Science project

Now You See It, Now You Don't: How Age and Sex Affect Our Ability to Perceive Optical Illusions

Materials and Equipment / Ingredients

  • 10 printouts of optical illusions, which can be obtained here, here, or here
  • At least 10 test subjects for each gender and age group (children six and older, teens, adults, and the elderly)
  • A timer/watch/clock
  • Pen and paper

Research Questions:

  • What are physiological illusions and cognitive illusions?
  • Why are some people capable of seeing certain optical illusions that other cannot?
  • How does the brain work hand-in-hand with the eye?
  • Does the size of the brain matter in terms of intelligence and being able to see optical illusions?

Optical Illusions are basically images concealed by other images. Your eyes and your brain work together to play these "tricks" on you in the form of colors, size, multiple images, object placement, etc. For example, perhaps you have seen "vibrating" text that seems to wiggle in their place with no tangible explanation. That is an optical illusion. There are four sub-categorized forms of cognitive illusions: ambiguous, distorting, paradox, and fictional. In this experiment, we'll try to discover if females or males tend to do better on optical illusion tests and whether certain age groups also do better. Remember, not everyone can see everything in an optical illusion, that is what makes them so interesting to look at.


Duck-Rabbit Illusion

Experimental Procedure:

  1. Print out some optical illusions from the web or obtain them from books before you begin experimenting. You should know the illusions to these already.
  2. Find at least 10 people of each gender and 10 people in each age group (children six and up, teens, adults, and the elderly.)
  3. Test each test subject separately. Show them each of the optical illusions you have chosen and ask them what they see. Record their responses and use the chart provided below to record data.
  4. Repeat the previous step for all your test subjects.
  5. At the conclusion of testing, evaluate your responses and see which gender and age did the best or the worst and everything in between. Does gender and age really play a role?

Test subject #: _______ Gender:____________ Age: __________ Group:___________


Illusion #

Able To See Illusion? Which ones?
























Terms and Concepts: Ambiguous illusions, Paradox illusions, distorting illusions, fictional illusions, optical illusions, physiological illusions,afterimages, impossible objects, splenium, the human brain, sight  


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