Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “PHONETICS”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

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

At least 919 records · Page 51Linked to original sources
PubMed1996

Role of articulation in speech perception: clues from production.

The relative roles played by signal properties and nonsignal information in speech perception are first examined. The evidence strongly suggests that phonetic percepts are never knowledge-innocent records of the raw signal. That conclusion is drawn not only about "higher" levels of language processing, but is seen to apply also to the perception of elementary phonetic stimuli. A review of a broad range of facts about production highlights the fact that speech production is adaptively organized. That circumstance suggests that the signal does not encode articulatory or acoustic/auditory invariants, but plays the role of supplementing the multimodal information already in place in the listener's speech processing system. It is accordingly proposed that phonetic signals are not invariants wrapped in "noise," but are products of listener-dependent adaptations that transform speech patterns in principled and, therefore, interpretable ways. Do listeners form speech percepts by way of intermediate articulatory representations? There seem to be strong both theoretical and methodological reasons to doubt that they do.

Humans↗
PubMed2000

Speech perception in children with cochlear implants: effects of lexical difficulty, talker variability, and word length.

The present results demonstrated that all 3 factors --lexical difficulty, stimulus variability, and word length--significantly influenced spoken word recognition by children with multichannel cochlear implants. Lexically easy words were recognized significantly better than lexically hard words, regardless of talker condition or word length of the stimuli. These results support the earlier findings of Kirk et al(12) obtained with live-voice stimulus presentation and suggest that lexical effects are very robust. Despite the fact that listeners with cochlear implants receive a degraded speech signal, it appears that they organize and access words from memory relationally in the context of other words. The present results concerning talker variability contradict those previously reported in the literature for listeners with normal hearing(7,11) and for listeners with mild-to-moderate hearing loss who use hearing aids.(14) The previous investigators used talkers and word lists different from those used in the current study and found that word recognition declined as talker variability increased. In the current study, word recognition was better in the multiple-talker condition than in the single-talker condition. Kirk(15) reported similar results for postlingually deafened adults with cochlear implants who were tested on the recorded word lists used in the present study. Although the talkers were equally intelligible to listeners with normal hearing in the pilot study, they were not equally intelligible to children or adults with cochlear implants. It appears that either the man in the single-talker condition was particularly difficult to understand or that some of the talkers in the multiple-talker condition were particularly easy to understand. Despite the unexpected direction of the talker effects, the present results demonstrate that children with cochlear implants are sensitive to differences among talkers and that talker characteristics influence their spoken word recognition. We are conducting a study to assess the intelligibility of each of the 6 talkers to listeners with cochlear implants. Such studies should aid the development of equivalent testing conditions for listeners with cochlear implants. There are 2 possible reasons the children in the present study identified multisyllabic words better than monosyllabic words. First, they may use the linguistic redundancy cues in multisyllabic words to aid in spoken word recognition. Second, multisyllabic words come from relatively sparse lexical neighborhoods compared with monosyllabic tokens. That is, multisyllabic words have fewer phonetically similar words, or neighbors, competing for selection than do monosyllabic stimuli. These lexical characteristics most likely contribute to the differences in identification noted as a function of word length. The significant lexical and word length effects noted here may yield important diagnostic information about spoken word recognition by children with sensory aids. For example, children who can make relatively fine phonetic distinctions should demonstrate only small differences in the recognition of lexically easy versus hard words or of monosyllabic versus multisyllabic stimuli. In contrast, children who process speech using broad phonetic categories should show much larger differences. That is, they may not be able to accurately encode words in general or lexically hard words specifically. Further study is warranted to determine the interaction between spoken word recognition and individual word encoding strategies.

Child, Preschool↗
PubMed2005

Use of visual information in speech perception: evidence for a visual rate effect both with and without a McGurk effect.

The McGurk effect, where an incongruent visual syllable influences identification of an auditory syllable, does not always occur, suggesting that perceivers sometimes fail to use relevant visual phonetic information. We tested whether another visual phonetic effect, which involves the influence of visual speaking rate on perceived voicing (Green & Miller, 1985), would occur in instances when the McGurk effect does not. In Experiment 1, we established this visual rate effect using auditory and visual stimuli matching in place of articulation, finding a shift in the voicing boundary along an auditory voice-onset-time continuum with fast versus slow visual speech tokens. In Experiment 2, we used auditory and visual stimuli differing in place of articulation and found a shift in the voicing boundary due to visual rate when the McGurk effect occurred and, more critically, when it did not. The latter finding indicates that phonetically relevant visual information is used in speech perception even when the McGurk effect does not occur, suggesting that the incidence of the McGurk effect underestimates the extent of audio-visual integration.

Adolescent↗
PubMed1995

Evidence for a central representation of instrument timbre.

An information processing account of perception seeks to delineate the stages of processing through which a stimulus passes and determine the properties of the representation at each stage. Research in phonetic perception has identified two stages, the second of which is thought to encode abstract acoustic attributes of sounds. The present study provided a further test of this proposal by assessing whether nonphonetic stimuli could yield results similar to those obtained with phonetic stimuli. Five selective adaptation experiments were carried out with a trumpet-piano timbre continuum. Two manipulations were used to measure abstract encoding: cross-ear presentation of adaptor and test series, and the use of adaptors that were acoustically different from the continuum end-points. The results provide evidence for an abstract representation of timbre. The similarity of the findings to those in the phonetic adaptation literature is discussed.

Adult↗
PubMed2003

[Speech therapy intervention in phonological disorders from the psycholinguistic paradigm of speech processing].

The aim of this study is to present a survey of speech therapy intervention in phonological disorders (PD). We will examine the concepts of normal phonological development and those involved in PD in order to understand how they have been dealt with, historically, in speech therapy intervention. Lastly, we will describe how evaluation and intervention are carried out from the speech processing paradigm. Phonetic phonological skills allow people to decode the phonic strings they hear so as to be able to gain access to their phonological form and meaning. These abilities also enable them to encode these strings from lexical representations to pronounce words. The greater part of their development takes place during approximately the first four years of life. Speech processing difficulties affect the phonetic phonological skills and occur throughout almost all language pathologies, although the effect they exert is not always the same. This can range from a lack of the capacity to speak to important problems of intelligibility or mild problems with certain phonemes. Their influence on learning to read and write has been shown in recent decades. Speech therapy intervention began from a model based on articulatory phonetics. In the 70s a linguistic model based on the process of speech simplification and phonological analysis was added and this gave rise to a marked improvement in the systems used for evaluation and intervention. At present we have assumed a psycholinguistic model that links the perceptive skills with productive ones and top-down or bottom-up processing (from lexical representations to perception or production of phonemes and vice-versa).

Articulation Disorders↗
PubMedDate not supplied

[Assessment of frontal functions in psychiatric patients during maintenance electroconvulsive therapy].

INTRODUCTION: Previous studies on adverse cognitive effects of electroconvulsive therapy (ECT) have not found any significant alteration of the frontal functions after an acute treatment course. This study aims to assess frontal executive functions in psychiatric patients during maintenance electroconvulsive therapy (M-ECT). SUBJECTS AND METHODS: Thirty two patients treated with M-ECT and 29 psychiatric patients never treated with ECT were evaluated with neuropsychological tests that assessed the following frontal functions: work memory, planning, cognitive flexibility, attention, visuomotor velocity, verbal abstract reasoning and phonetic verbal fluency. RESULTS: Multivariate global analysis did not detect significant frontal function tests differences between both groups. The M-ECT group only scored significantly lower on the FAS test, a test that measures phonetic verbal fluency. A significant correlation between number of previous ECT sessions and performance in the FAS was found. CONCLUSIONS: The M-ECT patient group presented a phonetic verbal fluency alteration that may also be associated to the previous number of ECT sessions. No significant differences in the other frontal functions were detected.

Bipolar Disorder↗
PubMed2005

Decision analysis for the assessment of a record linkage procedure: application to a perinatal network.

OBJECTIVES: According to European legislation, we must develop computer software allowing the linkage of medical records previously rendered anonymous. Some of them, like AUTOMATCH, are used in daily practice either to gather medical files in epidemiologic studies or for clinical purpose. In the first situation, the aim is to avoid homonymous errors, and in the second one, synonymous errors. The objective of this work is to study the effect of different parameters (number of identification variables, phonetic treatments of names, direct or probabilistic linkage procedure) on the reliability of the linkage in order to determine which strategy is the best according to the purpose of the linkage. METHODS: The assessment of the Burgundy Perinatal Network requires the linking of discharge abstracts of mothers and neonates, collected in all the hospitals of the region. Those data are used to compare direct and probabilistic linkage, using different parameterization strategies. RESULTS: If the linkage has to be performed in real time, so that no validation of indecisions generated by probabilistic linkage is possible, probabilistic linkage using three variables without any phonetic treatment seems to be the most appropriate approach, combined with a direct linkage using four variables applied to non-conclusive links. If a validation of indecisions is possible in an epidemiological study, probabilistic linkage using five variables, with a phonetic treatment adapted to the local language has to be preferred. For medical purpose, it should be combined with a direct linkage with four or five variables. CONCLUSION: This paper reveals that the time and money available to manage indecision as well as the purpose of the linkage are of paramount importance for choosing a linkage strategy.

France↗
PubMed1992

[Investigation of "reading" with FFT analysis of the beta waves in EEG during "rapid-reading"].

The beta waves in electroencephalograms (EEGs) during "reading" were investigated by means of the Fast Fourier Transform (FFT) analysis method. The subjects who had mastered a "rapid-reading" method, were classified into two groups according to their rapid-reading achievement level: the "under-trained readers" (male 5, female 2) had already acquired the ability of smooth eye movement, but continued to use the mental phonetic process while reading. The "well-trained readers" (male 6, female 2) could understand the contents of the text without resorting to such phonetic process. All subjects were righthanded. The tasks were designed to eliminate the artifact of the eye movement and the electromyogram as much as possible. The EEGs were recorded with twelve channels of the international standard 10-20 electrode system. The relative power value (R.P.V.) was calculated as follows: RPV(%) = [(X-C)/N] x 100(%) where X is the beta 1 or beta 2 power value by FFT analysis while doing tasks, C is the power value while doing control tasks, and N is the value in the resting state with the eyes open. The results were statistically analyzed by paired t-test. The following results were obtained: In both groups; (a) the left angular gyrus was usually activate during the rapid-reading; (b) the Wernicke's center was activated only during reading with the phonetic process; (c) in the well-trained readers the activation of the right visual cortex was associated with some visual imaging during the rapid-reading; (d) in the under-trained readers, the association between the activation of the central frontal area and the rapid-reading was observed. Thus, the following model for "reading" was obtained: Two parallel pathways seem important in the processing of the verbal information presented visually; one relates only to the left angular gyrus where the visual-verbal information is processed directly, and the other relates to the interactive pathway between the left angular gyrus and the Wernicke's center. Moreover, the visual cortex of the non-verbal hemisphere seems to play some role in understanding verbal information.

Beta Rhythm↗
PubMed1997

Anterior crowns in re-establishing vertical dimension of occlusion: overcoming fear of heights.

The rejuvenation of this dentition is initiated with the placement of six anterior crowns. Re-establishing the vertical dimension has allowed the restoration of pleasing proportions to the centrals. This has led to the re-assertion of the dominance of the centrals and thus corrected the reverse smile line. The restoration of these teeth demands harmonious accommodation of the requirements of esthetics, phonetics and function. These considerations are inseparable and are in fact, determinants of each other. Esthetics and phonetics help determine the degree of vertical opening and incisal edge placement. This location influences anterior guidance, lingual and labial contours, the pitch of the anterior teeth and proper lip support. The principles of proportion, so important in esthetics, allow us, to calculate incisor length. Thus, function, phonetics and esthetics are intimately intertwined and enhance one another in the restoration of vertical dimension of occlusion.

Bruxism↗
PubMed2004

Bimodal speech perception in infant hearing aid and cochlear implant users.

OBJECTIVES: To determine the feasibility of replicating prior bimodal perception findings with hearing-impaired infants during their preimplant, hearing aid trial, and postimplant experiences; secondarily, to determine the point in development at which these infants were able to match phonetic information in the lips and voice for the vowels /a/ and /i/. METHODS: A total of 10 infants with hearing loss, aged 4 to 24 months, were assessed at least once prior to cochlear implantation and previous to implant stimulation. The Split-Screen Preferential Looking Procedure was used to evaluate the bimodal perception skills of these infants. RESULTS: Examples of individual bimodal perception data and preliminary group data are presented. A difference in performance across preimplant and postimplant test sessions was noted for the individuals and the group. CONCLUSION: These data provide evidence that the infants' audibility levels were improved by their cochlear implants, which may have contributed to their evolving ability to match phonetic information in the lips and voice.

Cochlear Implants↗
PubMed1996

The foreign accent syndrome: a reconsideration.

This study compared the post-CVA speech of a patient presenting with the foreign accent syndrome (FAS) to both a premorbid baseline for that patient and to similarly analyzed data from an earlier reported case of FAS. The object of this research was to provide quantitative acoustic data to determine whether: (1) the constellation of phonetic features associated with FAS is the same across patients and (2) a common neural mechanism underlies FAS. Acoustic parameters investigated included features of consonant production (voicing, place and manner of articulation), vowel production (formant frequency and duration), and prosody. Results supported the characterization of FAS patients as having a "generic" foreign accent and the hypothesis that FAS deficits are qualitatively different from that of Broca's aphasia. However, comparison of this case with recent studies revealed the extent to which the constellation of phonetic features may vary among FAS patients, challenging the notion that a general prosodic disturbance is the sole underlying mechanism in FAS.

Brain↗
PubMed1997

Hemispheric asymmetries in reading Korean: task matters.

Native Korean readers were studied in a visual half-field paradigm. Subjects were to make speeded judgments on Hangul (syllabic) and Hanzza (logographic) scripts based on phonetic or visual properties of the stimuli. A task by visual field interaction was obtained indicating that, for both scripts, responses on the phonetic task were faster in the right visual field, whereas no visual field differences were found on the visual task. Script type did not interact with visual field. The results support a task-based account of hemispheric differences in verbal processing.

Adult↗
PubMed2001

Parametrically dissociating speech and nonspeech perception in the brain using fMRI.

Candidate brain regions constituting a neural network for preattentive phonetic perception were identified with fMRI and multivariate multiple regression of imaging data. Stimuli contrasted along speech/nonspeech, acoustic, or phonetic complexity (three levels each) and natural/synthetic dimensions. Seven distributed brain regions' activity correlated with speech and speech complexity dimensions, including five left-sided foci [posterior superior temporal gyrus (STG), angular gyrus, ventral occipitotemporal cortex, inferior/posterior supramarginal gyrus, and middle frontal gyrus (MFG)] and two right-sided foci (posterior STG and anterior insula). Only the left MFG discriminated natural and synthetic speech. The data also supported a parallel rather than serial model of auditory speech and nonspeech perception.

Adult↗
PubMed2001

Mapping from sound to meaning: reduced lexical activation in Broca's aphasics.

Recent studies of lexical access in Broca's aphasics suggest that lexical activation levels are reduced in these patients. The present study compared the performance of Broca's aphasics with that of normal subjects in an auditory semantic priming paradigm. Lexical decision times were measured in response to word targets preceded by an intact semantically related prime word ("cat"-"dog"), by a related prime in which one segment was acoustically altered to produce a poorer phonetic exemplar ("c*at"-"dog"), and by a semantically unrelated prime ("ring"-"dog"). The effects of the locus of the acoustic distortion within the prime word (initial or final position) and the presence of potential lexical competitors ("cat" --> /gaet/versus "coat" --> "goat") were examined. In normal subjects, the acoustic manipulations produce a small, short-lived reduction in semantic facilitation irrespective of the position of the distortion in the prime word or the presence of a voiced lexical competitor. In contrast, Broca's aphasics showed a large and lasting reduction in priming in response to word-initial acoustic distortions, but only a weak effect of word-final distortions on priming. In both phonetic positions, the effect of distortion was greater for prime words with a lexical competitor. These findings are compatible with the claim that Broca's aphasics have reduced lexical activation levels, which may result in a disruption of the bottom-up access of words on the basis of acoustic input as well as increased vulnerability to competition between acoustically similar lexical items.

Adult↗
PubMed2002

Early parallel processing of auditory word and voice information.

The present study investigates the relationship of linguistic (phonetic) and extralinguistic (voice) information in preattentive auditory processing. We provide neurophysiological data, which show for the first time that both kinds of information are processed in parallel at an early preattentive stage. In order to establish the temporal and spatial organization of the underlying neuronal processes, we studied the conjunction of voice and word deviations in a mismatch negativity experiment, whereby the listener's brain responses were collected using magnetoencephalography. The stimuli consisted of single spoken words, whereby the deviants manifested a change of the word, of the voice, or both word and voice simultaneously (combined). First, we identified the N100m (overlain by mismatch field, MMF) and localized its generators, analyzing N100 m/MMF latency, dipole localization, and dipole strength. While the responses evoked by deviant stimuli were more anterior than the standard, localization differences between the deviants could not be shown. The dipole strength was larger for deviants than the standard stimulus, but again, no differences between the deviants could be established. There was no difference in the hemispheric lateralization of the responses. However, a difference between the deviants was observed in the latencies. The N100 m/MMF revealed a significantly shorter and less variant latency for the combined stimulus compared to all other experimental conditions. The data suggest an integral parallel processing model, which describes the early extraction of phonetic and voice information from the speech signal as parallel and contingent processes.

Adult↗
PubMedDate not supplied

How is linguistic memory accessed? A psychophysiological approach.

The role of "subvocalization" during language comprehension, especially reading, is examined. Four arguments against it having a role in accessing memory are erroneous because 1) its latency is much shorter than is conventionally stated; 2) rate of visual information processing is erroneously estimated by failing to distinguish between reading and scanning; 3) covert speech does not disappear in the competent language performer; and 4) the argument that subvocalization is an epiphenomenon is irrelevant. Rather, data support the generalization that covert speech is present during all cognitive functioning and that its specific topography is discriminatively related to the class of phoneme being processed. It is thus inferred that during cognition the speech musculature generates a phonetic code that may function to access linguistic memory. However, since there are also numerous other psychophysiologic events associated with covert speech, a multichannel processing system is hypothesized wherein speech, visual, and kinesthetic modalities interact with the brain. Illustrations are given of how this accessing model is compatible with existing holographic and feature analyzer models of memory. Data are presented that illustrate how phonetically encoded neuromuscular events can be directly measured through psychophysiologic methods. It is hypothesized that cognitive processes are generated when cybernetic neuromuscular circuits selectively interact. Consequently, all components of these neuromuscular circuits serve a function during cognition so that a role for "subvocalization" (a muscular component) cannot be ruled out in an apriori manner.

Electromyography↗
PubMed2005

Acoustic aspects of the formation of speech in children in the third year of life.

This study covers the third year of life as part of a longitudinal investigation of the establishment of speech in Russian children performed on the basis of listener, phonetic, and instrumented acoustical analysis. The present report addresses the establishment of those additional acoustic and phonetic characteristics in children's speech which allow speech recognition. This is the first instrumented analysis in Russian children with statistical assessment of the dynamics of vowel formants in children's words, of the establishment of characteristics (stress, lack of stress), opposition (palatalization, lack of palatalization of consonants), and voice onset time for plosive consonants. The results showed that recognition of children's words by listeners with a high probability of success resulted from the formation of a system of acoustically stable properties in the children's speech which together provide informational adequacy for verbal communication.

Adult↗
PubMed1990

Short-term memory coding by deaf signers: the primary language coding hypothesis reconsidered.

Shand (Cognitive Psychology, 1982, 14, 1-12) hypothesized that strong reliance on a phonetic code by hearing individuals in short-term memory situations reflects their primary language experience. As support for this proposal, Shand reported an experiment in which deaf signers' recall of lists of printed English words was poorer when the American Sign Language translations of those words were structurally similar than when they were structurally unrelated. He interpreted this result as evidence that the deaf subjects were recoding the printed words into sign, reflecting their primary language experience. This primary language interpretation is challenged in the present article first by an experiment in which a group of hearing subjects showed a similar recall pattern on Shand's lists of words, and second by a review of the literature on short-term memory studies with deaf subjects. The literature survey reveals that whether or not deaf signers recode into sign depends on a variety of task and subject factors, and that, contrary to the primary language hypothesis, deaf signers may recode into a phonetic code in short-term recall.

Adult↗