This three-part study demonstrates that perceptual order can influence the integration of acoustic speech cues. In Experiment 1, the subjects labeled the lsl and If] in natural FV and VF syllables in which the frication was replaced with synthetic stimuli. Responses to these "hybrid" stimuli were influenced by cues in the vocalic segment as well as by the synthetic frication. However, the influence of the preceding vocalic cues was considerably weaker than was that of the following vocalic cues. Experiment 2 examined the acoustic bases for this asymmetry and consisted of analyses revealing that FV and VF syllables are similar in terms of the acoustic structures thought to underlie the vocalic context effects. Experiment 3 examined the perceptual bases for the asymmetry. A subset of the hybrid FV and VF stimuli were presented in reverse, such that the acoustic and perceptual bases for the asymmetry were pitted against each other in the listening task. The perceptual bases (i.e., the perceived order of the frication and vocalic cues) proved to be the determining factor. Current auditory processing models, such as backward recognition masking, preperceptual auditory storage, or models based on linguistic factors, do not adequately account for the observed asymmetries.Studies of speech perception have revealed that theacoustic cues that support perception of individual phonetic segments are overlapped and interwoven. Even in fricativevowel (FV) syllables such as sa, sha, su, and shu, where the vocalic portion is associated with the vowel and the frication portion with the fricative consonant, the vocalic portion contains perceptual information for the fricative as well as for the vowel (e.g., Mann & Repp, 1980). Likewise, the frication portion may contain information for the vowel (e.g., Yeni-Komshian & Soli, 1981). This spread of segmental information is attributed to the coarticulation of articulatory gestures for adjacent segments and has led some researchers to suggest that speech perception proceeds as if by reference to the way in which speech is produced (see Liberman & Mattingly, 1985;Mann & Repp, 1980). Previous studies of segmental perception in FV utterances have illustrated that listeners readily make use of acoustic information spread across the entire utterance. These studies provoke questions about the spread of segmental information in other combinations of segments and about how listeners integrate and weight this information in their perceptual judgments. The present research attempts to address these questions by comparing the effect of vocalic context on the perception of fricatives in FV and vowel-fricative (VF) stimuli. This comparison allowed us to determine how the order of vowel and fricative segments in an utterance influence the integration and weighting of information spread over the utterance.FV and VF syllables have several advantages for the proposed comparisons. The vocalic (periodic) and the frication (aperiodic) portions of a syllable can easily be separated, and either portion can ...