'Tongue taste maps' have been a classic experiment for primary school aged children for many years. Many text books will
incorrectly reveal that there are indeed areas of taste on your tongue, i.e. some areas taste salt better than sugar etc. The problem is that this has been based on faulty science!
There are no specific areas on your tongue exclusively for salt, sugar or sour tastes.
Your sense of taste comes from small structures called taste buds, collectively called 'papillae'. These papillae occur on top of the tongue, epiglottis and soft palate within your mouth. There are five taste sensations: sweet, sour, bitter, savory and salty. Your food's taste comes from a mixture of signals being sent to the brain from the papillae within your mouth.
The popular belief that there are specific taste areas over the tongue comes from a poorly translated german psychological study conducted in 1901! Sensitivity to all tastes is apparent throughout the tongue, with stronger sensations being produced in different areas due to differing numbers of papillae on the tongue.
Check this Wikipedia external link for further information.
