Learning process of manual assembly task is ever becoming a serious problem under the situation where a small lot size, various types of products and short product life is prevailing. The simple manipulative task of “pick and place” has been performed with instructions available through a computer. The method of measuring the amount of memorized information throughout the learning process can be applied to analyze the operator's learning ability. The experimental formula which represents the memorization process can be used to evaluate the learning effect of a manual assembly task.

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Workload of three different types of laboratory tasks, each of which has three difficulty levels, was measured with the Japanese version of NASA Task Load Index (TLX), and the result demonstrated that the obtained workload scores were sensitive to the task difficulty in any of the tasks. The weights of the rating scales, which were decided through the pairwise comparison of the importance of the scales, were found to be unique to each task. This indicates that the three experimental tasks had different constitution of loading factors from each other, and that TLX is applicable to various types of workload. Then, correlation and regression analyses were carried out and the results were compared with those reported for the original NASA-TLX. Finally, workload socres which were obtained with no pairwise comparison from the ratings on the same TLX scales were compared with the regular Weighted Workload (WWL) scores, and their validity as alternative indices of workload was discussed.

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Many researchers agree that violent movies induce violence among viewers. However, further research in U. S. and Europe suggests that additional information, such as reaction of other audiences, will affect the viewer's attitude toward the viewing. In this study, we conducted a research for replication in Japan to examine if these results could be extrapolated across sociological and cultural backgrounds. The subjects consisted of 394 males and 399 females, either in fifth grade and in eighth grade. One of the following three comments was made upon viewing of a portion of a movie which portrayed violence; (1) educational, (2) entertainment, or (3) neutral. The results show that although there were no differences among groups concerning general likings or reality testing, there were significant differences in evaluating cruelty and about urges for imitation.

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In order to evaluate visual fatigue of VDT (Visual Display Terminals) operators, flick movement in involuntary eye movement during binocular fixation on the small target is measured before and after 2-hours VDT workload (visual search task) by a photo-electric recording of corneal reflection. An emphasis is put on analyses on variation of flick in which horizontal components of frequency, interval, amplitude and velocity are obtained. For 2-hours VDT work, the significant decrease in frequency, amplitude and velocity of flick and the significant increase of interval of flick are observed with the level of 1%. Near point distance (NP), subjective symptoms and performance are also measured during VDT work. NP and the subjective symptoms show the visual fatigue. The correlation between increase of NP and change of flick characteristics is recognized. It is concluded that the variation of components obtained in flick is the effective index to evaluate the visual fatigue which manifests not physical aspect but mental aspect for subject.

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The ability to detect errors in the intellectual work was studied in terms of the influences by the personality and the results in the aged group were compared with those of the younger's. In the experiment, two numbers were presented on the CRT display. Then the subjects judged whether it was an even or odd number from the sum of two numbers and input the answer by clipping the button of the mouse device. And the Maudsley Personality Inventory which measures three personality dimensions such as “Lie-scale score” was administered. Subjects were twenty-two aged men and twenty younger men.
The results of this study were as follows; (1) The younger group showed shorter reaction time but in rate of correct answers the aged group showed higher scores than those of the younger group. (2) The aged group had a tendency to show high score in Liescale score and Lie-scale score was in close correlation with rate of correcting errors. (3) Lie-scale score of the aged group also showed close correlation with rate of error points.

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