Current theoretical approaches differ in their assessment of the influences of biomechanical and perceptual factors on speech production. This dissertation investigates these influences on the relative timing of the two gestures typically involved in the production of American English laterals: tongue tip raising and tongue dorsum backing.…

Listeners rapidly adjust to talkers' pronunciations, accommodating those pronunciations into the relevant phonemic category to improve subsequent perception. Previous work has suggested that such learning is restricted to pronunciations that are representative of how the speaker talks (Kraljic, Samuel, & Brennan, 2008). If an ambiguous…

It has previously been shown that task performance and frontal cortical activation increase after cognitive conflict. This has been argued to support a model of attention where the level of conflict automatically adjusts the amount of cognitive control applied. Conceivably, conflict could also modulate lower-level processing pathways, which would…

Listeners segment words from the continuous speech stream in their native language by using rhythmic structure, phrasal structure, and phonotactics (e.g. Christophe et al, 2003: McQueen, 1998). One challenging aspect of second language acquisition is the extraction of words from fluent speech, possibly because learners apply a native language…

Recent research provides evidence that individuals shift in their perception of variants depending on social characteristics attributed to the speaker. This paper reports on a speech perception experiment designed to test the degree to which the age attributed to a speaker influences the perception of vowels undergoing a chain shift. As a result…

We report two sets of experiments showing that the large individual variability in language learning success in adults can be attributed to neurophysiological, neuroanatomical, cognitive, and perceptual factors. In the first set of experiments, native English-speaking adults learned to incorporate lexically meaningfully pitch patterns in words. We…

Four experiments investigated the novel issue of learning to accommodate the co-articulated nature of speech. Experiment 1 established a co-articulatory mismatch effect for a set of vowel-consonant (VC) syllables (reaction times were faster for co-articulation matching than for mismatching stimuli). A rhyme judgment training task on words…

It is well established that speakers accommodate in speech production. Recent work has shown a similar effect in perception--speech perception is affected by a listener's beliefs about the speaker. In this paper, we explore the consequences of such perceptual accommodation for experiments in speech perception and lexical access. Our interest is…

Three picture-word interference (PWI) experiments assessed the extent to which embedded subset words are activated during the identification of spoken superset words (e.g., "bone" in "trombone"). Participants named aloud pictures (e.g., "brain") while spoken distractors were presented. In the critical condition,…

The mechanisms underlying the poorer serial recall of talker-variable lists (e.g., alternating female-male voices) as compared with single-voice lists were examined. We tested the novel hypothesis that this "talker variability effect" arises from the tendency for perceptual organization to partition the list into streams based on voice…

Alaryngeal speakers (speakers in whom the larynx has been removed) have inconsistent control over acoustic parameters such as F[subscript 0] and duration. This study investigated whether proficient tracheoesophageal and oesophageal speakers consistently convey phrase boundaries. It was further investigated if these alaryngeal speakers used the…

The effects of lexical context on phonological processing are pervasive and there have been indications that such effects may be modulated by attention. However, attentional modulation in speech processing is neither well documented nor well understood. Experiment 1 demonstrated attentional modulation of lexical facilitation of speech sound…

It has been suggested that infants respond preferentially to infant-directed speech because their auditory sensitivity to sounds with extensive frequency modulation (FM) is better than their sensitivity to less modulated sounds. In this experiment, auditory thresholds for FM tones and for unmodulated, or pure, tones in a background of noise were…

This article reviews experiments completed over the past decade at the National Technical Institute for the Deaf and the State University of New York at Geneseo concerning speech produced during simultaneous communication (SC) and synthesizes the empirical evidence concerning the acoustical and perceptual characteristics of speech in SC.…

The McGurk effect is usually presented as an example of fast, automatic, multisensory integration. We report a series of experiments designed to directly assess these claims. We used a syllabic version of the "speeded classification" paradigm, whereby response latencies to the first (target) syllable of spoken word-like stimuli are slowed down…