Search results for "Speech discrimination"
showing 8 items of 8 documents
Audiovisual speech perception in children with developmental language disorder in degraded listening conditions.
2013
Purpose The effect of the signal-to-noise ratio (SNR) on the perception of audiovisual speech in children with and without developmental language disorder (DLD) was investigated by varying the noise level and the sound intensity of acoustic speech. The main hypotheses were that the McGurk effect (in which incongruent visual speech alters the auditory speech percept) would be weaker for children with DLD than for controls and that it would get stronger with decreasing SNR in both groups. Method The participants were 8-year-old children with DLD and a sample of children with normal language development. In the McGurk stimuli, the consonant uttered by the voice differed from that articulated …
An extensive pattern of atypical neural speech-sound discrimination in newborns at risk of dyslexia.
2019
Objective: Identifying early signs of developmental dyslexia, associated with deficient speech-sound processing, is paramount to establish early interventions. We aimed to find early speech-sound processing deficiencies in dyslexia, expecting diminished and atypically lateralized event-related potentials (ERP) and mismatch responses (MMR) in newborns at dyslexia risk. Methods: ERPs were recorded to a pseudoword and its variants (vowel-duration, vowel-identity, and syllable-frequency changes) from 88 newborns at high or no familial risk. The response significance was tested, and group, laterality, and frontality effects were assessed with repeated-measures ANOVA. Results: An early positive a…
Children's brain responses to sound changes in pseudo words in a multifeature paradigm.
2011
Abstract Objective The multifeature mismatch negativity (MMN) paradigm has previously been used to study MMN responses to changes in tones or isolated syllables. We tested 4–12year old children's MMNs to changes in a naturally produced pseudo word context. Methods We studied preschoolers' (under the age of 7years, N =15, mean age 5years 4months) and school childrens' (over the age of 7years, N =15, mean age 9years 3months) MMNs to five types of changes (vowel duration, fundamental frequency, gap, intensity, vowel identity) in the middle syllable of a pseudo word [tɑtɑtɑ] using a multifeature paradigm. Results Vowel duration and gap changes elicited larger frontocentral MMN responses than ot…
Spoken-Word Segmentation and Dyslexia
2002
We used magnetoencephalography to elucidate the cortical activation associated with the segmentation of spoken words in nonreading-impaired and dyslexic adults. The subjects listened to binaurally presented sentences where the sentence-ending words were either semantically appropriate or inappropriate to the preceding sentence context. Half of the inappropriate final words shared two or three initial phonemes with the highly expected semantically appropriate words. Two temporally and functionally distinct response patterns were detected in the superior temporal lobe. The first response peaked at approximately 100 msec in the supratemporal plane and showed no sensitivity to the semantic appr…
Auditory Event-Related Potentials in the Study of Developmental Language-Related Disorders
1997
This article reviews recent auditory event-related potential (ERP) studies of developmental language disorder (DLD) and dyslexia/reading disorder (RD). The possibility of using ERPs in searching for precursors of these disorders in the early development of infants at risk is also discussed. Differences in exogenous/sensory ERPs at the latency range of P1 and N1-P2 components have been reported between groups with DLD and RD and control groups. Latency differences between the groups may be related to a common timing deficit suggested by some researchers to be one of the possible underlying factors both in DLD and dyslexia. N1 amplitude group differences may be partly related to arousal/atten…
The mid-difference hump in forward-masked intensity discrimination
2008
Forward-masked intensity-difference limens (DLs) for pure-tone standards presented at low, medium, and high levels were obtained for a wide range of masker-standard level differences. At a standard level of 25 dB SPL, the masker had a significant effect on intensity resolution, and the data showed a mid-difference hump: The DL elevation was greater at intermediate than at large masker-standard level differences. These results support the hypothesis that the effect of a forward masker on intensity resolution is modulated by the similarity between the masker and the standard. For a given masker-standard level difference, the effect of the masker on the DL was larger for a 55-dB SPL than for t…
Detrimental noise effects on brain's speech functions.
2009
Background noise has become part of our everyday life in modern societies. Its presence affects both the ability to concentrate and communicate. Some individuals, like children, the elderly, and non-native speakers have pronounced problems in noisy environments. Here we review evidence suggesting that background noise has both transient and Sustained detrimental effects on central speech processing. Studies on the effects of noise on neural processes have demonstrated hemispheric reorganization in speech processing in adult individuals during background noise. During noise, the well-known left hemisphere dominance in speech discrimination became right hemisphere preponderant. Furthermore, l…
Auditory discrimination profiles of speech sound changes in 6-year-old children as determined with the multi-feature MMN paradigm.
2009
Objective: A linguistic multi-feature mismatch negativity (MMN) paradigm with five types of changes (vowel, vowel-duration, consonant, frequency (F0), and intensity) in Finnish syllables was used to determine speech-sound discrimination in 17 normally-developing 6-year-old children. The MMNs for vowel and vowel-duration were also recorded in an oddball condition in order to compare the two paradigms. Similar MMNs in the two paradigms would suggest that they tap the same processes. This would promote the usefulness of the more time-efficient multi-feature paradigm for future studies in children. Methods: MMNs to five deviant types were recorded in the multi-feature paradigm in which these de…