Despite our beliefs, a team of biochemistry, molecular biophysics and neuroscience scientists at Columbia University Medical Center (USA) has discovered that despite the taste receptors located on the tongue, it is our brain that who really recognizes flavors ; that is, the sense of taste is found in the brain and not in the tongue.
“ Taste, as we all understand it, is ultimately in the brain. The taste receptors on the tongue detect sweetness or bitterness, but it is the brain that provides meaning to these chemicals, ”explains Charles S. Zuker, leader of the study.
The researchers proved this hypothesis by manipulating brain cells in a group of laboratory mice that allowed them to change the way the mice tasted a certain substance. Thus, taking into account that it is a single set of cells in the brain that are responsible for detecting all tastes , the researchers used optogenetics to deliberately turn specific neurons on or off with a laser.
The result was that by silencing the neurons associated with the sweet taste, the rodents were unable to identify the sweet taste, but still detected the bitter one . By performing the opposite experiment, silencing the neurons for the bitter taste, the mice could not recognize this taste but could recognize the sweet one. Furthermore, this hypothesis was also confirmed even by simply administering tap water . The rodents felt nausea or behaviors associated with sweet (increasing their intake) simply by turning on or off the neurons corresponding to these two main flavors.
” These experiments formally demonstrate that the sense of taste is completely hardwired , regardless of learning or experience,” concludes Zuker.
The study has been published in the journal Nature .
