Proposal for a new body sway evaluation method

This study is aimed at examining body sway factors for 1107 healthy people aged 16 to 69 years and to propose a practical body sway evaluation method. The center of foot pressure measurement was carried out twice for 1 min. with a 1-min. rest. 30 parameters with high reliability selected from 6 domains (distance, distribution of amplitude, area, velocity, power spectrum, and body sway vector) were summarized objectively into 4 body sway factors (unit time sway, front-back sway, left-right sway, and high frequency band power). Factor scores were calculated by the estimate equation and the total standard scores of parameters with high factor loadings. Considering this result, a total standard score for each factor was classified into 4 percentile categories based on percentile rank. Using this classification criteria, body sway scores for each individual were classified into any of the above 4 domains for each factor. It was confirmed that young adults mainly belong to percentile Categories A and B and the elderly mainly belong to percentile Categories C and D. It was found that a great effect on body sway occurred when an individual's conscious condition changed (contracting a cold or after exercise). In conclusion, the body sway of healthy people can be explained by these 4 sway factors. An evaluation of the body sway pattern using the 4 sway factors may enable us to concretely understand individuals' disorders and abnormal states in addition to changes in body sway that occur with aging.     

Selection of useful parameters to evaluate center-of-foot pressure movement

This study aimed to objectively summarize the parameters for evaluating the center-of-foot pressure and to select useful parameters with high reliability and validity with 220 healthy university students. In addition, 50 healthy university students were selected to examine cross validity. The measurement of center-of-foot pressure was carried out 3 times with a 1-min. rest and the mean of Trials 2 and 3 was used for the analysis. The data sampling frequency was 20 Hz. 34 parameters were selected from 6 domains: distance, distribution, area, velocity, spectrum, and vector. As a result of factor analysis the following four factors were interpreted: unit time sway, front-back sway, left-right sway and high frequency band sway. Their intraclass correlation coefficients were very high (ICC=.89-.95). Five parameters representing each factor were selected using stepwise selection by regression analysis. There were no significant differences between the mean factor scores estimated by the above five parameters in the original and in cross-validity groups, and relationships between factors in both groups were very high. The center-of-foot pressure may be predicted and systematically evaluated by the above four factors. Five parameters selected from each factor are considered to be useful ones with high validity and practicability.     

A psychophysiological study on the function of the response‐stop in the Eriksen task1,2

Abstract: In the Eriksen task, we examined the hypothesis ( Iwaki, 1998 ) that a negative event‐related potential, which was enlarged at the frontal site synchronized with the presentation of an erroneous response causing stimulus, is related to the response‐stop function. Fourteen subjects responded selectively with their hands to the stimuli that consisted of a central target letter and surrounding compatible noise letters (e.g., HHHHH) or incompatible noise (e.g., SHHHS for small‐conflict condition or SSHSS for large‐conflict). The results showed that the increased negativity for the incompatible stimuli was synchronized with the stimulus onset but not with the response. Based on the hypothesis above, it is predicted that greater enhancement of an erroneous response by a stimulus causes the response‐stop to work harder in order to avoid an error, and this results in the larger negativity. This was supported by the evidence showing that the negativity was largest for the large‐conflict incompatible stimulus, followed by the small‐conflict, and then the compatible. We also discuss the possibility that the negativity is the NO‐GO potential concerned with the response‐stop function.     

Cross-cultural comparison of motivation to learn in physical education: Japanese vs Swedish schoolchildren

The present study compared differences between Japanese and Swedish schoolchildren in learning motivation-related variables in physical education. The subjects were 1,562 Japanese fifth and sixth graders (776 boys and 786 girls) ranging in age from 10 to 12 years and 573 Swedish fifth graders (306 boys and 267 girls) from 10 to 13 years (M = 11.4, SD = 0.5). They completed three questionnaires to evaluate the children's learning motivation, factors supporting motivation to learn, and preferences of learning behavior. The questionnaires were taken from Nishida's Diagnosis of Learning Motivation in Physical Education Test, a multidimensional and comprehensive test that measures learning motivation. A 2 x 2 (country by sex) multivariate analysis of variance indicated both Swedish boys and girls scored significantly higher than the Japanese children on most subscales. Results were discussed in relation to differences in the sports environment and culture of the two countries.     

Experimental evaluation of rehabilitation in chronic obstructive pulmonary disease: short-term effects on exercise endurance and health status

Randomly assigned 119 adults with chronic obstructive pulmonary disease to an 8-week comprehensive rehabilitation program or to an 8-week education control program. Comprehensive pulmonary rehabilitation included education, physical and respiratory therapy instruction, psychosocial support, and supervised exercise training; education control included biweekly classroom instruction and discussions on respiratory therapy, medical aspects of lung disease, clinical pharmacology, and diet, but no exercise training. Both groups received extensive physiological and psychosocial evaluation before and after the intervention. Six months after enrollment, patients randomly assigned to the rehabilitation program showed significant increases in exercise endurance, whereas patients randomly assigned to control program showed nonsignificant increases. Improvement in self-efficacy was correlated with improvements in exercise endurance.     

Comparison of power spectrum characteristics of body sway during a static upright standing posture in healthy elderly people and young adults

This study was designed to compare peak frequency, mean power frequency, and power spectrum of each frequency band of body-sway time series and velocity time series power spectra between 30 healthy elderly people and 30 young adults and to clarify their frequency characteristics. Peak frequency and mean power frequency differed between groups, being higher for elderly persons, and the difference was marked in the front-back direction. When comparing power spectra of three domains (A: 0.02-0.2 Hz, B: 0.2-2.0 Hz, and C: 2.0-10.0 Hz) of an international standard, a significant age-group difference was found only in the front-back direction. Young adults were higher in the low frequency band (A domain) in sway time series, and the elderly group was higher in the high frequency band (C domain) in body-sway velocity time series. However, almost all power spectra of both groups appeared in the low frequency band. The present results suggested frequency characteristics of healthy people occur in the low frequency band, but the elderly group compared with the young adults had more characteristics in the high frequency band. Their frequency characteristics cannot be properly evaluated by the international standard established to screen disorders. It may be necessary for healthy people to have new evaluation frequency sections when considering power spectrum characteristics of sway time series and sway-velocity time series.     

Independent age cues for infancy and older age in one face: evidence for rivalry in age perception

Participants estimated the ages of infants, teens, and adults in their 20s and 60s, using averaged facial images, as well as digitally transformed images of two different age groups. Since a blended face has intermediate features of the component faces, age of the combined faces was hypothesized to be perceived as the mean age of the component faces. However, the perceived age was underestimated when the transformed face included an infant, but overestimated when the face included a person in their 60s. From this one may infer the faces of infants and adults in their 60s have strong age cues. The estimated ages for blended images of infants and adults in their 60s showed a clear bipolar distribution, with one peak at 5-9 years and the other at 50-54 years. Analysis of individual variation showed that the different response to infants-60s faces was related to variations in sensitivity to 60s faces, not to a general perceptual tendency or confused responses to ambiguous appearing faces. Thus, cues for infancy and older age are qualitatively independent and can co-exist in one face, yielding a rivalry in age perception.     

Comparison of the body-sway characteristics of young adults compared to healthy elderly and elderly with equilibrium disorder

The study compared body-sway characteristics of 380 young adults, 342 generally healthy elderly without disequilibrium disorders, and a group of 33 elderly with disequilibrium disorders. Center of foot pressure (COP) was measured for 1 min. using an Anima's stabilometer G5500 with a data sampling frequency of 20 Hz. Four high reliability measures were used to evaluate body sway (unit time sway, front-back sway, and a left-right sway, and high frequency band power). Unit time sway, left-right sway, and high frequency band power were significantly larger for the group of elderly with disequilibrium disorders, and smaller for the healthy elderly people and young adults, in that order. Front-back sway was significantly larger in the elderly with disequilibrium disorders and healthy elderly than in young adults. The elderly with disequilibrium disorders had a larger and faster sway than young adults as well as the healthy elderly, particularly in the left-right direction. It appears aging was specifically associated with larger influence on the front-back sway.     

Power spectrum characteristics of sway position and velocity of the center of pressure during static upright posture for healthy people

This study assessed sex and individual differences in sway-position and velocity power spectra and reliability of power frequency with 30 health young people. The body sway for 1 min. was measured twice over a 1-min. rest. There were no significant sex differences in the spectra. Frequency bands with a large coefficient of variance over 10.0 appeared up to 0.6 Hz. 75% relative accumulated power frequency appeared at 1.10-1.23 Hz in the position and at 2.00-3.05 Hz in the velocity spectra. Most power was in the low frequency band (A and B frequency intervals) of the international standard. Relative accumulated power frequency of position and velocity power spectra was reasonably reliable. It may be necessary to establish a new evaluation frequency interval by direction of sway-position and velocity using relative accumulated power frequency for healthy people.     

A TEST OF McCLELLAND'S THEORY OF ACHIEVEMENT MOTIVATION IN BRITAIN,JAPAN, IRELAND AND ISRAEL

Les auteurs tirent deux hypothèses de la théorie de McClelland, selon laquelle les taux rapides de développement économique sont sous-tendus par un fort besoin de réussite. La première hypothèse pose que les étudiants des pays à forte croissance économique manifesteront une préférence pour les affaires, et la seconde qu'ils se sentiront plus concernés par la réussite professionnelle. Les recherches ont lieu au Japon et en Israel, pays à forte croissance économique, en Grande-Bretagne et en Irlande, pays à faible croissance économique, sur des échantillons d'étudiants mâles d'université. Les résultats ne confirment pas la première hypothèse, mais confirment la seconde.