A rat model for investigating speech sound recognition in humans: Discrimination learning of synthetic speech sounds dependent on the presence of the auditory cortex

AbstractSpeech is an inherently noisy and ambiguous signal. In order to fluently derive meaning, a listener must integrate contextual information to guide interpretations of the sensory input. While many studies have demonstrated the influence of prior context on speech perception, the neural mechanisms supporting the integration of subsequent context remain unknown. Using magnetoencephalography, we analysed responses to spoken words with a varyingly ambiguous onset phoneme, the identity of which is later disambiguated at the lexical uniqueness point1. Our findings suggest that primmary auditory cortex is sensitive to phonological ambiguity very early during processing — at just 50 ms after onset. Subphonemic detail is preserved in auditory cortex over long timescales, and re-evoked at subsequent phoneme positions. Commitments to phonological categories occur in parallel, resolving on the shorter time-scale of ~450 ms. These findings provide evidence that future input determines the perception of earlier speech sounds by maintaining sensory features until they can be integrated with top down lexical information.Significance statementThe perception of a speech sound is determined by its surrounding context, in the form of words, sentences, and other speech sounds. Often, such contextual information becomes available later than the sensory input. The present study is the first to unveil how the brain uses this subsequent information to aid speech comprehension. Concretely, we find that the auditory system supports prolonged access to the transient acoustic signal, while concurrently making guesses about the identity of the words being said. Such a processing strategy allows the content of the message to be accessed quickly, while also permitting re-analysis of the acoustic signal to minimise parsing mistakes.

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Examination of speech-sounds disorder in children between 78-90 months with reading and writing difficulty

Journal of Human Sciences ◽

10.14687/jhs.v16i3.5687 ◽

2019 ◽

Vol 16 (3) ◽

pp. 770-780

Author(s):

Işık Sibel Küçükünal ◽

Ayşe Dilek Öğretir

Keyword(s):

Data Collection ◽

Recognition Test ◽

Speech Sound ◽

Normal Group ◽

Sound Recognition ◽

Speech Sounds ◽

Writing Difficulties ◽

Reading And Writing ◽

And Control ◽

Experimental Group

In the development of reading and writing, the ability to recognize the speech sounds, which are phonemes, is accepted as the determining factor. Tests are needed to measure auditory processing skills in terms of detecting the nature of the problem in children who have difficulty in reading and writing despite their normal development. For this purpose, it was tried to determine the source of the problem by applying the Speech Sound Recognition Test (SSRT) to the children with and without reading and writing difficulties. By using quantitative research method, 30 children between 78-90 months of age were included in the study. Control 1 (normal) group 10 (6 girls, 4 boys); experimental group (reading and writing difficulty) 10 (6 girls, 4 boys), control 2 (reading and writing difficulty) group were grouped as 10 (5 girls, 5 boys) children. Writing Skills Scale, False Analysis Inventory and Speech Sound Recognition Test were used as data collection tools. In the analysis of data, Kruskal Wallis Variance Analysis was used for descriptive statistics and group comparisons. It was found that the scores of data collection tools, experimental group and control 2 groups were significantly lower than those of the control group. In the experimental and control groups, the mean of starting to talk with the first words of the children having reading and writing difficulty were significantly different when compared to the control 1 group (normal). It was determined that the children in the experimental and control 2 groups started to talk quite late compared to the children in the control 1 (normal) group. According to the present findings, it was seen that delayed speech may have a negative effect on academic skills in the future, and it was concluded that recognition of speech sounds was a basic skill on reading and writing. Children who get phoneme recognition trainings in preschool period can learn to read and write more easily. And also the SSRT can be used as a suitable training material in the detection and education of children with reading and writing difficulties. Extended English summary is in the end of Full Text PDF (TURKISH) file. Özet Okuma yazma gelişiminin sağlanmasında dile ait sesler olan konuşma seslerini tanıma becerisi belirleyici etken olarak kabul görmektedir. Normal gelişim göstermesine rağmen okuma yazma öğreniminde güçlük görülen çocuklarda problemin doğasını tespit etmek açısından, işitsel işlemleme becerisini ölçmeye uygun testlere ihtiyaç duyulmaktadır. Bu amaçla okuma yazma güçlüğü görülen ve görülmeyen çocuklara Konuşma Seslerini Tanıma Testi (KSTT) uygulanarak problemin kaynağı tespit edilmeye çalışılmıştır. Nicel araştırma yöntemi kullanılarak yaşları 78-90 ay aralığında 30 çocuk araştırmaya dahil edilmiştir. Kontrol 1 (normal) grubu 10 (6 kız, 4 erkek); deney (okuma yazma güçlüğü) grubu 10 (6 kız, 4 erkek), kontrol 2 (okuma yazma güçlüğü) grubu 10 (5 kız, 5 erkek) çocuk olarak gruplandırılmıştır. Veri toplama aracı olarak Yazma Becerisi Ölçeği, Yanlış Analizi Envanteri ve Konuşma Seslerini Tanıma Testi kullanılmıştır. Verilerin analizinde tanımlayıcı istatistikler ile grup karşılaştırmalarında Kruskal Wallis Varyans Analizi kullanılmıştır. Okuma yazma güçlüğü olan deney ve kontrol 2 gruplarının, konuşma sesleri tanıma ve tanıdığı sesi yazma puanlarının okuma yazma güçlüğü olmayan kontrol 1 grubuna göre anlamlı düzeyde düşük olduğu görülmüştür. Deney ve kontrol 2 grubundaki çocukların ilk kelimelerini söylemeye başlama ayı ve ikili ifadelere başlama ayı kontrol 1 (normal) grupla karşılaştırıldığında, normallere göre anlamlı düzeyde farklı bulunmuştur. Deney ve kontrol 2 grubundaki çocukların, kontrol 1 (normal) grubundaki çocuklara göre konuşmaya oldukça geç başladığı tespit edilmiştir. Mevcut bulgular doğrultusunda konuşmaya geç başlamanın ilerideki akademik becerileri olumsuz etkileyebileceği görülmüş olup, konuşma seslerini tespit etmenin okuma ve yazma kazanımı üzerinde temel bir beceri olduğu sonucuna varılmıştır. Okul öncesi dönemde konuşma seslerini tanıma eğitimleri ile temel okuma yazma becerisi kazanımının kolaylaştırılması mümkün olacağı gibi, okuma yazma güçlüğü görülen çocukların tespitinde ve eğitiminde KSTT uygun bir eğitim materyali olarak kullanılabilir.

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Speaker-normalized vowel representations in the human auditory cortex

10.1101/397026 ◽

2018 ◽

Author(s):

Matthias J. Sjerps ◽

Neal P. Fox ◽

Keith Johnson ◽

Edward F. Chang

Keyword(s):

Auditory Cortex ◽

Vocal Tract ◽

Contextual Information ◽

Critical Role ◽

Speech Sound ◽

Building Blocks ◽

Speech Sounds ◽

Preceding Context ◽

Speech Cues ◽

Linguistic Units

AbstractHumans identify speech sounds, the fundamental building blocks of spoken language, using the same cues, or acoustic dimensions, as those that differentiate the voices of different speakers. The correct interpretation of speech cues is hence uncertain, and requires normalizing to the specific speaker. Here we assess how the human brain uses speaker-related contextual information to constrain the processing of speech cues. Using high-density electrocorticography, we recorded local neural activity from the cortical surface of participants who were engaged in a speech sound identification task. The speech sounds were preceded by speech from different speakers whose voices differed along the same acoustic dimension that differentiated the target speech sounds (the first formant; the lowest resonance frequency of the vocal tract). We found that the same acoustic speech sound tokens were perceived differently, and evoked different neural responses in auditory cortex, when they were heard in the context of different speakers. Such normalization involved the rescaling of acoustic-phonetic representations of speech, demonstrating a form of recoding before the signal is mapped onto phonemes or higher level linguistic units. This process is the result of auditory cortex’ sensitivity to the contrast between the dominant frequencies in speech sounds and those in their just preceding context. These findings provide important insights into the mechanistic implementation of normalization in human listeners. Moreover, they provide the first direct evidence of speaker-normalized speech sound representations in human parabelt auditory cortex, highlighting its critical role in resolving variability in sensory signals.

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Speech sound discrimination training improves auditory cortex responses in a rat model of autism

Frontiers in Systems Neuroscience ◽

10.3389/fnsys.2014.00137 ◽

2014 ◽

Vol 8 ◽

Cited By ~ 12

Author(s):

Crystal T. Engineer ◽

Tracy M. Centanni ◽

Kwok W. Im ◽

Michael P. Kilgard

Keyword(s):

Auditory Cortex ◽

Discrimination Training ◽

Rat Model ◽

Speech Sound ◽

Sound Discrimination

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Distinctive Phonetic Features as Relevant and Irrelevant Stimulus Dimensions in Speech-Sound Discrimination Learning

Journal of Speech and Hearing Research ◽

10.1044/jshr.1703.417 ◽

1974 ◽

Vol 17 (3) ◽

pp. 417-425

Author(s):

Stuart I. Ritterman ◽

Nancy C. Freeman

Keyword(s):

College Students ◽

Discrimination Learning ◽

Irrelevant Dimension ◽

Speech Sound ◽

Irrelevant Stimulus ◽

Relevant Dimension ◽

Phonetic Features ◽

Sound Discrimination ◽

Nonsense Syllables

Thirty-two college students were required to learn the relevant dimension in each of two randomized lists of auditorily presented stimuli. The stimuli consisted of seven pairs of CV nonsense syllables differing by two relevant dimension units and from zero to seven irrelevant dimension units. Stimulus dimensions were determined according to Saporta’s units of difference. No significant differences in performance as a function of number of the irrelevant dimensions nor characteristics of the relevant dimension were observed.

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Easy Screening for Mild Alzheimer's Disease and Mild Cognitive Impairment from Elderly Speech

Current Alzheimer Research ◽

10.2174/1567205014666171120144343 ◽

2018 ◽

Vol 15 (2) ◽

pp. 104-110 ◽

Cited By ~ 3

Author(s):

Shohei Kato ◽

Akira Homma ◽

Takuto Sakuma

Keyword(s):

Alzheimer’S Disease ◽

Alzheimer's Disease ◽

Cognitive Impairment ◽

Mild Cognitive Impairment ◽

Characteristic Curve ◽

Linear Regression Analysis ◽

Speech Sound ◽

The Elderly ◽

Speech Sounds ◽

Mel Frequency Cepstral Coefficients

Objective: This study presents a novel approach for early detection of cognitive impairment in the elderly. The approach incorporates the use of speech sound analysis, multivariate statistics, and data-mining techniques. We have developed a speech prosody-based cognitive impairment rating (SPCIR) that can distinguish between cognitively normal controls and elderly people with mild Alzheimer's disease (mAD) or mild cognitive impairment (MCI) using prosodic signals extracted from elderly speech while administering a questionnaire. Two hundred and seventy-three Japanese subjects (73 males and 200 females between the ages of 65 and 96) participated in this study. The authors collected speech sounds from segments of dialogue during a revised Hasegawa's dementia scale (HDS-R) examination and talking about topics related to hometown, childhood, and school. The segments correspond to speech sounds from answers to questions regarding birthdate (T1), the name of the subject's elementary school (T2), time orientation (Q2), and repetition of three-digit numbers backward (Q6). As many prosodic features as possible were extracted from each of the speech sounds, including fundamental frequency, formant, and intensity features and mel-frequency cepstral coefficients. They were refined using principal component analysis and/or feature selection. The authors calculated an SPCIR using multiple linear regression analysis. Conclusion: In addition, this study proposes a binary discrimination model of SPCIR using multivariate logistic regression and model selection with receiver operating characteristic curve analysis and reports on the sensitivity and specificity of SPCIR for diagnosis (control vs. MCI/mAD). The study also reports discriminative performances well, thereby suggesting that the proposed approach might be an effective tool for screening the elderly for mAD and MCI.

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