he current study examined the interaction of fearful, angry,
happy, and neutral expressions with left, straight, and
right eye gaze directions. Human participants viewed
faces consisting of various expression and eye gaze
combinations while event-related potential (ERP) data
were collected. The results showed that angry expressions
modulated the mean amplitude of the P1, whereas fearful
and happy expressions modulated the mean amplitude of
the N170. No influence of eye gaze on mean amplitudes for
the P1 and N170 emerged. Fearful, angry, and happy
expressions began to interact with eye gaze to influence
mean amplitudes in the time window of 200–400 ms.
The results suggest early processing of expression
influence ERPs independent of eye gaze, whereas
expression and gaze interact to influence later
ERPs.