Frontal gamma-band activity in magnetoencephalogram during auditory oddball processing.
Previous studies have demonstrated induced gamma-band activity (GBA) over posterior temporo-parietal and inferior frontal cortex during auditory spatial vs pattern mismatch processing, respectively. Here we investigated magnetoencephalographic oscillatory responses during an active auditory pattern oddball task. Fourteen subjects were instructed to detect pairs of deviating animal vocalizations in a sequence of standard sounds. The comparison of targets with standards revealed differences in oscillatory activity >80 Hz 200-300 ms after stimulus onset. GBA was increased over left inferior frontal cortex, replicating previous results of putative auditory ventral stream activation during passive pattern deviance processing. Additional GBA enhancements over superior frontal cortex were specific to active target detection. They probably reflected executive networks involved in memory maintenance and decision making.
Kaiser
Jochen
J
MEG-Center, Institute of Medical Psychology and Behavioral Neurobiology, University of Tübingen, Gartenstrasse 29, 72074 Tübingen, Germany. jochen.kaiser@uni-tubingen.de
Lutzenberger
Werner
W
D000161:Acoustic Stimulation / Q000379:methods*; D000328:Adult; D005072:Evoked Potentials, Auditory / Q000502:physiology*; D005260:Female; D005625:Frontal Lobe / Q000502:physiology*; D006801:Humans; D015225:Magnetoencephalography / Q000379:methods*; D008297:Male