Influence of Prior Use of the Same or Different Effectors in a Reaching Action

Abstract

[EN]Use of diff erent eff ectors in two consecutive actions could generate an attentional shift between the eff ectors with shorter latencies in the second action of reaching. 18 participants (10 men; M age = 21.3 yr.) participated in an experiment with two main variables: (1) eff ector switching with two levels (Switching and No Switching), where the participants use or do not use a diff erent motor eff ector for each action; (2) lifting muscles, i.e., the muscles involved in the fi rst phase of the reaching, with two levels (fi nger-lifting muscle and palm-lifting muscle). Premotor time, Motor time, Reaction time, Movement time, and Total time were measured. For Premotor, Movement, and Total times, faster responses were observed when there was no switching of the eff ector. This delay could be due to an attentional shift between motor eff ectors and its relations with motor processes. Possible applica tions include the ergonomic design of device controls, considering that the use of the same eff ector is benefi cial when fast reaction times are sought.