Intentional pre-cueing does not influence the Simon effect

Choice reactions can be performed more quickly if the response corresponds spatially to the stimulus, even when the stimulus location is irrelevant for the task (Simon effect). It is assumed that the Simon effect is related to interference between spatial stimulus and response codes in a response selection stage. A central finding for such a response selection account is the increase in the effect if the most probable response location is given in advance by an intentional pre-cue. However, Hasbroucq and Possamaï (1994) assumed that the increase in the Simon effect in such a task may be due to an unmeant pre-cueing of the stimulus location, which has been recently supported by an electroencephalography (EEG) study by Wascher and Wolber (2004). In the present study this notion has been tested experimentally. In Experiment 1, a centrally presented symbolic cue served as an intentional cue. As a result, the enhancement of the Simon effect in valid cueing almost disappeared. When tactile cues were used (Experiment 2), the increase in the Simon effect disappeared completely. Thus, the influence of intentional cueing reported in previous studies can be assigned to attentional factors and does not support a response selection account.