In this post we will talk about the taste center in the brain, we will study how the sense of taste works and how the brain intervenes in this process of sensory information.
Taste center in brain
The taste center of the brain is located in the temporal cortex, it is the one that really recognizes flavors. The sense of taste is in the brain and not in the tongue.
When we take a sip of coffee, its taste first impacts the taste buds of the tongue, palate or esophagus and produces a reaction that travels immediately through the neurons of the facial nerves until it reaches the brain that it perceives as acceptable or rejectionable in the event that it disgusted us.
Our sense of taste also activates other brain areas that allow us to remember that taste of coffee, because we have tried it before, and we can even recognize different nuances in the same flavor and compare with others that we have stored in our memory.
And the brain enables us to go further; Before a steaming cup of coffee we can anticipate and imagine how it will taste and even have the sensation of already tasting it.
A whole brain mechanism that starts up with several actions at the same time: The first time we taste something, that taste hits the taste buds, is sent to the brain and reaches the sensory reception centers that are in the postcentral zone of the parietal lobe
But part of that information is also going to be distributed in the areas of the brain that will select if it is a pleasant taste or not, something that the brain amygdala, which is located in the temporal lobe, is in charge of. Also in this lobe is the limbic system, which houses the memory capable of reminding us if we have tried that flavor before.
There are people who when they drink chocolate it can produce such a complex reaction that it even de-stresses them. And this happens because areas such as the brain’s reward center are activated and it gives them a sense of satisfaction “like a prize.”
The sense of taste is in the brain and not in the tongue
The world is an illusion created by the brain, since at no time can we come into contact with reality if it is not through the interpretations made by the nervous system.
Some of these sensations seem to be more fixed and to be programmed in the genes or in the body’s organization (for example, the sensors that warn that the skin is burned are always activated when it passes a certain temperature), while others seem be more flexible and change as the brain learns (for example, only with time does the taste of wine begin to be appreciated).
In relation to the sense of taste, it is often thought that the taste buds are responsible for detecting the five flavors of food and sending that information to the brain.
But now, a group of researchers from Columbia University Medical Center, has published an article in the journal “Nature” in which they show that a mouse can be caused to perceive that water is sweet or bitter just by modifying a group of neurons in the body.
“The most important thing about this study is the discovery that it is possible to ‘recreate’ an animal’s taste perception and the internal representation of sweet and sour tastes, by directly manipulating the brain,” explained Charles S. Zuker, director of the study and investigator of the Howard Hughes Medical Institute.
That is why, in his opinion, “the taste, as we know it, is ultimately in the brain, not in the tongue.”
This, put another way, means that the tongue may have receptors to pick up bitter and sweet taste, but it is in the brain that those signals make sense.
Flavor map in the brain
In the last decade, Zuker’s team has proven that each group of taste receptors on the tongue sends a specific signal to the brain, and that there is a group of neurons that are dedicated exclusively to each flavor and that are found in different areas of the cerebral cortex. In fact, it has even been possible to map flavors in the brain.
But now, a further step has been taken: “In this study, we wanted to see if there are specific regions in the brain that activate the sensation of bitter and sweet.
If there are, silencing these regions would prevent the animal from perceiving those sensations, even though we gave it sweet or sour stimuli (on the tongue), ”Zucker explained.
For this reason, “if we activate these areas, they should perceive a sweet or sour taste even if they are drinking water.”
Water that tastes sweet or sour
And this is exactly what the researchers have found. When the scientists injected a substance to silence neurons for the sweet taste, the mice stopped perceiving this taste, but continued to perceive the bitterness. The same happened changing the roles.
Even if they were given water and those areas were activated, the animals tasted what the researchers wanted.
To do this, they resorted to optogenetics, a technique that allows the brain of experimental animals to be modified so that specific neurons respond to the light of a laser and can be activated or deactivated at will.
In addition, they observed if the animals sucked more in search of supposedly sweet water, or if on the contrary they appeared nausea and rejection of the bitter.
Taste programmed in humans
Even among animals that had never had any of these tastes before, they observed these responses by turning specific neurons on and off.
For this reason, for Zuker, “these experiments formally prove that the sense of taste is totally programmed, and that it is independent of learning and experience”, which is not the case with smells, as the scientist points out.
While researchers continue to study how these taste neurons interact with each other and regulate behaviors, Zucker points out that in humans taste is also innate and programmed, something proven in babies’ rejection of bitterness and their taste for sweetness.
“But, unlike most animals, we can learn to like bitter (like beer and coffee) or not to like sweet,” the researcher concludes.
What happens when taste reaches the brain?
In general, our understanding of taste is inferior to our knowledge of the other human senses. Understanding and describing our sensory perception of food requires knowing what mechanisms lie beyond the taste buds.
Taste stimulants in the mouth activate specific receptors on the tongue corresponding to each of the basic flavors: sweet, salty, sour, bitter, salty and the newly discovered umami.
The signal is then translated into the brain, but there is still much ignorance about how the peripheral signal is used by the central nervous system to encode flavor quality.
A team of researchers from the German Institute for Human Nutrition in Potsdam and the Charité University Hospital in Berlin, in Germany, are working on this, and they have revealed how taste is encoded in the patterns of neural activity in the human brain.
“The sense of taste is crucial for the choice of food and the formation of food preferences. Alterations in the perception of taste or the hedonic experience of taste can cause abnormal eating behavior and can lead to failure or excess nutrition “said lead research expert Kathrin Ohla.
”Our research aims to expand the knowledge of the neural mechanisms of taste perception and evaluation. This knowledge is essential for the development of strategies to moderate abnormal eating behavior”, adds this researcher, whose work is published in ‘Current Biology ‘.
Acceptance or rejection
But the phenomenon goes much further. The information sent by the senses when tasting food also reaches the brain amygdala. This region located in the temporal lobe is in charge of identifying whether a flavor is pleasant or not. And, therefore, if we accept it or reject it.
The fascinating fact that the same flavor can elicit completely different reactions in two people is public knowledge. For example, chocolate is a real pleasure for many people, while for some others it is intolerable. The amygdala is believed to be responsible for making this assessment.
However, it is true that the sense of taste and personal preferences evolve; either with practice or with the mere passage of time. That is, a child will find the taste of coffee completely unpleasant; Even as he grows up, he may begin to appreciate it and his attitude towards it radically changes.
In addition, there is a brain region that helps us remember if we have previously been in contact with that flavor. It is the limbic system. Thanks to the fact that it houses the sensory memory of the sense of taste, we can know if we have tried this food before and what we experience when doing it.
It is in this way that we can “educate our palate” to remember nuances and distinguish flavors. This is what happens when you take a wine or olive oil tasting course. As we try and become familiar with the different flavors, we are also able to remember and distinguish them.
What does it mean to know that we savor with the brain?
There is still a lot to know about how the sense of taste works. However, the findings described allowing us to make better use of our capabilities.
Thus, we know that the brain is capable of differentiating between the different types of flavors and condition our reaction. We also know that we can train the brain to remember and differentiate flavors and nuances; for which it would be advisable to eat and drink paying our full attention.
However, it remains to be discovered why food is individually enjoyable or intolerable to us. When we reach that milestone, we can make great strides in promoting healthy eating.
FAQS: Taste center in brain
What part of the brain is for taste?
The parietal lobe, located behind the frontal lobe, processes messages related to touch, taste, and temperature.
Where is the gustatory center of the brain?
The parietal lobe, located behind the frontal lobe, processes messages related to touch, taste, and temperature.
What part of the brain is responsible for taste and smell?
From the five senses of sight, touch, smell, hearing and taste, the parietal lobe finds out the messages you get. This part of the brain tells you what is part of the outside world and what is part of the body.
How do taste buds send signals to the brain?
The taste information is collected on the tongue, specifically the taste buds. These transform the sensory stimulus into an electrical impulse transmitted to the neurons connected to these receptors and carry it to the brain through their specific nerve pathway.
What part of the brain controls tying your shoes?
When you learn a new behavior, like tying your shoelaces, a region of the brain called the striatum orchestrates the series of actions: bend down, grab the laces, and tie the knot.
In this post we talked about the taste center in the brain, we will study how the sense of taste works and how the brain intervenes in this process of sensory information.
If you have any questions or comments please let us know!
Sébastien M. Crouzet, Niko A. Busch and Kathrin Ohla: Taste Quality Decoding Parallels Taste Sensations, Current Biology 2015, DOI: 10.1016/j.cub.2015.01.057
De Araujo, I. E., Rolls, E. T., Kringelbach, M. L., McGlone, F., & Phillips, N. (2003). Taste‐olfactory convergence, and the representation of the pleasantness of flavour, in the human brain. European Journal of Neuroscience, 18(7), 2059-2068.