Is the face-sensitive N170 the only ERP not affected by selective attention?
We assessed the effect of directed attention on early neurophysiological indices of face processing, measuring the N170 event-related potential (ERP). Twelve subjects were tested on two tasks each in which they attended either to eyes only or to faces with eyes closed, presented within series of facial and control stimuli. Consistent with the ERP literature, N170 was recorded to facial stimuli at posterior temporal electrodes and a concomitant positive peak at the vertex, with latencies around 150 ms for faces and 174 ms for eyes. However, unlike fMRI studies, neither the latency nor the amplitude of the peaks were sensitive to the target/non-target status of either the eyes or the face stimuli. This suggests that early stages of face processing indexed by N 170 are automatic and unmodified by selective attention.
Centre de Recherche Cerveau et Cognition, UMR CNRS/UPS 5549, Université Paul Sabatier, Toulouse, France.
A S
AS
Cauquil
G E
GE
Edmonds
M J
MJ
Taylor
D000328:Adult; D001288:Attention / Q000502:physiology*; D005071:Evoked Potentials / Q000502:physiology*; D005123:Eye; D005145:Face; D005260:Female; D006801:Humans; D008297:Male; D011930:Reaction Time; D014796:Visual Perception / Q000502:physiology*