A scoping review on examination approaches for identifying tactile deficits at the upper extremity in individuals with stroke.

PURPOSE: Accurate perception of tactile stimuli is essential for performing and learning activities of daily living. Through this scoping review, we sought to summarize existing examination approaches for identifying tactile deficits at the upper extremity in individuals with stroke. The goal was to identify current limitations and future research needs for designing more comprehensive examination tools. METHODS: A scoping review was conducted in accordance with the Joanna Briggs Institute methodological framework and the PRISMA for Scoping Reviews (PRISMA-ScR) guidelines. A database search for tactile examination approaches at the upper extremity of individuals with stroke was conducted using Medline (Ovid), The Cochrane Library (Wiley), CINAHL Plus with Full Text (Ebsco), Scopus (Elsevier), PsycInfo (Ebsco), and Proquest Dissertations and Theses Global. Original research and review articles that involved adults (18 years or older) with stroke, and performed tactile examinations at the upper extremity were eligible for inclusion. Data items extracted from the selected articles included: if the examination was behavioral in nature and involved neuroimaging, the extent to which the arm participated during the examination, the number of possible outcomes of the examination, the type(s) of tactile stimulation equipment used, the location(s) along the arm examined, the peripheral nerves targeted for examination, and if any comparison was made with the non-paretic arm or with the arms of individuals who are neurotypical. RESULTS: Twenty-two articles met the inclusion criteria and were accepted in this review. Most examination approaches were behavioral in nature and involved self-reporting of whether a tactile stimulus was felt while the arm remained passive (i.e., no volitional muscle activity). Typically, the number of possible outcomes with these behavioral approaches were limited (2-3), whereas the neuroimaging approaches had many more possible outcomes ( > 15 ). Tactile examinations were conducted mostly at the distal locations along the arm (finger or hand) without targeting any specific peripheral nerve. Although a majority of articles compared paretic and non-paretic arms, most did not compare outcomes to a control group of individuals who are neurotypical. DISCUSSION: Our findings noted that most upper extremity tactile examinations are behavioral approaches, which are subjective in nature, lack adequate resolution, and are insufficient to identify the underlying neural mechanisms of tactile deficits. Also, most examinations are administered at distal locations of the upper extremity when the examinee's arm is relaxed (passive). Further research is needed to develop better tactile examination tools that combine behavioral responses and neurophysiological outcomes, and allow volitional tactile exploration. Approaches that include testing of multiple body locations/nerves along the upper extremity, provide higher resolution of outcomes, and consider normative comparisons with individuals who are neurotypical may provide a more comprehensive understanding of the tactile deficits occurring following a stroke.

Immediate Effects of High-Cadence Cycling on Core Outcomes in Individuals With Parkinson's Disease.

Despite a strong body of evidence supporting benefits of exercise to reduce severity of motor symptoms of Parkinson's Disease (PD) over time, research on the immediate impact of exercise as an adjunctive therapy for nonpharmacologic management of motor symptoms and mobility performance in people with PD is limited. The purpose of this study was to examine immediate effects of a single bout of high-cadence cycling on motor symptoms of PD and performance-based outcomes. Twenty individuals with idiopathic PD participated in a pretest/posttest study investigating immediate impacts of a single high-cadence cycling session on performance-based outcomes across multiple domains of motor function, mobility, and balance. Outcomes were analyzed based on time since last dose of levodopa/carbidopa medication. Immediate improvements were observed in motor symptoms of PD with significant improvements in performance across multiple balance systems, dynamic gait, and upper-extremity coordination following a cycling intervention.

Pragmatic approach to mobilizing individuals with critical illness due to COVID-19: clinical perspective.

PURPOSE: To provide pragmatic guidance for acute rehabilitation management and implementation of early mobility for individuals with critical illness due to COVID-19. METHODS: Clinical perspective developed through reflective clinical practice and narrative review of best available evidence. RESULTS: Current clinical practice guidelines do not provide guidance for implementation of early mobility interventions for individuals with critical illness due to COVID-19 who require enhanced ventilatory support or support of inhaled pulmonary artery vasodilators. Many individuals who may benefit from implementation of early mobility interventions are excluded by strict interpretation of current guidelines. CONCLUSIONS: Risk vs benefit of implementing early mobility interventions in individuals with critical illness due to COVID-19 can be mitigated through coordinated efforts of interdisciplinary teams to promote shared decision-making through therapeutic alliances with patients and their families. Clinicians must clearly define the goals of care, understand the limitations of monitoring equipment in the intensive care unit, prepare to titrate levels of oxygen based on an individual's physiologic response to mobility interventions, and help individuals maintain external goal-directed focus of attention to optimize outcomes of early mobility interventions.

Current clinical practice guidelines do not provide guidance for implementation of early mobility interventions for individuals with critical illness due to COVID-19 who require enhanced ventilatory support or support of inhaled pulmonary artery vasodilators.Risk vs benefit of implementing early mobility interventions in individuals with critical illness due to COVID-19 can be mitigated through coordinated efforts of interdisciplinary teams to promote shared decision-making through therapeutic alliances with patients and their families.Clinicians must clearly define the goals of care, understand the limitations of monitoring equipment in the intensive care unit, prepare to titrate levels of oxygen based on an individual's physiologic response to mobility interventions, and help individuals maintain external goal-directed focus of attention to optimize outcomes of early mobility interventions.

Combined Neurocognitive and Exercise Tolerance Testing Improves Objectivity of Buffalo Concussion Treadmill Test.

CONTEXT: The Buffalo Concussion Treadmill Test (BCTT) is a standard assessment of exercise tolerance utilized for exercise prescription following concussion and to inform decisions regarding return to play. One limitation of the BCTT is that interpretation of test results is dependent on individuals' self-report of symptom exacerbation with exertion. Symptoms following concussion are significantly underreported or unreported. Combining objective neurocognitive assessment with exercise tolerance testing may enable clinicians to objectively identify those requiring further assessment or rehabilitation before return to play. The purpose of this study was to investigate how performance on a neurocognitive assessment battery is affected by provocative exercise testing. DESIGN: Prospective cohort study, pretest/posttest. METHODS: A total of 30 participants included 13 women (43.3%), age 23.4 (1.93) years, height 173.56 (10) cm, weight 77.35 (16.3) kg, and 11 (36.7%) with history of concussion. All participants completed a neurocognitive assessment battery, including the Stroop Test and standardized assessments of working memory, attention, and information processing speed/accuracy in single-task (seated position) and dual-task conditions (walking on a treadmill at 2.0 miles per hour). The neurocognitive assessment battery was performed at baseline and after the standard BCTT test protocol. RESULTS: BCTT: Average percentage of heart rate maximum (%HRmax) = 93.97% (4.8%); average maximum rating of perceived exertion = 18.6 (1.5). Time-based performance in single-task and dual-task conditions significantly improved from baseline (P < .05) following maximal exercise testing on the BCTT for the following neurocognitive assessments: concentration-reverse digits, Stroop congruent, and Stroop incongruent. CONCLUSIONS: Healthy participants demonstrated improvements across multiple domains of neurocognitive performance following the exercise tolerance testing on the BCTT. Understanding normal responses in neurocognitive performance for healthy individuals following exercise tolerance testing may allow clinicians to more objectively monitor the trajectory of recovery following sports-related concussion.

Implementation of Early Rehabilitation in Severe COVID-19 Respiratory Failure: A Scoping Review.

The purpose of this scoping review is to describe current clinical practice guidelines (CPGs) for early rehabilitation for individuals hospitalized in an intensive care unit with COVID-19 and examine practice patterns for implementation of mobility-related interventions. Methods: PubMed, EMBASE, and CINAHL databases were searched from January 1, 2020, through April 1, 2022. Selected studies included individuals hospitalized with severe COVID-19 and provided objective criteria for clinical decision making for mobility interventions. A total of 1464 publications were assessed for eligibility and data extraction. The PRISMA-ScR Checklist and established guidelines for reporting for scoping reviews were followed. Results: Twelve articles met inclusion criteria: 5 CPGs and 7 implementation articles. Objective clinical criteria and guidelines for implementation of early rehabilitation demonstrated variable agreement across systems. No significant adverse events were reported. Conclusions: Sixty percent (3/5) of CPGs restrict mobility for individuals requiring ventilatory support of more than 60% Fio2 (fraction of inspired oxygen) and/or positive end-expiratory pressure (PEEP) greater than 10-cm H2O (positive end-expiratory pressure). Preliminary evidence from implementation studies may suggest that some individuals with COVID-19 requiring enhanced ventilatory support outside of established parameters may be able to safely participate in mobility-related interventions, though further research is needed to determine safety and feasibility to guide clinical decision making.

Heart Rate Variability as a Reliable Biomarker Following Concussion: A Critically Appraised Topic.

CLINICAL SCENARIO: Recent systematic reviews show conflicting information regarding the effect of concussion on cardiac autonomic function. Controlled aerobic exercise is the most popular intervention for those recovering from a concussion. There is a gap in the literature supporting the utility of objective metrics during exertional return to play protocols and rehabilitation. CLINICAL QUESTION: Can heart rate variability (HRV) during physical exertion be a reliable biomarker over time for those who suffered a sport-related concussion? SUMMARY OF KEY FINDINGS: A literature search produced 3 studies relevant to the clinical question. One, a prospective-matched control group cohort study, reported disturbances in HRV during physical exertion in those with a history of concussion, and identified persistent HRV dysfunction after resolution of subjective complaints, return to play, and with multiple concussive events. Second, a cross-sectional cohort study found an HRV difference in those with and without a history of concussion and in HRV related to age and sex. Finally, the prospective longitudinal case-control cohort study did not find sex or age differences in HRV and concluded that, although postconcussion HRV improved as time passed, resting HRV was not as clinically meaningful as HRV during exertional activities. CLINICAL BOTTOM LINE: There is emerging evidence to support the use of HRV as an observable biomarker, over time, of autonomic function during physical exertion following a sport-related concussion. However, the meaningfulness of HRV data is not fully understood and the utility seems individualized to the level of athlete, age, and sex and, therefore, cannot be generalizable. In order to be more clinically meaningful and to assist with current clinical decision making regarding RTP, a preinjury baseline assessment would be beneficial as an individualized reference for baseline comparison. STRENGTH OF RECOMMENDATION: Although HRV is not fully understood, currently, there is grade B evidence to support the use of individualized baseline exertional HRV data as comparative objective metric to assess the autonomic nervous system function, over time, following a concussive event.

Test-Retest Reliability of Postural Control Assessment on Biodex BioSway™.

Background: Recent protocols for posturographic assessment of postural control and balance have included head shake test conditions to challenge the vestibular contributions of postural control in an effort to increase the diagnostic accuracy of identifying individuals with impaired balance. However, evidence is limited regarding the test-retest reliability of such assessment protocols. Purpose: The purpose of this study was twofold: to determine the test-retest reliability of postural control assessment on the Biodex Biosway™, an accessible and field expedient tool for posturographic assessment, and to determine the test-retest reliability of the Head Shake Sensory Interaction and Balance Test (HS-SIB), an adaptation of the modified Clinical Test of Sensory Interaction and Balance (mCTSIB) which adds two head shake conditions to challenge the vestibular contributions to postural control. Study Design. This was a correlational time series cohort study completed in a biomechanics laboratory. Methods: The sample consisted of nineteen healthy adults (10 females, 9 males). Sway Index, Equilibrium Score, and the area of the ellipse enclosing 95% of the anterior-posterior (AP) and medial-lateral (ML) center of gravity (COG) displacement (AREA95) are the 3 summary variables. Standard Error of Measurement (SEM) and Minimum Detectable Change (MDC) are also reported. Results: Test-retest reliability was generally poor with limited exceptions. Moderate to good reliability was observed for the more challenging stance conditions (ICC range 0.58-0.81), including those with head shake. Conclusions: Field-expedient systems, such as the Biodex BioSway™, may offer reliable posturographic testing where gold-standard methods are not available. Clinicians should be aware that less demanding test conditions have limited reliability; however, test-retest reliability of this assessment tool is improved with more challenged stance conditions and the inclusion of a head shake task.

Influence of a clinical experiential activity on student confidence in conducting effective fall-risk assessment on older adults.

The ability to confidently perform fall-risk assessment on older adults is critical for Doctor of Physical Therapy (DPT) students prior to entering workforce. The complex nature of falls makes it challenging to teach it realistically in traditional classroom settings. This could lead to lack of confidence in performing effective assessments in real clinical situations. For this purpose, an evidence-based experiential fall-risk assessment activity was implemented in the curriculum. The purpose was to investigate if this activity improved students' confidence in performing fall-risk assessment. Twenty-eight students completed this activity on thirty-three older adults from a senior living community. A 13-item questionnaire was used to investigate confidence before and after the activity. Significant improvements in students' confidence were noted for administering client interview (p = .001, r = -0.43), 30-Second Chair Stand Test (p = .046, r = -0.34) and 10-Meter Walk Test (p = .011, r = -0.27). Additionally, students demonstrated excellent inter-rater reliability (ICC > 0.9) with the faculty experts for administering 5-Times Sit-to-Stand, 10-Meter Walk, Berg Balance Scale, 4-Stage Balance, Timed Up and Go and 30-Second Chair Stand tests, and good inter-rater reliability (ICC = 0.78) for Single-Limb Stance Time test. This activity had a positive impact on DPT students' confidence in conducting effective fall-risk assessment.

Utility of performance-based outcome measures (PBOMs) used in fall risk assessment tools for older adults.

This study investigated the diagnostic accuracy of different clusters of performance based outcome measures (PBOMs) recommended by two consensus-based guidelines: Stopping Elderly Accidents, Deaths, and Injuries (STEADI), and those recommended by a systematic review completed by the American Physical Therapy Association and Academy of Geriatric Physical Therapy (APTA-SR, APTA-SR3). 33 community-dwelling older adults (25 females, 8 males) aged mean 79.45 ±â€¯7.64 years participated in this study. Participants completed a fall history questionnaire and were evaluated via a battery of PBOMs for comparative analysis. The diagnostic accuracy of each PBOM cluster was analyzed retrospectively (previous 1 year fall history) and prospectively (6 month follow up). Retrospective analysis revealed the APTA-SR3 had the highest clinical utility and diagnostic accuracy: Sp 88.24% (63.56-98.54), Sn 62.5% (35.43-84.8), LR+ 2.35 (1.22-4.53), LR- 0.19 (0.05-0.73), accuracy 70.22% (51.83-84.81). Prospective analysis revealed the cluster of the APTA-SR and APTA-SR3 had identical diagnostic accuracy: Sn 100% (39.76-100), Sp 43.75% (19.75-70.12), LR+ 1.78 (1.15-2.74), LR- 0 (0), accuracy 60.62% (36.63-81.36). The APTA-SR 3 cluster demonstrated the highest diagnostic accuracy and in this study was the most effective and efficient group of PBOMs to identify fall risk in community dwelling older adults.

Self-Organized Structuring of Recurrent Neuronal Networks for Reliable Information Transmission.

Our brains process information using a layered hierarchical network architecture, with abundant connections within each layer and sparse long-range connections between layers. As these long-range connections are mostly unchanged after development, each layer has to locally self-organize in response to new inputs to enable information routing between the sparse in- and output connections. Here we demonstrate that this can be achieved by a well-established model of cortical self-organization based on a well-orchestrated interplay between several plasticity processes. After this self-organization, stimuli conveyed by sparse inputs can be rapidly read out from a layer using only very few long-range connections. To achieve this information routing, the neurons that are stimulated form feed-forward projections into the unstimulated parts of the same layer and get more neurons to represent the stimulus. Hereby, the plasticity processes ensure that each neuron only receives projections from and responds to only one stimulus such that the network is partitioned into parts with different preferred stimuli. Along this line, we show that the relation between the network activity and connectivity self-organizes into a biologically plausible regime. Finally, we argue how the emerging connectivity may minimize the metabolic cost for maintaining a network structure that rapidly transmits stimulus information despite sparse input and output connectivity.

Proposing a new algorithm for premanipulative testing in physical therapy practice.

In the field of physical therapy, there is debate as to the clinical utility of premanipulative vascular assessments. Cervical artery dysfunction (CAD) risk assessment involves a multi-system approach to differentiate between spontaneous versus mechanical events. The purposes of this inductive analysis of the literature are to discuss the link between cervical spine manipulation (CSM) and CAD, to examine the literature on premanipulative vascular tests, and to suggest an optimal sequence of premanipulative testing based on the differentiation of a spontaneous versus mechanical vascular event. Knowing what premanipulative vascular tests assess and the associated clinical application facilitates an evidence-informed decision for clinical application of vascular assessment before CSM.

Validity of Postural Sway Assessment on the Biodex BioSway™ Compared With the NeuroCom Smart Equitest.

CONTEXT: Current tools for sideline assessment of balance following a concussion may not be sufficiently sensitive to identify impairments, which may place athletes at risk for future injury. Quantitative field-expedient balance assessments are becoming increasingly accessible in sports medicine and may improve sensitivity to enable clinicians to more readily detect these subtle deficits. OBJECTIVE: To determine the validity of the postural sway assessment on the Biodex BioSway™ compared with the gold standard NeuroCom Smart Equitest System. DESIGN: Cross-sectional cohort study. SETTING: Clinical research laboratory. PARTICIPANTS: Forty-nine healthy adults (29 females: 24.34 [2.45] y, height 163.65 [7.57] cm, mass 63.64 [7.94] kg; 20 males: 26.00 [3.70] y, height 180.11 [7.16] cm, mass 82.97 [12.78] kg). INTERVENTION(S): The participants completed the modified clinical test of sensory interaction in balance on the Biodex BioSway™ with 2 additional conditions (head shake and firm surface; head shake and foam surface) and the Sensory Organization Test and Head Shake Sensory Organization Test on the NeuroCom Smart Equitest. MAIN OUTCOME MEASURES: Interclass correlation coefficient and Bland-Altman limits of agreement for Sway Index, equilibrium ratio, and area of 95% confidence ellipse. RESULTS: Fair-good reliability (interclass correlation coefficient = .48-.65) was demonstrated for the stance conditions with eyes open on a firm surface. The Head Shake Sensory Interaction and Balance Test condition on a firm surface resulted in fair reliability (interclass correlation coefficient = .50-.59). The authors observed large ranges for limits of agreement across outcome measures, indicating that the systems should not be used interchangeably. CONCLUSIONS: The authors observed fair reliability between BioSway™ and NeuroCom, with better agreement between systems with the assessment of postural sway on firm/static surfaces. However, the agreement of these systems may improve by incorporating methods that mitigate the floor effect in an athletic population (eg, including a head shake condition). BioSway™ may provide a surrogate field-expedient measurement tool.

Hey, look over there: Distraction effects on rapid sequence recall.

In the course of everyday life, the brain must store and recall a huge variety of representations of stimuli which are presented in an ordered or sequential way. The processes by which the ordering of these various things is stored and recalled are moderately well understood. We use here a computational model of a cortex-like recurrent neural network adapted by a multitude of plasticity mechanisms. We first demonstrate the learning of a sequence. Then, we examine the influence of different types of distractors on the network dynamics during the recall of the encoded ordered information being ordered in a sequence. We are able to broadly arrive at two distinct effect-categories for distractors, arrive at a basic understanding of why this is so, and predict what distractors will fall into each category.

Therapeutic effects of forced exercise cycling in individuals with Parkinson's disease.

Currently there is no cure for the progressive movement disorders associated with Parkinson's Disease (PD). Pharmacological management of movement disorders in PD are associated with significant negative side effects. Exercise improves the efficacy of anti-parkinsonian medication, but does not ameliorate the side effects. Consensus on the optimal mode of exercise training or dosing to improve motor function for individuals with PD is lacking. The new concept of forced exercise is gaining traction in the literature as a mode of exercise which has the potential to improve motor function in individuals with PD. The purpose of this article is to review the effects of forced exercise on specific components of motor function that would help guide clinical decision making and exercise prescription for the PD patient population. Collectively, the evidence provided in this review suggests that forced exercise may be safely added as an ancillary therapy to the medical management of PD.

Bridging structure and function: A model of sequence learning and prediction in primary visual cortex.

Recent experiments have demonstrated that visual cortex engages in spatio-temporal sequence learning and prediction. The cellular basis of this learning remains unclear, however. Here we present a spiking neural network model that explains a recent study on sequence learning in the primary visual cortex of rats. The model posits that the sequence learning and prediction abilities of cortical circuits result from the interaction of spike-timing dependent plasticity (STDP) and homeostatic plasticity mechanisms. It also reproduces changes in stimulus-evoked multi-unit activity during learning. Furthermore, it makes precise predictions regarding how training shapes network connectivity to establish its prediction ability. Finally, it predicts that the adapted connectivity gives rise to systematic changes in spontaneous network activity. Taken together, our model establishes a new conceptual bridge between the structure and function of cortical circuits in the context of sequence learning and prediction.

Plasticity-Driven Self-Organization under Topological Constraints Accounts for Non-random Features of Cortical Synaptic Wiring.

Understanding the structure and dynamics of cortical connectivity is vital to understanding cortical function. Experimental data strongly suggest that local recurrent connectivity in the cortex is significantly non-random, exhibiting, for example, above-chance bidirectionality and an overrepresentation of certain triangular motifs. Additional evidence suggests a significant distance dependency to connectivity over a local scale of a few hundred microns, and particular patterns of synaptic turnover dynamics, including a heavy-tailed distribution of synaptic efficacies, a power law distribution of synaptic lifetimes, and a tendency for stronger synapses to be more stable over time. Understanding how many of these non-random features simultaneously arise would provide valuable insights into the development and function of the cortex. While previous work has modeled some of the individual features of local cortical wiring, there is no model that begins to comprehensively account for all of them. We present a spiking network model of a rodent Layer 5 cortical slice which, via the interactions of a few simple biologically motivated intrinsic, synaptic, and structural plasticity mechanisms, qualitatively reproduces these non-random effects when combined with simple topological constraints. Our model suggests that mechanisms of self-organization arising from a small number of plasticity rules provide a parsimonious explanation for numerous experimentally observed non-random features of recurrent cortical wiring. Interestingly, similar mechanisms have been shown to endow recurrent networks with powerful learning abilities, suggesting that these mechanism are central to understanding both structure and function of cortical synaptic wiring.

Precise Synaptic Efficacy Alignment Suggests Potentiation Dominated Learning.

Recent evidence suggests that parallel synapses from the same axonal branch onto the same dendritic branch have almost identical strength. It has been proposed that this alignment is only possible through learning rules that integrate activity over long time spans. However, learning mechanisms such as spike-timing-dependent plasticity (STDP) are commonly assumed to be temporally local. Here, we propose that the combination of temporally local STDP and a multiplicative synaptic normalization mechanism is sufficient to explain the alignment of parallel synapses. To address this issue, we introduce three increasingly complex models: First, we model the idealized interaction of STDP and synaptic normalization in a single neuron as a simple stochastic process and derive analytically that the alignment effect can be described by a so-called Kesten process. From this we can derive that synaptic efficacy alignment requires potentiation-dominated learning regimes. We verify these conditions in a single-neuron model with independent spiking activities but more realistic synapses. As expected, we only observe synaptic efficacy alignment for long-term potentiation-biased STDP. Finally, we explore how well the findings transfer to recurrent neural networks where the learning mechanisms interact with the correlated activity of the network. We find that due to the self-reinforcing correlations in recurrent circuits under STDP, alignment occurs for both long-term potentiation- and depression-biased STDP, because the learning will be potentiation dominated in both cases due to the potentiating events induced by correlated activity. This is in line with recent results demonstrating a dominance of potentiation over depression during waking and normalization during sleep. This leads us to predict that individual spine pairs will be more similar after sleep compared to after sleep deprivation. In conclusion, we show that synaptic normalization in conjunction with coordinated potentiation--in this case, from STDP in the presence of correlated pre- and post-synaptic activity--naturally leads to an alignment of parallel synapses.

Slicing, sampling, and distance-dependent effects affect network measures in simulated cortical circuit structures.

The neuroanatomical connectivity of cortical circuits is believed to follow certain rules, the exact origins of which are still poorly understood. In particular, numerous nonrandom features, such as common neighbor clustering, overrepresentation of reciprocal connectivity, and overrepresentation of certain triadic graph motifs have been experimentally observed in cortical slice data. Some of these data, particularly regarding bidirectional connectivity are seemingly contradictory, and the reasons for this are unclear. Here we present a simple static geometric network model with distance-dependent connectivity on a realistic scale that naturally gives rise to certain elements of these observed behaviors, and may provide plausible explanations for some of the conflicting findings. Specifically, investigation of the model shows that experimentally measured nonrandom effects, especially bidirectional connectivity, may depend sensitively on experimental parameters such as slice thickness and sampling area, suggesting potential explanations for the seemingly conflicting experimental results.