Can you toe the line?

A cream and orange exhibit table stands in front of orange knee high padded fences that re sitting on brown-grey carpet.

When the brain receives mismatching sensory signals, it needs to work harder for simple tasks such as walking.

How it works

Hold a special pair of prism glasses up to your eyes and try to walk around looping patterns on the ground. When you look through the prism glasses, your view of the world becomes skewed, as does your sense of balance.

Things to try or ask around the exhibit

  • Is one track easier to follow than the other.
  • What would happen if you wore these glasses for 24 hours straight?
  • Some people feel disoriented, while others don’t feel any effect at all when they walk along while using these prism glasses. How do you feel?


Standing and walking is a complex business, so adding these prism glasses to the equation may seem a bit unfair (but it’s fun)!

Usually, your brain relies heavily on visual signals to know how your body is positioned in space. The prism glasses force you to only see your feet and the floor. In other words, they remove visual cues about your vertical world. Because your vision is compromised (compared to what you’re used to seeing), your brain defers to your inner ear’s vestibular system.

Vestibular fluid inside your ears (which helps you stay balanced) signals to your brain that your head is upright. However, your brain is getting visual input about the floor below you instead of what’s ahead or in front of you. The vestibular cues conflict with the visual cues of your feet and the floor, so some people become disoriented.

Finding the science in your world

The glasses used in this exhibit are 'bed goggles' which are used by patients who are incapacitated in bed, so they can read, watch television, or see people without lifting their head.