Reassessing the electrophysiological evidence for categorical perception of Mandarin lexical tone: ERP evidence from native and naïve non-native Mandarin listeners.

Some studies have argued that native speakers of tonal languages have been shown to perceive lexical tone continua in a more categorical manner than speakers of non-tonal languages. Among these, Zhang and colleagues (NeuroReport 23 (1): 35-9) conducted an event-related potential (ERP) study using an oddball paradigm showing that native Mandarin speakers exhibit different sensitivity to deviant tones that cross category boundaries compared to deviants that belong to the same category as the standard. Other recent ERP findings examining consonant voicing categories question whether perception is truly categorical.

Suppression of vocal responses to auditory perturbation with real-time visual feedback.

Speakers can adjust pitch using auditory feedback through a short-latency corrective response known as the pitch-shift response (PSR). Suppression of the PSR denotes on-line stabilization of pitch. In this paper, the hypothesis that pitch-shift responses can be suppressed with real-time visual feedback of vocal F0 is investigated.

Rhythm measures and dimensions of durational variation in speech.

Patterns of durational variation were examined by applying 15 previously published rhythm measures to a large corpus of speech from five languages. In order to achieve consistent segmentation across all languages, an automatic speech recognition system was developed to divide the waveforms into consonantal and vocalic regions. The resulting duration measurements rest strictly on acoustic criteria.

A quasi-glottogram signal.

A novel, noninvasive experiment is proposed that reliably shows the strength of glottal oscillations. The quasi-glottogram (QGG) signal is generated from a microphone array that is trained to approximate the electroglottogram signal. The QGG may be useful to improve estimates of whether speech is voiced, to quantify partial voicing, and to reduce the phoneme effect when measuring the amplitude of speech signals.