  Visual fixation is an active process with pupil dynamics as well as
fixational eye movements and microsaccades that support perception. Measures of
both pupil contraction and microsaccades are known to be sensitive to ongoing
cognition and emotional processing. Here we present experimental results from a
visual fixation task demonstrating that pupil size and microsaccade rate
respond differently during self-recognition (when seeing one's own face) than
when seeing familiar or unfamiliar faces. First, the pupil response is
characterized by an immediate pupil-constriction followed by later dilation in
response to stimulus onsets. For one's own face, we observe muted constriction
and greater dilation compared to other faces. Second, microsaccades, which
generally show an inhibitory response to incoming stimuli, are more strongly
inhibited in response to one's own face compared to other faces. Our results
lend support to the idea that eye-related physiological measures could be
useful for authentication or exposing hidden knowledge.
