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Experiment No. 8

One Point or Two!

Experiment: To show that the back of your hand has fewer nerves than your finger tips.

Materials:

You will need:

One or two compasses (two sharp pencils will do)
A partner

 

Method:

1) Blindfold your partner.Prick your partners hand with the compass or compasses (or pencils - as in the picture) at different times while he or she looks away.

2) Prick your partners hand with either one or both compasses. Move the points quite close together and then further apart, when using both. Ask, each time, if one or two points are being felt.

3) Try the same on the tips of your partner's fingers.

Result: What happened?
When pricked on the back of the hand, quite often your partner will only feel one point - even though you have used both! Things are different on the tips of your partner's finger. They will generally feel both points.

Conclusion: The back of the hand has less nerve receptors than the tips of the fingers. It is more important to have nerves here as we use our fingers for touch. Therefore they are packed much closer together.

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