For some time scientists have known that that specialized cells on the tongue are designed to detect five taste categories: bitter, salty, sweet, sour, and umami. Now, thanks to the work of researchers at Columbia University, we know that when taste buds on the tongue detect one of these tastes, they send a message to the brain.
Researchers made the discovery by carefully studying mice who were fed chemicals to trigger salty, sour, umami, bitter, or sweet responses on the tongue. The researchers then monitored each animal’s brain to see how the tastes were interpreted. The tests clearly showed a “hard wired” link between the tongue and brain.
“The cells were beautifully tuned to discrete individual taste qualities, so you have a very nice match between the nature of the cells in your tongue and the quality they represent [in the brain],” noted Dr. Charles Zuker, who contributed to the project.
Zuker and his team hope the discovery will help them create methods for restoring taste sensation, which can be lost as humans age. Many elderly people stop eating — to the detriment of their bodies — because they simply can’t taste their food any longer.
“These findings provide an interesting avenue to help deal with this problem because you have a clear understanding of how taste is functioning so you could imagine ways of enhancing that function,” Zuker said.
