Tracking of multiple sound sources defined by interaural time differences: brain potential evidence in humans.
Among other cues, interaural time differences (ITD) can be used to compute the location of a sound. To investigate whether ITD can be used for the preattentive detection of sounds coming from a different location than standard sounds (P=0.7, no ITD), left and right 'far' (900 micros ITD, 80 degrees excentricity) and 'near ' (300 micros ITD, 30 degrees ) deviant stimuli (each deviant P=0.075) were presented via headphones. While 15 young healthy subjects passively listened to these sequences, the mismatch negativity (MMN) of the event-related potential was obtained for the deviant sounds. MMN was reliable for all four deviants but larger for the far-lateralized sounds. Moreover, MMN was larger contralateral to the location of the deviant. This indicates a role of preattentive mechanisms in the spatial analysis of auditory scenes.
Nager
Wido
W
Department of Neurology, Medical School Hannover, Hannover, Germany.
Kohlmetz
Christine
C
Joppich
Gregor
G
Möbes
Janine
J
Münte
Thomas F
TF
D000328:Adult; D001921:Brain / Q000502:physiology*; D004569:Electroencephalography; D005072:Evoked Potentials, Auditory; D005260:Female; D006801:Humans; D008297:Male; D013017:Sound Localization; D013997:Time Factors