The Simon task as a measure of response inhibition

The purpose of this report is to illustrate the view, on the basis of existing research, that the Simon effect arises during the course of output processing (output locus), and, in particular, that it can be used to assess one's ability to prevent the initiation of unwanted response urges (i.e. initiation inhibition ability). The major contention expressed is that the 'response precue' procedure and data, most commonly recruited as support for a Simon effect output locus, is likely to be unsuitable for this purpose, and that other sources of experimental evidence are more appropriately used for this function.