scholarly journals Aging, visual information, and adaptation to task asymmetry in bimanual force coordination

2011 ◽  
Vol 111 (6) ◽  
pp. 1671-1680 ◽  
Author(s):  
Xiaogang Hu ◽  
Karl M. Newell

This study investigated the coordination and control strategies that the elderly adopt during a redundant finger force coordination task and how the amount of visual information regulates the coordination patterns. Three age groups (20–24, 65–69, and 75–79 yr) performed a bimanual asymmetric force task. Task asymmetry was manipulated via imposing different coefficients on the finger forces such that the weighted sum of the two index finger forces equaled the total force. The amount of visual information was manipulated by changing the visual information gain of the total force output. Two hypotheses were tested: the reduced adaptability hypothesis predicts that the elderly show less degree of force asymmetry between hands compared with young adults in the asymmetric coefficient conditions, whereas the compensatory hypothesis predicts that the elderly exhibit more asymmetric force coordination patterns with asymmetric coefficients. Under the compensatory hypothesis, two contrasting directions of force sharing strategies (i.e., more efficient coordination strategy and minimum variance strategy) are expected. A deteriorated task performance (high performance error and force variability) was found in the two elderly groups, but enhanced visual information improved the task performance in all age groups. With low visual information gain, the elderly showed reduced adaptability (i.e., less asymmetric forces between hands) to the unequal weighting coefficients, which supported the reduced adaptability hypothesis; however, the elderly revealed the same degree of adaptation as the young group under high visual gain. The findings are consistent with the notion that the age-related reorganization of force coordination and control patterns is mediated by visual information and, more generally, the interactive influence of multiple categories of constraints.

1999 ◽  
Vol 9 (3) ◽  
pp. 197-205
Author(s):  
L.L. Borger ◽  
S.L. Whitney ◽  
M.S. Redfern ◽  
J.M. Furman

Postural sway during stance has been found to be sensitive to moving visual scenes in young adults, children, and those with vestibular disease. The effect of visual environments on balance in elderly individuals is relatively unknown. The purpose of this study was to compare postural sway responses of healthy elderly to those of young subjects when both groups were exposed to a moving visual scene. Peak to peak, root mean squared, and mean velocity of the center of pressure were analyzed under conditions combining four moving scene amplitudes ( 2 . 5 ∘ , 5 ∘ , 7 . 5 ∘ , 10 ∘ ) and two frequencies of scene movement (0.1 Hz, 0.25 Hz). Each visual condition was tested with a fixed floor and sway referenced platform. Results showed that elderly subjects swayed more than younger subjects when experiencing a moving visual scene under all conditions. The elderly were affected more than the young by sway referencing the platform. The differences between the two age groups were greater at increased amplitudes of scene movement. These results suggest that elderly are more influenced by dynamic visual information for balance than the young, particularly when cues from the ankles are altered.


2010 ◽  
Vol 4 (3) ◽  
pp. 207-213
Author(s):  
Eliane Ferreira Carvalho Banhato ◽  
Isabel Cristina Gonçalves Leite ◽  
Danielle Viveiros Guedes ◽  
Alfredo Chaoubah

Abstract Although a normative process, changes in cognitive functioning vary among older adults. The differential diagnosis between normal and pathological aging must be made early using psychometrically adequate measures. Objectives: To assess the evidence of criterion validity of a Short Form (SF) of the Wechsler-III Scale containing eight subtests (SF8) by determining its sensitivity, specificity, positive and negative predictive values and cut-off points for Brazilian elderly from different age groups. Methods: 168 individuals, aged 60 years or above, living in the community or in an institution, were assigned to case and control groups, and investigated according to age range. Measures included a sociodemographic questionnaire, the Mini-Mental State Examination (MMSE), Verbal Fluency Test, Clock-Drawing Test and the SF8. Results: More than two thirds of the sample was women (73.8%), mean age was 74.5 years (SD=8.9), mean education was 6.2 years (SD=4.8) and 40.5% were widows/widowers. In the total sample, the best cut-off point for the SF8 was 142 while cut offs among individuals aged 60 to 69 years, 70 to 79 years, and more than 80 years were 160, 129 and 129, respectively. Conclusions: The results demonstrated the importance of different cut-off points for different age ranges. Sensitivity and specificity values of the SF8 were sufficiently high to warrant the use of the SF8 as an instrument to identify cognitive impairment in the elderly.


2015 ◽  
Vol 608 ◽  
pp. 23-27 ◽  
Author(s):  
Amitoj Bhullar ◽  
Nyeonju Kang ◽  
Jerelyne Idica ◽  
Evangelos A. Christou ◽  
James H. Cauraugh

Author(s):  
Geert Savelsbergh ◽  
John van der Kamp ◽  
Margot van Wermeskerken

The development of reaching actions in infancy is addressed by examining how visual perception is interwoven with movement coordination and control. Framed within the ideas of ecological psychology and the constraint-led approach, it is demonstrated that the development of reaching actions involves multiple interacting constraints such as maturation of the central nervous system, biomechanical factors, and informational constraints. None of these constraints uniquely prescribes the developmental trajectory, nor has one of them logical priority. In accordance with the central tenet of the ecological approach, we emphasize the role of visual information in the development of action. These findings are integrated within recent neuropsychological evidence for the existence of functionally and neuroanatomically separate visual systems.


Crisis ◽  
2016 ◽  
Vol 37 (2) ◽  
pp. 148-154 ◽  
Author(s):  
Karoly Bozsonyi ◽  
Peter Osvath ◽  
Sandor Fekete ◽  
Lajos Bálint

Abstract. Background: Several studies found a significant relationship between important sport events and suicidal behavior. Aims: We set out to investigate whether there is a significant relationship between the raw suicide rate and the most important international sports events (Olympic Games, FIFA World Cup, UEFA European Championship) in such an achievement-oriented society as the Hungarian one, where these sport events receive great attention. Method: We examined suicide cases occurring over 15,706 days between January 1, 1970, and December 31, 2012 (43 years), separately for each gender. Because of the age-specific characteristics of suicide, the effects of these sport events were analyzed for the middle-aged (30–59 years old) and the elderly (over 60 years old) generations as well as for gender-specific population groups. The role of international sport events was examined with the help of time-series intervention analysis after cyclical and seasonal components were removed. Intervention analysis was based on the ARIMA model. Results: Our results showed that only the Olympic Games had a significant effect in the middle-aged population. Neither in the older male nor in any of the female age groups was a relationship between suicide and Olympic Games detected. Conclusion: The Olympic Games seem to decrease the rate of suicide among middle-aged men, slightly but significantly.


2019 ◽  
pp. 5-34
Author(s):  
Anna L. Lukyanova ◽  
Rostislav I. Kapeliushnikov

The paper analyzes changes in job opportunities of older workers in Russia in the period 2005—2017. The study uses the data from the Russian Labor Force Survey conducted by Rosstat. Changes in the occupational and industrial composition of elderly workers follow the trends pursued by other age groups: employment shifts from low- to high-skilled occupations, from physical to intellectual labor, and from material production to the service sector. We find a stronger polarization among older workers as their occupational structure is biased in favor of, on the one hand, the most and, on the other hand, the least qualified types of jobs. Employment of the elderly has fallen sharply in agriculture and manufacturing with a significant increase in trade, education, and health. Although the employment structure of older workers is generally more “traditionalist”, recent decades have witnessed its transformation in “progressive” directions, similarly to other age groups. These findings suggest that the legislated increase in the state retirement age is not likely to give rise to sizeable unemployment among the elderly. Most of them will be able to work in the occupations and industries previously dominated by young and prime-age workers.


2020 ◽  
Author(s):  
Jagjit S Soar

he current COVID-19 pandemic now believed to be based on the mutation of the SARS-CoV virus (first reported in 2002) to SARS-CoV-2 emerging in 2019, is naturally causing extreme worry and concern around the world with sometimes mixed and incoherent messages on how to deal with it. There is a plethora of information from previous epidemics caused by other coronaviruses such as severe acute respiratory syndrome, SARS (2002) and Middle East respiratory syndrome MERS (2012) from which we can extrapolate guidance on how to deal with the current pandemic. In the current absence of specific pharmaceutical agents, we propose assessing the extended tools that we already possess in our biological armoury to combat, prevent and control the spread of this virus. Using a set of precise criteria to locate such possible contenders, we conducted literature searches to find compounds that met these criteria. We have now reduced this to a shortlist of three agents that may be the best candidates. We propose vitamin C, vitamin D and Curcumin fit our criteria well. These compounds are widely available to the general public. They are available online and over-the-counter as supplements. Otherwise healthy individuals are safely able to self-administer these agents as a prophylactic to protect themselves and to enhance their immune response. This would be especially desirable for the elderly and at risk groups. These agents can also be used as adjunct therapy, particularly for those who may have early symptoms. This preventative therapy could be implemented whilst awaiting specific pharmaceutical drugs to emerge as a treatment for COVID-19. Our suggested compounds are a highly cost-effective way to potentially reduce the mortality that is regretfully mounting as a result of COVID-19 infection. The biological mode of action and the dosing of these compounds are summarised.


2019 ◽  
Vol 72 (8) ◽  
pp. 1466-1472
Author(s):  
Grażyna Kobus ◽  
Jolanta Małyszko ◽  
Hanna Bachórzewska-Gajewska

Introduction: In the elderly, impairment of kidney function occurs. Renal diseases overlap with anatomic and functional changes related to age-related involutionary processes. Mortality among patients with acute renal injury is approximately 50%, despite advances in treatment and diagnosis of AKI. The aim: To assess the incidence of acute kidney injury in elderly patients and to analyze the causes of acute renal failure depending on age. Materials and methods: A retrospective analysis included medical documentation of patients hospitalized in the Nephrology Clinic during the 6-month period. During this period 452 patients were hospitalized in the clinic. A group of 77 patients with acute renal failure as a reason for hospitalization was included in the study. Results: The prerenal form was the most common cause of AKI in both age groups. In both age groups, the most common cause was dehydration; in the group of patients up to 65 years of age, dehydration was 29.17%; in the group of people over 65 years - 43.39%. Renal replacement therapy in patients with AKI was used in 14.29% of patients. In the group of patients up to 65 years of age hemodialysis was 16.67% and above 65 years of age. -13.21% of patients. The average creatinine level in the group of younger patients at admission was 5.16 ± 3.71 mg / dl, in the group of older patients 3.14 ± 1.63 mg / dl. The size of glomerular filtration GFR in the group of younger patients at admission was 21.14 ± 19.54 ml / min, in the group of older patients 23.34 ± 13.33 ml / min. Conclusions: The main cause of acute kidney injury regardless of the age group was dehydration. Due to the high percentage of AKI in the elderly, this group requires more preventive action, not only in the hospital but also at home.


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