Function Of Concentration Maintenance Research Articles

Work load due to stamping task as a simple repetitive hand work (author's transl)

An experimental study was carried out on stamping task using no conveyers with short work cycle which was taken as featuring simple repetitive hand work. Each phase of this work was allowed to each subject. Seventeen healthy adults, 8 males and 9 females, were engaged in the 120 minutes, stamping task. They were tested by their function of concentration maintenance (TAF), by flicker frequency and 30 items of subjective symptoms as advocated by the Japan Association of Industrial Health. Quantities of work for each 10 minutes were calculated. The results obtained were as follows: 1) Number of stamped cards by male subjects was more than that by female subjects. 2) Pace of work performance in the female subjects was being kept more in balance with their capacity in comparison with the male subjects. 3) The results of TAF and FF tests showed that the body load in the male subjects were greater than in the female subjects.

Effect of Odor on The Human Body

A dynamic flow type of human olfactometer was developed.Twenty-six healthy male adults were used for testing detection threshold of ten kinds of standard test odorants diluted with nujol. They were β-phenylethyl alcohol, cycloten, iso-valeric acid, γ-undecalactone, skatol, exalotolide, phenol, dl-camphor, diallyl sulfide and acetic acid. Distribution of detection threshold of these odorants showed almost a normal curve. Exposures to β-phenylethyl alcohol and skatol showed a large coefficient of variation in detection threshold. On the contrary, acetic acid and cycloten showed a small deviation.Five healthy male adults were exposed to iso-valeric acid (10-5) using the olfactometer in the odor exposure chamber, and the function of concentration maintenance (TAF), heart rate, blood pressure and brain waves were measured. The effect of NH3 (4ppm) and H2S (0.12ppm) on the above physiological functions was also studied. Odorant concentration in the range of detection threshold did not cause any significant change in TAF, heart rate, blood pressure and brain waves, but odorant concentration over recognition threshold affected the above physiological functions. From these results, it may be presumed that the acceptable limit of odor concentration exhibiting the lowering of physiological functions is in the range of recognition threshold. This limit of odor intensity may correspond to three point five according to the six-points intensity scale.

Optimal performance in conveyer system from a viewpoint of the physiological functions

The optimal performance was studied on the inspection and vigilance tasks for measuring steel pins. The subjects were eight healthy male students. Four of them measured the diameter of steel pins in conveyor system as well as in non-conveyor system (inspection task group). The other four watched the performance of the above inspection task (vigilance task group). In conveyor system, the both groups were engaged in their tasks for 30min. and 120min. under three different conditions as 20cm, 30cm and 40cm of the station-interval between the steel pins. In non-conveyor system, they were engaged in their tasks for 120min. only.The results obtained were as follows:1) The performance on the inspection and vigilance tasks in non-conveyor system was significantly better than that in conveyor system.2) In conveyor system, both inspection and vigilance tasks were performed most effectively at the station-interval of 30cm.3) The TAF (the function of concentration maintenance) and FF (flicker frequency) tests showed that the body burden in vigilance task was greater than that in inspection task.

Studies on the function of concentration maintenance (TAF). 12. Changes of TAF due to muscular work

Our previous studies on the evaluation of mental stress by means of the TAF-test and experiments on TAF in relation to the brain waves indicated that the TAF may be a reasonable indicator of the state of central nervous activities. As to physical fatigue, the present studies have been carried out so as to know to what extent the change in TAF could be caused by muscular work.By the use of ergometer, three kinds of muscular works (light-work for 300 minutes, heavy-work for 30 minutes and long middle-work for 120 minutes) were given to 22 healthy male students at three-day rest intervals.Before and after the work load, the examinees were administered the TAF-test, brain-wave (α-wave) recording, knee-reflex and several other physiological function tests, and the expiratory gases were analyzed to measure the intensity of the load.The results obtained were as follows:1. Following the work-administration, the function of concentration maintenance (TAF-L) lowered in the heavy and long-middle works, while it increased in the light work.2. The lowering in TAF after the work-administration significantly correlated with the volume of oxygen consumed in muscular work, that is, the greater the latter the greater the former.3. In the extent over 650ml/min, of O2 consumption, the increase showed a significant correlation with that of the alpha-wave appearance in the brain waves.4. The threshold value of knee-reflex significantly increased after the work-administration in all three kinds of physical loads using ergometer.

Function of concentration maintenance (TAF). Rept. XIX. : Weekly changes of TAF

Function of concentration maintenance (TAF). Rept. XIX. : Weekly changes of TAF

Studies on the Function of Concentration Maintenance (TAF) : (Rept.15) With Special Emphasis on the Activity-level of the Cerebral Cortex

Studies on the Function of Concentration Maintenance (TAF) : (Rept.15) With Special Emphasis on the Activity-level of the Cerebral Cortex

Studies on the Function of Concentration Maintenance (TAF) (18) Influences of Continuous and intermittent Noise

Studies on the Function of Concentration Maintenance (TAF) (18) Influences of Continuous and intermittent Noise

Diurnal and seasonal variations in the function of concentration maintenance (TAF)

The purpose of this study was to clarify the diurnal and seasonal variations in TAF.The subjects were 5 healthy men aged 30-37 years old. The measurements of TAF were carried out from a.m. 5°30′ to p.m. 9°30′ at intervals of 4 hours and in this study, the examinee aimed at the target of the Takakura's apparatus for 15 minutes continuously in each time. TAF-L and -D were computed from the standardized curve and the coefficient of variation was computed from TAF-L and -D. The duration of concentration maintenance, which is the total duration of aiming level better than 2.5 in the standardized curve, was measured.The experiments were made in July and in February on the same subjects.The following results were obtained;1) As the diurnal variation, it was observed that the mean regulatory range in the feed back system concerning with the target aiming became rough at 1°30′ p.m., but the relative reliability to exhibition of the feed back oscillation on this range became high.2) As the seasonal variation, it was certain that the mean regulatory rane in the feed back system concerning with the target-aiming became more rough in summer than in winter, and that the hypofunction in the feed back system was remarkable on the afternoon in summer according to the observation of the duration held above the TAF-L of 2.5.

Studies on the Function of Concentration Maintenance (TAF) [XII] : As to the Pharmacological Effect of γ-Oryzanol

Studies on the Function of Concentration Maintenance (TAF) [XII] : As to the Pharmacological Effect of γ-Oryzanol

STUDIES ON THE FUNCTION OF CONCENTRATION MAINTENANCE (TAF). DISCUSSION ON THREE-MINUTE METHOD OF THE TAF-TEST

The function of concentration maintenance (TAF), the concept of which was presented by Takakuwa in 1960, is originally described as TAF-L and TAF-D computed from the standardized curve in three-minute method of the TAF test. A number of studies on TAF showed that the changes of TAF-L and TAF-D were corresponding to the degree of fatigue resulting from work, especially characterized by mental stress. Another experiment demonstrated the close correlation existing between TAF and the autonomic nervous balance. However, the central nervous functions are very complicated and multifactorial, so that the observations have been advanced as to what the TAF-L and TAF-D in three-minute method are indicated.The present studies were devided into three series. The first one consists of original three-minute method, then rest for five minutes and aiming for five minutes, then rest for one minute and aiming for three minutes. For the second, aiming for three minutes and rest for thirty seconds are repeated six times, and continuous aiming for eighteen minutes is given on the other day. The third one is the measurement of galvanic skin reflex in parallel with the original three-minute method. The results of these observations suggested the following points:1) TAF-L in three-minute method indicates the process of the body to be brought into the status of concentration maintenance.2) There are large individually characteristic differences in the processes to the status of concentration maintenance, some one quick and some other slow.3) The duration of concentration maintenance, which is the total duration of aiming level better than 2.5 in standardized curve, is significantly correlated with the value of L in continuous aiming.

Studies on the Function of Concentration Maintenance (TAF) : An Effect by Jet Flight (Part 8)

Studies on the Function of Concentration Maintenance (TAF) : An Effect by Jet Flight (Part 8)

Studies on the Function of Concentration Maintenance (6) : School Examinations and Tranquilizing Effect

Studies on the Function of Concentration Maintenance (6) : School Examinations and Tranquilizing Effect