tongue mapping: fact or fiction?

What you'll need
cotton buds
salt water
sugar water
lemon juice
tonic water
paper to draw your map on
one coloured pen/pencil for each taste

The tongue mapping theory
Tongue mapping first came about when a German paper was translated incorrectly into American by a psychologist called Edwin Boring, and was misunderstood. The theory suggests that specific areas of the tongue are associated with sensing specific tastes:

1 = bitter, 2 = sour, 3 = salty, 4 = sweet

How to test the tongue mapping theory
1. Take a clean cotton bud and dip it in the sugar water.

2. Touch it onto the tip of your tongue and see if you can taste it. Then try some different areas of your tongue.

3. Use a coloured pen or pencil to draw where you can taste the sweet taste on your tongue map.

4. Swill your mouth out with water to get rid of the sweet taste. Repeat this process with the other solutions: salt water, lemon juice and tonic water.

5. Compare your tongue map to other people's maps and see where they are similar and different. Then compare it to the map above.

Debunking the theory
Tongue mapping is a myth. The theory is not supported by scientific evidence, as you should have discovered (and as we discovered at science group today). The whole tongue is covered in tiny bumps called papillae, or taste buds. Inside the papillae are a variety of receptors which are sensitive to a whole range of different tastes. So, the whole tongue is responsible for tasting everything, all of the time. Sometimes though, some areas of the tongue are more sensitive to a particular taste due to there being more of that kind of receptor in that particular area.