"...psychological phenomenon involving a vague and random stimulus (often an image or sound) being perceived as significant. Common examples include seeing images of animals or faces in clouds, the man in the moon or the Moon rabbit, and hearing hidden messages on records played in reverse..."
Has Sam had this the entire time? From the beginning? Does teleporting ring a bell? Seeing all of those random pictures? Remember Sam's face in the clouds in Ascension?
"The Rorschach inkblot test uses pareidolia in an attempt to gain insight into a person's mental state..."