Preceding syllables are necessary for the accent advantage effect.

The accent advantage effect in phoneme monitoring-faster responses to a target phoneme at the beginning of an L + H*-accented word than to a target phoneme at the beginning of an unaccented word-is viewed as a product of listeners' predictive capabilities [Cutler (1976). Percept. Psychophys. 20(1), 55-60]. However, previous studies have not established what information listeners use to form these predictions [Cutler (1987). Proceedings of the International Congress of Phonetic Sciences, pp. 84-87; Cutler and Darwin (1981). Percept. Psychophys. 29(3), 217-224]. This article presents evidence that at least the information in the syllable immediately preceding a target phoneme is necessary to cue the predictive attention allocation that underlies the accent advantage effect.

The prosodic accent advantage in phoneme detection: Importance of local context.

Previous research (e.g., Cutler, Perception & Psychophysics, 20, 55-60, 1976) has shown that detection of the initial phoneme of a word is speeded when the word is pronounced with a focal accent. This "accent advantage" is also observed when the accented word is replaced by a neutrally accented one. The present two experiments were designed to identify what aspect of the context preceding the target word is the source of this advantage. Both indicated that the advantage can be ascribed to the syllable immediately preceding the target word, rather than some possibly global but more distal attribute of the context. The first experiment used the recordings that had been used by Cutler Perception & Psychophysics, 20, 55-60, (1976) with the addition of a between-subjects manipulation of the local context. In one condition, the syllable immediately before the target word was the one that had been recorded in the sentence context (preceding an accented or an unaccented target word). In the other, cross-spliced, condition, the preceding syllable was exchanged between accented and unaccented contexts. The second (pre-registered) experiment used new recordings and a within-subject manipulation of the pre-target syllable. The studies confirmed and extended the observation that the pre-target syllable rather than some other prosodic aspect of the preceding context is the source of the faster phoneme detections.

Regressive spectral assimilation bias in speech perception.

Speech perception presents a parsing problem: construing information from the acoustic input we receive as evidence for the speech sounds we recognize as language. Most work on segmental perception has focused on how listeners use differences between successive speech sounds to solve this problem. Prominent models either assume (a) that listeners attribute acoustics to the sounds whose articulation created them, or (b) that the auditory system exaggerates the changes in the auditory quality of the incoming speech signal. Both approaches predict contrast effects in that listeners will usually judge two successive phones to be distinct from each other. Few studies have examined cases in which listeners hear two sounds in a row as similar, apparently failing to differentiate them. We examine such under-studied cases. In a series of experiments, listeners were faced with ambiguity about the identity of the first of two successive phones. Listeners consistently heard the first sound as spectrally similar to the second sound in a manner suggesting that they construed the transitions between the two as evidence about the identity of the first. In these and previously reported studies, they seemed to default to this construal when the signal was not sufficiently informative for them to do otherwise. These effects go unaccounted for in the two prominent models of speech perception, but they parallel known domain-general effects in perceptual processing, and as such are likely a consequence of the structure of the human auditory system.

Eye movement evidence for an immediate Ganong effect.

Listeners tend to categorize an ambiguous speech sound so that it forms a word with its context (Ganong, 1980). This effect could reflect feedback from the lexicon to phonemic activation (McClelland & Elman, 1986), or the operation of a task-specific phonemic decision system (Norris, McQueen, & Cutler, 2000). Because the former account involves feedback between lexical and phonemic levels, it predicts that the lexicon's influence on phonemic decisions should be delayed and should gradually increase in strength. Previous response time experiments have not delivered a clear verdict as to whether this is the case, however. In 2 experiments, listeners' eye movements were tracked as they categorized phonemes using visually displayed response options. Lexically relevant information in the signal, the timing of which was confirmed by separate gating experiments, immediately increased eye movements toward the lexically supported response. This effect on eye movements then diminished over the course of the trial rather than continuing to increase. These results challenge the lexical feedback account. The present work also introduces a novel method for analyzing data from 'visual-world' type tasks, designed to assess when an experimental manipulation influences the probability of an eye movement toward the target. (PsycINFO Database Record