Is the relationship of prosaccade reaction times and antisaccade errors mediated by working memory?

The mechanisms that control eye movements in the antisaccade task are not fully understood. One influential theory claims that the generation of antisaccades is dependent on the capacity of working memory. Previous research also suggests that antisaccades are influenced by the relative processing speeds of the exogenous and endogenous saccadic pathways. However, the relationship between these factors is unclear, in particular whether or not the effect of the relative speed of the pro and antisaccade pathways is mediated by working memory. The present study contrasted the performance of healthy individuals with high and low working memory in the antisaccade and prosaccade tasks. Path analyses revealed that antisaccade errors were strongly predicted by the mean reaction times of prosaccades and that this relationship was not mediated by differences in working memory. These data suggest that antisaccade errors are directly related to the speed of saccadic programming. These findings are discussed in terms of a race competition model of antisaccade control.