TED-Ed: How optical illusions trick your brain - Nathan S. Jacobs

The video explores optical illusions using examples like grids, muffin pans, and Abraham Lincoln's photo. It explains how our brain interprets visual information, often leading to illusions. The grid illusion is due to lateral inhibition, while lighting assumptions affect our perception of the muffin pan. The upside-down Lincoln face highlights how our brain uses shortcuts in facial recognition. These illusions reveal how our brain constructs a 3D world using visual cues and assumptions.

What happens to the white spots in your peripheral vision when you focus on the center of the grid?

• They remain white.

• They show flashes of grey.

• They turn completely black.

• They disappear entirely.

How do retinal ganglion cells contribute to the perception of optical illusions?

• By changing colors.

• By increasing brightness.

• By enhancing contrast through lateral inhibition.

• By blurring the image.

What is the main reason optical illusions can trick us even with glasses on?

• They are only visible on screens.

• They are too small to see clearly.

• They exploit the brain's interpretation of visual information.

• They rely on color changes.

What assumption does the brain make about lighting when interpreting the muffin pan illusion?

• Light is evenly distributed.

• Light comes from below.

• Light comes from the side.

• Light comes from a single source above.

Why does the upside-down Lincoln face appear normal at first?

• The image is blurred.

• The lighting is incorrect.

• The entire face is upside down.

• The eyes and mouth are right side up.

Which part of the brain is primarily involved in recognizing faces?

• The parietal lobe.

• The fusiform face area.

• The cerebellum.

• The frontal lobe.

How does the brain efficiently process visual information?

• By ignoring all details.

• By using assumptions to create a simplified vision of the world.

• By focusing only on colors.

• By analyzing each pixel individually.