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)
PURPOSE Investigate training-related changes in acoustic-phonetic representation of consonants produced by a text-to-speech (TTS) computer speech synthesizer. METHOD Forty-eight adult listeners were trained to better recognize words produced by a TTS system. Nine additional untrained participants served as controls. Before and after training, participants(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)
Identification and discrimination of lexical tones in Cantonese were compared in the context of a traditional categorical perception paradigm. Three lexical tone continua were used: one ranging from low level to high level, one from high rising to high level, and one from low falling to high rising. Identification data showed steep slopes at category(More)
This study investigated whether cochlear implant users can identify Cantonese lexical tones, which differ primarily in their F0 pattern. Seventeen early-deafened deaf children (age= 4 years, 6 months to 8 years, 11 months; postoperative period= 11-41 months) took part in the study. Sixteen children were fitted with the Nucleus 24 cochlear implant system;(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)
Five commonly used methods for determining the onset of voicing of syllable-initial stop consonants were compared. The speech and glottal activity of 16 native speakers of Cantonese with normal voice quality were investigated during the production of consonant vowel (CV) syllables in Cantonese. Syllables consisted of the initial consonants /ph/, /th/, /kh/,(More)