Some sources of artifact in studies of the tachistoscopic perception of words.

Abstract

A methodological study of tachistoscopic word thresholds. Stimuli were 5-letter words varying in frequency; Ss were male undergraduates. Experimental groups varied: (a) stimulus presentation--random or repeated, (b) size of stimulus population--list or no list, (c) stimuli per exposure--1 or 2, (d) task--identification or discrimination, and (e) response--forced or free. Frequency affected identification thresholds only when Ss had no word list. Identification of the first letter of the words showed no frequency effects. Identification thresholds were lower than discrimination thresholds. The forced-response method lowered identification thresholds for Ss with word lists. The relevance of the findings for studies of perceptual defense, vigilance, and subliminal perception was pointed out. (19 ref.) (PsycINFO Database Record (c) 2006 APA, all rights reserved)