Brain slow waves preceding time-locked visuo-motor performance.

According to previous findings (Konttinen and Lyytinen, 1992), the slow brain negativity preceding the trigger pull in rifle-shooting tends to be decreased in successful shots among experienced marksmen, whereas no such pattern is found among inexperienced subjects. This effect was interpreted as resulting mainly from optimal arousal. However, another explanation is examined here. The aim of the experiment was to investigate slow electrocortical changes associated with motor regulation and visual aiming related to shooting performance. Four variations on a shooting task were used, in which the visual and motor components were contrasted. Motor activity related to gun stabilization was found to be associated with slow-wave positivity, whereas visual aiming was manifested as slow negativity. The results offer some basis for interpreting the individual slow brain wave patterns that predict shooting performance.