with opposition players. This suggests that a targeted injury reduction strategy could focus on the tackle area in the game. In amateur rugby union, injuries to the head, face and shoulder are the most common injury sites in youth rugby playing populations. A suboptimal tackle technique may contribute to an increased injury risk in these populations. One proposed mitigation strategy to reduce tackle-related injuries in youth populations may be to increase tackle proficiency by coaching an effective tackle technique. The present study aimed to demonstrate a proof of concept for a tackle technique coaching platform using inertial measurement units (IMUs) and a bespoke mobile application developed for a mobile device (i.e., a mobile phone). The test battery provided a proof of concept for the primary objective of modelling the motion of a player in a tackle event. The prototype (bespoke mobile application) modelled the IMU in a 3D space and demonstrated the orientation during a tackle event. The participants simulated ten tackle events that were ten degrees above and ten degrees below the zero degree of approach, and these (unsafe tackles) were indicated by a red light on the mobile display unit. The parameters of ten degrees above and below the zero angle of approach were measured using an inclinometer mobile application. These tackle event simulations provided a real-time stream of data that displayed the angle of tackles on a mobile device. The novel coaching platform could therefore constitute part of an injury reduction strategy for amateur or novice coaches to instruct safer tackle practice in youth rugby playing populations.

A Novel Approach to Assessment of Perceptual-Motor Efficiency and Training-Induced Improvement in the Performance Capabilities of Elite Athletes

Standard clinical assessments of mild traumatic brain injury are inadequate to detect subtle abnormalities that can be revealed by sophisticated diagnostic technology. An association has been observed between sport-related concussion (SRC) and subsequent musculoskeletal injury, but the underlying neurophysiological mechanism is not currently understood. A cohort of 16 elite athletes (10 male, 6 female), which included nine individuals who reported a history of SRC (5 male, 4 female) that occurred between 4 months and 8 years earlier, volunteered to participate in a 12-session program for assessment and training of perceptual-motor efficiency. Performance metrics derived from single- and dual-task whole-body lateral and diagonal reactive movements to virtual reality targets in left and right directions were analyzed separately and combined in various ways to create composite representations of global function. Intra-individual variability across performance domains demonstrated very good SRC history classification accuracy for the earliest 3-session phase of the program (Reaction Time Dispersion AUC = 0.841; Deceleration Dispersion AUC = 0.810; Reaction Time Discrepancy AUC = 0.825, Deceleration Discrepancy AUC = 0.794). Good earliest phase discrimination was also found for Composite Asymmetry between left and right movement directions (AUC = 0.778) and Excursion Average distance beyond the minimal body displacement necessary for virtual target deactivation (AUC = 0.730). Sensitivity derived from Youden's Index for the 6 global factors ranged from 67 to 89% and an identical specificity value of 86% for all of them. Median values demonstrated substantial improvement from the first 3-session phase to the last 3-session phase for Composite Asymmetry and Excursion Average. The results suggest that a Composite Asymmetry value ≥ 0.15 and an Excursion Average value ≥ 7 m, provide reasonable qualitative approximations for clinical identification of suboptimal perceptual-motor performance. Despite acknowledged study limitations, the findings support a hypothesized relationship between whole-body reactive agility performance and functional connectivity among brain networks subserving sensory perception, cognitive decision-making, and motor execution. A complex systems approach appears to perform better than traditional data analysis methods for detection of subtle perceptual-motor impairment, which has the potential to advance both clinical management of SRC and training for performance enhancement.

Protective Football Headgear and Peripheral Visuomotor Ability in NCAA Football Athletes: The Role of Facemasks and Visors

The purpose of this investigation was to determine the effects of varying facemask reinforcement and visor tint on peripheral visuomotor abilities in collegiate football players. Division I NCAA football players (n = 14) completed two peripheral visuomotor experiments: (1) Varying facemask reinforcement, (2) Varying visor tinting. In experiment 1, participants were tested under the following conditions: baseline (no helmet; BL), helmet + light (HL), helmet + medium (HM), helmet + heavy (HH), and helmet + extra heavy (HXH) reinforced facemasks. In experiment 2, participants were tested under the following conditions: baseline (no helmet; BL), helmet only (HO), helmet + clear (HCV), helmet + smoke-tinted (HSV), and helmet + mirror-tinted (HMV) visors. For each condition, a 60 s peripheral visuomotor test was completed on a Dynavision D2 visuomotor board. For experiment 1, the BL peripheral reaction time (PRT) was faster than all facemask conditions (p < 0.05). Furthermore, PRT was impaired with the HXH compared to HL (p < 0.001), HM (p < 0.001), and HH (p = 0.001). Both HH and HXH resulted in the potentiation of PRT impairments in the outermost and inferior peripheral visual areas (p < 0.05). In experiment 2, BL PRT was faster than all helmeted conditions (p < 0.05). Additionally, PRT was slower in HSV (p = 0.013) and HMV (p < 0.001) conditions compared to HO. HMV resulted in slower PRT in all peripheral areas (p < 0.05) while PRT was impaired only in outer areas for HSV (p < 0.05). Wearing protective football headgear impairs peripheral visuomotor ability. Lighter reinforced facemasks and clear visors do not appear to exacerbate impairment. However, heavier reinforced facemasks and tinted visors further decrease visuomotor performance in outer and inferior visual areas, indicating a potential need for considerations of on-field player performance and safety.