The interference of various word parts on color naming in the Stroop test

Abstract

This study compared the interfering effects of various word parts on performance of the Stroop task. In different conditions, the first, middle, and last two letters of a color word formed color patches. In other conditions, random letters were attached to these word parts. In a control condition, entire words formed the color patches. While no condition produced as much interference as the control condition, the first part of a color word interfered with color naming more than other word parts. The addition of unrelated letters had little or no effect on the interference produced by the first part of a word. The results are consistent with suggestions that word perception often involves the activation of an articulatory motor program which is initiated by the first part of the word.Several lines of research on word processing indicate that competent readers do not encode words by a letter-by-letter process. Research by Reicher (1969) and Wheeler (1970) demonstrated that subjects recognized single letters in tachistoscopically presented words with significantly greater accuracy than when the letter was embedded in randomly generated strings of letters or when the letter appeared by itself. One might conclude that competent readers process words as single units. Another interpretation. often suggested from psycholinguistic approaches to reading (Smith. 1973) and recently supported by experimental evidence (Thompson & Massaro. 1973). posits that a competent reader capitalizes on the redundancy of probable relations between letters in English orthography. That is. the probabilistic nature of spelling patterns. or the fact that certain letters occur together frequently. allows the competent reader to intelligently guess that a letter will occur in a given letter sequence. As an obvious example. the letter "q" imposes severe restrictions on the subsequent few letters in a word. If words are considered as left-to-right sequences of letters. then the first letter imposes more constraints and thus provides more information than subsequent letters. If letters are perceived in a left-to-right sequence, then the first letter should be the most important.Empirical support for this description of the reading process is provided by a recent study by Eriksen and Eriksen (1974 sequentially presented in two segments such that one of the letters was delayed by an interval of 0 to 500 msec, and subjects were required to pronounce the words as rapidly as possible. It was found that delay of the first letter was detrimental to performance. while delay of any of the other letters facilitated performance. Since this facilitation was dependent on whether the first letter had a constant pronunciation that was not dependent on the subsequent letters. it was concluded that the perceptual processing was associated with the activation of a motor program for pronouncing the word.The purpose of the present study was to test the reported importance of the first letters in processing words using several variations of the Stroop test. If the fir...

Stroop interference and negative priming: Problems with inferences from null results

“…First, Beech, Agar, and Baylis (1989) found that the Stroop effect from incongruent words disappears when compared with nonwords that share the first two letters with the incongruent word. In addition, other studies have reported that just the first two letters of an incongruent word are sufficient to produce interference effects (Bibi, Tzelgov, & Henik, in press;Coltheart, Woollams, Kinoshita, & Perry, 1999;Regan, 1978;Singer, Lappin, & Moore, 1975). From this, it appears that the absence ofa Stroop effect with this nonword condition is an expected pattern, rather than an exception.…”

Stroop interference effects in partially colored Stroop words

“…This pattern supports the idea that single-letter coloring in the Stroop task attenuates Stroop interference in a position-sensitivemanner. We suggest that Stroop interference was larger when the end of the word was colored than when the beginning of the word was colored because when the end of the word was colored the initial letter segment, which most strongly activates responses (Singer et al, 1975), was longer (blu in the word blue) than when the beginning of the word was colored (b in the word blue).…”

“…First, Singer, Lappin, and Moore (1975) found that naming latencies for word lists were longer when the items were color names incongruent with their ink color, and with their middle or final letters deleted or altered (e.g., orxxge, or, and oranxx), than when the items were color names incongruent with their ink color and with their initial or middle letters deleted or altered (e.g., xxange, an, and ge). More recently, Coltheart et al (1999) observed faster color naming when the first phoneme was shared between a nonsemantically related word and a color word and the ink color was the same as that indicated by the first phoneme (e.g., ram and hip instead of red colored in red), than when the last phoneme was shared (e.g., bed instead of red colored in red).…”

Components of Stroop-like interference in picture naming

“…This constraint could not be perfectly met. Care was taken, however, that none of the words had the same initial letter as the verbal label of the accompanying picture (for the importance of the first letter, see, e.g., Lupker, 1982;Posnansky & Rayner, 1977;Regan, 1978;and Singer, Lappin, & Moore, 1975). (3) In the distractor conditions, RELlNRS and UNRlNRS pictures were not to be combined with words that denote objects that show a large visual similarity to the target picture.…”