PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “Speech Perception”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 55 records · Page 3Linked to original sources
PubMed1993

Cerebral specialization for speech perception and movement organization in adults with Down's syndrome.

Adults with Down's syndrome and a group of undifferentiated mentally handicapped persons were examined using a free recall dichotic listening procedure to determine a laterality index for the perception of speech sounds. Subjects also performed both the visual and verbal portions of a standard apraxia battery. As in previous research, subjects with Down's syndrome tended to display a left ear advantage on the dichotic listening test. As well, they performed better on the apraxia battery when movements were cued visually rather than verbally. This verbal-motor disadvantage increased as the left ear dichotic listening advantage became more pronounced. It is argued that the verbal-motor difficulties experienced by persons with Down's syndrome stem from a dissociation of the functional systems responsible for speech perception and movement organization (Elliott and Weeks, 1990).

Aged↗
PubMed2003

The neuroanatomical and functional organization of speech perception.

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.

Acoustic Stimulation↗
PubMed2004

Speech perception.

This chapter focuses on one of the first steps in comprehending spoken language: How do listeners extract the most fundamental linguistic elements-consonants and vowels, or the distinctive features which compose them-from the acoustic signal? We begin by describing three major theoretical perspectives on the perception of speech. Then we review several lines of research that are relevant to distinguishing these perspectives. The research topics surveyed include categorical perception, phonetic context effects, learning of speech and related nonspeech categories, and the relation between speech perception and production. Finally, we describe challenges facing each of the major theoretical perspectives on speech perception.

Humans↗
PubMed2004

The fragile nature of the speech-perception deficit in dyslexia: natural vs synthetic speech.

A number of studies reported that developmental dyslexics are impaired in speech perception, especially for speech signals consisting of rapid auditory transitions. These studies mostly made use of a categorical-perception task with synthetic-speech samples. In this study, we show that deficits in the perception of synthetic speech do not generalise to the perception of more naturally sounding speech, even if the same experimental paradigm is used. This contrasts with the assumption that dyslexics are impaired in the perception of rapid auditory transitions.

Auditory Perceptual Disorders↗
PubMed2000

Towards a functional neuroanatomy of speech perception.

The functional neuroanatomy of speech perception has been difficult to characterize. Part of the difficulty, we suggest, stems from the fact that the neural systems supporting 'speech perception' vary as a function of the task. Specifically, the set of cognitive and neural systems involved in performing traditional laboratory speech perception tasks, such as syllable discrimination or identification, only partially overlap those involved in speech perception as it occurs during natural language comprehension. In this review, we argue that cortical fields in the posterior-superior temporal lobe, bilaterally, constitute the primary substrate for constructing sound-based representations of speech, and that these sound-based representations interface with different supramodal systems in a task-dependent manner. Tasks that require access to the mental lexicon (i.e. accessing meaning-based representations) rely on auditory-to-meaning interface systems in the cortex in the vicinity of the left temporal-parietal-occipital junction. Tasks that require explicit access to speech segments rely on auditory-motor interface systems in the left frontal and parietal lobes. This auditory-motor interface system also appears to be recruited in phonological working memory.

Journal Article↗
PubMed2005

Infants are sensitive to within-category variation in speech perception.

Previous research on speech perception in both adults and infants has supported the view that consonants are perceived categorically; that is, listeners are relatively insensitive to variation below the level of the phoneme. More recent work, on the other hand, has shown adults to be systematically sensitive to within category variation [McMurray, B., Tanenhaus, M., & Aslin, R. (2002). Gradient effects of within-category phonetic variation on lexical access, Cognition, 86 (2), B33-B42.]. Additionally, recent evidence suggests that infants are capable of using within-category variation to segment speech and to learn phonetic categories. Here we report two studies of 8-month-old infants, using the head-turn preference procedure, that examine more directly infants' sensitivity to within-category variation. Infants were exposed to 80 repetitions of words beginning with either /b/ or /p/. After exposure, listening times to tokens of the same category with small variations in VOT were significantly different than to both the originally exposed tokens and to the cross-category-boundary competitors. Thus infants, like adults, show systematic sensitivity to fine-grained, within-category detail in speech perception.

Discrimination Learning↗
PubMed1990

Stimulus variability and processing dependencies in speech perception.

Processing dependencies in speech perception between voice and phoneme were investigated using the Garner (1974) speeded classification procedure. Variability in the voice of the talker and in the cues to word-initial consonants were manipulated. The results showed that the processing of a talker's voice and the perception of voicing are asymmetrically dependent. In addition, when stimulus variability was increased in each dimension, the amount of orthogonal interference obtained for each dimension became significantly larger. The processing asymmetry between voice and phoneme was interpreted in terms of a parallel-contingent relationship of talker normalization processes to auditory-to-phonetic coding processes. The processing of voice information appears to be qualitatively different from the encoding of segmental phonetic information, although they are not independent. Implications of these results for current theories of speech perception are discussed.

Adult↗
PubMed2000

Approach to communication, speech perception and intelligibility after paediatric cochlear implantation.

The aim of this study was to explore the relationship between approach to communication, speech perception and speech intelligibility after cochlear implantation of young children with profound early deafness. A prospective speech perception and speech intelligibility assessment was undertaken on a consecutive group of implanted children. There were 46 children at the three-year, 26 at the four-year and 20 at the five-year intervals. All had been born deaf or deafened before the age of three and received cochlear implants before the age of seven. Their speech perception ability and the intelligibility of their speech were measured before cochlear implantation and annually thereafter. The children's communication had been classified by their teachers of the deaf at each interval into one of two categories: those using an oral approach and those using a signing approach. Results revealed that at all intervals, those children classified as using oral communication significantly exceeded those using signed communication on measures of speech perception and intelligibility (p<0.05). When those children who had changed from signed to oral communication were compared at the three-year interval with those who used oral communication throughout, there was no significant difference in their results. However, it remains to be explored whether children use oral communication after cochlear implantation because they are doing well, or whether they do well because they are using oral communication.

Child↗
PubMed1996

[Comparison of speech perception with cochlear implant and hearing aid--analysis according to speech strategy and hearing level].

This study was carried out to compare the speech perception ability of patients using hearing aids with hearing levels of 81dB or more (55 patients) and those with cochlear implants (67 patients). The patients with hearing aids were divided into group A (hearing levels 81-90dB, 7 patients), group B (91-100dB, 11 patients), group C (101-110dB, 19 patients), group D (111-120dB, 7 patients), and group E (121-130dB, 6 patients). The patients with cochlear implants were using the strategies of F0F1F2 (14 patients), MPEAK (32 patients) and SPEAK (21 patients). Speech perception tests of monosyllables, words, and sentences under conditions of auditory plus vision were administered. The means and standard deviations of percentages giving the correct answer in F0F1F2, MPEAK and SPEAK were 45.2 +/- 14.7%, 45.7 +/- 14.6% and 62.6 +/- 15.9% for monosyllables, 44.8 +/- 18.9%, 56.3 +/- 15.0% and 73.4 +/- 15.5% for words, and 64.0 +/- 26.4%, 60.5 +/- 15.9% and 84.7 +/- 13.8% for sentences. In comparison with the results for patients with hearing aids, and speech perception for F0F1F2 and MPEAK was equivalent to that of group C, and that for SPEAK was better than that of group B but poorer than that of group A. In other words, the speech perception ability in conventional cochlear implant strategies--F0F1F2 and MPEAK--corresponded to that of patients with hearing levels of 101-110dB, but that in the new strategy, SPEAK, gave better results than 91-100dB.

Adolescent↗
PubMed1977

[Paral speech perception (author's transl)].

Speech perception thresholds following surgery for chronic middle ear disease often ar better than the averaged pure tone threshold levels. The author believes that this phenomenon of paradoxical speech perception is due to a central phenomenon.

Auditory Perception↗
PubMed1979

Models and mechanisms in speech perception. Species comparisons provide further contributions.

Results of recent experiments on the perception of speech-sound categories by nonhuman listeners are reviewed in light of current models of speech perception, and are compared to data obtained in similar experiments on human infants. In general, the data on nonhuman animals parallel those obtained from human infants, suggesting the possibility that certain auditory perceptual predispositions shared by mammals played a role in the selection of sounds for a speech-sound repertoire. The findings are generally relevant to the origins and evolution of speech and language, to theories of speech perception, and to the notion of innate predispositions for the perception of auditory signals that are part of an organism's communicative repertoire.

Animals↗
PubMed1985

Speech perception: some new directions in research and theory.

The perception of speech is one of the most fascinating attributes of human behavior; both the auditory periphery and higher centers help define the parameters of sound perception. In this paper some of the fundamental perceptual problems facing speech sciences are described. The paper focuses on several of the new directions speech perception research is taking to solve these problems. Recent developments suggest that major breakthroughs in research and theory will soon be possible. The current study of segmentation, invariance, and normalization are described. The paper summarizes some of the new techniques used to understand auditory perception of speech signals and their linguistic significance to the human listener.

Attention↗
PubMed1989

Speech perception studies using a multichannel electrotactile speech processor, residual hearing, and lipreading.

Three studies are reported on the speech perception of normally hearing and hearing-impaired adults using combinations of visual, auditory, and tactile input. In study 1, mean scores for four normally hearing subjects showed that addition of tactile information, provided through the multichannel electrotactile speech processor, to either audition alone (300-Hz low-pass-filtered speech) or lipreading plus audition resulted in significant improvements in phoneme and word discrimination scores. Information transmission analyses demonstrated the effectiveness of the tactile aid in providing cues to duration, F1 and F2 features for vowels, and manner of articulation features for consonants, especially features requiring detection and discrimination of high-frequency information. In study 2, six different cutoff frequencies were used for a low-pass-filtered auditory signal. Mean scores for vowel and consonant identification were significantly higher with the addition of tactile input to audition alone at each cutoff frequency up to 1500 Hz. The mean speechtracking rate was also significantly increased by the additional tactile input up to 1500 Hz. Study 3 examined speech discrimination of three hearing-impaired adults. Additional information available through the tactile aid was shown to improve speech discrimination scores; however, the degree of increase was inversely related to the level of residual hearing. Results indicate that the electrotactile aid may be useful for patients with little residual hearing and for the severely to profoundly hearing impaired, who could benefit from the high-frequency information presented through the tactile modality, but unavailable through hearing aids.

Adult↗
PubMed1978

Feature detection process in speech perception.

One current view of speech perception is that speech is initially processed by the extraction of independent features which are then integrated over time by a synthesis process into a phonetic or syllabic percept. This feature synthesis model was contrasted with the alternative view that speech is initially processed as a continuous multidimensional whole. Two selective adaptation experiments were carried out to provide a test between these views. In the first experiment, the feature synthesis model predicted an increase in adaptation with an increase in adaptor processing time. The alternative view can also explain this result based on the perceptual simiiarity of the adaptation sequence and the test items. In the second experiment, the alternative view predicted an increase in adaptation with a decrease in adaptor processing time in a case in which the short adaptation sequence was more perceptually similar to the test items than the long sequence. The feature synthesis model cannot readily handle this reversal of the effect found in the first experiment. Some problems with the current view of the feature detection process in speech perception are discussed.

Humans↗
PubMed2006

Speech perception and short-term memory deficits in persistent developmental speech disorder.

Children with developmental speech disorders may have additional deficits in speech perception and/or short-term memory. To determine whether these are only transient developmental delays that can accompany the disorder in childhood or persist as part of the speech disorder, adults with a persistent familial speech disorder were tested on speech perception and short-term memory. Nine adults with a persistent familial developmental speech disorder without language impairment were compared with 20 controls on tasks requiring the discrimination of fine acoustic cues for word identification and on measures of verbal and nonverbal short-term memory. Significant group differences were found in the slopes of the discrimination curves for first formant transitions for word identification with stop gaps of 40 and 20 ms with effect sizes of 1.60 and 1.56. Significant group differences also occurred on tests of nonverbal rhythm and tonal memory, and verbal short-term memory with effect sizes of 2.38, 1.56, and 1.73. No group differences occurred in the use of stop gap durations for word identification. Because frequency-based speech perception and short-term verbal and nonverbal memory deficits both persisted into adulthood in the speech-impaired adults, these deficits may be involved in the persistence of speech disorders without language impairment.

Adolescent↗
PubMed1985

Relations between psychophysical data and speech perception for hearing-impaired subjects. II.

Twenty-one sensorineurally hearing-impaired adolescents were studied with an extensive battery of tone-perception, phoneme-perception, and speech-perception tests. Tests on loudness perception, frequency selectivity, and temporal resolution at the test frequencies of 500, 1000, and 2000 Hz were included. The mean values and the gradient across frequencies were used in further analysis. Phoneme-perception data were gathered by means of similarity judgments and phonemic confusions. Speech-reception thresholds were determined in quiet and in noise for unfiltered speech material, and with additional low-pass and high-pass filtering in noise. The results show that hearing loss for speech is related to both the frequency resolving power and temporal processing by the ear. Phoneme-perception parameters proved to be more related to the filtered-speech thresholds than to the thresholds for unfiltered speech. This finding may indicate that phoneme-perception parameters play only a secondary role, and for that reason their bridging function between tone perception and speech perception is only limited.

Acoustic Stimulation↗
PubMed1989

Analytic study of the Tadoma method: effects of hand position on segmental speech perception.

In the Tadoma method of communication, deaf-blind individuals receive speech by placing a hand on the face and neck of the talker and monitoring actions associated with speech production. Previous research has documented the speech perception, speech production, and linguistic abilities of highly experienced users of the Tadoma method. The current study was performed to gain further insight into the cues involved in the perception of speech segments through Tadoma. Small-set segmental identification experiments were conducted in which the subjects' access to various types of articulatory information was systematically varied by imposing limitations on the contact of the hand with the face. Results obtained on 3 deaf-blind, highly experienced users of Tadoma were examined in terms of percent-correct scores, information transfer, and reception of speech features for each of sixteen experimental conditions. The results were generally consistent with expectations based on the speech cues assumed to be available in the various hand positions.

Adult↗