Two separate frontal components in the N1 wave of the human auditory evoked response.
Scalp current density analysis of the auditory evoked response to 1-kHz tone bursts delivered at various interstimulus intervals (ISIs) (from 1 s to 2 min in separate runs) shows that two different frontal components can be observed and functionally dissociated in the N1 time range: one is elicited for all ISIs, peaks at about 95 ms poststimulus, and has a full recovery time below 8 s; the second is elicited only by infrequent stimuli (ISIs > 4 s), peaks around 140 ms, and significantly increases in amplitude with increasing ISIs. The first component can be considered a new obligatory component in N1 elicited simultaneously with the responses in auditory cortex; the later component could correspond to the orienting Component III of Näätänen and Picton (1987).
Brain Signals and Processes Laboratory, INSERM-U280, Lyon, France.
M
M
Alcaini
M H
MH
Giard
M
M
Thévenet
J
J
Pernier
D000161:Acoustic Stimulation; D000293:Adolescent; D000328:Adult; D001143:Arousal / Q000502:physiology*; D001288:Attention / Q000502:physiology*; D001931:Brain Mapping; D005072:Evoked Potentials, Auditory / Q000502:physiology*; D005260:Female; D005625:Frontal Lobe / Q000502:physiology*; D006801:Humans; D008297:Male; D010897:Pitch Discrimination / Q000502:physiology; D012016:Reference Values