I was involved in some great research looking at the difference between how artists and non artists look at images. Eye trackers heavily used.
Outcome: artists are more likely to track away from obvious points of interest. So in the case of a portrait, the artist might be looking at a brick by the subject's feet, whilst everyone else's gaze would be fixed on the subject's eyes.
Outcome: artists are more likely to track away from obvious points of interest. So in the case of a portrait, the artist might be looking at a brick by the subject's feet, whilst everyone else's gaze would be fixed on the subject's eyes.