TOUCHING.....

THE TOUCH DETECTOR

The body organ used for touching is the SKIN. Every bit of skin all over our bodies, including our nails, is used for touching. The nerve endings in the skin send signals to the brain, the brain analyzes the signals and registers the effect of the touch, then signals the reaction to the rest of the body. Some sections of the skin are more sensitive than others. To demonstrate this take an object with an irregular surface (a Ping-Pong paddle works well) and touch it to the elbow, the knee, .... anywhere but the hand, and try to identify the surface characteristics. Finally touch the paddle to the fingertips. The fingertips win "hands down" in the high sensitivity touching contest!

Make your own touch surfaces by coating index cards with glue, then spreading on separate cards items such as popcorn, sugar, flour, seeds, sand, paper, soil, etc.
Put each card in a separate, numbered paper bag and have each student reach into each bag and identify each surface.
Younger students can be helped by having a duplicate reference set of cards available to compare, older students are on their own!
(This is also a good time to get some "expert" help by asking students for suggestions as to surfaces you could add to the activity next time!)

MYSTERY FABRICS

This time put in each numbered bags a sample from a variety of fabric items such as: a towel, a sock, a tee-shirt, denim or corduroy jeans, a sack, a lace curtain, something suede, something furry, and so on. The rules are the same as the Surface Quiz above.

CHARTING AND RECORD KEEPING

Chart some different touch sensations, determine their opposites and select common items and chart their touch characteristics.

WHERE AM I?

Here's a touching story.
It is a warm day, I can really feel the heat on my face when I turn it up to the sky. As I walk along the soles of my bare feet are feeling something hard, hot and ridged. I turn and go down steps which feel the same, I hold onto the rail which also feels hot, hard and ridged against my palm. At the bottom of the steps my feet land on a soft surface which gives way with each step I take. After walking for a few minutes the ground feels hard and soon my feet are wet, air is gently blowing on all of my body. With each step my legs are getting wetter. I stop walking when I feel my knees getting wet. I turn around, see a friend in the distance and walk towards her. My foot comes down on something squishy and slimy in the water - Yuck! I run back to the beginning, up the steps and don't stop until my feet feel that hard ridged surface again. Where have I been?

INVENTIONS

Scientists are researching and investigating the sense of touch with very interesting results. They have invented artificial hands to work robotically in places where human hands cannot work; places such as deep space or tiny spaces, places where there are dangerous conditions or materials, places where the robot hand can be remotely controlled. To make such robots the inventors must examine exactly how our hand and brain work together when we use our sense of touch, and then copy it into a machine.
Imagine the scientist who must invent a robot hand to take the cap off a bottle of dangerous liquid.
First she must carefully watch a person do it, paying attention to each step ....
How slowly our fingertips reach the cap (so as not to tip it over),
How hard we grasp the cap (too tight will crack the bottle, too loose it slips),
How gently we turn the cap until it is loose,
and finally how gently we lift the cap off.
There are a lot of scientific actions involved in opening a bottle!

Look at A GRASPING ROBOT to see how an actual robotic hand operates.

More information will be found with the following links to:
EXPLORE THE BRAIN.
A TEMPERATURE ILLUSION.
AMAZING ANIMAL SENSES.

For an entertaining book about touch and the other senses, read:
"What Can It Be? Riddles About the Senses" by Jacqueline Ball.