A response-selection basis for the mixed-category, repeated-stimulus inferiority effect.

Abstract

When subjects identify a target stimulus with an assigned keypress response, flanking noise stimuli produce interference if they signal an alternative response and slight facilitation if they are identical to the target. However, when the possible stimuli come from two distinct categories Getters and digits), interference also occurs if the noise letters are identical to the target. Four experiments were conducted to determine whether this mixed-category, repeated-stimulus inferiority effect is due to stimulus-identification or response-selection processes. The inferiority effect was (1) absent when letters were assigned to one response and digits to another; (2) absent when the target stimulus was named, rather than identified by a keypress response; and (3) eliminated when subjects practiced with mixed assignments of letters and digits. These findings converge on a response-selection basis for the inferiority effect.