November 10, 2007

Distance changes face perception?

illusion, perception, social psychology — thomasr @ 4:14 am Print This Post  AddThis Social Bookmark Button

Illusion%20image.jpgThis is  probably one of the best illusions ever! Please do the following: look at the above images from your seat in front of the computer; Mr. Angry is on the left, and Ms.Calm is on the right. Now, get up from your seat, and move back 10 or 12 feet. Who’s the angry and calm now?


It’s said that this illusion was made by Phillippe G.Schyns and Aude Oliva. Cudos to Robert Karl Stonjek for showing us this illusion.


  1. This striking illusion helps us understand the role of the neuronal brain mechanism for size constancy in visual perception. I don’t know what the creators of the illusion would say, but this is how it seems to me. The two images are each composed of two facial expressions, namely *calm* and *angry*. However, in the face on the left the angry features are composed of high spatial-frequency components, and the calm features are composed of low spatial-frequency components. For the face on the right, calm is expressed
    by high spatial-frequency features and angry is low frequency. If we view the two faces from a distance of 1 foot, the high-frequency features dominate so the left face is angry while the right face is calm. If we view the faces from a distance of 10 feet, the low-frequency features dominate so the left face is calm while the right face is angry. This all happens because the size-constancy mechanism in the visual system expands the brain’s representation of the faces to compensate as their retinal size contracts tenfold when we move back from a 1-foot view to a 10-foot view.
    As this happens, visual resolution is degraded with the increase in viewing distance, and the low-frequency features become dominant. Hence the switch in facial expression. For a detailed neuronal model of the brain’s putative size-constancy mechanism see *The Cognitive Brain*, pp. 89-93. If there is another explanation for this illusion, I would very much like to see it.

    Arnold Trehub

    Comment by Arnold Trehub — November 10, 2007 @ 2:41 pm

  2. The images are from:
    Schyns, P.G., Oliva, A. (1999). Dr. Angry and Mr. Smile: When categorization flexibly modifies the perception of faces in rapid visual presentations. Cognition 69(3):243–265. [doi: 10.1016/S0010-0277(98)00069-9] [PMID: 10193048]

    Comment by Eric — November 14, 2007 @ 4:30 pm

  3. this is an amazing illusion. not only do the two appear to switch positions the gender switches sides too. just imagine the layers required to create this illusion. thank you.

    Comment by sharon — November 17, 2007 @ 10:46 am

  4. i got the same effect by blurring my vision, didn’t have to get up! :)

    Comment by sk — November 18, 2007 @ 12:25 pm

  5. Thanks for the explanation, Arnold. The post is pointless without it.

    Comment by jqb — November 26, 2007 @ 10:52 pm

  6. jqp, this is exactly the idea with SCR. As this is a non-profit and free-labour initiative, we cannot do much else than point people to the relevant sources of new information. Arnold so brilliantly offers the details, thus making the post more valuable. SCR relies on the effort of all. We need your contributions!


    Comment by thomasr — December 7, 2007 @ 6:11 am

RSS feed for comments on this post. TrackBack URI

Leave a comment

Line and paragraph breaks automatic, e-mail address never displayed, HTML allowed: <a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <strike> <strong>