Three experiments investigated the basis for the-McGurk effect" whereby opticallyspecified syllables experienced synchronously with acoustically-specified syllables integrate in perception to determine a listener's auditory perceptual experience. One hypothesis is that the effect arises when optical and acoustic cues for a syllable are associated in memory. A second hypothesis is that the effect arises when cross-modal information, familiar or not, is convincingly about the same articulatory speech event in the environment. Experiments contrasted the cross-modal effect of orthographic syllables on acoustic syllables, presumed to be associated in experience and memory, with that of haptically-experienced and acoustic syllables, presumed not to be associated. Findings were that the latter pairing, but not the former, gave rise to cross-modal influences under conditions in which subjects were informed that cross-modal syllables were paired independently. Mouthed syllables felt by a perceiver affected reports of simultaneously heard syllables (and reports of the mouthed syllables were affected by the heard syllable). These effects were absent when syllables were simultaneously seen (spelled) and heard. We conclude that the McGurk effect does not arise due to association in memory, but rather to conjoint near specification of the same causal source in the environment..in speech, the moving vocal tract producing phonetic gestures.

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The goal of this study was to compare children's and adults eyewitness identification accuracy when presented with an array of possible suspects (‘lineup’) versus one suspect (‘showup’). Kindergarten children and adults were shown a slide show of a staged theft and subsequently asked whether, of the photo or photos shown them, the perpetrator was present or not. Children were more likely than adults to identify the perpetrator correctly when that suspect was present in the lineup or showup. Children were also more likely than adults to make an incorrect identification of another person when the perpetrator's photo was not present in the lineup or showup. Because false positive identification errors are more difficult to detect with the showup than the lineup, use of the showup may be less appropriate with child witnesses than with adults due to children's greater tendency to make positive identifications.

Three experiments follow up on Easton and Basala's (1982) report that the "McGurk effect" (an influence of a visibly mouthed utterance on a dubbed acoustic one) does not occur when utterances are real words rather than nonsense syllables. In contrast, with real·word stimuli, Easton and Basala report a strong reverse effect whereby a dubbed soundtrack strongly affects identification of lipread words. In Experiment 1, we showed that a strong McGurk effect does obtain when dubbed real words are discrepant with observed words in consonantal place of articulation. A second experiment obtained only a weak reverse effect of dubbed words on judgments of lipread words. A final experiment was designed to provide a sensitive test of effects of lipread words on judgments of heard words and of heard words on judgments of lipread words. The findings reinforced those of the first two experiments that both effects occur, but, with place-of-articulation information discrepant across the modalities, the McGurk effect is strong and the reverse effect weak.In the "McGurk effect," first observed by McGurk and MacDonald (1976; see also MacDonald & McGurk, 1978), a listener's perceptual report of a heard nonsense syllable can be influenced by the sight of a speaker producing a different syllable. In one experiment, MacDonald and McGurk dubbed a videotape in which a speaker produced various consonant-vowel (CV) syllables. On the dubbed tape, the mouthed syllable and the syllable on the soundtrack were discrepant. Syllables that subjects reported hearing were influenced by the mouthed syllable.For example, mouthed ldal paired with acoustic lmal was most frequently identified as "na." The manner-place hypothesis put forth by MacDonald and McGurk seems to account for much of the data (but see Summerfield, 1987, for some qualifications). The hypothesis suggests that the acoustic signal dominates in perception of manner of articulation (and voicing) where optical information is poor or absent. In contrast, optical information dominates in perception of those places of articulation that are visibly apparent.Although an effect of visual information was not anticipated by any theory of speech perception, a natural accounting of it is available in at least three current theories.

This research was designed to learn if children's relationships with interviewers might influence the accuracy of their eyewitness memory'and their ability to make identifications from lineups. In two experiments, kindergarten children (5-year-olds) viewed a slide show depicting a minor theft. Children were then interviewed by either their own parent or an unfamiliar experimenter with either a target present or target absent simultaneous photographic lineup. When lineups were presented by parents, children were less accurate, changed their identifications more frequently, and were more likely to acquiesce with a suggestion about an alternative identification. Children showed poorer recall of the event when interviewed by their parent in an unstructured interview (Experiment 1); however, no differences were observed when parents and experimenters followed the same script (Experiment 2). Overall, the results indicate that interviewers can influence the accuracy and consistency of children's eyewitness identifications.Recently, there has been increasing interest in young children's ability to serve as competent eyewitnesses (Ceci,