Mike May cannot readily distinguish between the first (normal) face and the second face, in which the eyes and mouth have been inverted. The reason is one of the great mysteries explained by his story.
Note that when the images are flipped upside down, the second faces become more normal looking to us. That’s also part of the mystery.
I borrowed this image from Robert Kurson’s website. It illustrates how Mike May interprets the world. This is a fascinating phenomena called Prosopagnosia or “face blindness.” 60 Minutes did an incredible story on this condition. I’ll try to post the video later this week.