Abstract des Autors

The aim of this study was to obtain information on the maturation of central and peripheral nervous system in children and adolescents by means of neuro-motor reaction time (NMRT) and of the muscle movement velocity (MV) in response to the onset of a visual stimulus. NMRT and MV were studied in 558 normal non-athletes boys whose ages ranged from 6 to 19 years, divided in seven age groups of two years each (from 6-7 to 18-19). NMRT and MV were assessed at 3 different levels of difficulty: a) simple (SNMRT and SMV), b) choice (CNMRT and CMV), and in a group of subjects also c) in the presence of an acoustic interference ("noise") arising immediately after the visual stimulus (SNMRT+n and CNMRT+n). The results, both in SNMRT and SMV and CNMRT and CMV are expressed by the following equations: SNMRT (in msec) = 1.0539 x age**2 = -37.70 x age + 591.83; SMV (in m/sec) = -0.0046 x age**2 + 0.146 x age + 0.5015; CNMRT (in msec) = 2.672 x age**2 = -80.44 x age+1016; CMV (in m/sec) = -0.0048 x age**2 + 0.149 x age + 0.3986. These polynomial equations describing the relationship with age are different since they show an increased delay both in CNMRT and in CMV compared with SNMRT and SMV respectively. In the presence of the acoustic "noise", a further delay in SNMRT+n and CNMRT+n in all the subjects occurred. Results both from electrophysiology and of the present study of SNMRT show a significant maturation connected with age, both in the neuro-motor reaction time and in the muscle movement velocity. The likelyhood of increasing the reaction time velocity and muscle velocity in young subjects by specific training seems to be possible only if levels of attention, motivation (CNMRT) and concentration (SNMRT+n and CNMRT+n) are raised. Verf.-Referat