scholarly journals Effects of age and task difficulty on postural sway, variability and complexity

2020 ◽  
pp. 105971232096397
Author(s):  
Mohsen Shafizadeh ◽  
Shahab Parvinpour ◽  
Marzie Balali ◽  
Mohsen Shabani
Keyword(s):  
Older Adults ◽  
Task Difficulty ◽  
Postural Sway ◽  
Linear Trend ◽  
Force Plate ◽  
Control Mechanisms ◽  
Dependent Variables ◽  
The Stability ◽  
Physical Challenges ◽  
Different Levels

This study aimed to examine the effects of age and the task difficulty on postural sway, variability and complexity. The participants were 90 able-bodied individuals including children ( n = 39; age: 5.89 ± 0.94 years), young adults ( n = 30; age: 23.23 ± 1.61 years) and older adults ( n = 21; age: 64.59 ± 5.24 years) who took part in different balance tasks that had different levels of cognitive and physical challenges. The main dependent variables were postural sway area, postural variability and postural complexity. The participants stood on a standard force plate for 10 s in each task condition, and the centre of pressure displacement was collected at 100-Hz sampling frequency. The results of this study showed that children and older adults, in the more difficult tasks, had greater sway area and complexity and less postural variability. In addition, there was a linear trend in the stability measures as the difficulty of the task was increased. In conclusion, special populations, such as children and older adults, were more sensitive to the balance changes and used active control mechanisms to minimise the risk of losing balance in more challenging conditions.

The Relationship Between Trunk Muscle Thickness and Static Postural Balance in Older Adults

2020 ◽  
Vol 28 (2) ◽  
pp. 269-275
Author(s):  
Ece Acar ◽  
Tamer Çankaya ◽  
Serkan Öner
Keyword(s):  
Older Adults ◽  
Postural Balance ◽  
Postural Sway ◽  
Force Plate ◽  
Muscle Thickness ◽  
Trunk Muscle ◽  
Rectus Abdominis ◽  
Trunk Muscles ◽  
The Relationship ◽  
Stability Area

Trunk muscles are required for safety of movement in aging. The authors aimed to investigate the relationship between trunk muscle thickness and the static postural balance in older adults. A total of 31 females and 23 males with a mean age of 73.39 ± 6.09 completed the study. The thickness of the trunk muscles was determined with ultrasound imaging. Postural balance was assessed with force plate. There was a positive weak correlation between right and left upper rectus abdominis muscle thickness and anterior stability area (p < .05, r > .3). The negative and moderate correlation was determined between the left lower rectus abdominis and the perturbated stability sway value (p < .01, r > .5). The increase in trunk muscle thickness in older adults increases the postural stability area and decreases the postural sway especially in the mediolateral direction.

scholarly journals Stability of the Mitigating Effect of Students’ Perceived Teacher Enthusiasm on Class-related Boredom: Moderating Role of Boredom Proneness and Perceived Task Difficulty

2020 ◽  
Vol 17 (8) ◽  
pp. 2645 ◽  
Author(s):  
Chen Wang ◽  
Yunjun Hu ◽  
Xia Zhang ◽  
Jing Wang ◽  
Guangli Cui ◽  
...  
Keyword(s):  
Task Difficulty ◽  
Learning And Teaching ◽  
Teacher Enthusiasm ◽  
Boredom Proneness ◽  
The Stability ◽  
The Relationship ◽  
Moderating Role ◽  
Different Levels

The aim of the current study was to explore the stability of the mitigating effect of students’ perceived teacher enthusiasm on class-related boredom and the moderating role of boredom proneness and perceived task difficulty in such effect. A total of 984 students from five universities in China participated in the study. Questionnaires on class-related boredom, perceived teacher enthusiasm, boredom proneness, and perceived task difficulty were used to measure the respective variables. Results showed that boredom proneness and perceived task difficulty significantly moderated the relationship between perceived teacher enthusiasm and class-related boredom. Moreover, when considering perceived task difficulty, boredom proneness became silent in the moderating path between perceived teacher enthusiasm and class-related boredom. Even so, the mitigating effect of students’ perceived teacher enthusiasm on class-related boredom was stable in students with different levels of boredom proneness and perceived task difficulty. The implications for learning and teaching are discussed.

Does the Effect of Stereotypes in Older People Depend Upon Task Intensity?

2021 ◽  
pp. 016402752110206
Author(s):  
Maxime Deshayes ◽  
Raphaël Zory ◽  
Rémi Radel ◽  
Corentin Clément-Guillotin
Keyword(s):  
Older Adults ◽  
Stereotype Threat ◽  
Older Women ◽  
Task Difficulty ◽  
Negative Stereotypes ◽  
Perceived Effort ◽  
Stereotype Threat Theory ◽  
Threat Theory ◽  
Different Levels ◽  
Muscular Effort

This study examined the effect of negative and positive stereotypes on the strength produced by older adults at different perceived effort intensities, reflecting different levels of task difficulty. Fifty older women were randomly assigned to a positive stereotype, a negative stereotype, or a control condition. Before (T1) and after (T2) the stereotype manipulation, they were asked to perform a voluntary isometric contraction at a level of muscular effort that corresponded to four perceived effort intensities (“easy,” “moderate,” hard” and “very hard”). Results showed that participants attained greater strength during the easy and hard tasks after exposure to both positive and negative stereotypes. At the moderate and very hard intensities, stereotype induction did not significantly change the strength from the baseline performance. While these results are not fully in line with the stereotype threat theory, they provide evidence that task difficulty could modulate the effect of aging stereotypes during physical tasks.

scholarly journals Using Augmented Reality with Older Adults in the Community to Select Design Features for an Age-Friendly Park: A Pilot Study

2020 ◽  
Vol 2020 ◽  
pp. 1-8
Author(s):  
Edgar R. Vieira ◽  
Fernanda Civitella ◽  
Jorge Carreno ◽  
Miburge G. Junior ◽  
Cesar F. Amorim ◽  
...  
Keyword(s):  
Older Adults ◽  
Pilot Study ◽  
Augmented Reality ◽  
Postural Sway ◽  
Small Sample Size ◽  
Force Plate ◽  
Small Sample ◽  
Public Parks ◽  
Large Variability ◽  
Active Lifestyles

Sedentary behavior is prevalent in older adults. Older adults often underutilize public parks for exercising because the parks do not support their needs and preferences. Engaging older adults on the redesign of parks may help promote active lifestyles. The objectives of this pilot study were to evaluate (1) the effects of wearing augmented reality (AR) and virtual reality (VR) glasses on balance; (2) the effects of different virtual walls separating the walking trail from the roadway on older adults’ gait, and (3) the preferences of the participants regarding wall design and other features. The participants were ten older adults (68 ± 5 years) who lived within two miles from the park. Balance and gait were assessed using a force plate and an instrumented mat. It was feasible to use AR with older adults in the park to evaluate features for redesign. Motion sickness was not an issue when using AR glasses, but balance was affected when wearing VR goggles. The area of postural sway increased approximately 25% when wearing AR glasses, and it increased by close to 70% when wearing VR goggles compared to no glasses. This difference is clinically relevant; however, we did not have enough power to identify the differences as statistically significant because of the small sample size and large variability. Different walls did not significantly affect the participants’ gait either because they did not alter the way they walked or because the holograms were insufficiently realistic to cause changes. The participants preferred a transparent wall rather than tall or short solid walls to separate the park from the roadway.

Functional Control of Stance in Older Adults

2016 ◽  
Vol 5 (1) ◽  
pp. 23-29 ◽  
Author(s):  
Thomas A. Stoffregen
Keyword(s):  
Older Adults ◽  
Healthy Aging ◽  
Postural Sway ◽  
Field Studies ◽  
Laboratory Research ◽  
Body Sway ◽  
Healthy Older Adults ◽  
Functional Control ◽  
The Stability ◽  
Definition Of

It is widely assumed that healthy aging includes a decline in the stability of standing body sway. Certainly, the spatial magnitude of postural sway increases with age. However, the interpretation of this effect as a decline in the ability to stabilize posture rests, in part, on assumptions about the nature and definition of stability in stance. In this article, I review data on the control of standing posture in healthy older adults. I focus on a growing list of studies that demonstrate the retention, among healthy older adults, of the ability functionally to modulate postural sway in support of “suprapostural” activities. I address laboratory research, but also field studies carried out in a setting that dramatically challenges the control of stance: life on ships at sea. I argue that it may be possible, and certainly will be useful, to address directly the functional control of stance in older adults.

CHANGES IN INSTABILITY AND IRREGULARITY OF THE ELDERLY DUE TO DIFFERENT BALANCE ABILITY

2017 ◽  
Vol 17 (07) ◽  
pp. 1740034
Author(s):  
DONG WON KANG ◽  
JEONG WOO SEO ◽  
TAE HO KIM ◽  
HAE MI CHO ◽  
JIN SEUNG CHOI ◽  
...  
Keyword(s):  
Older Adults ◽  
Postural Control ◽  
Neurological Disease ◽  
Postural Sway ◽  
Inertial Sensor ◽  
Control Mechanisms ◽  
Multi Scale ◽  
Eyes Closed ◽  
Balance Ability ◽  
The Impact

Older adults with a balance-related neurological disease or who have experienced previous falling incidents tend to show increase in instability and changes in irregularity of postural control. This study analyzed the impact of differences in balance ability on the instability and irregularity of postural control in older adults without neurological disease and previous fall experiences. The 49 subjects were older adults aged 65 years and above who did not have neurological disease and prior falling incidents during the previous year. The subjects were classified into two groups of 27 healthy (Berg score [Formula: see text]) and 22 balance-impaired older adults (Berg score [Formula: see text]) according to the Berg balance scale. Each subject was asked to hold in the standing position with eyes closed and with eyes open for one minute. Postural sway was measured along with acceleration using an inertial sensor attached to the subject’s waist. The measured postural sway was calculated using linear measures (95% confidence ellipse area, root mean square) that represented instability and nonlinear measures (sample, multi-scale and composite multi-scale entropy) that represented irregularity. All linear measures showed an increase in the average value in the balance-impaired older adult group’ as well as significant differences between the two groups, whereas the nonlinear measures did not show any differences. These findings indicated that differences in instability were not necessarily accompanied by irregularity changes, and the similarities in irregularity were assumed to be the result of the postural control mechanisms of the subjects without neurological diseases and prior fall incidents being similar to those of subjects with physical injuries.

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.

Changes in Postural Sway and Its Fractions in Conditions of Postural Instability

2006 ◽  
Vol 22 (1) ◽  
pp. 51-60 ◽  
Author(s):  
Luis Mochizuki ◽  
Marcos Duarte ◽  
Alberto Carlos Amadio ◽  
Vladimir M. Zatsiorsky ◽  
Mark L. Latash
Keyword(s):  
Average Velocity ◽  
Postural Sway ◽  
Center Of Pressure ◽  
Force Plate ◽  
Control Mechanisms ◽  
Mean Square ◽  
Loss Of Balance ◽  
Eyes Open ◽  
Support Area ◽  
Anterior Posterior

We investigated changes in postural sway and its fractions associated with manipulations of the dimensions of the support area. Nine healthy adults stood as quietly as possible, with their eyes open, on a force plate as well as on 5 boards with reduced support area. The center of pressure (COP) trajectory was computed and decomposed into rambling (Rm) and trembling (Tr) trajectories. Sway components were quantified using RMS (root mean square) value, average velocity, and sway area. During standing on the force plate, the RMS was larger for the anterior-posterior (AP) sway components than for the mediolateral (ML) components. During standing on boards with reduced support area, sway increased in both directions. The increase was more pronounced when standing on boards with a smaller support area. Changes in the larger dimension of the support area also affected sway, but not as much as changes in the smaller dimension. ML instability had larger effects on indices of sway compared to AP instability. The average velocity of Rm was larger while the average velocity of Tr was smaller in the AP direction vs. the ML direction. The findings can be interpreted within the hypothesis of an active search function of postural sway. During standing on boards with reduced support area, increased sway may by itself lead to loss of balance. The findings also corroborate the hypothesis of Duarte and Zatsiorsky that Rm and Tr reveal different postural control mechanisms.

Implications of Person Fluctuation for the Stability and Validity of Test Scores

Methodology ◽  
2006 ◽  
Vol 2 (4) ◽  
pp. 142-148 ◽  
Author(s):  
Pere J. Ferrando
Keyword(s):  
Item Response ◽  
Test Scores ◽  
Temporal Stability ◽  
Person Fit ◽  
Item Parameters ◽  
Individual Trait ◽  
The Stability ◽  
The Individual ◽  
Different Levels ◽  
Fluctuation Model

In the IRT person-fluctuation model, the individual trait levels fluctuate within a single test administration whereas the items have fixed locations. This article studies the relations between the person and item parameters of this model and two central properties of item and test scores: temporal stability and external validity. For temporal stability, formulas are derived for predicting and interpreting item response changes in a test-retest situation on the basis of the individual fluctuations. As for validity, formulas are derived for obtaining disattenuated estimates and for predicting changes in validity in groups with different levels of fluctuation. These latter formulas are related to previous research in the person-fit domain. The results obtained and the relations discussed are illustrated with an empirical example.

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