Search results for "speech perception"
showing 10 items of 136 documents
Speech perception outcomes after cochlear implantation in prelingually deaf infants: The Western Sicily experience
2013
Objectives: To describe audiometric characteristics and speech perception performances of prelingually deaf Sicilian children after cochlear implantation; to identify the influence of cochlear implant (CI) user and family's characteristics on speech recognition and intelligibility outcomes. Methods: Twenty-eight infants with a congenital or acquired hearing impairment and implanted before the 3rd year of life were studied; all children suffered from bilateral sensorineural hearing loss (SNHL) with evidence of lack of hearing aids benefit and no evidence of intellectual disability. The study of the main characteristics associated with CI user and family's profile was performed with a clinica…
Disentangling effects of auditory distraction and of stimulus-response sequence
2009
When we pay attention to one task, irrelevant changes may interfere. The effect of changes on behavioral and electrophysiological responses has been studied in two separate research fields: Research on Distraction states that a rare irrelevant change takes attention away from the primary task. Research on Sequences states that any change in stimulus or response incurs a cost or benefit depending on the kind of change. To disentangle distraction from sequence effects, we made task-irrelevant changes rare in one condition and frequent in another while also assessing stimulus and response changes from trial to trial. Participants used key presses to classify syllables presented in two differen…
Electrophysiology Reveals the Neural Dynamics of Naturalistic Auditory Language Processing: Event-Related Potentials Reflect Continuous Model Updates.
2016
The recent trend away from ANOVA-based analyses places experimental investigations into the neurobiology of cognition in more naturalistic and ecologically valid designs within reach. Using mixed-effects models for epoch-based regression, we demonstrate the feasibility of examining event-related potentials (ERPs), and in particular the N400, to study the neural dynamics of human auditory language processing in a naturalistic setting. Despite the large variability between trials during naturalistic stimulation, we replicated previous findings from the literature: the effects of frequency, animacy, word order and find previously unexplored interaction effects. This suggests a new perspective …
Brain responses to changes in speech sound durations differ between infants with and without familial risk for dyslexia
2002
A specific learning disability, developmental dyslexia, is a language-based disorder that is shown to be strongly familial. Therefore, infants born to families with a history of the disorder are at an elevated risk for the disorder. However, little is known of the potential early markers of dyslexia. Here we report differences between 6-month-old infants with and without high risk of familial dyslexia in brain electrical activation generated by changes in the temporal structure of speech sounds, a critical cueing feature in speech. We measured event-related brain responses to consonant duration changes embedded in ata pseudowords applying an oddball paradigm, in which pseudoword tokens with…
Event-Related Potentials and Consonant Differentiation in Newborns with Familial Risk for Dyslexia
2004
We measured event-related potentials (ERPs) to synthetic consonant-vowel syllables (/ba/, /da/, /ga/) from 26 newborns with familial risk for dyslexia and 23 control infants participating in the Jyväskylä Longitudinal Study of Dyslexia. The syllables were presented with equal probability and with interstimulus intervals ranging from 3,010 to 7,285 ms. Analyses of averaged ERPs from the latencies identified on the basis of principal component analysis (PCA) revealed significant group differences in stop-consonant processing in several latency ranges. At the latencies of 50-170 ms and 540-630 ms, the responses to /ga/ were larger and more positive than those to /ba/ and /da/ in the right hem…
Processing of word stress related acoustic information : A multi-feature MMN study
2016
In the present study, we investigated the processing of word stress related acoustic features in a word context. In a passive oddball multi-feature MMN experiment, we presented a disyllabic pseudo-word with two acoustically similar syllables as standard stimulus, and five contrasting deviants that differed from the standard in that they were either stressed on the first syllable or contained a vowel change. Stress was realized by an increase of f0, intensity, vowel duration or consonant duration. The vowel change was used to investigate if phonemic and prosodic changes elicit different MMN components. As a control condition, we presented non-speech counterparts of the speech stimuli. Result…
Lexical and conceptual components of stem completion priming in patients with Alzheimer's disease
1999
This study evaluated the hypothesis of dissociation between normal lexical but deficient conceptual repetition priming in patients with Alzheimer's disease (AD). For this purpose, we administered to patients with AD and age-matched normal controls the Stem Completion task. In Experiment 1, the level of word processing during study was manipulated by requiring subjects to count vowels (graphemic condition) or generate meanings (semantic condition) of target words. In Experiment 2, the presentation modality was varied during the study to obtain an intramodal and crossmodal repetition priming. Probably due to a floor effect of performance in the graphemic condition, in Experiment 1, AD patient…
Assessment of Three-and-a-Half-Year-Old Children's Emerging Phonological Awareness in a Computer Animation Context
2003
Four computer-animated tasks were created to analyze the underlying structure of emerging phonological awareness at 3.5 years of age and to explore the factors that influence children's ( N = 91) performance on the tasks. Our findings indicated that already at this young age, children are able to master tasks demanding identification, blending, and continuation of phonological units when the tasks are presented in a motivating assessment context. In line with earlier research, children showed higher mastery in dealing with words and syllables than in dealing with phonemes. Targets in the initial position of a word were easier for children to identify than those in the final position. Our an…
Perception of phonemic length and its relation to reading and spelling skills in children with family risk for dyslexia in the first three grades of …
2010
Purpose To examine the ability to discriminate phonemic length and the association of this ability with reading accuracy, reading speed, and spelling accuracy in Finnish children throughout Grades 1–3. Method Reading-disabled (RDFR, n = 35) and typically reading children (TRFR, n = 69) with family risk for dyslexia and typically reading control children (TRC, n = 80) were tested once in each grade of Grades 1–3 using a phonemic length discrimination task. Reading, spelling, IQ, verbal short-term memory, phonological memory, and naming speed were assessed. Results The RDFR group made more errors in phonemic length discrimination than the TRC group in Grades 2 and 3. After taking into accoun…
The Selective Impairment of Phonological Processing in Speech Production
2000
We report the naming performance of a patient (DM) with a fluent progressive aphasia who made phonological errors in all language production tasks. The pattern of errors in naming was strikingly clear: DM made very many phonological errors that resulted almost always in nonword responses. The complete absence of semantic errors and the very low ratio of formal errors relative to nonword errors (1.6:30.3) in DM's performance are discussed in the context of recent claims about the nature of naming deficits in fluent aphasics. We argue that DM's performance makes highly improbable the claim that fluent aphasia results from global lesions affecting all levels of the lexical access system equall…