Taste perception by tongue is possible with the help of taste buds present in the papilla present on surface of tongue, all but filliform papilla contain taste buds. It was first described by Harvard Psychologist D.P Hanig in a German paper (Zur Psychophysik des Geschmackssinnes) about the location of different types of taste perception on tongue. This was the first time someone mentioned that each part of the tongue is useful in tasting only one type of taste.
Note: According to various research papers, it is determined that all the tastes exist on all parts of the tongue equally, some parts of the tongue a little slower to detect certain tastes which lead to this perception.
Nerve supply which help in Taste Perception:
There are two nerves which carry the impulses from taste buds to the brain to help in taste perception – Glossopharyngeal nerve and Chorda Tympani (branch of Facial Nerve. It is mentioned that the Glossopharyngeal nerve supplied to the posterior part of the tongue helps in taste perception to that region while the Chorda Tympani to the front of the tongue.
To determine whether removing or Anesthetising either one of the nerve lead to loss of the particular type of taste was not successful. In 1965, TR Bull a surgeon mentioned that patient who had their Chorda Tympani removed or Cut off did not complain of any taste loss. Linda Bartoshuk from University o Florida mentioned that anesthetizing Chroda Tympani did not affect taste perception in any way. In these two cases Sweet taste should be lost but that was not the case and in both cases patients could experience sweet without any problem.
Number of Taste buds in a Papillae –
Circumvallate papillae, the largest papilla on the tongue have the most number of taste buds in them. Which are located on the posterior border of the tongue in a V-shaped manner.
Taste is perceived with the help of receptor molecules – each type of molecule for one type of taste. All these molecules are present in all locations of the tongue which makes it clear that there is no particular region for the taste to be perceived but all areas can detect all types of tastes.
Taste buds are absent in which papillae –
Filiform papillae are small papillae present on the surface of the tongue and these papillae are not involved in Gustatory (Taste sensation) unlike the other 3 papillae present on the tongue. In between filiform papillae, we can find fungiform papillae
Gustatory or Taste Sensations and their Locations of Tongue and type of papilla involved:
As mentioned above all locations of the tongue are capable of determining all types of tastes. Some areas react faster than the others to certain tastes and hence this location based taste perception theory has been circulated called as “Taste Belt“.
Sweet
- Location: Tip of tongue
- Papilla: Fungiform papillae
- Nerve: Chordatympani
Salt:
- Location: Lateral border of tongue
- Papilla: Fungiform Papilla
- Nerve: Chordatympani Nerve
Sour:
- Location: Lateral border of tongue
- Papilla: Fungiform
- Nerve: Glossopharyngeal nerve
Bitter:
- Location: Posterior part of tongue
- Papilla: Circumvallate papilla
- Nerve: Glossopharyngeal
Many researchers over the years have mentioned based on experiments that taste busds are located all over the mouth – tongue, soft palate and even in throat which help is experiencing taste all over the oral cavity.
Alyssa says
The tongue map has been disproven
Varun says
Can you please share the updated tongue map.
Thanks :)