Motion information available to different sensory modalities can interact at both perceptual and post-perceptual (i.e., decisional) stages of processing. However, to date, researchers have only been able to demonstrate the influence of one of these components at any given time, hence the relationship between them remains uncertain. We addressed…

This study examined the perception of the four Mandarin lexical tones by Mandarin-naive Hong Kong Cantonese, Japanese, and Canadian English listener groups. Their performance on an identification task, following a brief familiarization task, was analyzed in terms of tonal sensitivities (A-prime scores on correct identifications) and tonal errors…

Listeners can explicitly categorize unfamiliar talkers by regional dialect with above-chance performance under ideal listening conditions. However, the extent to which this important source of variation affects speech processing is largely unknown. In a series of four experiments, we examined the effects of dialect variation on speech…

Previous research has shown that English infants are sensitive to mispronunciations of vowels in familiar words by as early as 15-months of age. These results suggest that not only are infants sensitive to large mispronunciations of the vowels in words, but also sensitive to smaller mispronunciations, involving changes to only one dimension of the…

Background: The non-word repetition task (NRT) has gained wide acceptance in describing language acquisition in both children with normal language development (NL) and children with specific language impairments (SLI). This task has gained wide acceptance because it so closely matches the phonological component of word learning, and correlates…

Participants listened to the Asian disease problem framed in terms of either gains or losses and chose between two plans to combat the disease. All participants heard the problem embedded in other sounds; for some it was the relatively lower-frequency information, and for others it was the relatively higher-frequency information. The classic…

Four experiments examined transfer of noncorresponding spatial stimulus-response associations to an auditory Simon task for which stimulus location was irrelevant. Experiment 1 established that, for a horizontal auditory Simon task, transfer of spatial associations occurs after 300 trials of practice with an incompatible mapping of auditory …

To what extent does language acquisition recruit domain-general processing mechanisms? In this dissertation, evidence concerning this question is garnered from the study of individual differences in infant speech perception and their predictive value with respect to language development in early childhood. In the first experiment, variation in the…

Poor readers perform worse than their normal reading peers on a variety of speech perception tasks, which may be linked to their phonological processing abilities. The purpose of the study was to compare the brain activation patterns of normal and impaired readers on speech perception to better understand the phonological basis in reading…

Several recent experiments indicate that, when learning words, children are not as sensitive to phonemic differences (e.g., /d/ vs. /t/) as they are in discrimination tasks [Pater, J., Stager, C. L., & Werker, J. F. (2004). "The perceptual acquisition of phonological contrasts." "Language," 80, 384-402; Stager, C. L., & Werker, J. F. (1997).…

Purpose: To examine perceptual deficits as a potential underlying cause of specific language impairments (SLI). Method: Twenty-one children with SLI (8;7-11;11 [years;months]) and 21 age-matched controls participated in categorical perception tasks using four series of syllables for which perceived syllable-initial voicing varied. Series were…

This study investigated whether task instructions affect sound-isolation performance. The effects of phoneme class and phoneme position were also assessed. Two hundred Dutch kindergartners were presented with a free-sound-isolation task and its constrained counterparts: an initial-, a middle-, and a final-sound-isolation task. All tasks contained…

Objective: Time reproduction is deficient in children with attention-deficit/hyperactivity disorder (ADHD). Whether this deficit is familial and could therefore serve as a candidate endophenotype has not been previously investigated. It is unknown whether timing deficits are also measurable in adolescent children with ADHD and nonaffected…

Recent neuroimaging studies and neuropsychological data suggest that there are regions in posterior auditory cortex that participate both in speech perception and speech production. An outstanding question is whether the same neural regions support both perception and production or whether there exist discrete cortical fields subserving these…

In three experiments, participants listened for a target's pitch change within recurrent nine-tone patterns having largely isochronous rhythms. Patterns differed in pitch structure of initial (context) and final (target distance) pattern segments. Also varied were: probe timing (Experiments 2 and 3) and instructions about probe timing (Experiments…