Verbal interference with encoding in a perceptual classification task

Altered the Stroop test to require the binary classification of colors. Although the required verbal responses ("yes" and "no") bore no direct semantic relation to the printed words, interference with the classification response was still obtained from 36 undergraduates. The interference seemed to be at the stage of implicit color identification or coding rather than at the stage of overt response competition. G. S. Klein's (see 39:5) interpretation of the encoding process is discussed. (15 ref.) (PsycINFO Database Record (c) 2006 APA, all rights reserved).