Context modulates processing of speech sounds in the right auditory cortex of human subjects

• Published in: Neuroscience letters Vol. 331; no. 2; pp. 91 - 94
• Main Authors: Kujala, Anu, Alho, Kimmo, Valle, Saija, Sivonen, Päivi, Ilmoniemi, Risto J., Alku, Paavo, Näätänen, Risto
• Format: Journal Article
• Language: English
• Published: Shannon Elsevier Ireland Ltd 11-10-2002; Elsevier
• Subjects: Acoustic Stimulation; Adult; Auditory Cortex - physiology; Biological and medical sciences; Context; Ear and associated structures. Auditory pathways and centers. Hearing. Vocal organ. Phonation. Sound production. Echolocation; Evoked Potentials, Auditory - physiology; Female; Functional Laterality - physiology; Fundamental and applied biological sciences. Psychology; Humans; Lateralization; Magnetic counterpart of mismatch negativity; Magnetoencephalography; Male; Speech perception; Speech Perception - physiology; Vertebrates: nervous system and sense organs; Context; Magnetic counterpart of mismatch negativity; Magnetoencephalography; Speech perception; Lateralization; Human; Central nervous system; Information processing; Speech; Perception; Auditory pathway; Auditory cortex; Brain (vertebrata)
• ISSN: 0304-3940; 1872-7972
• DOI: 10.1016/S0304-3940(02)00843-1

Using whole-head magnetoencephalography, we studied how context affects processing of speech sounds by recording the magnetic counterpart (MMNm) of the mismatch negativity (MMN) event-related potential, which is elicited in the auditory cortex by a contrast between infrequent and frequent auditory stimuli. In Experiment 1, in the right, but not in the left, hemisphere auditory cortex, a contrast of consonant–vowel syllables elicited a stronger MMNm when presented within a word context than when occurring alone. Further, in Experiment 2, these same syllable contrasts were processed in the right auditory cortex more strongly when embedded in a non-speech sound context than when presented alone. This facilitation thus was insensitive to the phonetic and semantic features of the context but might nevertheless reflect the participation of the right hemisphere in speech perception.