ABSTRACT
The effects of varying time intervals and frequency of preliminary stimulations shown in advance of movements upon the variations in the subsequent responses to exogenous stimulations have been evaluated on the basis of the reaction time. The following results have been obtained.<BR>1. In the cases of simple preliminary reactions, if a time interval between the preliminary stimulations and the actual stimulations was less than 1000 msec, the reaction time was delayed more than the cases of the control reaction to simple stimulations. A relationship of index function was found out between the intervals of stimulations and the time of responses.<BR>2. In the cases of persistent preliminary reactions, the shorter the intervals of stimulations, the shorter became the reaction time than that of the control reaction to the simple stimulation.<BR>3. The so-called flying errors which are the movements induced before the actual stimulations were most frequently developed at an interval of stimulations of 1000 msec.<BR>On the basis of the above findings of the reactions, the levels of excitements in the center (CNS) and peripheries could be assessed on the basis of the above findings of the reactions that reactions to a stimulation can be variable according to the other stimulations induced prior to the particular stimulation.
ABSTRACT
In order to find out what changes would happen to the cancelling in the course of the program and what differences would be caused in the cancelling ability depending on the degree of program formation, we examined the changes of adults (in their 20s and 50s) and children, and obtained the following results.<BR>1. In the cases of cancelling actions halfway, delays in the reaction time and movement time of both the adults and children were found, unlike the cases of controlling actions. This tendency was noted remarcably in the adults at their age of 20s and in the children.<BR>2. The time for the switching into the next actions by cancelling the previous actions was found to be the longest at the initial stage when the action program was intiated.<BR>3. The fluctuation in the movement times immediately after initiating actions was extremely small in both controlling and cancelling actions. However, as the actions advanced, the values of the cancelling actions showed larger fluctuations. This trend could be noted very significantly in both the adults at the age of their 20s and the children.<BR>4. The time of delays by more than 20 over the mean value in both the time for reaction and the time for movements were noted more frequently in the cancelling actions especially in the latter half of the actions where the actions advanced.<BR>5. The emergence of erroneous action (miss-touch) for cancelling to stop the actions and to push the next key instead was the most frequent when the cancelling was made at the initial stage of the action, and the rate of miss-touch was invariably approx. 50% at any age. As the actions advanced, the frequency of miss-touch decreased.<BR>On the basis of the above findings, it can be concluded that the earlier it is in the course of proceeding with the program, the more it is difficult to cancel the program in the central nerve system for cancelling the on-going action, and that, as the program advaces, it is easier to cancel the program. It was furthermore demonstrated that, as the age advanced, the program could be formed more firmly, making it difficalt to cancel the program.
ABSTRACT
The motions are manifested by the built-in motion programing within the central nerve system. It was investigated by means of a simple keypushing motion on what variations in the motions would be developed by alterations in the programing. The key-pushing motion consists in pushing two or four keys in designated orders according to the photic stimulation, and the reaction time and motion time in this case were determined. The key-pushing was performed in accordance with the 4 types of programing.<BR>The results were as indicated hereunder.<BR>1) The motion time was shorter when the number of keys to be pushed is less in comparison with the larger number of the keys.<BR>2) The variations in the programing within the central nerve system are more influential upon the initial stage of the motion, i. e. the pushing procedures of the first and the second keys.<BR>3) The delays in the reaction time were more remarkable in children in any programing than in the adults. The errorneous key-pushing motion was more frequently noted in the action to push the first key.
ABSTRACT
In order to investigate the development of cooperatively responsing ability the subjects were made to carry out synchronous and altenate beating of colateral or contralateral hand and foot.<BR>1. The synchronous beating of colateral hand and foot developed earlier than of contralateral hand and foot. In addition, hand-foot cooperative response developed to higher degree at the right side than at the left.<BR>2. The hand-foot cooperative movement developed later in altenate beating with hand and foot than synchronous one. Development of altenate movement was earlier in the contralateral hand and foot than in the colateral and foot. Twenty percent of the adult subjects could not carry out altenate beating with colateral hand and foot.<BR>3. A coefficient of variation in time intervals of beating was decreased with advanced age, but smaller in the synchronous movement than in the alternate one. The coefficient was the largest in the alternate movement of colateral hand and foot in little child. However, it was smaller in both synchronous and alienate movements in the subjects older than 13 years old.<BR>The above findings indicate that the beat movement differs in difficulty depending upon different combinations of hands and feet. This may be determined by the relationship between spinal reflex of four limbs and inhibition of it by the higher system. A movement which needs stronger inhibition and selection of a greater number of reflexes needs a longer time to be mastered. Children can not perform the most difficult colateral altenate movement untill the age of 14 or 15 years.
ABSTRACT
Our interest is to know the learning process of skillness, because more needed to apply the optimum muscle power rather than maximum one in our daily life. The experiment is so simply designed that subjects are only required to land just correctly at the marked line by a bound jump. The width by jumping to reach is only distance of 1/3 body height of each individual.<BR>The jumpings are done in 3 ways : (1) voluntary take off, (2) take off with buzzer signal, (3) jumping with blindfold.<BR>As subjects served boys and girls ranging from 6 to 21 years of age. Distances between maked line and landing point, and times taken by motions are measured, through the electric system with a strain guage which is attached to taking off and landing boad.<BR>The results are shortly concluded as follow ;<BR>(1) In more aged subjects make smaller gaps, which are given as the names of algebraical sum of absolute value of distance from maked line. The subjects of over 15 years of age landed always within small gaps.<BR>(2) Subjects of over 15 years of age take longer time for knee joint extention. In younger subjects (i, e, younger than 15 years of age), time of knee extention is rather shorter, however, they take longer time for just sinking which is accompanied with knee extention.<BR>(3) The jumping action is done in the series of motion of just sinking and extending the knee joint.<BR>Correlationship between knee extention time and just sinking time is significant (r=0.569**), in the subjects of 18-21 years, however no correlationship is obtained in 6-11 years of age.<BR>(4) Jumping with blindfold takes longer distance. The visual feedback seems to take major part in controling. However both ratio of knee extention per time of just sinking in the two ways of jumping i, e, voluntary jumping with open eye and with blindfold is almost same.<BR>(5) In the case of taking off with buzzer signal, subjects incline to land further than voluntary take off. This gives us the suggestion that buzzer sound increases in the excitation on reticular activationg system. Poor coordination in young individuals is likely due not only to lack in cortical realization of motion pattern but to rough synapting of spinal and cortical circuit.