Priming processes in the Simon task: more evidence from the lexical decision task for a third route in the Simon effect.

Recently, it was proposed that the Simon effect would result not only from two interfering processes, as classical dual-route models assume, but from three processes. It was argued that priming from the spatial code to the nonspatial code might facilitate the identification of the nonspatial stimulus feature in congruent Simon trials. In the present study, the authors provide evidence that the identification of the nonspatial information can be facilitated by the activation of an associated spatial code.

Bidirectional priming processes in the Simon task.

The Simon effect is mostly explained in terms of dual-route models, which imply unidirectional activation processes from stimulus features to response features. However, there is also evidence that these preactivated response features themselves prime corresponding stimulus features. From this perspective, the Simon effect should only occur whenever the response is unequivocally mapped to just 1 stimulus feature (one-to-one mapping).