Speech Physiology, Speech Perception, And Acous... TOP
The auditory thalamus, or medial geniculate body (MGB), is the primary sensory input to auditory cortex. Therefore, it plays a critical role in the complex auditory processing necessary for robust speech perception. This review will describe the functional organization of the thalamus as it relates to processing acoustic features important for speech perception, focusing on thalamic nuclei that relate to auditory representations of language sounds. The MGB can be divided into three main subdivisions, the ventral, dorsal, and medial subdivisions, each with different connectivity, auditory response properties, neuronal properties, and synaptic properties. Together, the MGB subdivisions actively and dynamically shape complex auditory processing and form ongoing communication loops with auditory cortex and subcortical structures.
Speech Physiology, Speech Perception, and Acous...
Previous research suggests that infant speech perception reorganizes in the first year: young infants discriminate both native and non-native phonetic contrasts, but by 10-12 months difficult non-native contrasts are less discriminable whereas performance improves on native contrasts. In the current study, four experiments tested the hypothesis that, in addition to the influence of native language experience, acoustic salience also affects the perceptual reorganization that takes place in infancy. Using a visual habituation paradigm, two nasal place distinctions that differ in relative acoustic salience, acoustically robust labial-alveolar [ma]-[na] and acoustically less salient alveolar-velar [na]-[ enga], were presented to infants in a cross-language design. English-learning infants at 6-8 and 10-12 months showed discrimination of the native and acoustically robust [ma]-[na] (Experiment 1), but not the non-native (in initial position) and acoustically less salient [na]-[ enga] (Experiment 2). Very young (4-5-month-old) English-learning infants tested on the same native and non-native contrasts also showed discrimination of only the [ma]-[na] distinction (Experiment 3). Filipino-learning infants, whose ambient language includes the syllable-initial alveolar (/n/)-velar (/ eng/) contrast, showed discrimination of native [na]-[ enga] at 10-12 months, but not at 6-8 months (Experiment 4). These results support the hypothesis that acoustic salience affects speech perception in infancy, with native language experience facilitating discrimination of an acoustically similar phonetic distinction [na]-[ enga]. We discuss the implications of this developmental profile for a comprehensive theory of speech perception in infancy.
A striking property of speech perception is its resilience in the face of acoustic variability (among speech sounds produced by different speakers at different times, for example). The robustness of speech perception might, in part, result from multiple, complementary representations of the input, which operate in both acoustic-phonetic feature-based and articulatory-gestural domains. Recent studies of the anatomical and functional organization of the non-human primate auditory cortical system point to multiple, parallel, hierarchically organized processing pathways that involve the temporal, parietal and frontal cortices. Functional neuroimaging evidence indicates that a similar organization might underlie speech perception in humans. These parallel, hierarchical processing 'streams', both within and across hemispheres, might operate on distinguishable, complementary types of representations and subserve complementary types of processing. Two long-opposing views of speech perception have posited a basis either in acoustic feature processing or in gestural motor processing; the view put forward here might help reconcile these positions.
Purpose: The ability to hear and understand speech in complex acoustic environments follows a prolonged time course of development. The purpose of this article is to provide a general overview of the literature describing age effects in susceptibility to auditory masking in the context of speech recognition, including a summary of findings related to the maturation of processes thought to facilitate segregation of target from competing speech.
Method: Data from published and ongoing studies are discussed, with a focus on synthesizing results from studies that address age-related changes in the ability to perceive speech in the presence of a small number of competing talkers.
Conclusions: This review provides a summary of the current state of knowledge that is valuable for researchers and clinicians. It highlights the importance of considering listener factors, such as age and hearing status, as well as stimulus factors, such as masker type, when interpreting masked speech recognition data.
When instructed to speak clearly for people with hearing loss, a talker can effectively enhance the intelligibility of his/her speech by producing "clear" speech. We analyzed global acoustic properties of clear and conversational speech from two talkers and measured their speech intelligibility over a wide range of signal-to-noise ratios in acoustic and electric hearing. Consistent with previous studies, we found that clear speech had a slower overall rate, higher temporal amplitude modulations, and also produced higher intelligibility than conversational speech. To delineate the role of temporal amplitude modulations in clear speech, we extracted the temporal envelope from a number of frequency bands and replaced speech fine-structure with noise fine-structure to simulate cochlear implants. Although both simulated and actual cochlear-implant listeners required higher signal-to-noise ratios to achieve normal performance, a 3-4 dB difference in speech reception threshold was preserved between clear and conversational speech for all experimental conditions. These results suggest that while temporal fine structure is important for speech recognition in noise in general, the temporal envelope carries acoustic cues that contribute to the clear speech intelligibility advantage.
1751 COMD Goes to the Movies (3) Introduction to the diverse communication disorders and differences served by the fields of speech-language pathology and audiology through movies, including how reality may differ from stereotypes.
2081 Introduction to Communication Disorders (3) Required initial course for undergraduates concentrating in speech pathology and audiology. Observations in Speech and Hearing Clinic required. Processes involved in speech production; definition, description, and incidence of speech and hearing disorders; overview of the profession, including agencies, related professionals, job opportunities, publications, professional associations, and certification.
4153 Acoustics of Speech and Hearing (4) 3 hrs. lecture; 2 hrs. lab. Also offered as LING 4153. Prereq.: COMD 2050 or equivalent. Production, transmission, and perception of speech acoustics in communication; acoustic phonetics and psycho-acoustics.
4190 Introduction to Audiology (3) Prereq.: COMD 2081 and credit or registration in COMD 4153. Interaction of hearing and speech, effects of hearing loss on speech and language development, types of hearing loss, and evaluation processes.
4380 Speech and Language Development (4) 3 hrs. lecture; 1 hr. lab. Also offered as LING 4380. Language acquisition and behavior, language and cognitive development, verbal learning and structural properties of speech; theories of language development in the normal child.
4590 Auditory Rehabilitation in Children (3) Prereq.: COMD 4153, COMD 4190. Methods of management including modes of communication, auditory and speech-reading training, amplification issues, early identification and intervention, and educational placement.
4683 Clinical Practice: Therapeutic Techniques (1-6 each) Prereq.:Credit in course work related to practicum-specific speech, language or hearing disorder. May be taken for a max. of 8 sem. hrs. of credit each. On- and off-campus practica in speech, language, and hearing disorders.
4684 Clinical Practice: Therapeutic Techniques (1-6 each) Prereq.:Credits in course work related to practicum-specific speech, language or hearing disorder. May be taken for a max. of 8 sem. hrs. of credit each. On- and off-campus practica in speech, language, and hearing disorders.
4685 Clinical Practice: Therapeutic Techniques (1-6 each) Prereq.:Credits in course work related to practicum-specific speech, language, or hearing disorder. May be taken for a max. of 8 sem. hrs. of credit each. On- and off-campus practica in speech, language, and hearing disorders.
4750 Independent Research in Speech Science or Linguistics (1-3) Also offered as LING 4750. May be taken for a max. of 3 hrs. of credit. Readings in speech science or linguistics directed by a senior faculty member.
4753 Undergraduate Seminar in Speech Perception (3) Prereq.: COMD 4190. Not for graduate credit. Introduction to problems in speech perception across the human lifespan, in both typical and atypical listeners.
Advanced study of the communication sciences associated with the process of speech and hearing, including speech perception and production, speech and hearing physiology, and acoustic phonetics. Prerequisite: Admission to the Graduate Certificate in Communication Sciences and Disorders.
The Speech Perception & Acoustics Laboratories (SPA Labs) are a research unit affiliated with the Department of Speech and Hearing Science. The current research program consists of several projects in speech communication which underscore the importance of variation in speech. The variation comes from diverse sources such as speaker characteristics, the geographic region in which the speaker was raised, or from factors related to the dynamic character of broadly defined speech units. The approach taken at the SPA Labs is data-driven and the focus is on constructing large corpora of speech which would provide conclusive answers to the questions asked. The current research addresses several issues in human speech perception, acoustic amplitude variation in coarticulated vowels, dialectal variation in acoustic characteristics of speech, phonetic aspects of sound change, cognitive processing in individuals who stutter, and learning second language phonology. 041b061a72