scholarly journals Revealing posturographic profile of patients with Parkinsonian syndromes through a novel hypothesis testing framework based on machine learning

PLoS ONE ◽  
2021 ◽  
Vol 16 (2) ◽  
pp. e0246790
Author(s):  
Ioannis Bargiotas ◽  
Argyris Kalogeratos ◽  
Myrto Limnios ◽  
Pierre-Paul Vidal ◽  
Damien Ricard ◽  
...  
Keyword(s):  
Machine Learning ◽  
Multiple Testing ◽  
Center Of Pressure ◽  
Statistical Tests ◽  
Natural Extension ◽  
Parkinsonian Syndromes ◽  
Eyes Closed ◽  
Classical Statistics ◽  
Significant Difference ◽  
Eyes Open

Falling in Parkinsonian syndromes (PS) is associated with postural instability and consists a common cause of disability among PS patients. Current posturographic practices record the body’s center-of-pressure displacement (statokinesigram) while the patient stands on a force platform. Statokinesigrams, after appropriate processing, can offer numerous posturographic features. This fact, although beneficial, challenges the efforts for valid statistics via standard univariate approaches. In this work, 123 PS patients were classified into fallers (PSF) or non-faller (PSNF) based on the clinical assessment, and underwent simple Romberg Test (eyes open/eyes closed). We developed a non-parametric multivariate two-sample test (ts-AUC) based on machine learning, in order to examine statokinesigrams’ differences between PSF and PSNF. We analyzed posturographic features using both multiple testing with p-value adjustment and ts-AUC. While ts-AUC showed significant difference between groups (p-value = 0.01), multiple testing did not agree with this result (eyes open). PSF showed significantly increased antero-posterior movements as well as increased posturographic area compared to PSNF. Our study highlights the superiority of ts-AUC compared to standard statistical tools in distinguishing PSF and PSNF in multidimensional space. Machine learning-based statistical tests can be seen as a natural extension of classical statistics and should be considered, especially when dealing with multifactorial assessments.

scholarly journals Static Balance in Patients with Vestibular Impairments: A Preliminary Study

Scientifica ◽  
2016 ◽  
Vol 2016 ◽  
pp. 1-4 ◽  
Author(s):  
Hossein Talebi ◽  
Mohammad Taghi Karimi ◽  
Seyed Hamid Reza Abtahi ◽  
Niloofar Fereshtenejad
Keyword(s):  
Path Length ◽  
Center Of Pressure ◽  
Balance Control ◽  
Force Plate ◽  
Static Balance ◽  
Eyes Closed ◽  
Significant Difference ◽  
Eyes Open ◽  
Age Limits ◽  
The Difference

Aims. Vestibular system is indicated as one of the most important sensors responsible for static and dynamic postural control. In this study, we evaluated static balance in patients with unilateral vestibular impairments.Materials and Methods. We compared static balance control using Kistler force plate platform between 10 patients with unilateral vestibular impairments and 20 normal counterparts in the same sex ratio and age limits (50±7). We evaluated excursion and velocity of center of pressure (COP) and path length in anteroposterior (AP) and mediolateral (ML) planes with eyes open and with eyes closed.Results. There was no significant difference between COP excursions in ML and AP planes between both groups with eyes open and eyes closed (pvalue > 0.05). In contrast, the difference between velocity and path length of COP in the mentioned planes was significant between both groups with eyes open and eyes closed (pvalue < 0.05).Conclusions. The present study showed the static instability and balance of patients with vestibular impairments indicated by the abnormal characteristics of body balance.

scholarly journals Balance Performance With and Without Visual Information: A Comparison of Elite Players With Chronic Ankle Instability

2019 ◽  
Vol 11 (2) ◽  
pp. 125-132
Author(s):  
Zahra Raeisi ◽  
◽  
Ali Yalfani ◽  
Keyword(s):  
Visual Information ◽  
Center Of Pressure ◽  
Ankle Instability ◽  
Chronic Ankle Instability ◽  
Balance Performance ◽  
Balance Test ◽  
Eyes Closed ◽  
Significant Difference ◽  
Volleyball Players ◽  
Eyes Open

Introduction: This research was conducted to determine whether professional athletes with Chronic Ankle Instability (CAI) exhibit differences in maintaining balance under conditions of with and without visual information Materials and Methods: Forty-five elite players with CAI were classified into soccer, volleyball, and basketball groups (n=15 each). All participants performed a static single-leg balance test in conditions wherein visual information was provided and withheld. Also, their center of pressure (CoP) oscillation parameters was measured. The data were examined through an analysis of variance (ANOVA) and the Tukey test. Results: A significant difference was found between the soccer and volleyball players (P=0.034) in anteroposterior CoP displacement. Furthermore, there was a significant difference between soccer compared with volleyball (P=0.001) and basketball (P=0.02) groups regarding mediolateral sway and sway area (P=0.003 and P=0.03, respectively) when they performed the test with their eyes open. A significant difference occurred between the soccer and volleyball players concerning anteroposterior and mediolateral sway (P=0.002 and P=0.04, respectively) and sway area (P=0.004) when they performed the test with their eyes closed. Conclusion: Given the necessity of maintaining a good balance in sports, volleyball coaches should design practices that reduce players’ reliance on visual information. These practices should strengthen their proprioceptive abilities through an increased challenge to their proprioceptive senses.

A systematic review and meta-analysis on efficacy of exercise on posture and balance in patients suffering from Diabetic Neuropathy

2020 ◽  
Vol 16 ◽  
Author(s):  
Neerja Thukral ◽  
Jaspreet Kaur ◽  
Manoj Malik
Keyword(s):  
Diabetes Mellitus ◽  
Diabetic Neuropathy ◽  
Meta Analysis ◽  
Berg Balance Scale ◽  
Risk Of Bias ◽  
Core Stability ◽  
Balance Scale ◽  
Eyes Closed ◽  
Significant Difference ◽  
Eyes Open

Background: Peripheral neuropathy is a major and chronic complication of diabetes mellitus affecting more than 50% of patients suffering from diabetes. There is involvement of both large and small diameter nerve fibres leading to altered somatosensory and motor sensations, thereby causing impaired balance and postural instability. Objective: To assess the effects of exercises on posture and balance in patients suffering from diabetes mellitus. Method: Mean changes in Timed Up and Go test(TUGT), Berg Balance Scale and Postural Sway with eyes open and eyes closed on Balance System were primary outcome measures. RevMan 5.3 software was used for the meta-analyses. Eighteen randomized controlled trials met the selection criteria and were included in the study. All the studies ranked high on PEDro Rating scale. Risk of bias was assessed by Cochrane collaboration tool of risk of bias. Included studies had low risk of bias. Sixteen RCT’s were included for the meta-analysis. Result: Results of meta-analysis showed that there was statistically significant improvement in TUGT with p≤ 0.05 and substantial heterogeneity (I 2 = 84%, p < 0.00001) in experimental group as compared to control group. There was statistically significant difference in Berg Balance Scale scores and heterogeneity of I 2 = 62%, p < 0.00001 and significant changes in postural stability (eyes open heterogeneity of I 2 = 100%, p =0.01 and eyes closed, heteogeneity I 2 = 0%, p =0.01). Sensitivity analysis causes change in heterogeneity. Conclusion: It can be concluded that various exercises like balance training, core stability, Tai-Chi, proprioceptive training etc. have a significant effect in improving balance and posture in diabetic neuropathy.

Assessing head acceleration to identify a motor threshold to galvanic vestibular stimulation

2021 ◽  
Author(s):  
Youstina Mikhail ◽  
Jonathan Charron ◽  
Jean-Marc Mac Thiong ◽  
Dorothy Barthélemy
Keyword(s):  
Center Of Pressure ◽  
Vestibular Function ◽  
Vestibular Stimulation ◽  
Galvanic Vestibular Stimulation ◽  
Head Acceleration ◽  
Motor Threshold ◽  
Recruitment Curve ◽  
Eyes Closed ◽  
Postural Responses ◽  
Significant Difference

Galvanic vestibular stimulation (GVS) is used to assess vestibular function, but vestibular responses can exhibit variability depending on protocols or intensities used. We measured head acceleration in healthy subjects to identify an objective motor threshold on which to base GVS intensity when assessing postural responses. Thirteen healthy right-handed subjects stood on a force platform, eyes closed, head facing forward. An accelerometer was placed on the vertex to detect head acceleration, and electromyography activity of the right soleus was recorded. GVS (200 ms; current steps 0.5;1-4mA) was applied in a binaural and bipolar configuration. 1) GVS induced a biphasic accelerometer response at a latency of 15 ms. Based on response amplitude, we constructed a recruitment curve for all participants and determined the motor threshold. In parallel, the method of limits was used to devise a more rapid approach to determine motor threshold. 2) We observed significant differences between motor threshold based on therecruitment curve and perceptual thresholds (sensation/perception of movement). No significant difference was observed between the motor threshold based on the method of limits and perceptual thresholds . 3) Using orthogonal polynomial contrasts, we observed a linear progression between multiples of the objective motor threshold (0.5, 0.75, 1, 1.5x motor threshold) and the 95% confidence ellipse area, the first peak of center of pressure velocity, and the short and medium latency responses in the soleus. Hence, an objective motor threshold and a recruitment curve for GVS were determined based on head acceleration, which could increase understanding of the vestibular system.

Effect of transcendental meditation on breathing and respiratory control

1984 ◽  
Vol 56 (3) ◽  
pp. 607-612 ◽  
Author(s):  
N. Wolkove ◽  
H. Kreisman ◽  
D. Darragh ◽  
C. Cohen ◽  
H. Frank
Keyword(s):  
Transcendental Meditation ◽  
Minute Ventilation ◽  
Respiratory Control ◽  
Respiratory Pattern ◽  
Quiet Breathing ◽  
The Unconscious ◽  
Eyes Closed ◽  
Significant Difference ◽  
Regulation Of Breathing ◽  
Eyes Open

We studied the effect of transcendental meditation (TM) on breathing using 16 experienced meditators and 16 control subjects. In controls, there was no significant difference in minute ventilation (VE), respiratory pattern, or hypercapnic response, whether breathing with eyes open-awake (CA), or with eyes closed-relaxing (CR). In meditators, VE decreased significantly during quiet breathing from 14.0 +/- 0.7 1/min with eyes open-awake (MA) to 12.4 +/- 0.6 1/min during meditation (MM) (P less than 0.02). The change in VE during meditation was due to a decrease in tidal volume (VT) resulting from a shortened inspiratory time (TI). Meditation was associated with a decreased response to progressive hypercapnia from 3.7 +/- 0.4 to 2.5 +/- 0.21 X min-1 X Torr-1 during MA and MM trials, respectively (P less than 0.01). During meditation VT was smaller at a given alveolar PCO2 than during MA studies because of a decrease in mean inspiratory flow rate (VT/TI). These observations suggest that an alteration in wakefulness, more subtle than sleep or the unconscious state, can significantly affect the chemical and neural regulation of breathing.

scholarly journals The influence of an aquatic exercise program on balance in patients with ankylosing spondylitis

2021 ◽  
Vol 31 (Supplement_2) ◽  
Author(s):  
Margarida Ferreira ◽  
Cristina Mesquita ◽  
Paula Santos ◽  
João Borges ◽  
Maria Graça ◽  
...  
Keyword(s):  
Ankylosing Spondylitis ◽  
Center Of Pressure ◽  
Exercise Program ◽  
Wilcoxon Test ◽  
Aquatic Exercise ◽  
Body Sway ◽  
Mean Velocity ◽  
Assessment Protocol ◽  
Eyes Closed ◽  
Eyes Open

Abstract Background Ankylosing spondylitis (AS) is a chronic inflammatory rheumatic disease that leads to a limitation of mobility, which can cause postural deficits and progressive loss of balance. Aquatic exercise improves this health condition. The objetive is to verify the influence of an aquatic exercise program, on balance and functionality, in individuals with AS. Methods Pre-experimental study carried out on 6 individuals with AS. All individuals were assessed at baseline (M0) and 12 weeks after the intervention (M1) using the Bath indices (BASMI, BASFI and BASDAI) and the balance assessment protocol (‘Body Sway’) by the Physiosensing Platform. Data were analyzed using the Statistical Program Statistical Package for the Social Sciences (SPSS), version 26. Were used descriptive statistics and Wilcoxon test to compare M0 and M1. The significance value was 0.05. Results We verify improvements in BASMI (P = 0.046), BASFI (P = 0.042) and BASDAI (P = 0.027) scores. Through the analysis of the center of pressure variables, there were no statistically significant differences, between moments, in the protocol. However, when assessing balance, in the anteroposterior mean distance in both the protocol (eyes open) and in the protocol (eyes closed), in the root mean square in both protocols and in mediolateral mean velocity, only in the protocol (eyes open), there was a slight decrease in the median value. Conclusions The present study suggests that the specific aquatic exercise program, may influence balance and improve functionality in a population with AS. Therefore, the Bath indices translate improvements in the symptoms and functionalities of these participants.

scholarly journals Maximal stability limits in adolescents with Tourette syndrome

2021 ◽  
Vol 4 (1) ◽  
pp. 013-022
Author(s):  
Blanchet Mariève ◽  
Prince François ◽  
Lemay Martin ◽  
Chouinard Sylvain ◽  
Messier Julie
Keyword(s):  
Postural Control ◽  
Tourette Syndrome ◽  
Center Of Pressure ◽  
Phase 1 ◽  
Sensory Information ◽  
Control Group ◽  
Eyes Closed ◽  
Highly Sensitive ◽  
Eyes Open ◽  
Stability Limits

We explored if adolescents with Gilles de la Tourette syndrome (GTS) had functional postural control impairments and how these deficits are linked to a disturbance in the processing and integration of sensory information. We evaluated the displacements of the center of pressure (COP) during maximal leaning in four directions (forward, backward, rightward, leftward) and under three sensory conditions (eyes open, eyes closed, eyes closed standing on foam). GTS adolescents showed deficits in postural stability and in lateral postural adjustments but they had similar maximal COP excursion than the control group. The postural performance of the GTS group was poorer in the eyes open condition (time to phase 1 onset, max-mean COP). Moreover, they displayed a poorer ability to maintain the maximum leaning position under the eyes open condition during mediolateral leaning tasks. By contrast, during forward leaning, they showed larger min-max ranges than control subjects while standing on the foam with the eyes closed. Together, these findings support the idea that GTS produces subclinical postural control deficits. Importantly, our results suggest that postural control disorders in GTS are highly sensitive to voluntary postural leaning tasks which have high demand for multimodal sensory integration.

scholarly journals Increased signal diversity/complexity of spontaneous EEG, but not evoked EEG responses, in ketamine-induced psychedelic state in humans

2019 ◽  
Author(s):  
Nadine Farnes ◽  
Bjørn E. Juel ◽  
André S. Nilsen ◽  
Luis G. Romundstad ◽  
Johan F. Storm
Keyword(s):  
Brain Activity ◽  
Altered States Of Consciousness ◽  
Altered States ◽  
Eeg Signal ◽  
Eyes Closed ◽  
Electrical Brain Activity ◽  
States Of Consciousness ◽  
Significant Difference ◽  
Eyes Open ◽  
Signal Diversity

AbstractObjectiveHow and to what extent electrical brain activity is affected in pharmacologically altered states of consciousness, where it is mainly the phenomenological content rather than the level of consciousness that is altered, is not well understood. An example is the moderately psychedelic state caused by low doses of ketamine. Therefore, we investigated whether and how measures of evoked and spontaneous electroencephalographic (EEG) signal diversity are altered by sub-anaesthetic levels of ketamine compared to normal wakefulness, and how these measures relate to subjective assessments of consciousness.MethodsHigh-density electroencephalography (EEG, 62 channels) was used to record spontaneous brain activity and responses evoked by transcranial magnetic stimulation (TMS) in 10 healthy volunteers before and after administration of sub-anaesthetic doses of ketamine in an open-label within-subject design. Evoked signal diversity was assessed using the perturbational complexity index (PCI), calculated from the global EEG responses to local TMS perturbations. Signal diversity of spontaneous EEG, with eyes open and eyes closed, was assessed by Lempel Ziv complexity (LZc), amplitude coalition entropy (ACE), and synchrony coalition entropy (SCE).ResultsAlthough no significant difference was found in the index of TMS-evoked complexity (PCI) between the sub-anaesthetic ketamine condition and normal wakefulness, all the three measures of spontaneous EEG signal diversity showed significantly increased values in the sub-anaesthetic ketamine condition. This increase in signal diversity also correlated with subjective assessment of altered states of consciousness. Moreover, spontaneous signal diversity was significantly higher when participants had eyes open compared to eyes closed, both during normal wakefulness and during influence of sub-anaesthetic ketamine doses.ConclusionThe results suggest that PCI and spontaneous signal diversity may be complementary and potentially measure different aspects of consciousness. Thus, our results seem compatible with PCI being indicative of the brain’s ability to sustain consciousness, as indicated by previous research, while it is possible that spontaneous EEG signal diversity may be indicative of the complexity of conscious content. The observed sensitivity of the latter measures to visual input seems to support such an interpretation. Thus, sub-anaesthetic ketamine may increase the complexity of both the conscious content (experience) and the brain activity underlying it, while the level, degree, or general capacity of consciousness remains largely unaffected.

Static Postural Control Deficits in Adults with Myotonic Dystrophy Type 1, Steinert Disease

2022 ◽  
pp. 1-10
Author(s):  
Audrey Parent ◽  
Laurent Ballaz ◽  
Bahare Samadi ◽  
Maria Vocos, pht ◽  
Alain Steve Comtois ◽  
...  
Keyword(s):  
Postural Control ◽  
Myotonic Dystrophy ◽  
Myotonic Dystrophy Type 1 ◽  
Myotonic Dystrophy Type ◽  
Control Performance ◽  
Significant Group ◽  
Eyes Closed ◽  
Significant Difference ◽  
Eyes Open

Background: Myotonic dystrophy type 1 (DM1) is characterized by progressive and predominantly distal muscle atrophy and myotonia. Gait and balance impairments, resulting in falls, are frequently reported in this population. However, the extent to which individuals with DM1 rely more on a specific sensory system for balance than asymptomatic individuals (AI) is unknown. Objective: Evaluate postural control performance in individuals with DM1 and its dependence on vision compared to AI. Methods: 20 participants with DM1, divided into two groups based on their diagnosis, i.e. adult and congenital phenotype, and 12 AI participants were recruited. Quiet standing postural control was assessed in two visual conditions: eyes-open and eyes-closed. The outcomes measures were center of pressure (CoP) mean velocity, CoP range of displacement in anteroposterior and mediolateral axis, and the 95% confidence ellipse’s surface. Friedman and Kruskal-Wallis analysis of variance were used to compare outcomes between conditions and groups, respectively. Results: Significant group effect and condition effect were observed on postural control performance. No significant difference was observed between the two DM1 groups. The significant differences observed between the AI group and the two DM1 groups in the eyes-open condition were also observed in the eyes-closed condition. Conclusions: The result revealed poorer postural control performance in people with DM1 compared to AI. The DM1 group also showed similar decrease in performance than AI in eyes-closed condition, suggesting no excessive visual dependency.

Reliability of Force-Platform Measures of Postural Sway and Expertise-Related Differences

2011 ◽  
Vol 20 (4) ◽  
pp. 442-456 ◽  
Author(s):  
Zohreh Meshkati ◽  
Mehdi Namazizadeh ◽  
Mahyar Salavati ◽  
Masood Mazaheri
Keyword(s):  
Outcome Measures ◽  
Postural Sway ◽  
Center Of Pressure ◽  
Intraclass Correlation ◽  
Specific Property ◽  
Force Platform ◽  
Quiet Standing ◽  
Eyes Closed ◽  
Before And After ◽  
Eyes Open

Context:Although reliability is a population-specific property, few studies have investigated the measurement error associated with force-platform parameters in athletic populations.Objective:To investigate the skill-related differences between athletes and nonathletes in reliability of center-of-pressure (COP) summary measures under eyes-open (EO) and eyes-closed (EC) conditions.Design:Test–retest reliability study.Setting:COP was recorded during double-leg quiet standing on a Kistler force platform before and after a fatiguing treadmill exercise, with EO and EC.Participants:31 male participants including 15 athletes practiced in karate and 16 nonathletes.Main Outcome Measures:Standard deviation (SD) of amplitude, phase-plane portrait, SD of velocity, mean total velocity, and area were calculated from 30-s COP data. Intraclass correlation coefficient (ICC), standard error of measurement, and coefficient of variation (CV) were used as estimates of reliability and precision.Results:Higher ICCs were found for COP measures in the athlete (compared with the nonathlete) group, postfatigued (compared with prefatigued) condition, and EC (compared with EO) tests. CVs smaller than 15% were obtained for most of the COP measures. SD of velocity in the anteroposterior direction showed the highest reliability in most conditions.Conclusions:Tests with EC and to a lesser extent tests performed in the athlete group and in the postfatigued condition showed better reliability.

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