Mismatch negativity with visual-only and audiovisual speech.
Brain Topogr
; 21(3-4): 207-15, 2009 May.
Article
en En
| MEDLINE
| ID: mdl-19404730
ABSTRACT
The functional organization of cortical speech processing is thought to be hierarchical, increasing in complexity and proceeding from primary sensory areas centrifugally. The current study used the mismatch negativity (MMN) obtained with electrophysiology (EEG) to investigate the early latency period of visual speech processing under both visual-only (VO) and audiovisual (AV) conditions. Current density reconstruction (CDR) methods were used to model the cortical MMN generator locations. MMNs were obtained with VO and AV speech stimuli at early latencies (approximately 82-87 ms peak in time waveforms relative to the acoustic onset) and in regions of the right lateral temporal and parietal cortices. Latencies were consistent with bottom-up processing of the visible stimuli. We suggest that a visual pathway extracts phonetic cues from visible speech, and that previously reported effects of AV speech in classical early auditory areas, given later reported latencies, could be attributable to modulatory feedback from visual phonetic processing.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Tiempo de Reacción
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Percepción del Habla
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Percepción Visual
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Corteza Cerebral
Tipo de estudio:
Prognostic_studies
Límite:
Adult
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Female
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Humans
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Male
Idioma:
En
Revista:
Brain Topogr
Asunto de la revista:
CEREBRO
Año:
2009
Tipo del documento:
Article
País de afiliación:
Estados Unidos