Evaluating weaknesses of "perceptual-cognitive training" and "brain training" methods in sport: An ecological dynamics critique

The recent upsurge in "brain training and perceptual-cognitive training," proposing to improve isolated processes, such as brain function, visual perception, and decision-making, has created significant interest in elite sports practitioners, seeking to create an "edge" for athletes. The claims of these related "performance-enhancing industries" can be considered together as part of a process training approach proposing enhanced cognitive and perceptual skills and brain capacity to support performance in everyday life activities, including sport. For example, the "process training industry" promotes the idea that playing games not only makes you a better player but also makes you smarter, more alert, and a faster learner. In this position paper, we critically evaluate the effectiveness of both types of process training programmes in generalizing transfer to sport performance. These issues are addressed in three stages. First, we evaluate empirical evidence in support of perceptual-cognitive process training and its application to enhancing sport performance. Second, we critically review putative modularized mechanisms underpinning this kind of training, addressing limitations and subsequent problems. Specifically, we consider merits of this highly specific form of training, which focuses on training of isolated processes such as cognitive processes (attention, memory, thinking) and visual perception processes, separately from performance behaviors and actions. We conclude that these approaches may, at best, provide some "general transfer" of underlying processes to specific sport environments, but lack "specificity of transfer" to contextualize actual performance behaviors. A major weakness of process training methods is their focus on enhancing the performance in body "modules" (e.g., eye, brain, memory, anticipatory sub-systems). What is lacking is evidence on how these isolated components are modified and subsequently interact with other process "modules," which are considered to underlie sport performance. Finally, we propose how an ecological dynamics approach, aligned with an embodied framework of cognition undermines the rationale that modularized processes can enhance performance in competitive sport. An ecological dynamics perspective proposes that the body is a complex adaptive system, interacting with performance environments in a functionally integrated manner, emphasizing that the inter-relation between motor processes, cognitive and perceptual functions, and the constraints of a sport task is best understood at the performer-environment scale of analysis

The effectiveness of constraint-led training on skill development in interceptive sports: a systematic review (Clark, McEwan and Christie) – a commentary

Clark, McEwan and Christie's systematic review1 offers a timely examination of current literature assessing effects of a constraints-led approach (CLA) to training on ‘technical and cognitive skill in sport’, in comparison to traditional training methods. They concluded that, currently, there is strong evidence to advocate for the effects of training interventions that espouse benefits of constraints-led training on acquiring skill in interceptive actions. Clark, McEwan and Christie reported that 18 studies satisfied their proposed inclusion criteria and, of these studies, 77% provided evidence of the effectiveness of the CLA. Consequently, Clark, McEwan and Christie argued that a ‘the implementation of the constraints-led approach within interceptive sport can be advocated’ (p. 17). This is a revealing insight, which supports their claims that this finding ‘provides the opportunity for researchers to collect more compelling evidence to answer the question: “Does constraint-led training assist with the development of technical skills within interceptive sport?”’. While we endorse their call for more empirical evidence on the effectiveness of a CLA to practice and training design, we qualify it by highlighting some limitations of Clark, McEwan and Christie's systematic review

Application of a constraints-led approach to pedagogy in schools: embarking on a journey to nurture physical literacy in primary physical education

Background: Oversimplified, reductionist approaches to operationalising Physical Literacy (PL) have been a barrier to the development of a complex, dynamic and embodied understanding of the individual Physical Literacy journey. Further, there has been no appropriate approach that might allow practitioners to integrate Physical Literacy in Physical Education (PE). Whilst popular approaches, such as Teaching Games for Understanding (TGfU) and Game Sense (GS), for operationalising learner-centred and problem-based learning, have gained professional traction in the last three decades, the development of a comprehensive theoretical basis to underpin pedagogical principles has been neglected – particularly in Physical Education. Pedagogical approaches grounded in play have gained popularity as a vehicle for Physical Literacy development in Physical Education. Despite the prominence of a Constraint-Led Approach (CLA) in sport pedagogy to assist in developing ‘the intelligent, autonomous individual’ in sport, application to Physical Education is limited. Purpose: In this article, we propose key pedagogical principles of a Constraints-Led Approach (CLA) in primary physical education, underpinned by the theoretical framework of Ecological Dynamics (ED). Driven by the challenge of designing affordance landscapes for learning, we present our reflections on a recently designed PE curriculum for primary schools, Boing, which could facilitate the development of movement capacities in play-based curricula designed to nurture the Physical Literacy journey for individuals. An articulation of support for the key theoretical ideas is provided in this paper. Design: This is achieved through reflections on the play-based curriculum (BOING) founded on the principles of Ecological Dynamics (ED) underpinning a Constraints-Led approach (CLA) to better serve the implementation of a Physical Literacy focussed Physical Education in a Primary school setting based on key principles for delivery. Findings: Summarising the findings, the we were able to highlight the importance of developing key principles for delivering a theoretically informed curriculum that elicits key principles of Physical Literacy. Whilst movement skills are key, these approaches are able to elicit the intended outcomes in learners of confidence, motivation and competence (Whitehead 2010, 2016). Conclusions: A CLA affords the theoretical design of play-based curricula beyond just play or sport towards purposeful, inclusive learning environments. Practitioners should look to underpin their practice with key theoretical ideas. This paper is of particular interest to those coaches and teachers tasked with designing practical environments for learning beyond the rhetoric of skill development in sport

Should patients with abnormal liver function tests in primary care be tested for chronic viral hepatitis: cost minimisation analysis based on a comprehensively tested cohort

Background Liver function tests (LFTs) are ordered in large numbers in primary care, and the Birmingham and Lambeth Liver Evaluation Testing Strategies (BALLETS) study was set up to assess their usefulness in patients with no pre-existing or self-evident liver disease. All patients were tested for chronic viral hepatitis thereby providing an opportunity to compare various strategies for detection of this serious treatable disease. Methods This study uses data from the BALLETS cohort to compare various testing strategies for viral hepatitis in patients who had received an abnormal LFT result. The aim was to inform a strategy for identification of patients with chronic viral hepatitis. We used a cost-minimisation analysis to define a base case and then calculated the incremental cost per case detected to inform a strategy that could guide testing for chronic viral hepatitis. Results Of the 1,236 study patients with an abnormal LFT, 13 had chronic viral hepatitis (nine hepatitis B and four hepatitis C). The strategy advocated by the current guidelines (repeating the LFT with a view to testing for specific disease if it remained abnormal) was less efficient (more expensive per case detected) than a simple policy of testing all patients for viral hepatitis without repeating LFTs. A more selective strategy of viral testing all patients for viral hepatitis if they were born in countries where viral hepatitis was prevalent provided high efficiency with little loss of sensitivity. A notably high alanine aminotransferase (ALT) level (greater than twice the upper limit of normal) on the initial ALT test had high predictive value, but was insensitive, missing half the cases of viral infection. Conclusions Based on this analysis and on widely accepted clinical principles, a "fast and frugal" heuristic was produced to guide general practitioners with respect to diagnosing cases of viral hepatitis in asymptomatic patients with abnormal LFTs. It recommends testing all patients where a clear clinical indication of infection is present (e.g. evidence of intravenous drug use), followed by testing all patients who originated from countries where viral hepatitis is prevalent, and finally testing those who have a notably raised ALT level (more than twice the upper limit of normal). Patients not picked up by this efficient algorithm had a risk of chronic viral hepatitis that is lower than the general population

A Technical Assessment of a Commercial GFAP Lateral Flow Assay to Establish Proof-of-Concept for Use in Traumatic Brain Injury

Glial fibrillary acidic protein (GFAP) is an emerging biomarker for the detection of acute intracranial pathology following acute brain injuries such as traumatic brain injury (TBI), stroke, and hypoxic-ischaemic encephalopathy. We undertake a proof-of-concept technical assessment of a commercial lateral flow test (LFT) for the detection of GFAP [the Upfront DX LVOne GFAP lateral flow assay (LFA)], against GFAP concentrations measured using a gold-standard assay [Single Molecule Arrays (Simoa®)-based Human Neurology 4-Plex B assay] in a TBI population. The ability of the LVOne GFAP LFA for identification of samples with GFAP concentrations above the manufacturer’s reported lower limit of detection (≥ 0.2 ng/ml) was assessed, with further assessment of the association between the LVOne and a gold-standard assay made using Spearman’s rank correlation coefficient and linear-mixed-effects modelling. Of the 50 samples, 39 had serum GFAP concentrations exceeding the reported lower limit of detection, with the LVOne GFAP LFA having a 95% (95% CI: 83%, 99%) sensitivity and a 64% (95% CI: 31%, 89%) specificity for detecting a serum GFAP concentrations over this lower limit. There was a significant positive correlation (Rho = 0.94, p < 0.001) between the Quanterix Simoa® GFAP level and the LVOne semiquantitative score, with a significant positive association seen using a linear-mixed-effects model (p < 0.001). In conclusion, the Upfront DX LVOne GFAP LFA is sensitive for the detection of elevated serum GFAP levels, and as such, may be a useful adjunct to the care of patients with acute brain injuries in the pre-hospital setting

The neurological sequelae of pandemics and epidemics

Funder: NIHR Cambridge Biomedical Research Centre (GB)Funder: University of CambridgeAbstract: Neurological manifestations in pandemics frequently cause short and long-term consequences which are frequently overlooked. Despite advances in the treatment of infectious diseases, nervous system involvement remains a challenge, with limited treatments often available. The under-recognition of neurological manifestations may lead to an increase in the burden of acute disease as well as secondary complications with long-term consequences. Nervous system infection or dysfunction during pandemics is common and its enduring consequences, especially among vulnerable populations, are frequently forgotten. An improved understanding the possible mechanisms of neurological damage during epidemics, and increased recognition of the possible manifestations is fundamental to bring insights when dealing with future outbreaks. To reverse this gap in knowledge, we reviewed all the pandemics, large and important epidemics of human history in which neurological manifestations are evident, and described the possible physiological processes that leads to the adverse sequelae caused or triggered by those pathogens

Dynamic Changes in White Matter Abnormalities Correlate With Late Improvement and Deterioration Following TBI: A Diffusion Tensor Imaging Study.

OBJECTIVE: Traumatic brain injury (TBI) is not a single insult with monophasic resolution, but a chronic disease, with dynamic processes that remain active for years. We aimed to assess patient trajectories over the entire disease narrative, from ictus to late outcome. METHODS: Twelve patients with moderate-to-severe TBI underwent magnetic resonance imaging in the acute phase (within 1 week of injury) and twice in the chronic phase of injury (median 7 and 21 months), with some undergoing imaging at up to 2 additional time points. Longitudinal imaging changes were assessed using structural volumetry, deterministic tractography, voxel-based diffusion tensor analysis, and region of interest analyses (including corpus callosum, parasagittal white matter, and thalamus). Imaging changes were related to behavior. RESULTS: Changes in structural volumes, fractional anisotropy, and mean diffusivity continued for months to years postictus. Changes in diffusion tensor imaging were driven by increases in both axial and radial diffusivity except for the earliest time point, and were associated with changes in reaction time and performance in a visual memory and learning task (paired associates learning). Dynamic structural changes after TBI can be detected using diffusion tensor imaging and could explain changes in behavior. CONCLUSIONS: These data can provide further insight into early and late pathophysiology, and begin to provide a framework that allows magnetic resonance imaging to be used as an imaging biomarker of therapy response. Knowledge of the temporal pattern of changes in TBI patient populations also provides a contextual framework for assessing imaging changes in individuals at any given time point

Relationship Between Measures of Cerebrovascular Reactivity and Intracranial Lesion Progression in Acute TBI Patients: an Exploratory Analysis

Abstract: Background: Failure of cerebral autoregulation and progression of intracranial lesion have both been shown to contribute to poor outcome in patients with acute traumatic brain injury (TBI), but the interplay between the two phenomena has not been investigated. Preliminary evidence leads us to hypothesize that brain tissue adjacent to primary injury foci may be more vulnerable to large fluctuations in blood flow in the absence of intact autoregulatory mechanisms. The goal of this study was therefore to assess the influence of cerebrovascular reactivity measures on radiological lesion expansion in a cohort of patients with acute TBI. Methods: We conducted a retrospective cohort analysis on 50 TBI patients who had undergone high-frequency multimodal intracranial monitoring and for which at least two brain computed tomography (CT) scans had been performed in the acute phase of injury. We first performed univariate analyses on the full cohort to identify non-neurophysiological factors (i.e., initial lesion volume, timing of scan, coagulopathy) associated with traumatic lesion growth in this population. In a subset analysis of 23 patients who had intracranial recording data covering the period between the initial and repeat CT scan, we then correlated changes in serial volumetric lesion measurements with cerebrovascular reactivity metrics derived from the pressure reactivity index (PRx), pulse amplitude index (PAx), and RAC (correlation coefficient between the pulse amplitude of intracranial pressure and cerebral perfusion pressure). Using multivariate methods, these results were subsequently adjusted for the non-neurophysiological confounders identified in the univariate analyses. Results: We observed significant positive linear associations between the degree of cerebrovascular reactivity impairment and progression of pericontusional edema. The strongest correlations were observed between edema progression and the following indices of cerebrovascular reactivity between sequential scans: % time PRx > 0.25 (r = 0.69, p = 0.002) and % time PAx > 0.25 (r = 0.64, p = 0.006). These associations remained significant after adjusting for initial lesion volume and mean cerebral perfusion pressure. In contrast, progression of the hemorrhagic core and extra-axial hemorrhage volume did not appear to be strongly influenced by autoregulatory status. Conclusions: Our preliminary findings suggest a possible link between autoregulatory failure and traumatic edema progression, which warrants re-evaluation in larger-scale prospective studies

Association of early blood-based biomarkers and six-month functional outcomes in conventional severity categories of traumatic brain injury: capturing the continuous spectrum of injury

BACKGROUND: Traumatic brain injury is conventionally categorised as mild, moderate, or severe on the Glasgow Coma Scale (GCS). Recently developed biomarkers can provide more objective and nuanced measures of the extent of brain injury. METHODS: Exposure-response relationships were investigated in 2479 patients aged ≥16 enrolled in the Collaborative European NeuroTrauma Effectiveness Research in Traumatic Brain Injury (CENTER-TBI) prospective observational cohort study. Neurofilament protein-light (NFL), ubiquitin carboxy-terminal hydrolase L1 (UCH-L1), and glial fibrillary acidic protein (GFAP) were assayed from serum sampled in the first 24 h; concentrations were divided into quintiles within GCS severity groups. Relationships with the Glasgow Outcome Scale-Extended were examined using modified Poisson regression including age, sex, major extracranial injury, time to sample, and log biomarker concentration as covariates. FINDINGS: Within severity groups there were associations between biomarkers and outcomes after adjustment for covariates: GCS 13-15 and negative CT imaging (relative risks [RRs] from 1.28 to 3.72), GCS 13-15 and positive CT (1.21-2.81), GCS 9-12 (1.16-2.02), GCS 3-8 (1.09-1.94). RRs were associated with clinically important differences in expectations of prognosis. In patients with GCS 3 (RRs 1.51-1.80) percentages of unfavourable outcome were 37-51% in the lowest quintiles of biomarker levels and reached 90-94% in the highest quintiles. Similarly, for GCS 15 (RRs 1.83-3.79), the percentages were 2-4% and 19-28% in the lowest and highest biomarker quintiles, respectively. INTERPRETATION: Conventional TBI severity classification is inadequate and underestimates heterogeneity of brain injury and associated outcomes. The adoption of circulating biomarkers can add to clinical assessment of injury severity. FUNDING: European Union 7th Framework program (EC grant 602150), Hannelore Kohl Stiftung, One Mind, Integra LifeSciences, Neuro-Trauma Sciences, NIHR Rosetrees Trust

Association of Blood-Based Biomarkers and 6-Month Patient-Reported Outcomes in Patients With Mild TBI: A CENTER-TBI Analysis

BACKGROUND AND OBJECTIVES: There is seemingly contradictory evidence concerning relationships between day-of-injury biomarkers and outcomes after mild traumatic brain injury (mTBI). To address this issue, we examined the association between a panel of biomarkers and multidimensional TBI outcomes. METHODS: Participants with mTBI (Glasgow coma scores [GCSs] 13-15) were selected from Collaborative European NeuroTrauma Effectiveness Research in Traumatic Brain Injury, a European observational study recruiting patients with TBI with indication for brain CT and presentation within 24 hours. Exclusion criteria for this secondary analysis were age younger than 16 years, incomplete biomarker panel, death, or no recorded outcomes. Participants were separated into 2 groups, CT-negative and CT-positive. Multivariable binary logistic regression was used to assess the relation between the log biomarker level (glial fibrillary acidic protein [GFAP], neurofilament light [NfL], neuron-specific enolase [NSE], S100 calcium-binding protein B [S100B], tau, ubiquitin C-terminal hydrolase L1 [UCH-L1]) and dichotomized 6-month outcomes (functional outcomes [GOSE score <8], health-related quality of life [HRQoL; Quality of Life after Brain Injury-Overall Scale (QOLIBRI-OS) score <52, Short-Form 12-Item Survey version 2 Mental Component Summary (SF12v2 MCS) score <40, Short-Form 12-Item Survey version 2 Physical Component Summary (SF12v2 PCS) score <40], persistent postconcussion symptoms [Rivermead Post-Concussion Symptoms Questionnaire score ≥16], anxiety disorder [Generalized Anxiety Disorder-7 (GAD-7) score ≥8], depression [Patient Health Questionnaire-9 (PHQ-9) score ≥10], and post-traumatic stress disorder [PTSD Checklist for DSM-5 (PCL-5) score ≥33]). RESULTS: A total of 1,589 participants (865 CT-negative, 724 CT-positive) were included (77% GCS 15, median age 52 years, 66% male). Higher biomarker levels were associated with a GOSE score <8: CT-negative: S100B (odds ratio [OR] 1.78, 95% CI 1.43-2.23) and UCH-L1 (OR 1.16, 95% CI 1.01-1.33); CT-positive: GFAP (OR 1.22, 95% CI 1.11-1.36), NfL (OR 1.30, 95% CI 1.11-1.52), S100B (OR 1.51, 95% CI 1.23-1.86), tau (OR 1.36, 95% CI 1.17-1.59), and UCH-L1 (OR 1.34, 95% CI 1.17-1.53). In CT-positive participants, positive association was seen between NfL (OR 1.3, 95% CI 1.06-1.60) and UCH-L1 (OR 1.28, 95% CI 1.07-1.54) with QOLIBRI-OS; S100B (OR 1.32, 95% CI 1.02-1.70) with SF12v2 PCS; and NSE (OR 1.52, 95% CI 1.06-2.18) and UCH-L1 (OR 1.21, 95% CI 1.01-1.46) with the GAD-7. However, in CT-negative participants only, negative associations were seen between GFAP and impairment on the QOLIBRI-OS (OR 0.76, 95% CI 0.66-0.88), SF12v2 MCS (OR 0.71, 95% CI 0.61-0.82), SF12v2 PCS (OR 0.79, 95% CI 0.68-0.91), GAD-7 (OR 0.80, 0.68-0.95), PHQ-9 (OR 0.80, 95% CI 0.68-0.93), and PCL-5 (OR 0.80, 95% CI 0.66-0.97). DISCUSSION: Participants with higher biomarker levels had greater odds of impaired functional recovery. However, in CT-negative participants, higher GFAP concentrations were associated with better HRQoL and less impaired mental health. Further exploration is required of the patient phenotypes that may explain the relationships observed in this analysis