Evidence in support of word unitization

Abstract

In each of five experiments, the subjects viewed tachistoscopically presented pairs of letters and made speeded comparison judgments on the basis of name identity. On most trials, a noise letter string (word or anagram) was placed directly between the target letters. The results indicated that correct "same" RTs were a function of noise item type and its relation to target letters. Anagrams increased RTs more than their counterpart words, except when the noise word was either unmeaningful or response incompatible with respect to the target letters (e.g., B Tea b). The interference effects were also found to be independent of sequence length. It was posited that the subjects were unable to completely ignore the irrelevant attributes of the displays and that under certain conditions, the subjects were able to identify the noise items in a holistic fashion. The data were interpreted in terms of a unitization hypothesis of word recognition, response competition, and a continuous-flow conception of information processing.In a recent paper, O'Hara and Eriksen (1979) demonstrated the paradigmatic value of a characterclassification task with interference as a means of examining and supporting a unitization hypothesis of word recognition. Their subjects viewed tachistoscopically presented pairs of letters which were physically identical, name identical, or different, and made speeded comparison judgments on the basis of name identity. On some of the trials, noise trigrams composing either nonwords or familiar words appeared between the target letters (e.g., B ODG b or B DOG b). As expected, correct "same" responses were faster for PI than for NI letter pairs. Surprisingly, however, correct "same" reaction times (RTs) were also a function of noise type. Anagrams increased RTs significantly more than their counterpart words. Word noise, on the other hand, failed to appreciably affect RTs compared to the no-noise condition.Since the word and anagram items were composed of the same letters, O'Hara and Eriksen attributed the differential noise effects to the subjects' ability to perceptually unitize the word noise. They posited that a unitized word's featural or memorial representation would not interfere with the comparison task. The anagrams, however, were likely perceived as a group of free-floating letters and processed along with the target letters to the point of incipient response activation. At this juncture, response compe-

Letter and word code interactions elicited by normally displayed words

“…It may be the use of such inter letter or whole word pattern information that allows word code activation to be independent of letter code activation, as indicated in the present findings as well as those of O'Hara (1980).…”

“…Such an argument has been raised by Johnson (1975), and recent support for the independence of letter and word perception has been reported by O'Hara (1980). He found that positioning unrelated letters between two letters to be matched slows down the response, but such interference is greatly reduced or even eliminated when the interpolated letters make up a familiar word.…”

Stimulus-response compatibility affects auditory Stroop interference

“…A. Eriksen & C. W. Eriksen, 1974;C. W. Eriksen & Schultz, 1979;O'Hara, 1980) and have occurred in experiments in which the congruent and incongruent conditions were equated for stimulus-response compatibility (C. W. Eriksen & Schultz, 1979). Although stimulus-response incompatibility is not necessary for response competition to occur, the contribution of stimulus-response compatibility to response competition is not unexpected (Greenwald, 1970;Keele, 1973, chap.…”

Attentional distribution in the visual field duringsame-different judgments as assessed by response competition

“…It also permits us to determine whether there is a single circumscribed area that is attended or whether attention can be simultaneously concentrated on two separated locations in the visual field. The two forms constituting the target pair can be separated by varying distances in both the vertical and horizontal dimensions, and since same-different judgments have been shown to be quite sensitive to response-competition effects (C. W. Keren, O'Hara, & Skelton, 1977;Krueger, 1978;O'Hara, 1980;St. James & C. W. Eriksen, 1991), the extent or two-dimensional shape of the attended area can be assessed by probing the visual field at different locations with response-incompatible noise stimuli.…”