Purpose: The purpose of this study was to investigate the psychophysical boundary used for categorization of voiced-voiceless stop consonants in native Japanese speakers. Method: Twelve native Japanese speakers participated in the experiment. The stimuli were synthetic stop consonant-vowel stimuli varying in voice onset time (VOT) with…

Purpose: This experiment sought to determine whether children's increased susceptibility to nonsimultaneous masking, particularly backward masking, is evident for speech stimuli. Method: Five- to 9-year-olds and adults with normal hearing heard nonsense consonant-vowel-consonant targets. In Experiments 1 and 2, those targets were presented between…

Purpose: The aim of this article is to examine the effects of visual image degradation on performance and gaze behavior in audiovisual and visual-only speech perception tasks. Method: We presented vowel-consonant-vowel utterances visually filtered at a range of frequencies in visual-only, audiovisual congruent, and audiovisual incongruent…

The ability to compute non-adjacent regularities is key in the acquisition of a new language. In the domain of phonology/phonotactics, sensitivity to non-adjacent regularities between consonants has been found to appear between 7 and 10 months. The present study focuses on the emergence of a posterior-anterior (PA) bias, a regularity involving two…

English has a word-minimality requirement that all open-class lexical items must contain at least two moras of structure, forming a bimoraic foot (Hayes, 1995).Thus, a word with either a long vowel, or a short vowel and a coda consonant, satisfies this requirement. This raises the question of when and how young children might learn this…

Perception studies have shown similarities between humans and other animals in a wide array of language-related processes. However, the components of language that make it uniquely human have not been fully identified. Here we show that nonhuman animals extract rules over speech sequences that are difficult for humans. Specifically, animals easily…

Perceptual experiences in one modality are often dependent on activity from other sensory modalities. These cross-modal correspondences are also evident in language. Adults and toddlers spontaneously and consistently map particular words (e.g., "kiki") to particular shapes (e.g., angular shapes). However, the origins of these systematic mappings…

One hypothesis raised by Newport and Aslin to explain how speakers learn dependencies between nonadjacent phonemes is that speakers track bigram probabilities between two segments that are adjacent to each other within a tier of their own. The hypothesis predicts that a dependency between segments separated from each other at the tier level cannot…

To date, the nature of the phonological deficit in developmental dyslexia is still debated. We concur with possible impairments in the representations of the universal phonological constraints that universally govern how phonemes co-occur as a source of this deficit. We were interested in whether-and how-dyslexic children have sensitivity to…

Adults can rapidly learn artificial phonotactic constraints such as /"f"/ "occurs only at the beginning of syllables" by producing syllables that contain those constraints. This implicit learning is then reflected in their speech errors. However, second-order constraints in which the placement of a phoneme depends on another…

The goal of this study was to explore whether viewing the speaker's articulatory gestures contributes to lexical access in children (ages 5-10) and in adults. We conducted a vowel monitoring task with words and pseudo-words in audio-only (AO) and audiovisual (AV) contexts with white noise masking the acoustic signal. The results indicated that…

Listeners of various languages tend to perceive an illusory vowel inside consonant clusters that are illegal in their native language. Here, we test whether this phenomenon arises after phoneme categorization or rather interacts with it. We assess the perception of illegal consonant clusters in native speakers of Japanese, Brazilian Portuguese,…

This dissertation takes up the issue of transparency and opacity in vowel harmony--that is, when a segment is unable to undergo a harmony process, will it be skipped over by harmony (transparent) or will it prevent harmony from propagating further (opaque)? I argue that the choice between transparency and opacity is best understood as a…

In a noisy environment, visual perception of articulatory movements improves natural speech intelligibility. Parallel to phonemic processing based on auditory signal, visemic processing constitutes a counterpart based on "visemes", the distinctive visual units of speech. Aiming at investigating the neural substrates of visemic processing in a…

Purpose: The present study was designed to investigate the relation of formant transitions to place-of-articulation for stop consonants. A speech production model was used to generate simulated utterances containing voiced stop consonants, and a perceptual experiment was performed to test their identification by listeners. Method: Based on a model…