title: Temporal integration of deviant sound in automatic detection reflected by mismatch negativity.
abstract: Mismatch negativity (MMN) is an event-related potential that is elicited by deviant sounds that are presented along with frequent sounds in the absence of attention. Auditory MMN is generated by the comparison process between sensory memory trace of a frequent auditory event and a deviant event. It is well known that frequent sounds are encoded in memory trace and processed as a single unit within 160-170 ms. This study examined whether deviant sound would be similarly processed as a temporal unit. Twelve healthy men were presented with relatively short standard sounds and relatively long deviant sounds that contained an omitted (i.e. silent) part. Three types of deviant sounds were designed to vary in duration. The MMN amplitude was gradually enhanced from the short to long duration deviant events that contained an omitted part. In contrast, MMN latency showed no significant differences among the deviants. These findings show that deviant sounds are also processed as a unitary event.
authors.affiliation: Department of Neuropsychiatry, Fukushima Medical University, Fukushima, Japan. tetsuya3@fmu.ac.jp
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Shiga
authors.forename: Hirooki
authors.initials: H
authors.lastname: Yabe
authors.forename: Le
authors.initials: L
authors.lastname: Yu
authors.forename: Michinari
authors.initials: M
authors.lastname: Nozaki
authors.forename: Syuntaro
authors.initials: S
authors.lastname: Itagaki
authors.forename: Tsuo-Hung
authors.initials: TH
authors.lastname: Lan
authors.forename: Shin-ichi
authors.initials: S
authors.lastname: Niwa
mesh_terms: D000161:Acoustic Stimulation / Q000379:methods; D000328:Adult; D001307:Auditory Perception / Q000502:physiology*; D001921:Brain / Q000502:physiology; D005071:Evoked Potentials / Q000502:physiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011930:Reaction Time / Q000502:physiology*; D013998:Time Perception / Q000502:physiology*; D014473:Unconscious, Psychology; D055815:Young Adult