Walking draws from a limited pool of attentional resources. Dual-task assessments, where individuals perform a cognitive task while walking, often reveal changes in gait and balance due to competing attentional demands. As cognitive task difficulty increases, the resources necessary to complete the task also increase, causing greater interference with gait and balance. However, these interactions are typically examined using contrived tasks, such as mental arithmetic, that do not often occur during walking. Therefore, it is unclear how the cognitive processes commonly engaged during walking interfere with gait and balance. In this study, we investigated whether increasing the attentional demand of spatial navigation, a cognitive process intrinsically linked to movement, interferes with gait and balance. Healthy adults completed an ambulatory virtual reality homing task in which they walked through a virtual environment and navigated to previously visited locations while wearing ankle and lumbar trackers. We increased the attentional demand of navigation by removing sensory cues during homing: full cues, body-based cues only, or visual cues only. Navigation performance declined as sensory cues were removed, but we observed no corresponding changes in spatiotemporal gait and balance metrics. These results show that, in healthy adults, increasing the attentional demand of spatial navigation did not interfere with gait and balance during real-world movement. These finding suggests that locomotor control may be robust to navigation-related cognitive demands. Further research is needed to determine why navigation did not interfere with mobility and to clarify the relationship between these processes.

Mild traumatic brain injury (mTBI) often presents with symptoms of dizziness, headache, and brain fog. Prior work has linked these symptoms to impaired autonomic nervous system function and associated changes in cerebral blood flow after mTBI. Arterial baroreflex function is central to the regulation of cerebral perfusion—modulating heart rate (HR) and blood pressure (BP) in response to postural changes and daily activity—and thus, of particular interest in understanding symptoms resulting from head trauma. This study sought to characterize sympathetic and parasympathetic baroreflex function in individuals with mTBI (≤14 days post injury) using standardized autonomic testing, and to assess the relationship between autonomic impairment and symptom severity. Seventy participants (35 mTBI, 35 age- and sex-matched controls) completed symptom questionnaires and a standardized autonomic battery that included heart rate variability during deep breathing, Valsalva maneuver, and 10-min head-up tilt (HUT) testing with beat-to-beat HR and BP monitoring. Outcome measures included HR/BP variability (SD), along with low frequency (LF) and high frequency power during supine and HUT phases. LF power during HUT was designated as the primary outcome of interest. Correlation and regression analyses assessed the relationship between autonomic outcome measures and postconcussion related symptom severity scores (Rivermead Post-Concussion Symptom Questionnaire-13), while controlling for potential confounders. Group-wise comparisons revealed significantly lower HR and BP variability, as well as reduced LF power of mean BP during HUT in the mTBI cohort compared to controls ( p = 0.002); LF power of HR was also significantly lower in mTBI compared to controls ( p = 0.011). Associations between autonomic metrics and symptom severity scores were weak. Individuals with mTBI (≤14 days since injury) exhibited blunted sympathetic baroreflex responses to orthostatic challenge as well as reduced HR/BP variability. These findings suggest physiological impairment in sympathetic activation post-mTBI, which may contribute to stressor-response based clinical symptomatology, but does not fully explain global symptom burden. Future studies should employ domain-specific symptom assessments (e.g., differentiating orthostatic from vertiginous or proprioceptive dizziness) and targeted physiological testing to further elucidate these relationships.

Background and Purpose: Reduction in ambulation levels has been described as a clinical “red flag” that represents the emergence of disability in individuals with Parkinson disease (PD). Multiday ambulatory activity measures may capture disability not detected by standard clinical assessments. However, the influence of disease severity and nonmotor symptoms on ambulatory activity remains unclear. This study aimed to examine the association between daily ambulatory activity and motor disease severity, assessed in both medication states, and to identify which non-motor symptoms were associated with daily step accumulation in individuals with mild to moderate PD. Methods: Mean daily steps were calculated over 7 days in 198 participants with PD. Motor and nonmotor symptoms were characterized using Movement Disorders Society—Unified Parkinson Disease Rating Scale (MDS-UPDRS) Part I, III, and IV. Descriptive statistics were calculated at baseline to characterize participant demographics and clinical characteristics. Linear regressions modeled the association between motor/nonmotor signs/symptoms and ambulatory activity, adjusting for age, race, and body mass index. Results: Median daily step count was 5180 (interquartile range: 3521-7199). Standardized off-medication MDS-UPDRS III scores were significantly associated with fewer mean daily steps, while on-medication scores were not, though the magnitude of this association was modest. Among nonmotor symptoms, a self-reported complaint of lightheadedness upon standing was associated with approximately 2000 fewer mean daily steps. Conclusion: A self-report of lightheadedness upon standing showed a clinically meaningful association with reduced ambulatory activity, while motor severity, even assessed in the standardized off-medication state, showed only a modest association. These findings highlight the value of nonmotor symptom assessment, particularly cardiovascular autonomic screening, in understanding real-world disability in PD.

INTRODUCTION:Ambulatory turning is a fundamental component of everyday mobility and military readiness, yet standard clinical assessments do not examine turns, an important component of mobility. The objective is to investigate which demographic and anthropometric factors, and military status impact peak turning velocities during complex and ecologically valid turning tasks and to report normative data. METHODS:Data from 94 healthy civilians and 40 service members, aged 18-50 years, were included. Participants performed a straight-path walk with 180° turns, the modified Illinois Agility Test (mIAT) with slalom, end, and middle turns, and a Complex Turning Course (CTC) with 45°, 90°, and 135° turns Peak turning velocities were measured using a wearable sensor placed around the waist. Multiple linear regression models were used to assess the influence of military status, sex, age, and body mass index (BMI) on turning velocities. RESULTS:Military status and sex were significant predictors of peak turning velocities. Specifically, service members turned significantly faster during slalom turns while running and during 45°, 90°, and 135° turns, and female participants exhibited faster turning during 180° turns and slalom turns. We also report the normative values of peak turning velocities for each turn type, stratified by military status and sex. CONCLUSION:Military status and sex were the primary demographic factors that affected turning performance. The normative values presented in this study provide a benchmark for clinicians to identify subtle turning deficits to monitor rehabilitation progress in neurological populations, and to make return-to-activity decisions for individuals with impaired mobility.

OBJECTIVE:To compare head motion capacity during a prescribed in-laboratory task with head motion performance in free-living daily life in individuals with mild traumatic brain injury (mTBI) and healthy controls. A secondary objective was to assess whether in-laboratory peak head motion metrics were associated with near maximal (95th percentile) free-living movements. SETTING:Research laboratory and participants' daily environments over 7 days of continuous monitoring. PARTICIPANTS:Twenty-three adults participated: 10 individuals with subacute, symptomatic mTBI (5F; age 30.3 (7.7) years; 35.2 (20.1) days postinjury) and 13 healthy controls (7F; age 31.9 (9.6) years). Participants were free of neurological, musculoskeletal, or balance-affecting conditions. DESIGN:Observational study combining a laboratory gait task with horizontal head turns and a 7-day free-living monitoring period using wearable inertial sensors on the head and lumbar spine. MAIN OUTCOME MEASURES:In-laboratory head turn amplitude and peak angular velocity (capacity); daily-life amplitude and angular velocity distributions (mean, median, 95th percentile), intra- and interday variability (performance); and associations with free-living measures. RESULTS:Individuals with mTBI demonstrated slower in-laboratory head turns than controls (223.53 (62.32) deg/s versus 302.01 (55.88) deg/s; P = 0.006), with no difference in amplitude. Daily-life amplitude and velocity did not differ between the groups. However, mTBI participants showed consistently smaller intra- and interday variability (P < 0.05), indicating more constrained daily movement patterns. Associations between in-laboratory peaks and free-living 95th percentile values were weak (r = -0.22 for amplitude; r = 0.10 for angular velocity). CONCLUSION:Although mTBI participants show reduced head motion capacity in laboratory tasks, their average daily-life kinematics are comparable to healthy adults. Reduced variability suggests constrained free-living movement strategies. These findings highlight the dissociation between capacity and performance and support integrating both laboratory assessments and continuous monitoring as complementary measures to fully characterize motor behavior following mTBI.

We examine the effects of concussion on visual, proprioceptive, and vestibular sensory integration using a virtual reality (VR)-adapted sensory organization test (SOT) and a VR navigational homing task. We conducted a descriptive analysis of performance measures and found that concussion participants integrate sensory cues differently than healthy controls across the SOT and the navigation task.

Falls are the primary cause of mild traumatic brain injury (mTBI) among older adults, yet limited research has examined patterns of clinical care, mobility, and subsequent fall risk in this population. The objective of this study was to evaluate outpatient physical or occupational therapy (PT/OT) referral patterns and assess physical function and fall risk status of older adults with mTBI. We analyzed acute care and 2-week post-mTBI assessment data from a prospective cohort study of adults aged 65 and older with mTBI treated at a level 1 trauma center and six affiliated hospitals 2023-2025 and meeting eligibility criteria. Of 625 that were confirmed eligible, 155 consented to participate in the study. Of these, five were missing the 2-week assessment and nine were missing PT/OT referral information, leaving 141 in the current study. The exposure of interest was referral to PT/OT at discharge, obtained from medical records. Two-week post-mTBI assessments included the Short Physical Performance Battery (SPPB) and the Four-Square Step Test (FSST). Statistical comparisons between exposure groups were made using Fisher's exact test, Student's t-test or the Wilcoxon rank-sum test. Participants (n = 141) were on average 76.1 (standard deviation 7.3) years old and 56.0% female. Falls were the primary cause of mTBI (89%). At the 2-week assessment, participants demonstrated poor physical performance: 53% had impaired SPPB (<10), 62% had impaired FSST (>15 sec), and 65% had slow gait speeds (<0.80 m/s), all indicative of elevated fall risk. Only 34 (24%) were referred to PT/OT at discharge. Those referred were more likely to have received an inpatient PT/OT consultation (97% vs. 22%, p < 0.001). Among participants not referred to PT/OT, 46% had impaired SPPB, 58% had impaired FSST, and 60% had slow gait speed, indicating high fall risk. Less than a quarter of older adults with primarily fall-related mTBI received any discharge PT/OT referral despite clear mobility and balance deficits. This critical gap in post-discharge rehabilitation underscores a disconnect between fall-prevention guidelines and clinical practice, leaving many older adults at high risk of recurrent falls and injuries.

Background Recurrent falls associated with Parkinson's disease (PD) contribute to diminished quality of life and treatment expense. Current fall prediction models do not adequately predict the transition from non-faller to recurrent faller in people with Parkinson's disease (PwPD). The aim of this project was to develop a machine learning model to identify fall risk to characterize the transition to a recurrent faller. Methods Baseline clinical motor, biomechanical, cognitive, and quality of life data from 246 PwPD in a clinical trial were combined with subsequent falls reported in diaries over 12 months. Fall-naïve participants (n = 174) were regressed on baseline data to develop a fall conversion prediction model using an XGBoost algorithm. Mean Area Under the Curve (AUC) under repeated cross-validation was the primary performance metric, with a feature importance analysis highlighting contributing variables. Results The derived model achieved an across-fold mean cross-validated AUC of 0.63, with mean sensitivity and specificity of 66% and 51%, respectively, and higher sensitivity of 77% for multiple falls, all at a threshold of 0.2. Features contributing to model performance included three biomechanical balance assessments, NeuroQoL lower extremity and MDS-UPDRS part II questionnaires, the Trails Making Test A and the Symbol Digit Matching Test. Conclusions The utilization of multifaceted data, biomechanical balance and self-report measures has utility in identifying PwPD at risk of experiencing a first fall and conversion to recurrent faller. Greater precision in identifying the first and subsequent falls has potential to guide interventions and behavior modification to mitigate transition to recurrent faller. Trial registry name Pragmatic Cyclical Lower Extremity Exercise Trial for Parkinson's Disease (CYCLE-II) Trial URL NCT04000360.

BACKGROUND:Mild traumatic brain injury (mTBI) can lead to persistent balance impairments, affecting daily functioning. While mTBI deficits in static and dynamic balance are well-documented, reactive balance-essential for recovering from perturbations-remains understudied, and the relationship with symptom severity and quality of life remains unclear. OBJECTIVE:Examine reactive balance across different stages of mTBI recovery and its association with self-reported symptoms and quality of life. METHODS:This cross-sectional study included 82 participants: 19 with acute (4-14 days post-injury), 11 with sub-acute (3-12 weeks post-injury), 11 with chronic (>12 weeks post-injury) mTBI, and 41 healthy controls. Reactive balance was assessed using the Instrumented-modified Push and Release under both single and cognitive dual-task conditions, measuring time to stability and step latency. RESULTS:Participants with acute mTBI had longer step latencies (P = .004 single-task; P = .016 dual-task) but no differences in time to stability compared to controls, while people with chronic mTBI exhibited longer time to stability (P = .004 single-task; P = .017 dual-task) but no difference in step latencies compared to controls. Dizziness and total symptom severity were moderately associated with single- and dual-task time to stability and dual-task step latency acutely, and with single-task time to stability and dual-task step latency in the sub-acute phase. CONCLUSIONS:Reactive balance deficits persist chronically after mTBI and differ between people with acute, sub-acute, and chronic symptoms. These differences suggest people with chronic symptoms may prioritize different aspects of balance control compared to the people in the acute stage of recovery related to functional adaptations to self-reported symptoms.

BACKGROUND AND PURPOSE:It has been proposed that a structured exercise program will increase overall physical activity in people with Parkinson's disease (PwPD). Initial studies present conflicting results. The aim of this project was to determine the impact of a home-based aerobic exercise (AE) program on overall physical activity over 12 months in PwPD. METHODS:This project was a secondary analysis of data gathered during a multisite randomized controlled clinical trial. Individuals with Parkinson's disease were randomized to a home-based AE or usual and customary care (UCC) group. The AE group exercised 3×/wk, progressing to 30-45 minutes, for 12 months on a commercially available stationary cycle. Physical activity for both groups was captured by a lower extremity activity monitor. The difference in overall physical activity between the UCC and AE groups was evaluated using a linear mixed model. RESULTS:A total of 118 and 119 people were included in the AE (mean [standard deviation] age 62.5 [8.1] years; 67.8% male) and UCC (mean [standard deviation] age 65.3 [8.2] years; 66.4% male) groups, respectively. Mean physical activity per day was 19% (~1000 steps) higher in the AE group compared with the UCC group. In the AE group, physical activity was 85% higher on exercise than nonexercise days. Both groups exhibited an overall negative trend in physical activity over 12 months. CONCLUSIONS:Physical activity gained from AE in a cohort of PwPD was additive to usual activity, as physical activity in the AE group remained considerably higher than the UCC group throughout the year. The increase did not arrest the gradual annual declines in physical activity among PwPD but may create a buffer to the decline. Physical therapists should prescribe structured AE programs to increase overall physical activity in PwPD.

Background Postural instability is a common observation after concussions, with balance assessments playing a crucial role in clinical evaluations. Widely used post-concussion balance tests focus primarily on static and dynamic balance, excluding the critical aspect of reactive balance. Objectives This study investigated the acute and longitudinal effects of concussion on reactive balance in collegiate athletes. Methods Concussed and healthy matched controls NCAA division I athletes were assessed at pre-season baseline and 4 post-concussion timepoints: acute, pre-return-to-play (RTP), post-RTP, and 6 months post-concussion. The instrumented-modified Push and Release test measured reactive balance during single- and dual-task conditions. Longitudinal effects of concussions on time to stability and step latency metrics were investigated applying Generalized Estimating Equations. Results Acutely after concussion, athletes demonstrated impaired reactive balance, indicated by longer times to stability, in dual-task conditions ( P = .004). These acute impairments were transient and recovered over time. Exploratory analyses revealed that athletes who sustained their first lifetime concussion exhibited both acute ( P = .037) and longitudinal ( P = .004 at post-RTP) impairments in single- and dual-task compared to controls with no lifetime concussion. Conclusions This comprehensive evaluation provides insights into the multifaceted nature of post-concussion impairments and emphasizes the importance of considering cognitive demand and history of concussions in assessing athletes’ balance.

This narrative review examines the utility of gait digital biomarkers in Parkinson’s disease (PD) research and clinical trials across four contexts: disease susceptibility/risk, disease progression, response to exercise, and fall prediction. The review of the literature to date suggests that upper body characteristics of gait (e.g., arm swing, trunk motion) may indicate susceptibility/risk of PD, while pace aspects (e.g., gait speed, stride length) are informative for tracking disease progression, exercise response, and fall likelihood. Dynamic stability aspects (e.g., trunk regularity, double-support time) worsen with disease progression but can improve with exercise. Gait variability emerges as a sensitive biomarker across all 4 contexts but with low specificity. The lack of standardized gait testing protocols and the lack of a minimum set of quantified digital gait biomarkers limit data harmonization across studies. Future studies, using a commonly agreed upon protocol, could be used to demonstrate the utility of specific gait biomarkers for clinical practice.

OBJECTIVE:To derive and evaluate an alternative equation to estimate maximal heart rate in persons with Parkinson disease (PD) in the absence of structured exercise testing using observed maximal heart rate data from a maximal cardiopulmonary exercise test (CPET) and basic demographic and clinical data. DESIGN:Baseline data from a randomized controlled trial. SETTING:Academic Medical Center. PARTICIPANTS:Eighty-two persons with mild-to-moderate PD who completed a CPET. INTERVENTIONS:Not applicable. MAIN OUTCOME MEASURES:A linear regression model was fit to maximal heart rate from CPET using the relaxed least absolute shrinkage and selection operator (lasso) and 7 readily clinically accessible candidate covariables. Model fit was assessed by leave-one-out cross-validation. Maximal heart rates from the CPET were compared with estimates from the regression model and from 2 traditional age-based maximal heart rate estimators: (220 - age) and [208 - (0.7 × age)]. RESULTS:The regression-based heart rate estimator was [166 - (1.15 × age) + (0.60 × resting heart rate)] and most closely fit the observed maximal heart rate from the CPET. The (220 - age) and [208 - (0.7 × age)] equations overestimated maximal heart rate for 88% and 94% of the participants, respectively. The mean square error of the regression-based estimator was 63% and 75% lower than those of the 2 traditional age-based estimators, respectively. CONCLUSIONS:Overestimating maximal heart rate generates prescribed target heart rate zones that are likely unachievable during aerobic exercise. The proposed regression-based maximal heart rate estimator most closely fit observed maximal heart rates from the CPET. Adoption of this estimator, based on both age and resting heart rate, may improve estimated maximal heart rate accuracy and thus provide more appropriate and achievable exercise heart rate zones for persons with PD in the absence of a CPET.

BACKGROUND:Approximately 25 % of pregnant people fall during the course of their pregnancy. While most falls during pregnancy occur during complex, dynamic movements, prior research on balance in pregnant people has largely focused on static posture. The present study aims to investigate dynamic balance and mobility throughout gestation by examining relatively more complex movements than traditional assessments of gait and balance in pregnant people. It is the first study to quantify two common clinical tests, the tandem gait test and the Timed Up and Go test, that assess mobility and fall risk via IMUs within pregnancy. METHODS:A total of 30 pregnant people (1st trimester: n = 10, 2nd trimester: n = 10, 3rd trimester: n = 10) and 10 healthy nonpregnant control females completed a tandem gait test and the Timed Up and Go test. Time to completion and measures of movement quality such as smoothness, peak turning speed, and mediolateral sway via the root mean square of center of mass acceleration, obtained through inertial measurement units (Opal v2, APDM Inc.), were compared between groups. FINDINGS:Overall, pregnant individuals completed both tests slower as gestational age increased. Pregnant people also demonstrated a similar movement quality, to healthy controls, rather than maintaining movement speed. INTERPRETATION:We speculate that reduced movement speed may be a compensatory strategy used during pregnancy to safely move despite increased mass and limited thoracopelvic rotations. Altogether, these findings contribute to a deeper understanding of the context-dependent effects of pregnancy on dynamic balance and mobility.

INTRODUCTION:The Vestibular/Ocular Motor Screening (VOMS) was created as a brief clinical screening tool for identifying vestibular and ocular motor symptoms and impairments post-concussion. It was found to have predictive validity in correctly identifying concussed athletes from healthy controls. In 2018, the Military Acute Concussion Evaluation 2 (MACE2) replaced the original Military Acute Concussion Evaluation (MACE); the most prominent change between the MACE and MACE2 was the addition of the VOMS. Despite its adoption into military medicine, it is not known if the addition of the VOMS to the MACE2 is acutely helpful, and if it provides additional information for diagnosis, prognosis, and/or management. The purposes of this systematic review were: (1) to determine the utility of the VOMS in correctly identifying concussed individuals, particularly as it pertains to military medicine; (2) to explore the extent to which the VOMS can inform concussion prognosis; and (3) to establish the value of the VOMS as a measure for monitoring the evolution of symptoms throughout a service member's course of care. MATERIALS AND METHODS:A comprehensive search of PubMed was performed from January 1, 2014 through August 16, 2023. Articles were included if they researched concussion or a related health condition or healthy controls and administered the VOMS. Articles were excluded if they discussed health conditions other than concussion; did not administer the VOMS; or were written in languages other than English. The tools used to assess methodological quality and risk of bias varied according to study design. Articles were classified into three primary domains: diagnosis, prognosis, and/or rehabilitation/recovery over time. RESULTS:A total of 231 articles were retrieved and 3 were duplicates, leaving 228 articles for review. Of the 228 articles screened, 100 relevant full-text articles were assessed for eligibility. Fifty-nine articles met our inclusion and exclusion criteria while the other 41 articles were rejected. Thirty-two articles helped to inform diagnosis, 15 prognosis, and 16 rehabilitation/recovery over time. CONCLUSIONS:The VOMS had excellent internal consistency and moderate to good test-retest reliability; however, a false-positive rate of 21.9% was found. Most studies indicated that a positive VOMS was associated with a delayed recovery. Several studies indicated that VOMS scores improved with targeted, active interventions and/or a symptom-guided progressive return to activity. The greatest limitation was the paucity of published evidence in the military population. More research is needed on the use of the VOMS in service members.

Wearable devices offer objective mobility metrics for continuous monitoring but often focus on traditional measures like step count or gait speed. Other quantitative metrics such as head kinematics may provide valuable insights into mobility, balance, and sensory integration, given the head's central role in coordinating vestibular, ocular, and postural control. Yet, basic knowledge about capturing daily living head turns, including participant compliance, algorithms, normative data, and reliability, is not yet established. This study aimed to resolve this knowledge gap by capturing head and trunk movement kinematics over a 7-day period and to establish normative data in healthy adults. Participants (n = 24) wore head-mounted sensors for an average of 16.38 hours per day (SD = 4.43), completing 5,163 (SD = 1,466) head turns daily, with 72% occurring independently of trunk motion. Head turn amplitude (M = 58.18°, SD = 4.26°) was comparable to lumbar turns, while peak velocity was higher for head turns (M = 104.49°/s, SD = 12.08°/s). By the second day, all head turn metrics achieved excellent reliability (ICC > 0.9), supporting the feasibility of multi-day monitoring. Additionally, we examined the relationship between head motion and other mobility metrics and established recommendations for implementing similar protocols for capturing future studies, including the minimum number of days required for reliable data collection. Findings from this study provide a foundation for future multi-day continuous monitoring of head kinematics in both healthy and clinical populations.

Balance and mobility problems are common consequences after mild traumatic brain injury (mTBI). However, turning and nonstraight gait, which are required for daily living, are rarely assessed in clinical tests of function after mTBI. Therefore, the primary goals of this study were to assess (1) the added value of clinic-based turning task variables, obtained using wearable sensors, over standard general assessments of mobility, and (2) assess the associations between general assessments of mobility, objective variables from clinic-based turning tasks, and ecologically relevant functional tasks. Fifty-three civilians with mTBI, 57 healthy civilian controls, and 36 healthy active-duty military controls participated across three sites. Participants were tested in a single session that encompassed self-reported questionnaires including demographic information and balance and mobility testing including the use of wearable sensors. Lasso regression models and the area under the receiver-operator characteristic curve (AUC) assessed diagnostic accuracy. Partial correlation coefficients assessed the relationship between each variable with ecologically relevant functional tasks. Multivariate models revealed high diagnostic accuracy, with an AUC of 0.92, using multiple variables from instrumented clinic-based turning tasks. The complex turning course (CTC) yielded the highest multivariate AUC (95% confidence interval [CI]) of 0.90 (0.84, 0.95) for a single task, and the average lap time from the CTC had the highest univariate AUC (95% CI) of 0.70 (0.58, 0.78). Turning variables provided added value, indicated by higher AUCs, over standard general assessments of mobility. Turning variables had strong associations with ecologically relevant functional tasks and outperformed general assessments of mobility, though there were slight differences in the relationship based on civilian versus military population. Clinic-based turning tasks, especially the CTC and modified Illinois Agility Test (mIAT), have high diagnostic accuracy, strong associations with ecologically relevant functional tasks, and require relatively short time(s) to complete. Compared to general assessments of mobility, clinic-based turning tasks may be more ecologically relevant to daily function. Future work should continue to examine the CTC and mIAT alongside other promising tools for return-to-activity assessments.

BACKGROUND:Gait impairments are common in individuals with mild traumatic brain injury (mTBI), presenting in the acute phase and often persisting in subtle ways over time. Despite the prominence of laboratory gait evaluations, a comprehensive understanding of gait deficits post-mTBI necessitates the examination of various gait domains in real-world environments. Assessing gait during a community ambulation task (CAT) may capture real-world challenges and influence focused interventions or rehabilitation in individuals with mTBI. RESEARCH QUESTION:The aim of the study was to compare gait performance across independent gait domains in individuals with and without mTBI using wearable sensors during both the CAT and laboratory tasks (i.e., 1-minute walk test). Additionally, associations between the CAT and single- and dual-task walking were investigated. METHODS:In this cross-sectional study, 107 participants, including individuals with mTBI (n = 52) and healthy controls (n = 55), underwent gait assessments during the CAT and 1-minute walk tests (single- and dual-task) using wearable sensors. Four independent gait domains (i.e., gait variability, pace, rhythm, and turning), consisting of thirteen gait variables, were analyzed. Statistical methods included t-tests and partial correlations, adjusted for covariates. RESULTS:Individuals with mTBI exhibited gait deficits across multiple gait domains. Specifically, increased gait variability, decreased gait pace and turns post mTBI were seen in the CAT and 1-minute walk tests. Notably, the CAT task exhibited greater gait differences in terms of gait variability and pace compared to the laboratory tasks. Across gait domains, the CAT revealed greater number of correlated measures with dual-task walking compared to single-task walking. SIGNIFICANCE:The community ambulation walking task showed more abnormalities across gait domains compared to laboratory walking tests, highlighting the potential importance of incorporating real-life, community ambulatory tasks into post-mTBI evaluation of mobility.

Background Accurate prediction of falls in patients with Parkinson's disease (PWP) is crucial for effective prevention efforts. Historically, fall risk models have heavily relied on motor features, overlooking the vital cognitive-motor interplay essential for locomotion. Methods Baseline assessments and year-long fall data from the CYClical Lower Extremity Exercise for Parkinson's disease II (CYCLE-II) trial's control group were utilized. A LASSO logistic regression model assessed thirty-seven demographic, motor, and cognitive variables to identify key fall predictors. To explore the practical implementation of predicting falls in a clinical setting, a second model was developed using a subset of nine candidate measures conducive for retrieval from electronic medical records. Models' accuracy was validated against Paul et al.'s 3-step fall prediction model. Results Analysis included 123 participants (mean age 65.3 ± 8.3 years, 66 % males, mean disease duration 4.9 ± 4.1 years). Seventy-two participants (58.5 %) fell at least once; with 33.1 % occurring during walking, 34.4 % resulting in injuries. The initial model identified 8 predictors with an AUC of 0.68. The second model, incorporating disease duration and cognitive tests, achieved an AUC of 0.67, comparable to Paul et al.'s validation (AUC 0.66). Participants with poorer information processing and spatial memory were more prone to falling over the 12-month period. Conclusions Impaired cognitive performance and longer disease duration were powerful predictors in identifying a future fall in PWP. The link between cognitive performance and potential for falling reinforces the strong interplay between gait and cognition.

OBJECTIVE:After mild traumatic brain injury (mTBI), autonomic nervous system dysfunction is thought to contribute to exercise intolerance and self-reported postconcussive symptoms (e.g. dizziness, lightheadedness, brain fog) but little has been done to establish this relationship in the literature. METHODS:Through recent literature review, it appears that few studies have assessed both autonomic function and exercise intolerance, and for those that have utilized varying methodologies making comparison across studies difficult. Some emerging research has identified potential impairment within the sympathetic nervous system after mTBI but no relationship between exercise tolerance testing and postconcussive symptoms has been established. CONCLUSION:For neuropsychologists, a physiologic understanding of the scope of autonomic dysfunction and appropriate assessment is vitally important, as autonomic nervous system impairment has the potential to impact sleep and mood, and subsequently cognitive function and mental health. When working in collaboration with other disciplines, referrals to exercise intolerance testing and laboratory based autonomic assessments may occur. However, given the lack of an established evidence, the use of exercise intolerance and/or related symptoms to clinically insinuate dysfunction of the autonomic nervous system function is likely premature, and a more thorough assessment of autonomic function via established batteries is more appropriate.