Alexander L. Francis

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Whether or not categorical perception results from the operation of a special, language-specific, speech mode remains controversial. In this cross-language (Mandarin Chinese, English) study of the categorical nature of tone perception, we compared native Mandarin and English speakers' perception of a physical continuum of fundamental frequency contours(More)
A class of selective attention models often applied to speech perception is used to study effects of training on the perception of an unfamiliar phonetic contrast. Attention-to-dimension (A2D) models of perceptual learning assume that the dimensions that structure listeners' perceptual space are constant and that learning involves only the reweighting of(More)
Two groups of listeners, one of native speakers of a tone language (Mandarin Chinese) and one of native speakers of a non-tone language (English) were trained to recognize Cantonese lexical tones. Performance before and after training was measured using closed response-set identification and pairwise difference rating tasks. Difference ratings were(More)
In English, voiced and voiceless syllable-initial stop consonants differ in both fundamental frequency at the onset of voicing (onset F0) and voice onset time (VOT). Although both correlates, alone, can cue the voicing contrast, listeners weight VOT more heavily when both are available. Such differential weighting may arise from differences in the(More)
Learning new phonetic categories in a second language may be thought of in terms of learning to focus one's attention on those parts of the acoustic-phonetic structure of speech that are phonologically relevant in any given context. As yet, however, no study has demonstrated directly that training can shift listeners' attention between acoustic cues given(More)
This study combined behavioral and electrophysiological measurements to investigate interactions during speech perception between native phonemes and talker's voice. In a Garner selective attention task, participants either classified each sound as one of two native vowels ([epsilon] and [ae]), ignoring the talker, or as one of two male talkers, ignoring(More)
The forms, functions, and organization of sounds and utterances are generally the focus of speech communication research; little is known, however, about how the silence between speaker turns shades the meaning of the surrounding talk. We use an experimental protocol to test whether listeners' perception of trouble in interaction (e.g., disagreement or(More)
Two studies explored the role of native language use of an acoustic cue, vowel duration, in both native and non-native contexts in order to test the hypothesis that non-native listeners' reliance on vowel duration instead of vowel quality to distinguish the English tense/lax vowel contrast could be explained by the role of duration as a cue in native(More)
Native speakers of Mandarin Chinese have difficulty producing native-like English stress contrasts. Acoustically, English lexical stress is multidimensional, involving manipulation of fundamental frequency (F0), duration, intensity and vowel quality. Errors in any or all of these correlates could interfere with perception of the stress contrast, but it is(More)
Understanding low-intelligibility speech is effortful. In three experiments, we examined the effects of intelligibility on working memory (WM) demands imposed by perception of synthetic speech. In all three experiments, a primary speeded word recognition task was paired with a secondary WM-load task designed to vary the availability of WM capacity during(More)