Relationship between Mental Rotation of Body Parts and Postural Stability during Quiet Stance

2014 ◽  
Vol 9 (1) ◽  
Author(s):  
Tsubasa Kawasaki ◽  
Kazuhiro Yasuda ◽  
Kazunobu Fukuhara ◽  
Takahiro Higuchi
Keyword(s):  
Reaction Time ◽  
Mental Rotation ◽  
Postural Stability ◽  
Postural Sway ◽  
Reaction Times ◽  
Body Parts ◽  
Quiet Stance ◽  
Mean Velocity ◽  
Unipedal Standing ◽  
Posterior Direction

AbstractThe present study was designed to investigate a relationship between the ability to quickly perform a mental rotation (MR) task using body (particularly foot) stimuli and postural stability during unipedal and bipedal quiet stance. Twenty-four healthy young adults participated in this study to measure reaction times for the MR (stimuli: foot, hand, and car), postural sway values during unipedal and bipedal standings, and lower extremity functions. Results showed significant correlations between the reaction time for the MR of the foot stimuli (but not for hand and car stimuli) and some of postural sway values (total length of sway and mean velocity in the anterior–posterior direction) during unipedal standing (but not for bipedal standing). Consistently, participants who performed the MR task quickly showed significantly smaller sway values during unipedal standing than those who performed the task slowly. These findings suggest that the ability to mentally imagine the foot movement is likely to relate to postural stability, while involving a challenging postural task, such as unipedal standing. The reaction time for the MR of foot stimuli was also correlated with two-point discrimination (TPD) distance on the plantar skin. Given that the TPD distance not only represents cutaneous acuity but also reflects participants’ body image relating to their feet, MR performance may have been related to postural stability because both involve cognitive processes used for both motor imagery and motor execution of the foot movement.

scholarly journals Postural Sway and Effect of Levodopa in Early Parkinson's Disease

2008 ◽  
Vol 35 (1) ◽  
pp. 65-68 ◽  
Author(s):  
Anne Beuter ◽  
Roberto Hernández ◽  
Robert Rigal ◽  
Julien Modolo ◽  
Pierre J. Blanchet
Keyword(s):  
Parkinson’S Disease ◽  
Parkinson's Disease ◽  
Postural Stability ◽  
Postural Sway ◽  
Stability Control ◽  
Control Mechanisms ◽  
Quiet Stance ◽  
Dependent Variables ◽  
Eyes Open ◽  
Early Parkinson’S Disease

Objective:To characterize postural stability control and levodopa responsiveness in early Parkinson's disease (PD).Methods:Postural sway was studied during quiet stance in ten patients within six years of PD onset, both before (OFF) and after (ON) regular oral levodopa dosing. Postural sway was recorded using a force platform during 30 sec with eyes open, and six dependent variables were examined.Results:Mild baseline subclinical changes in postural sway were recorded in our patients. Clear benefit was observed in five out of six characteristics (mean sway, transversal sway, sagittal sway, sway intensity, and sway area) in the ON condition.Conclusion:Postural control mechanisms are affected early in PD and modulated by dopamine.

VOLUME OF CONVEX HULL: A TECHNIQUE FOR QUANTIFYING HUMAN POSTURAL STABILITY

2016 ◽  
Vol 16 (02) ◽  
pp. 1650013 ◽  
Author(s):  
PATRIK KUTILEK ◽  
ONDREJ CAKRT ◽  
VLADIMIR SOCHA ◽  
KAREL HANA
Keyword(s):  
Convex Hull ◽  
Postural Stability ◽  
Postural Sway ◽  
Balance Control ◽  
The Body ◽  
Quiet Stance ◽  
Body Segments ◽  
3D Space ◽  
Cerebellar Disorder ◽  
Trunk Sway

Many disorders, such as nervous system disorders, can affect orientation of the body segments in 3D space negatively. Patients with these disorders often show body segments instability during stance tasks. Nowadays, 3-axis gyroscopes are about to be used to measure postural stability. The main objective of the paper is to describe a method which would be suitable for quantifying postural stability and 3D movement as a whole using a cheap 3-axis gyroscope. New method based on the volume of a 3D convex hull (CH) obtained by plotting pitch, roll and yaw angles versus each other was proposed for quantitative evaluation of 3D trunk sway. The sway was measured while patients with degenerative cerebellar disorder (Pts) and eleven healthy subjects (HSs) performed quiet stance on a firm surface (FiS) and foam surface (FoS) with open eyes (OE) and closed eyes (CE). The CH was used to identify differences in balance control, and there were significant differences found between the two groups. The median (Mdn) of the volume of Pts with OE on FiS is four times larger than the Mdn of the volume of HS with OE on FiS. The Mdn of the volume of Pts with CE on FoS is 80 times larger than the Mdn of the volume of HS with CE on FoS. It was therefore found that the volume of CH is suitable for quantifying postural sway and identifying differences in balance control.

Utility of a Postural Stability/Perceptual Inhibition Dual Task for Identifying Concussion in Adolescents

2021 ◽  
pp. 1-6
Author(s):  
Shawn R. Eagle ◽  
Patrick J. Sparto ◽  
Cynthia L. Holland ◽  
Abdulaziz A. Alkathiry ◽  
Nicholas A. Blaney ◽  
...  
Keyword(s):  
Logistic Regression ◽  
Reaction Time ◽  
Dual Task ◽  
Postural Stability ◽  
Postural Sway ◽  
Area Under The Curve ◽  
Spatial Discrimination ◽  
Discriminative Ability ◽  
Visual Spatial ◽  
Time Accuracy

Context: Research in the area of dual-task paradigms to assess sport-related concussion (SRC) status is growing, but additional assessment of this paradigm in adolescents is warranted. Design: This case-control study compared 49 adolescent athletes aged 12–20 years with diagnosed SRC to 49 age- and sex-matched controls on visual–spatial discrimination and perceptual inhibition (PIT) reaction time tasks performed while balancing on floor/foam pad conditions. Methods: The SRC group completed measures at a single time point between 1 and 10 days postinjury. Primary outcomes were dual-task reaction time, accuracy, and sway. General linear models evaluated differences between groups (P < .05). Logistic regression identified predictors of concussion from outcomes. Area under the curve evaluated discriminative ability of identifying SRC. Results: Results supported significantly higher anterior–posterior (AP) sway values in concussed participants for visual–spatial discrimination and PIT when balancing on the floor (P = .03) and foam pad (P = .03), as well as mediolateral sway values on the floor during visual–spatial discrimination (P = .01). Logistic regression analysis (R2 = .15; P = .001) of all dual-task outcomes identified AP postural sway during the PIT foam dual task as the only significant predictor of concussed status (ß = −2.4; P = .004). Total symptoms (area under the curve = 0.87; P < .001) and AP postural sway on foam (area under the curve = 0.70; P = .001) differentiated concussed from controls. Conclusion: The AP postural sway on foam during a postural stability/PIT dual task can identify concussion in adolescents between 1 and 10 days from injury.

Limitations of Postural Stability Ratings

2007 ◽  
Vol 51 (18) ◽  
pp. 1219-1223
Author(s):  
Angela DiDomenico ◽  
Krystyna Gielo-Perczak ◽  
Raymond W. McGorry ◽  
Chien-Chi Chang
Keyword(s):  
Construction Industry ◽  
Postural Stability ◽  
Postural Sway ◽  
Subjective Assessment ◽  
Subjective Measures ◽  
Construction Operations ◽  
Mean Velocity ◽  
Foot Placement ◽  
Subjective Perceptions ◽  
The Stability

A substantial number of injuries and fatalities within occupational environments are due to falls, the majority of which are believed to be a result of loss of balance. The construction industry has been identified as one of the most hazardous industries and falls from height are a leading cause of fatalities in construction operations. This study investigated the effects of beam condition, foot placement and load on objective and subjective assessment of postural stability. Twenty-three male participants completed all conditions with the effect of beam condition significantly affecting both objective and subjective measures of stability (ANOVA, α = 0.05). While not significantly affecting postural sway, the load conditions significantly affected the stability ratings. Correlations between the objective and subjective measures were very weak (–0.219 < r < 0.01) with the strongest correlation between mean velocity and the stability ratings. Subjective perceptions of postural stability should be used with caution, particularly in more realistic task environments with less variability in difficulty levels.

An Insole Pressure Measurement System: Repeatability of Postural Data

2000 ◽  
Vol 21 (3) ◽  
pp. 221-226 ◽  
Author(s):  
Jeffrey A. Bauer ◽  
James H. Cauraugh ◽  
Mark D. Tillman
Keyword(s):  
Measurement System ◽  
Pressure Measurement ◽  
Postural Stability ◽  
Postural Sway ◽  
Test Session ◽  
Quiet Stance ◽  
Healthy Individuals ◽  
Pressure Data ◽  
Plantar Pressure Measurement ◽  
Pressure Measurement System

This study analyzed the ability of an in-shoe plantar pressure measurement system to provide repeatable measurements of postural sway data for both healthy and clinical patients. Each participant's in-shoe pressure data were recorded for three trials during each test session during quiet stance. Healthy individuals (n=9) participated on three consecutive days while clinical participants (n=5) were tested on one day. Nine response variables were measured to assess their postural stability. Intra-subject measures were evaluated using the Kerlinger reliability procedure. Values provided directly by the Parotec System® for a single day of testing yielded the following average coefficients: r = 0.95 (left), r = 0.97 (right) with mean coefficient values from the three day tests of: r = 0.98 (left), r = 0.98 (right). Variables calculated from raw data on a single day produced mean coefficients of: r = 0.77 (left), r = 0.76 (right) and over three days of: r = 0.65 (left), r =0.66 (right). The ability to record highly reproducible data of postural sway parameters should assist clinicians to treat patients more confidently for balance deficiencies.

Modeling Within-Person Variance in Reaction Time Data of Older Adults

GeroPsych ◽  
2011 ◽  
Vol 24 (4) ◽  
pp. 169-176 ◽  
Author(s):  
Philippe Rast ◽  
Daniel Zimprich
Keyword(s):  
Reaction Time ◽  
Cognitive Aging ◽  
Reaction Times ◽  
Reaction Time Task ◽  
Reaction Time Data ◽  
Scale Model ◽  
Time Data ◽  
Time Task ◽  
The Mean ◽  
Second Wave

In order to model within-person (WP) variance in a reaction time task, we applied a mixed location scale model using 335 participants from the second wave of the Zurich Longitudinal Study on Cognitive Aging. The age of the respondents and the performance in another reaction time task were used to explain individual differences in the WP variance. To account for larger variances due to slower reaction times, we also used the average of the predicted individual reaction time (RT) as a predictor for the WP variability. Here, the WP variability was a function of the mean. At the same time, older participants were more variable and those with better performance in another RT task were more consistent in their responses.

The Level of Reaction Time Determines the ERP Correlates of Auditory Negative Priming

2006 ◽  
Vol 20 (3) ◽  
pp. 186-194 ◽  
Author(s):  
Susanne Mayr ◽  
Michael Niedeggen ◽  
Axel Buchner ◽  
Guido Orgs
Keyword(s):  
Reaction Time ◽  
Negative Priming ◽  
Effect Size ◽  
Priming Effect ◽  
Reaction Times ◽  
Negative Priming Effect ◽  
Episodic Retrieval ◽  
Time Level ◽  
Fast Reactions ◽  
Priming Condition

Responding to a stimulus that had to be ignored previously is usually slowed-down (negative priming effect). This study investigates the reaction time and ERP effects of the negative priming phenomenon in the auditory domain. Thirty participants had to categorize sounds as musical instruments or animal voices. Reaction times were slowed-down in the negative priming condition relative to two control conditions. This effect was stronger for slow reactions (above intraindividual median) than for fast reactions (below intraindividual median). ERP analysis revealed a parietally located negativity of the negative priming condition compared to the control conditions between 550-730 ms poststimulus. This replicates the findings of Mayr, Niedeggen, Buchner, and Pietrowsky (2003) . The ERP correlate was more pronounced for slow trials (above intraindividual median) than for fast trials (below intraindividual median). The dependency of the negative priming effect size on the reaction time level found in the reaction time analysis as well as in the ERP analysis is consistent with both the inhibition as well as the episodic retrieval account of negative priming. A methodological artifact explanation of this effect-size dependency is discussed and discarded.

The Effect of Retest Practice on the Speed-Ability Relationship

2004 ◽  
Vol 9 (1) ◽  
pp. 24-31 ◽  
Author(s):  
Sybille Rockstroh ◽  
Karl Schweizer
Keyword(s):  
Reaction Time ◽  
Skill Acquisition ◽  
Reaction Times ◽  
Cognitive Tasks ◽  
General Intelligence ◽  
Attention Switching ◽  
Letter Comparison ◽  
Sternberg Paradigm ◽  
The Relationship ◽  
Elementary Cognitive Tasks

Effects of four retest-practice sessions separated by 2 h intervals on the relationship between general intelligence and four reaction time tasks (two memory tests: Sternberg's memory scanning, Posner's letter comparison; and two attention tests: continuous attention, attention switching) were examined in a sample of 83 male participants. Reaction times on all tasks were shortened significantly. The effects were most pronounced with respect to the Posner paradigm and smallest with respect to the Sternberg paradigm. The relationship to general intelligence changed after practice for two reaction time tasks. It increased to significance for continuous attention and decreased for the Posner paradigm. These results indicate that the relationship between psychometric intelligence and elementary cognitive tasks depends on the ability of skill acquisition. In the search for the cognitive roots of intelligence the concept of learning seems to be of importance.

How Useful is the Power Law of Practice for Recognizing Practice in Concentration Tests?

2007 ◽  
Vol 23 (3) ◽  
pp. 157-165 ◽  
Author(s):  
Carmen Hagemeister
Keyword(s):  
Logistic Regression ◽  
Reaction Time ◽  
Power Law ◽  
Error Rate ◽  
Reaction Times ◽  
Practice Effect ◽  
Practice Effects ◽  
Rate Decrease ◽  
Small Practice

Abstract. When concentration tests are completed repeatedly, reaction time and error rate decrease considerably, but the underlying ability does not improve. In order to overcome this validity problem this study aimed to test if the practice effect between tests and within tests can be useful in determining whether persons have already completed this test. The power law of practice postulates that practice effects are greater in unpracticed than in practiced persons. Two experiments were carried out in which the participants completed the same tests at the beginning and at the end of two test sessions set about 3 days apart. In both experiments, the logistic regression could indeed classify persons according to previous practice through the practice effect between the tests at the beginning and at the end of the session, and, less well but still significantly, through the practice effect within the first test of the session. Further analyses showed that the practice effects correlated more highly with the initial performance than was to be expected for mathematical reasons; typically persons with long reaction times have larger practice effects. Thus, small practice effects alone do not allow one to conclude that a person has worked on the test before.

Porous Gel Coatings Obtained by Phase Separation in ORMOSIL System

2000 ◽  
Vol 628 ◽  
Author(s):  
Kazuki Nakanishi ◽  
Souichi Kumon ◽  
Kazuyuki Hirao ◽  
Hiroshi Jinnai
Keyword(s):  
Phase Separation ◽  
Reaction Time ◽  
Volume Fraction ◽  
Sol Gel ◽  
Reaction Times ◽  
Dip Coating ◽  
Coating Solution ◽  
Coating Method ◽  
Gel Phase ◽  
Dip Coating Method

ABSTRACTMacroporous silicate thick films were prepared by a sol-gel dip-coating method accompanied by the phase separation using methyl-trimethoxysilane (MTMS), nitric acid and dimethylformamide (DMF) as starting components. The morphology of the film varied to a large extent depending on the time elapsed after the hydrolysis until the dipping of the coating solution. On a glass substrate, the films prepared by early dipping had inhomogeneous submicrometer-sized pores on the surface of the film. At increased reaction times, relatively narrow sized isolated macropores were observed and their size gradually decreased with the increase of reaction time. On a polyester substrate, in contrast, micrometer-sized isolated spherical gel domains were homogeneously deposited by earlier dippings. With an increase of reaction time, the volume fraction of the gel phase increased, then the morphology of the coating transformed into co-continuous gel domains and macropores, and finally inverted into the continuous gel domains with isolated macropores. The overall morphological variation with the reaction time was explained in terms of the phase separation and the structure freezing by the forced gelation, both of which were induced by the evaporation of methanol during the dipping operation.

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