Some researchers have reported that moderate physical exercise improves cognitive function, and that exercise at high intensity beyond the optimal point attenuates performance, in an inverted U-relationship. The optimal intensity of physical exercise for cognitive function might be related closely to the anaerobic threshold. It has been regarded as an extremely useful index for effective training intensity in cardiorespiratory fitness. This review specifically addresses acute physical exercise around the anaerobic threshold in healthy subjects and its effects on task performance during or after exercise. We discuss physiological factors for the facilitating effect of moderate exercise on cognitive function, which indicates the initial basis in complicated mechanisms of the benefits of physical exercise on cognitive performance.

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It is generally thought that fatigue is modulated during prolonged exhaustive motor tasks by the bilateral motor cortex. It remains unclear, however, how fatigue is modulated during motor tasks and how information about fatigue affects motor cortex activities in healthy humans. These results may help explain why fatigue is so prevalent in patients with neurological disorders. The purpose of the present study was to investigate the time course of oxygenation of the ipsilateral motor cortex during an exhaustive pinching task. Seven healthy right-handed subjects participated in the study. Near-infrared spectroscopy over the bilateral motor cortices was used to measure activity throughout the pinching task. Subjects performed a sustained maximal voluntary contraction of 50–60% with their left hands until voluntary exhaustion was reached. After the start of the motor task, oxygenation to the contralateral motor cortex increased significantly compared with the resting value (p<0.05). However, with the passage of time, it decreased significantly compared with the resting value (p<0.05). In addition, oxygenation of the ipsilateral motor cortex significantly increased after the start of the motor task, and then decreased significantly at voluntary exhaustion compared with the resting value (p<0.05). These results suggest an interaction between the bilateral motor cortices during motor tasks.

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Anthropometrical findings about proportions of the human body have a long tradition; most of them, however, are rather theoretical. To improve this situation a pragmatic and applicable definition of proportions, normal as well as deviating, is needed. The purpose of this paper is to set up three proportion types for body length measures: leggy–normal–stocky, and their rate in the population of adults in an industrial society (Germany). Based on queries of an actual anthropometrical database metrical limits for these three types are suggested regarding their influence on the most important body length measures in standing and sitting positions. The number of cases with normal proportions is about 60%, leggy and stocky types both reaching up to 20%. The metrical limits are proposed in order to account for differences between those proportion types which are relevant for ergonomics. When solving complex multidimensional design tasks (e.g. workplaces, vehicle interior design, personal equipment) users of anthropometrical data who do not have the opportunity to work with multivariate databases need supplementary information about the proportions of the human body. For this reason such supplementary information concerning proportions is being given here by physiological anthropologists. The application of the findings presented is exemplified in scenarios of ergonomic relevance.

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The effects of reward and punishment are different, and there are individual differences in sensitivity to reward and punishment. The purpose of this study was to investigate the effects of reward and punishment on task performance, mood, and autonomic nervous function, along with the interaction with personality. Twenty-one healthy female subjects volunteered for the experiment. The task performance was evaluated by required time and total errors while performing a Wisconsin Card Sorting Test. We assessed their personalities using the Minnesota Multiphasic Personality Inventory (MMPI) questionnaire, and mood states by a profile of mood states. Autonomic nervous function was estimated by a spectral analysis of heart rate variability, baroreflex sensitivity, and blood pressure. Repeated measures analysis of variance (ANOVA) revealed significant interaction of condition×time course on mood and autonomic nervous activity, which would indicate a less stressed state under the rewarding condition, but revealed no significant interaction of condition×time course on the task performance. The interactions with personality were further analyzed by repeated measures ANOVA applying the clinical scales of MMPI as independent variables, and significant interactions of condition×time course×Pt (psychasthenia) on task performance, mood, and blood pressure, were revealed. That is, the high Pt group, whose members tend to be sensitive and prone to worry, showed gradual improvement of task performance under the punishing situation with slight increase in systolic blood pressure, while showed no improvement under the rewarding situation with fatigue sense attenuation. In contrast, the low Pt group, whose members tend to be adaptive and self-confident, showed gradual improvement under the rewarding situation. Therefore, we should carefully choose the strategy of reward or punishment, considering the interaction with personality as well as the context in which it is given.

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This paper investigates the recognition process of Japanese kanji and sentences for Chinese bilinguals and Native Japanese speakers (NJS), by analyzing the event-related potential (ERP) differences between the two groups while they visually recognized Japanese kanji and sentences. The results showed that no significant differences were found between the two groups while they recognized Japanese kanji, but significant differences were found in the Japanese sentences condition. The results demonstrated that the neural mechanisms of recognition processes of Japanese sentences including kana between the two groups were not identical. When recognizing ambiguous sentences, Chinese bilinguals' P600 only appeared over the right frontal lobe, reflecting that syntactic integration and revision of ambiguous sentences for Chinese bilinguals was related with the right hemisphere. The results showed, for Chinese bilinguals, the difficulty of Japanese language learning was the recognition and understanding of Japanese sentences with kana, not Japanese kanji. We would like to provide a scientific learning method for Chinese bilinguals to enhance their Japanese language learning efficiency from the aspect of brain science.

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This study examined age and sex differences of controlled force exertion in 207 males and 249 females aged 15 to 86 years. The subjects matched the submaximal grip strength of their dominant hand to changing demand values, appearing as a sinusoidal waveform on the display of a personal computer. The total difference (%) between the demand value and the grip exertion value for 25 sec was used as an evaluation parameter. Significant linear regressions were identified, but there was no significant difference in the rate of increase of both sexes. Analysis of variance showed insignificant differences among the means of both sexes, except for those of the 20–24yr-old group, and the differences between means of subjects greater than 50 years of age and 20 years of age increased in both sexes. Individual differences were almost the same in both sexes. The errors in controlled force exertion did not show a significant sex difference and tended to increase with age in both sexes. However, their rates of increase were significant only after 50 years of age.

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