Taste pleasure

taste pleasure

The interpretation of taste by the brain begins with the multiple function organ : the tongue. Indeed, it is essential in our language learning, our ability to feed, it brews food and sends it into the esophagus to the stomach. Tongue is also the taste and for that we have to thank the taste papillas. There are two types, taste papillas and tactile papillas.

 The tactile taste papilla serve us, for example, to discern soft drinks, crispy foods, etc.[pic 1]

 The taste papillas, as their name suggests, are related to the nerve  of taste thanks to the taste buds that are sensitive to certain substances and create the range of flavors: bitter, sweet, acid and salty. These different flavors are perceived by different parts of the language

The second step of taste interpretation is transduction: The origin of the different perceptions of flavors comes from the transmission of information of taste to the brain that is possible thanks to the receptor cells. They are contained in the 3 to 5 buds of each papilla. The canals of the receivers will close and open to let ions pass or not. For example, the acid taste is characterized by the presence of H + ions. The information is then brought to the brain by the glossopharyngeal nerve, enters the thalamux and reaches the cortex which has regions that specifically respond to each of the primary flavors. This is how different flavors are perceived. Talking about pleasure, the informations received from the nose and the tongue are transmitted by the dopamine which is the neurotransmitter of pleasure.[pic 2]

We must know that the attraction to sweetness and repugnance to bitter is actually a biological predisposition inscribed in our genetic heritage due to the fact that sweet is associated with an energy ration, while the bitter is associated to toxic molecules.

However, it would be incomplete to say that taste is limited to the taste papillas. Indeed, smell and vision play an essential role because they guide the choice of food.

View is not technically part of taste but it surely influences it. Appareance of foods and drinks make people see flavors before they taste them. In a classic experiment, French researchers colored a white wine red with an odorless dye and asked a panel of wine experts to describe its taste. The tasters described the wine using typical red wine descriptors rather than terms they would use to evaluate white wine, suggesting that the color played a significant role in the way they perceived the drink.

After leading an experiment, we’ve determined that taste pleasure is linked to the price of the food that you’re eating. In order to do this, we’ve placed 2 bowl, one with « bas de gamme» and the other one « haut de gamme » which means cheap and expensive. They were both the same, we’ve only put different names.

We’ve expected the results. 75% of the participants prefered the “haut de gamme”chocolate saying that he was better in mouth, more tasty, more refined even some said they liked it because it was more expensive. The majority (of 94%) said that they would definitely eat it again.

The first stage of olfactory perception begins at the level of the olfactory epithelium located in the upper part of the nasal cavity. These neurons bring the information to olfactif bulbs situated in the base of the brain then to the olfactif cortex where a « picture » of the odor is made. The informations from the good odors are dirigesd to the orbito-frontal cortex which is the cortex of pleasure and emotions. [pic 3][pic 4]

Acquiring information related to scent through the back of the mouth is called retronasal olfaction—via the nostrils it is called orthonasal olfaction. Both methods influence flavor; aromas such as vanilla, for example, can cause something perceived as sweet to taste sweeter. Once an odor is experienced along with a flavor, the two become associated.

Salivation is part of the experience of consuming food, and the more a food makes you salivate, the more it will fill your mouth and cover your taste papillas. For example, emulsified foods like butter, chocolate, salad dressing, ice cream and mayonnaise cause a salivary response that helps excite your taste papillas.

This is one of the reasons why many people enjoy foods with sauce or icing. As a result, foods that stimulate salivation enchant your brain and taste better than those who do not.

As well, the interaction between serotonine and carbohydrate is a mecanism linking pleasure and alimentation. In fact, Serotonine is a chimic substance which allow neurons to transmit a message and has an important role in the regulation of the emotions, that’s why chocolate has a soothing power.

aesthetic pleasure

For many philosopher ,beauty did not suit what we perceive, otherwise we could see indoor beauty even if his ugly .

Its very difficult to charactarize beauty because ‘the elders’ have an aesthetic judgment associate values like symmetry , the proportion, the number of gold..

Many researchers try to determine neuronal mechanism involved in the aesthetic judgment and what is the specific brain mecanism which make such a judgment ( if its pretty or not)

They use an IRM to determine which zone of the brain are activated when they saw the image that we gave them

They find that 3 cerebrals regions are activated whatever the nature of the image observed ( face, landscapes, abstract figure etc..)

The first is the cortex orbito-frontal which play a major role in the perception of feeling  of reward , secondly there is the motor cortex involved in the command of voluntary movement, then the last is the cortex parietal involved in the phenomena of visual attention.

[pic 5]

This picture show you the different regions activated : the more the image was pretty the more the cortex orbito-frontal was activated

[pic 6]

   The more the image was ugly the more the motor cortex was activated

Indeed, the image jugde pretty also activates cerebrals airs located in the reward circuit.

After the sensory treatment by the cortex, a particulary region of the mesencephal named ATV increase then dopamine is released in the accumben nucleus , in the septum , the amydgale and the prefontral cortex.

     [pic 7]

Like we already know the different regions are connected by the reward bundle, in neuro-atomics terms this bundle belongs to medium forebrain bundle (MFB) so the activation leads to the repetition of rewarding action.

Consequently, we can say that the reward circuit  provides necessary motivation in mostly of our behavior. Any involved regions are specifically i n the aesthetic jugdment ,and their activity varies according to the judgment.

Before , the reward circuit combines the perception of beauty with a pleasant sensation, the reception of this reward is traduce by a release of dopamine .

She leads to memorization of this beauty and the person is brought to repeat this behavior which provides him pleasure.

There is a dissociation between :

- brain areas of the reward circuit are more activated by the reward type ‘aesthetic’

- the areas treating indifferently any type of reward

[pic 8]

This image identifies areas of the reward circuit that treats all types of rewards whatever is the nature.

We finds areas of the reward circuit : the ventral striatum which comprises the nucleus accumbens , an area of the mesencephalon, the anterior part of the insula and the anterior cingulate cortex.[pic 9]

Here is the dissociation between areas of the reward circuit which are activated by reward of type aesthetic ( in green) and others areas that treat indifferently every type of reward ( in red) .

To conclude in the reward circuit, there are specific brain areas for aesthetic rewards.

And now, we’re going to talk about the gambling addiction and why does it affect the pleasure.

To start, you may ask, what is gambling addiction ?

[pic 10][pic 11]

Gambling is a diverse activity, so different types of gambling addiction exist as well. It is not always obvious when someone is addicted to gambling. Contrary to popular belief, the act of gambling is not restricted to slot machines, cards and casinos. Purchasing a lottery ticket, entering a raffle or making a bet with a friend are also forms of gambling.