#16. Visual Perception Brain Teaser

QUESTION: Is the inner shape a real circle?

visual circle brain teaser

Some­times extra­ne­ous infor­ma­tion around your tar­get can dis­tort your view. Try cov­er­ing the lines with a piece of card to remove some of the inter­fer­ing information.

Brain func­tions involved:
Here you are exer­cis­ing your visu­al per­cep­tion and deci­sion-mak­ing skills. The visu­al cor­tex in your occip­i­tal lobes process­es visu­al input from your eyes. Not only is the occip­i­tal lobe main­ly respon­si­ble for visu­al recep­tion, it also con­tains asso­ci­a­tion areas that help in the visu­al recog­ni­tion of shapes and col­ors. The prob­lem solv­ing, selec­tive atten­tion, and exec­u­tive func­tions used in this exer­cise are han­dled by the ante­ri­or por­tion of the frontal lobes.

Believe it or not, both shapes are per­fect circles.

Next brain teas­er in Sharp­Brains’ top 25 series:

  • #17. Less obvi­ous than it may appear


  1. Randy on December 17, 2006 at 12:00

    Ok! I final­ly got one. I could see the cir­cle with­in the cir­cle. Then I tried to com­pli­cate it by look­ing for a math­mat­i­cal solution.

  2. Caroline on December 18, 2006 at 2:20

    Glad you got it Randy! I think the moral of that sto­ry is simplify! :)

  3. Mitch on January 4, 2008 at 4:32

    I could see past the lines and see the cir­cle as it would appear on its own — a per­fect circle.

  4. Mark on January 6, 2008 at 8:12


  5. miss on January 11, 2008 at 10:53

    its a per­fect round circle

  6. yahobahne on January 21, 2008 at 6:54

    I see two cir­cles although por­tions of the round­ed lines are bro­ken. I don’t get it.

  7. Alvaro on January 21, 2008 at 7:03

    That’s good: they are 2 full cir­cles. The inte­ri­or one may look like an oval giv­en its posi­tion­ing-this is a visu­al illusion.

  8. yahobahne on January 21, 2008 at 7:20

    Well Alvaro, my visu­al illu­sion only allows me to see the cir­cles. I tried to look for the oval, but could­nt find it. Thxs

  9. gothgirl818 on April 22, 2008 at 6:01

    wow that was well…interesting..

  10. Nevers on May 1, 2008 at 9:56

    if you look at the cen­ter of the out­er cir­cle then you can see that the inner cir­cle is not per­fect. periph­er­als everybody.

  11. Mukesh on June 5, 2008 at 4:20

    yes. inner shape is a circle

  12. bush will on July 28, 2008 at 1:10

    In my per­cep­tion it is not look­ing like cor­rect­ly cir­cle, but like circle.

  13. anthonette on August 5, 2008 at 9:04

    ya.… it looks like a circle

  14. catiana271 on August 15, 2008 at 4:24

    I thought it was a per­fect cir­cle. When I first looked at it, I thought it was­n’t. When they asked me to see if it was, I looked clos­er and saw that it was.

  15. Eclipse1601 on May 2, 2009 at 8:52

    yes; it just appears to not be one b/c of the angle.

About SharpBrains

SHARPBRAINS is an independent think-tank and consulting firm providing services at the frontier of applied neuroscience, health, leadership and innovation.
SHARPBRAINS es un think-tank y consultoría independiente proporcionando servicios para la neurociencia aplicada, salud, liderazgo e innovación.

Top Articles on Brain Health and Neuroplasticity

Top 10 Brain Teasers and Illusions


Subscribe to our e-newsletter

* indicates required

Got the book?