Exploritorium - Perception Snacks

The Exploritorium has developed "hands on" activities they call "Snacks". Below is a listing of the Perception Snacks. Click on the individual Snack or go to http://www.exploratorium.edu/snacks/iconperception.html for the listing.

Each snacks provides a detailed description of how to assemble any equipment needed and how to demonstrate the perception concept.

Students could be assigned any number of the snacks to complete on their own and present them to the class or they could do the Snack as an extra credit project. Teachers could use the Snacks to create their own class demonstrations.

Snack Name - Description

• Afterimage - A flash of light prints a lingering image in your eye.
• Anti-Gravity Mirror -It's all done with mirrors!
• Benham's Disk - A rotating black-and-white disk produces the illusion of color.
• Bird in the Cage - Stare at a color and see it change.
• Blind Spot - To see or not to see.
• Bronx Cheer Bulb - Some lightbulbs appear to wiggle and flash when you give them the raspberry, but the only thing wiggling is you.
• Cardboard Tube Syllabus - Your brain combines information from your eyes in surprising ways.
• Cheshire Cat - Make a friend disappear, leaving only a smile behind.
• Colored Shadows - Shadows are not all black and white.
• Depth Spinner -What happens when you get off the merry-go-round?
• Disappearing Act -If you want to stay hidden, you'd better stay still.
• Everyone is You and Me -See yourself become someone else.
• Fading Dot - Now you see it; now you don't. An object without a sharp edge can fade from your view.
• Far 0ut Corners -Your experience of the world influences what you see.
• Gray Step - Without a boundary, it's hard to distinguish different shades of gray.
• Jacques Cousteau in Seashells - There's more to seeing than meets the eye
• Magic Wand - See pictures in thin air.
• Moire Patterns - When you overlap materials with repetitive lines, you create moire patterns.
• Peripheral Vision - We are not usually aware of our eyes' limitations.
• Persistence of Vision - Your eye and brain hold on to a series of images to form a single complete picture.
• Pinhole Magnifier - Who needs expensive optical equipment?
• Proprioception - Even with our eyes closed, we have a sense of body position - where our arms and legs are, for example, and that we are moving them. Muscles, tendons, joints and the inner ear contain proprioceptors, also known as stretch receptors, which relay positional information to our brains.
• Pupil - Your pupil changes size to control how much light enters your eye.
• Real Image - Create the image of an object in space using a $2 ornament.
• Seeing Your Blind Spot - See your blind spot.
• Seeing Your Retina - You can use a dim point of light to cast a shadow of the blood supply of your retina onto the retina itself. This will allow you to see the blood supply of your retina, and even your blind spot.
• Sense of Taste - Receptors on our tongues bind to chemicals in our food and relay the information about the chemicals to our brain. Surprisingly, all those wonderful tastes are transmitted to our brains through only four types of receptors on our tongues - those for sweet, sour, salt and bitter.
• Size and Distance - A clueless way to determine the size of an object.
• Spinning Cyclinder - A spinning rod with a mark near one end is set rotating and spinning at the same time. Amidst the blur of the spinning cylinder, the mark appears three times, forming a stationary triangle.
• Squirming Palm - This visual illusion makes the palm of your hand appear to squirm and twist.
• Thread the Needle - Using two eyes gives you depth perception.
• Vanna - A face seen upside down may hold some surprises.
• Whirling Watcher - When you view short bursts of moving images, you see some interesting effects.