Sensory Organization Test Conditions Research Articles

Sensory reweighting of postural control requires distinct rambling and trembling sway adaptations

BackgroundImplementation of the Sensory Organization Test (SOT) under the rambling-trembling (RM-TR) framework allows for an examination of both individual sensory contributions and compensatory mechanisms, a valuable insight in research and clinical settings. Such investigation could substantially improve our ability to assess and treat fall risk in older adults and people living with neurological disorders. Research questionHow are RM and TR components of sway influenced by SOT-induced challenges in healthy adults? MethodsTwenty-three healthy adults (27.4±8 years; 10 male) volunteered to participate in this cross-sectional study. Each participant completed a VR-based SOT program, which included six conditions with varied visual environments (normal, blacked-out, conflict) and support surfaces (stable, unstable foam), while a force plate captured forces at the plantar surface. Center of pressure (COP) was calculated and decomposed into RM-TR components. For each time series, range, root-mean-square (RMS) and sample entropy (SampEn) were extracted. Individual contributions of somatosensation, vision, and vestibular sense, as well as the preference ratio, were calculated. Repeated measures ANOVA were used to compare the effects of time series type (COP, RM, TR) and SOT condition. Paired t-tests were used to assess the difference in preference ratio between RM and TR components. Results and significanceTR sway behavior was impacted significantly by the sensory challenges induced by the SOT procedure, while RM was largely unaffected. Such findings are characteristic of healthy individuals, capable of competently re-weighting sensory input, but still facing challenge-based adaptations. Additionally, the mediolateral SampEn preference ratio was higher in TR compared to RM, indicating potential differences in compensation strategies between supraspinal and spinal/peripheral control mechanisms. These findings serve as a foundation for future RM-TR analyses using SOT procedures, aiding in our ability to implement targeted diagnostic and treatment methods, ultimately reducing the incidence of falls in aging and individuals with neurological conditions.

Evaluation of Forward Head Posture, Balance, and Risk for Falls in Community-Dwelling Older Adults

Objective: This study investigated the influence of fear of falling, forward head posture (FHP), cervical proprioception, dynamic balance, and sensory integration on fall risk in older adults. Methods: Thirty-one participants were evaluated using tests designed to detect fall risk. FHP was assessed using a cervical range of motion device and craniovertebral angle (CVA) measurement. Results: Independent t tests were significant for Sensory Organization Test conditions 2 (P = .031) and 5 (P = .043) for FHP versus non-FHP groups. Regression analysis revealed that CVA could predict 16.7% variance in fall risk. Conclusion: CVA is a practical measure for measuring FHP and identifying fall risk in older adults.

The effect of brace use on balance in individuals with adolescent idiopathic scoliosis.

Patients with adolescent idiopathic scoliosis (AIS) have poorer standing balance compared with their healthy peers. However, the immediate effects of the braces used in the treatment on balance remain uncertain. To investigate the effect of brace use on balance and weight-bearing symmetry in patients with AIS and to compare the results of different brace designs. Observational. A total of 21 patients with AIS aged 10-17 years using 10 Boston and 11 Cheneau braces participated. Immediate balance and weight-bearing symmetries of patients with and without their own braces were evaluated. Balance assessment was performed using the Sensory Organization Test (SOT) on a computerized dynamic posturography device. Weight-bearing symmetry was evaluated on the computerized dynamic posturography device with the knees in full extension, with the knees flexed at 30°, 60°, and 90°. Regardless of its design, it was found that brace use had no effect on immediate balance and weight-bearing symmetry (p > 0.05). Of the patients using a Boston brace, unbraced SOT condition 2, 3, and 5 and composite scores were found to be higher than their braced scores (p < 0.05). Braced SOT condition 3 scores of the patients using a Cheneau brace were higher than those using a Boston brace (p = 0.037). Brace use and brace types have no statistical effect on weight-bearing symmetry. It was observed that brace use in patients with AIS has no positive effect on immediate balance and weight-bearing symmetry, and the use of Boston brace negatively affects immediate balance scores and increases visual dependence.

Recurrence Quantification Analysis as a Form of Postural Control Assessment: A Systematic Review

Human postural control is commonly assessed by center of pressure (CoP) displacement analysis. However, traditional linear parameters do not provide a complete picture of postural control, so a number of nonlinear analyses have been introduced. One of these is recurrence quantification analysis (RQA), which is used to determine the number and duration of repeated states in a dynamic system. This review aimed to show how the RQA measures look in different groups of subjects when assessing postural stability during quiet standing and how the authors interpret them. Therefore, a systematic review was conducted of papers published from 2000 to February 2023. Searched databases were PubMed, ScienceDirect, and EBSCO. Twenty-eight publications were included in this review. The RQA parameters most commonly found in papers are %DET (determinism), ENT (Shannon entropy), %REC (recurrence), and %LAM (laminarity). %LAM is the most sensitive factor in determining differences in CoP position between different age groups, as it describes motion fluidity. The vision affects the deterministic structure of CoP motions. When the sensory organization test conditions became difficult, CoP variability increased, while the %DET decreased. It was concluded that traditional and nonlinear methods provide complementary and not redundant information for assessing age- and health-related changes in standing balance.

Balance and Cognition in Male Collegiate Lacrosse Players.

Concussion screening among collegiate lacrosse athletes is a major safety priority. Although attention has been directed at concussion management following injury, less is known about the association between cognition and balance during preseason screening. The purpose of the study was to assess the relationship between balance and neurocognition among collegiate male lacrosse players and to examine predictive determinants of postural stability. Participants included a convenience sample of 49 male collegiate Division 3 lacrosse players who completed a demographic survey and performed the immediate postconcussion test (ImPACT) and instrumented Sensory Organization Test (SOT). There was a significant association between balance SOT performance and both verbal memory (r = .59, p < .01) and visual motor speed scores (r = .43, p < .05). Significant correlations between verbal memory and SOT Conditions 2, 5, and 6 were also noted (all p < .05). Verbal memory predicted 33% of the variance in the SOT composite balance score (p < .001). Our results indicate a significant relationship exists between postural stability and both verbal memory and visual processing speed among collegiate male lacrosse players and supports vestibulocortical associations. Findings warrant ongoing performance and executive function tracking and can serve as a conduit for integrated sensorimotor and dual-task training.

An Absence of Persistent Postural Stability Deficits Following a Sport Concussion in Collegiate Athletes.

The purpose of our study was to determine whether persistent postural stability deficits exist in athletes following sport concussion (SC) in comparison with preinjury (baseline) values using Sample Entropy (SampEn). Sports medicine clinic. Participants consisted of 71 collegiate athletes (44 male, 27 female) with an average age of 19.9 ± 0.96 years who had a history of 1 concussion that occurred during their time as a collegiate athlete. In our prospective, cohort design participants completed the Sensory Organization Test (SOT) at baseline, upon reporting symptom-free following a diagnosed SC, and upon establishing a new baseline prior to the start of the subsequent sport season. The SOT's condition scores were calculated and analyzed in alignment with the manufacturer's instructions. SampEn was calculated in the anterior-posterior (AP) and medial-lateral (ML) directions from the center-of-pressure oscillations over the 20-second time series for each SOT condition. The SOT and SampEn outcome scores for each condition were analyzed with repeated-measures analyses of variance. Significant main effects were observed for the SOT's conditions 3 ( F1.6, 114.8 = 7.83, P = .001, η2 = 0.10 [0.02-0.20]), 5 ( F1.8, 126.8 = 11.53, P < .001, η2 = 0.14 [0.04-0.25]), and 6 ( F1.9, 134.5 = 25.11, P < .001, η2 = 0.26 [0.14-0.37]), with significant improvements across time. Significant main effects were also observed for SampEn in the AP direction for conditions 3 ( F2, 140 = 7.59, P = .001, η2 = 0.10 [0.02-0.19]) and 6 ( F2, 140 = 6.22, P = .003, η2 = 0.08 [0.011-0.170]), with significant improvements across time. Following a diagnosed SC, our results suggest that collegiate athletes returned if not exceeded baseline values at the symptom-free and new baseline assessments. The application of linear and nonlinear measures of postural stability following a SC yielded similar outcomes in conjunction with a baseline assessment. Our findings support the clinical utility of the baseline SC assessment when evaluating persisting balance deficits when using linear or nonlinear measures.

Sensory Integration for Postural Control in Rheumatoid Arthritis Revealed by Computerized Dynamic Posturography

Rheumatoid arthritis (RA) is a systemic autoimmune disease that impairs mobility. How does sensory information influence postural responses in people with RA? The aim of this study was to evaluate the postural control of people with RA during a sensory organization test, comparing how sensory information influences postural responses in people with rheumatoid arthritis compared with healthy people. Participants were 28 women with rheumatoid arthritis (RA group) and 16 women without any rheumatoid disease (Control group CG). The Sensory Organization Test (SOT) was performed on a Smart Balance Master® (NeuroCom International, Inc., Clackamas, OR, USA) and center of pressure (COP) was measured. SOT conditions: SOT1 (eyes open, fixed support surface and surround; SOT2) eyes closed, fixed support surface and surround; and SOT5) eyes closed, sway-referenced support surface, and fixed surround. To compare the demographic and clinical aspects between groups, independent t-test or Mann-Whitney's U-test were used. Differences were found between groups. Between SOT conditions, for CG and RA, COP was faster for SOT-5 than SOT-1, while SOT-1 and SOT-2 presented similar COP velocity. For SOT-2 and SOT-5, COP was larger for the RA group. For both groups, SOT-1 presented the smallest COP, and SOT-5 showed the largest COP.

Sensory Reliance And Visual Fixation In Individuals With And Without Multiple Ankle Sprains

Individuals with a history of multiple ankle sprains (IMAS) present rigid movement patterns contributing to postural instability. Evidence indicates that IMAS upregulate reliance on visual feedback as a compensatory mechanism for postural stability. Increased visual reliance may require IMAS to fixate gaze (visual fixation) on fewer objects. However, how vision is utilized with IMAS while performing static and dynamic tasks compared to healthy controls is unknown. PURPOSE: To validate differences in visual reliance and examine visual fixation while controlling posture in injured-limb in individuals with and without MAS. We hypothesized that IMAS will upregulate visual reliance and increase visual fixation while maintaining posture in injured-limb compared to healthy controls. METHODS: Ten physically active individuals with and without MAS completed the Sensory Organization Test (SOT) to compute sensory ratios that measure reliance on primary sensory systems (somatosensory, visual, vestibular) during postural control. The SOT comprises six conditions to challenge somatosensory, visual, and vestibular feedback in a combination of the sway-referenced support surface and visual surroundings with and without vision. Healthy controls were matched to IMAS and assigned an injured-limb. Visual fixation was measured with gaze fixation count using EyeNal software. One-way repeated measures ANOVA (alpha = .05) and Cohen’s d effect size (ES) analyzed group comparisons. RESULTS: IMAS significantly upregulated vestibular reliance compared to healthy controls (IMAS = .78 ± .02, Healthy = .68 ± .09, ES = 1.44, P = .037), and a large ES was found on visual reliance (IMAS = .96 ± .02, Healthy = .93 ± .05, ES = .79) while controlling posture in injured-limb. No significant group differences were found for visual fixation (P > .05). However, a large ES was found for visual fixation for the SOT condition 1 where all three sensory feedback was intact (IMAS = 14 ± 7.80, Healthy = 21 ± 9.73, ES = .79). CONCLUSIONS: The preliminary results partially confirmed our hypothesis. IMAS upregulated vestibular reliance to aid visual feedback to control posture. Increased visual fixation in IMAS may be indicative of limiting gaze boundaries to obtain accurate visual feedback, but a larger sample size is necessary to confirm our hypothesis.

Equilibrium and Vestibular Safety of Modafinil in Healthy Volunteers.

BACKGROUND: Modafinil, as a wake-promoting agent, is commonly used to relieve fatigue during military operations. However, there is a lack of clarity regarding the effects of modafinil on the equilibrium and vestibular organs, especially when prescribing this drug to flight crewmembers. The objective of this study was to evaluate the equilibrium- and vestibular-related safety effects of modafinil.METHODS: In a randomized, double-blind, placebo-controlled, crossover study, 10 healthy male volunteers received a single 200-mg oral dose of modafinil or placebo. Equilibrium and vestibular functions were assessed 2 h after oral administration by the sensory organization test (SOT), adaptation test (ADT), and video head impulse test (v-HIT).RESULTS: There was no change in the equilibrium scores of the six SOT conditions or the composite scores between the modafinil and placebo groups. Statistically significant differences were not observed for the sway energy score (SES) in the toe-down test. In the toe-up test, the SES decreased by 16.7% in the modafinil group relative to the placebo group in trial 2, while the differences in other trials were not statistically significant. In the v-HIT, there was no significant difference in the gain of each semicircular canal between the two groups.DISCUSSION: A single 200-mg dose of modafinil did not cause any impairment to vestibular function, equilibrium ability, or adaptive balance response; in fact, modafinil might have a positive effect on adaptation function in healthy volunteers. These findings preliminarily suggest that there is no hidden risk of vestibular dysfunction among aviation employees using modafinil.Liu F, Zhang M, Chen T, Zhai L, Zhang Z, Xue J. Equilibrium and vestibular safety of modafinil in healthy volunteers. Aerosp Med Hum Perform. 2022; 93(6):487-492.

The Relationship Between Measures of Postural Control in Concussion Assessment.

To determine the relationship between postural sway performance during commonly utilized postural control assessments following a concussion, including the modified Balance Error Scoring System (mBESS), concussion balance test (COBALT), and sensory organization test (SOT) in healthy young adults. Twenty participants completed all balance testing. The mBESS conditions included double limb stance, single limb stance, and tandem stance. The COBALT was comprised of yaw plane head shake (HS) and vestibular ocular reflex cancellation conditions performed on firm and foam surfaces. Subjects performed 6 conditions of the SOT (C1-C6), which systematically perturbed sensory inputs. Postural sway performance was measured using a single force plate and quantified as a sway score for the mBESS and COBALT, and an equilibrium score for the SOT. Spearman rank correlations were used to examine the relationship between postural sway performance for each test. There was a moderate positive correlation between mBESS-tandem stance and the HS on foam COBALT condition (r = .643, P = .002). There was a moderate negative correlation between mBESS-double limb stance and SOT-C6 (r = -.512, P = .021), and between mBESS-single limb stance and SOT-C6 (r = -.523, P = .018). The COBALT and SOT demonstrated numerous moderate to good negative correlations (r = -.448 to -.708, P ≤ .05), including a good negative correlation between HS on foam and SOT-C1 (r = -.725, P = .0003). Performance on the mBESS had minimal relationship to performance on the COBALT and SOT, suggesting that the clinical standard may not challenge sensory integration at the same capacity as other tests. All COBALT conditions had fair to good associations to at least 2 SOT conditions, suggesting both assessments are representative of sensory integration. Further investigation of the current clinical approach is warranted as the COBALT may be a clinically feasible test of sensory integration.

Stationary auditory white noise improves postural control in healthy adults: A novel study on head-shaking.

Auditory cues might play a role in postural control. The primary aim of this study was to investigate the association between white noise and head-shake (HS) related changes in postural sway. Fifty healthy adults underwent Synapsys Posturography System (SPS) evaluation. The posturography (PG) evaluation consisted of two protocols: sensory organization test (SOT) and SOT with head-shake (HS) (HS-SOT). The standard SOT protocol of SPS involves a battery of six postural conditions. In the current study, participants underwent only four SOT conditions. The participants were asked to stand barefoot on the SPS platform (static platform and foam). The SOT standing conditions were as follow: (1) firm surface (force platform only) with eyes open (SOT1); (2) firm surface with eyes closed (SOT2); (3) foam surface (which was positioned on the force platform) with eyes open (SOT4); and (4) foam surface with eyes closed (SOT5). For the HS-SOT protocol, we asked the participants to move their heads left and right (i.e., yaw head rotation) in the mentioned SOT conditions. Each postural condition was 10 seconds long. Both SOT and HS-SOT postural conditions were conducted across the two hearing modes of silence and noise. To achieve our aims, comparison of sway parameters between SOT and HS-SOT, and between hearing modes were considered. White noise was associated with a reduction in postural sway. The reduction observed in sway area, sway amplitude, and sway frequency. Moreover, HS significantly increased postural sway in all HS-SOT conditions compared to their SOT equivalents (i.e., HS-SOT1 compared to SOT1, etc.). The presence of white noise was associated with a decrease in the HS-related increase in postural sway. Considering the results, this study adds to the body of literature suggesting that white noise contributes to postural control, and the implications of this for rehabilitation need to be further investigated.

A Comparison of Balance Performance of the Sensory Organization Test to the Head Shake Sensory Organization Test in Healthy Adults

To compare equilibrium scores between computerized dynamic posturography tests of the Sensory Organization Test (SOT) to the Head Shake-Sensory Organization Test (HS-SOT) in healthy adults. Approximately 50% of the brain's pathways are related to vision and many of these pathways are susceptible to injury in concussion. Visual-motor disruptions occur in 65%-90% of concussed patients. These disruptions impair balance and can be measured. The SOT is a computerized postural test that evaluates balance by altering visual, proprioceptive, and vestibular cues. The HS-SOT modifies 2 of the standard SOT conditions by including dynamic head motions that stimulate the semicircular canals within the vestibular system. Participants completed the Dizziness Handicap Inventory, Activities of Balance Confidence Scale, SOT, and HS-SOT in one session. Twenty-five individuals (17 females, 8 males; mean age, 21.08 ± 4.10 years, range, 18-33 years) completed outcome measures and 3 trials of testing. There was a significant difference in mean values between the SOT and the HS-SOT for both condition 2 (t(16) = 3.034, p = 0.008) and 5 (t(16) = 5.706, p < 0.001). Additionally, there was a significant difference in mean values between the SOT and the foam HS-SOT for condition 2 (t(16) = 4.673, p < 0.001) and condition 5 (t(16) = 7.263, p < 0.001). There was not a significant difference in means between the foam and without foam for HS-SOT for condition 2 (t(16) = 1.77, p = 0.095) and condition 5 (t(16) = 1.825, p = 0.087). The HS-SOT may quantify subtle balance deficits and enhance the clinical standard use of the SOT. Unlike the SOT where the head is static, the HS-SOT requires head movements, as if saying no repeatedly at approximately 100°/second as measured by an accelerometer. The HS-SOT may quantify subtle balance deficits and enhance the clinical standard use of the SOT.

Characterization of Postural Sway in Patients With Persistent Postural-Perceptual Dizziness (PPPD) Using Wearable Motion Sensors.

To extend previous investigations of postural control in patients with persistent-postural perceptual dizziness (PPPD). Case-controlled, cross-sectional, observational investigation. Tertiary care center. Fifteen patients with PPPD, 15 control volunteers. Measurement of anterior-posterior (AP) and medial-lateral (ML) sway at the waist using wearable accelerometers during posturography; assessment of reach and gait. Peak-to-peak AP and ML sway displacement on the six conditions of the Sensory Organization Test (SOT); Scores on the SOT, Functional Reach Test (FRT), and Dynamic Gait Index (DGI). Compared to control volunteers, patients with PPPD had significantly greater sway displacement at the waist in the AP direction in SOT conditions 3, 5, and 6 and in the ML direction in SOT conditions 2 and 4, resulting in significantly lower median equilibrium scores on the composite index and all six SOT conditions. Patients with PPPD had significantly lower scores on the FRT and DGI that were not correlated with SOT performance. AP sway in conditions 3 and 6 differentiated patients with PPPD from controls with high sensitivity (≥0.87) and specificity (≥0.87). This study replicated previous work showing poor SOT performance by patients with PPPD who had greater AP sway associated with visual dependence and greater ML sway in low demand conditions than controls. Patients with PPPD also performed poorer on the FRT and DGI, but lack of correlation with SOT scores suggested different mechanisms of impairment in postural control, reach, and ambulation. AP sway demonstrated potential as a diagnostic marker.

Sensory Organization Test Conditions Influence Postural Strategy Rather than Footwear or Workload.

Background: Postural strategies such as ankle, hip, or combined ankle-hip strategies are used to maintain optimal postural stability, which can be influenced by the footwear type and physiological workload. Purpose: This paper reports previously unreported postural strategy scores during the six conditions of the sensory organization test (SOT). Methods: Fourteen healthy males (age: 23.6 ± 1.2 years; height: 181 ± 5.3 cm; mass: 89.2 ± 14.6 kg) were tested for postural strategy adopted during SOT in three types of occupational footwear (steel-toed work boot, tactical work boot, low-top work shoe) every 30 min during a 4-h simulated occupational workload. Postural strategy scores were analyzed using repeated measures analysis of variance at 0.05 alpha level. Results: Significant differences among postural strategy scores were only evident between SOT conditions, and but not between footwear type or the workload. Conclusions: Findings indicate that occupational footwear and occupational workload did not cause a significant change in reliance on postural strategies. The significant changes in postural strategy scores were due to the availability of accurate and/or conflicting sensory feedback during SOT conditions. In SOT conditions where all three types of sensory feedback was available, the ankle strategy was predominantly adopted, while more reliance on hip strategy occurred in conditions with absent or conflicting sensory feedback.

Role of Occupational Footwear and Prolonged Walking on Lower Extremity Muscle Activation during Maximal Exertions and Postural Stability Tasks

Background: Occupational footwear and a prolonged duration of walking have been previously reported to play a role in maintaining postural stability. The purpose of this paper was to analyze the impact of three types of occupational footwear: the steel-toed work boot (ST), the tactical work boot (TB), and the low-top work shoe (LT) on previously unreported lower extremity muscle activity during postural stability tasks. Methods: Electromyography (EMG) muscle activity was measured from four lower extremity muscles (vastus medialis (VM), medial hamstrings (MH), tibialis anterior (TA), and medial gastrocnemius (MG) during maximal voluntary isometric contractions (MVIC) and during a sensory organization test (SOT) every 30 min over a 4 h simulated workload while wearing ST, TB, and LT footwear. The mean MVIC and the mean and percentage MVIC during each SOT condition from each muscle was analyzed individually using a repeated measures ANOVA at an alpha level of 0.05. Results: Significant differences (p &lt; 0.05) were found for maximal exertions, but this was limited to only the time main effect. No significant differences existed for EMG measures during the SOT. Conclusion: The findings suggest that occupational footwear type does not influence lower extremity muscle activity during both MVIC and SOT. Significantly lower muscle activity during maximal exertions over the course of the 4 h workload was evident, which can be attributed to localized muscular fatigue, but this was not sufficient to impact muscle activity during postural stability tasks.

The influence of cognitive tasks on sensory organization test performance

IntroductionMany static postural tasks requiring vestibular contributions are completed while dual- tasking. ObjectiveWe investigated the influence of dual-tasks on sensory integration for postural control and cognitive performance during the sensory organization test and examined the relationship between cognitive function and dual-task cost during the sensory organization test. MethodsTwenty adults completed single and dual-task versions of the six conditions of the sensory organization test were completed during two visits separated by one week. A subset of 13 participants completed three National Institute of Health (NIH)-toolbox cognitive tests including the Flanker inhibitory control and attention test, dimensional change card sort test and pattern comparison processing speed test. Wilcoxon signed rank tests were used to compare postural sway during single and dual-task sensory organization test. Friedman’s test, with pairwise comparison post-hoc tests, was used to compare single task serial subtraction performance to the 6 dual-task sensory organization test conditions. Spearman’s correlation coefficients were used to assess the relationship between cognitive performance on NIH-toolbox test and postural and cognitive dual-task cost during the sensory organization test. ResultsPerforming a cognitive dual-task during the sensory organization test resulted in a significant increase in postural sway during condition 1 (Z=−3.26, p=0.001, ES=0.73), condition 3 (Z=−2.53, p=0.012, ES=0.56), and condition 6 (Z=−2.02, p=0.044, ES=0.45). Subtraction performance significantly decreased in during condition 6 (Z=−2.479, p=0.011, ES=0.55) compared to single-task. The dimensional change card sort test demonstrated moderate correlations with dual-task cost of serial subtraction performance in condition 5 (dimensional change card sort test: r=−0.62, p=0.02) and condition 6 (dimensional change card sort test: r=−0.56, p=0.04). Pattern comparison processing speed test scores were significantly correlated with dual-task cost of postural control during condition 2. ConclusionPerforming a cognitive task during the sensory organization test resulted in significantly increased postural sway during three conditions, particularly during visual environment manipulation oppose to vestibular and somatosensory manipulation. Cognitive performance decreased during the most complex sensory organization test condition. Additionally, we found participants with poorer executive function had greater dual-task cost during more complex sensory integration demands.

A block randomised controlled trial investigating changes in postural control following a personalised 12-week exercise programme for individuals with lower limb amputation

BackgroundIndividuals with a lower limb amputation (LLA) have an increased risk of falls and often report lower balance confidence. They must compensate for altered mechanics and prosthetic limitations in order to execute appropriate motor responses to postural perturbations. Personalised exercise could be an effective strategy to enhance balance and reduce falls. Research questionIn this study, we investigated whether a personalised exercise programme could improve postural control and self-reported balance confidence in individuals with an LLA. MethodsParticipants were block randomised into two groups (exercise, n = 7; control, n = 7) based on age and level of amputation. The exercise group completed a 12-week personalised exercise programme, including home-based exercise sessions, consisting of balance, endurance, strength, and flexibility training. The control group continued with their normal daily activities. All participants performed the Sensory Organization Test (SOT) and Motor Control Test (MCT) on the NeuroCom SMART Equitest, and completed the Activities-specific Balance Confidence-UK (ABC) self-report questionnaire, at baseline and post-intervention. Results and significanceExercise group equilibrium scores improved significantly when standing on an unstable support surface with no visual input and inaccurate somatosensory feedback (SOT condition 5, P < 0.012, d = 1.45). There were significant group*time interactions for medium (P = 0.029) and large (P = 0.048) support surface forward translations, which were associated with a trend towards increased weight-bearing on the intact limb in the control group (medium: P = 0.055; large: P = 0.087). No significant changes in ABC score were observed. These results indicate reduced reliance on visual input, and/or enhanced interpretation of somatosensory input, following an exercise programme. However, objective improvements in aspects of postural control were not associated with subjective improvements in self-reported balance confidence. More weight-bearing asymmetry in the control group suggests that a lack of targeted exercise training may have detrimental effects, with potential adverse long-term musculoskeletal consequences, that were quantifiable within a short timeframe.

Changes in the Sensory Weighting Strategies in Balance Control Throughout Maturation in Children.

The central nervous system integrates information from different sensory inputs (vestibular, visual, and somatosensory) to maintain balance. However, strategies for weighing sensory information change as maturation occurs. The purpose of this study was to: (1) evaluate postural control development in a large sample of healthy children aged 5 to 17 years old, (2) analyze changes in sensory weighting strategies as maturation occurs, and (3) determine the extent to which anthropometric characteristics (height, weight, body mass index [BMI]) influence postural control. This study recruited 120 healthy children, equally distributed in gender and number, into four age groups (5-8 years, 9-11 years, 12-14 years, and 15-17 years) and compared them to a control group of 20 healthy adults (aged 20-25 years). The sensory organization test (SOT) was used to assess overall balance and the use of specific sensory inputs to maintain postural control. All children underwent the six SOT conditions: (1) eyes open, surround and platform stable, (2) eyes closed, surround and platform stable, (3) eyes open, sway-referenced surround, platform stable, (4) eyes open, sway-referenced platform, (5) eyes closed, sway-referenced platform, and (6) eyes open, sway-referenced surround and platform. Condition-specific equilibrium scores (ES), composite equilibrium scores (CES), and sensory analysis ratios were analyzed to determine whether the performance was related to age, gender, or specific anthropometric characteristics (height, weight, and BMI). Data showed a significant age-associated improvement in ES for all 6 conditions (p < 0.05) and in CES (p = 0.001). For both genders, (1) somatosensory function was adult-like by age 5 to 8 years, (2) visual function peaked around age 12 years, and (3) vestibular function reached maturity by age 15 to 17 years (p < 0.05). A moderate positive correlation (r(140) = 0.684, p = 0.01; two-tailed) between height and CES was found and a weak positive correlation (r(140) = 0.198, p = 0.01) between height and somatosensory ratio was noted. Lower vestibular ratio scores were observed in children who had a higher BMI (p = 0.001). The efficient use of individual sensory system input to maintain balance does not occur at the same age. Age and gender affect the changes in sensory weighting strategies, while height and BMI influence postural control in children. These factors need to be accounted for in child assessment.

Investigation of the effects of cognitive tasks on balance performance in young adults.

IntroductionIndividuals routinely perform cognitive tasks concurrent to balance functions. The attention is one of the most important cognitive functions and it has effects on vestibular system. This study aims to investigate the connection between balance and cognitive tasks under different conditions.MethodsVisual attention tasks (VAT) and auditory attention tasks (AAT) were given to 30 healthy adults (40.42 ± 11.22 years) during functional balance tasks. Sensory Organization Test (SOT) and Adaptation Test (ADT) were used for the evaluation of postural stability and adaptation. The sounds were presented from the computer speakers in AATs, and VATs were presented in the virtual reality (VR) environment.ResultsThe first SOT condition had a statistically significant difference between all dual VAT (DT-VAT) and single task (ST) (p < 0.001), but there was no statistically significant difference between ST and DT-AAT (p = 1.00). In the fourth SOT condition, there was a statistically significant difference between all DT-VATs versus ST and DT-VA (p < 0.001); there was no statistically significant difference between ST and DT-AA scores (p = 0.80). While there was a significant difference between DT-VA and ST and DT-AA (p < 0.001), no statistically significant difference was observed between ST and DT-AA in the ADT (p = 0.321).ConclusionsBalance performance gets worse with VAT in a VR environment. VR technology can be used to effectively evaluate balance and cognitive performance. The use of experimental environments in standard postural evaluations increases the efficiency of the postural stability tests.

Effect of Mental Fatigue on Postural Sway in Healthy Older Adults and Stroke Populations.

The aim of this study was to examine the effect of mental fatigue on postural sway under different sensory conditions in healthy older adults and in persons with chronic stroke (PwCS). Thirty healthy older adults (> 60 years old), randomly separated into experimental and control groups, as well as 15 PwCS participated in this study. Experimental groups were asked to stand on a force platform wearing seven inertial sensors while performing the Sensory Organization Test (SOT) under two cognitive conditions (single- and dual-task) before and after a mental fatigue task (stop-signal task for 60 min). The control group performed the same protocol before and after watching a movie for 60 min. Changes in subjective fatigue was assessed by the NASA Task Load Index and psychophysiological workload was assessed by heart rate variability (HRV). Postural sway was assessed by calculating the Jerk and root mean square (RMS) of center of mass (COM). Higher Jerk and RMS of COM (p < 0.05) were observed after the mental fatigue task in both healthy older adults and PwCS during SOT, which was not observed in the control group (p > 0.05). Additionally, postural sway increased in the three groups as the SOT conditions became more challenging. Our results indicate that mental fatigue, induced by sustained cognitive activity, can impair balance during SOT in older adult and stroke populations.