The process-dissociation procedure was used to estimate the influence of spatial and form-based processing in the Simon task. Subjects made manual responses to the direction of arrows . The results provide evidence that the form and spatial location of a single stimulus can have functionally independent effects on performance. They also indicate the existence of two kinds of automaticity—an associative component that reflects prior S-R mappings and a nonassociative component that reflects the correspondence between stimulus and response codes.