Competing responses and the processing of irrelevant information.

A number of studies have shown that performance of identification and discrimination tasks is detrimentally affected by irrelevant information, yet other studies have failed to find such decrements. It is suggested that these contradictory findings depend on whether S must make difficult discriminations among the relevant stimuli, the irrelevant stimuli, or between the relevant and irrelevant stimuli. The role of irrelevant information in these tasks is to enhance or amplify the competihg responses engendered by the difficult discriminations. Irrelevant information enhances competing responses by increasing the information processing requirements of a task. The results of various studies of irrelevant information seem to be in good agreement with the assertions.