How does practice modulate fake-production costs in a basketball task? Analyses of frequency distributions and mixture effects

The execution of incompatible actions imposes costs on action planning, commonly known as response-response incompatibility-costs. This phenomenon is also evident in sports: A basketball player who performs a pass in one direction whilst orienting the head into the contrary direction (pass with head fake) needs more time to initiate the action as if pass direction and head orientation are the same (pass without head fake).The aim of this study was twofold: First, we present a re-analysis of the data from Böer et al. (Psychological Research 88:523-524, 2024) using mixture effect modelling (Miller, Behavior Research Methods 38:92-106, 2006) explore if fake-production costs manifest continuously (uniform effect) in all participants or if some participants show fake-production costs occasionally but substantially (mixed effect). Second, we collected data of a control group which was analysed with the previous data of the practice group and fitted initiation times (ITs) to an ex-Gaussian distribution.The analysis of mixture effects revealed that most participants exhibited a uniform effect when they didn't have time to mentally prepare the movement. This pattern was not changed by practice, suggesting fake-production costs can't be overcome by practice alone without mental preparation time.The analysis of mean ITs revealed improvements in the practice group but not in the control group, independent of the type of pass performed. The distribution analyses complemented these findings as it showed that the improvement in participants' performance with increasing practice can mainly be attributed to a reduction of the exponential part of the distribution (parameter tau).