A STUPY ABOUT MOTOR-RETENTION OF THE FLEXION AND EXTENSION OF THE FORE-ARM / 体力科学

ABSTRACT

The purpose of this study is to clarify the characteristics of the short-term motor-memory and to analyze various loads effect of motor-retention in the exercise of flexion and extension of the fore-arm. As the means of analysis, correlation function between command and response waves was used efficiently and furthermore the electric computer system helped to investigate motor-retention. Many experimental conditions were decided to 0.1-0.8 Hz of one's exercise rhythm, 0-0.5 kg of loads attached to the fore-arm, and 3-6 cm of exercise displacement. Three healthy persons were employed as subjects.<BR>As the results of this study, following points were shown clearly.<BR>(1) After the fore-arm was exercised to the flexuous and extensional directions for 25 sec., response waves of motor-retention were recorded to Data-recorders for 60 sec Quantitative analysis of this motor-retention became effective by using the method of correlation function.<BR>(2) About exercise rhythm (frequency), the rapidity of fore-arm exercises in the retentive learning was 0.05 Hz slower than that of these exercises in the begining learning.<BR>(3) About the transfer gain of these exercises between command and response waves, two motor-gains of the retentive and begining learning were shown the same values only when these exercises were practised at experimental conditions of 0.8 Hz frequency and 0.5 kg load.<BR>(4) Motor-retention rate, that was calculated from error values of performance, was dropped down such as about 0.3 rate in proportion to the time elapsed of recollection and also to rhythm-slownes of the command frequency.<BR>(5) Optimal exercise displacement of the fore-arm was proved to the median of 6 and 3 cm in order to reappear the length memorized by the begining learning.<BR>(6) Discharged voltages of the integrated EMG in Flexor and Extensor C arpi Radialis were recorded lower at the time, when motor-retention was displayed rightly and exactly.<BR>(7) Sychological reminiscence and this motor-retention were shown quite opposite results in the learning points of reaction time, rhythm, strength and displacement, because the former was dependent upon the memory in the central nervous system (brain cortex), while the latter relied upon the memory in the peripheral-nervous system (receptor) .