useR! 2024

The neural correlates of learning are frequently explored in neuroscience research, typically through learning-induced changes in the mean of a response variable. Motor skill learning can enhance neural communication between the brain and the trained muscle. This communication is typically assessed by inducing muscle contractions in the trained pathway and measuring changes in mean size over time, with larger measurements suggesting enhanced communication. Motor learning may also improve the efficiency of this communication, possibly reflected by more consistent muscle contractions and a reduction in the within-individual variability of these measurements over time. This study explored how motor skill learning and a subsequent intervention (active vs. placebo) influenced changes in the mean size and within-individual variability of these measurements. Effects were estimated by fitting a location and scale model using the GAMLSS package in R. GAMLSS fits a distributional model, which can estimate all parameters for the specified distribution. The results and analysis pipeline from this study will be discussed, emphasising the utility of the GAMLSS model in this research.