Preshot brain slow potential (SP) shifts from frontal, central, centro-lateral, and occipital areas were recorded for 12 national-caliber sharpshooters during rifle-shooting performance. The aim of the study was to examine the intra-and intersubject variation in these SP profiles and to compare the superior performance to the poor performance. The results revealed that each shooter responded with one main SP profile in both performance categories. The other profiles represented outliers rather than substantial variation. The main profiles differed from subject to subject, presumably indicating several shooting styles. Finally, the main profiles related to high and low score shots could be differentiated, but this differentiation varied from subject to subject. The results were interpreted as showing that a shooter tends systematically to carry through a learned performance pattern, which is reflected in the main SP profile of the superior shots. If the shooter fails to follow this pattern, the shot is preceded by different SP changes.
Niilo Konttinen and Heikke Lyytinen are with the Dept. of Psychology at the University of Jyväskylä, Seminaarinkatu 15, SF-40100 Jyväskylä, Finland.