title: Mismatch negativity elicited by tones and speech sounds: changed topographical distribution in aphasia.
abstract: This study used the event-related brain potential mismatch negativity (MMN) to investigate preconscious discrimination of harmonically rich tones (differing in duration) and consonant-vowel syllables (differing in the initial consonant) in aphasia. Eighteen Norwegian aphasic patients, examined on average 3 months after brain injury, were compared to 11 healthy controls. The main finding was a difference in topographic distribution of the MMN: the aphasia group showed a less lateralized and centralized topographic pattern especially to CV syllables, which is consistent with a reduced temporal lobe processing contribution and an increased right hemisphere activation. No correlations between MMN amplitude and aphasia test results were found.
authors.affiliation: Sunnaas Rehabilitation Hospital, Faculty Division Ullevål University Hospital, University of Oslo, Pb. 1130 Blindern, 0318 Oslo, Norway. frank.becker@sunnaas.no
authors.forename: Frank
authors.initials: F
authors.lastname: Becker
authors.forename: Ivar
authors.initials: I
authors.lastname: Reinvang
mesh_terms: D000161:Acoustic Stimulation; D000293:Adolescent; D000328:Adult; D000368:Aged; D001037:Aphasia / Q000503:physiopathology* / Q000534:rehabilitation; D001288:Attention / Q000502:physiology; D001925:Brain Damage, Chronic / Q000503:physiopathology* / Q000534:rehabilitation; D001931:Brain Mapping; D002540:Cerebral Cortex / Q000503:physiopathology*; D003265:Contingent Negative Variation / Q000502:physiology*; D004292:Dominance, Cerebral / Q000502:physiology; D004569:Electroencephalography; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D009473:Neuronal Plasticity / Q000502:physiology; D009483:Neuropsychological Tests; D010700:Phonetics; D010897:Pitch Discrimination / Q000502:physiology*; D012660:Semantics; D012815:Signal Processing, Computer-Assisted; D013018:Sound Spectrography; D013067:Speech Perception / Q000502:physiology*