We have been taught all our lives that we have five senses: sight, hearing, smell, taste and touch, and when there was talk of a sixth, it has always been associated with some supernatural quality. However, some experts speak of 7, 21 and even 32.
It all depends on how much you want to break down or group and how broad the definition of meaning is made... but even with all this, "five senses fall short" because "the plasticity of the brain is immense," Raquel Marín explains to La Vanguardia. , neuroscientist, professor of physiology and writer.
When we are cold, have a toothache, touch a specific toe without looking, or feel like a necklace is weighing down our neck, we perceive all of those sensations beyond what we hear, feel, taste, smell, or see. But the versatility of the human brain goes even further and allows us to notice physical objects without seeing them, have perception of time or experiences as peculiar as smelling a color or seeing a sound.
“The basis of everything is in how we define meanings,” Marín clarifies. For this neuroscientist, they are “biological tools that we need first to adapt to the environment and on the other hand to have all the internal information. These biological tools are fundamentally coordinated by neurons, which are those telltales that are distributed everywhere (not only in the brain, but also in the skin or in the viscera) that inform the operations center, which is the brain, so that we can make decisions. about".
About how many senses there are, experts have different theories. “You can say we have 32 senses if you break them down one by one, but if you group them together, you have less. It's like if you say red meat or break it down into ribeye, rib, sirloin... if you group them together you have less left than if you count each piece separately," exemplifies the neuroscientist.
“Even so, with five senses we would fall short,” since these are those related to exteroception, that is, “those that allow us to connect, inform ourselves or interact with the external environment,” which would be sight, hearing, smell, taste and touch.
In addition to these “the classic senses”, there are many others, whether grouped or not, that help us relate to the environment and ourselves. Marín talks about 4 major classifications of the senses in which there is a lot of scientific consensus: exteroceptors (the traditional ones, those that inform us about the outside) and interoceptors (which allow us to know and look inside ourselves). Within the latter we would find interoception itself, proprioception (which refers to awareness of our own body) and nociception (which is the sense that perceives pain through the skin, organs and joints).
But once you enter each of these large blocks, a large number of senses appear that help us make decisions through the information they provide us. “There is a much greater neurological diversity than we believe,” pointed out Pablo Barrecheguren, a doctor in biomedicine specialized in neurobiology and scientific communicator in another interview with La Vanguardia, and the more one investigates, the more fascinating meanings are described.
Experts who are not fond of breaking down classifications put into this bag a large number of very different meanings that others take, since the definition is very broad. Interoception is the sense that brings together the sensations of what happens inside us, in the organs of our body.
Thanks to interoception we experience hunger, thirst, the urge to urinate, sexual arousal, as well as tachycardia, nausea or any other abnormality within us. The lungs or brain do not hurt themselves, but this sense informs us of their state and can also help us combat certain very common ailments such as anxiety.
“Interoceptive exercises related, for example, to breathing, are those that are now being promoted a lot in relation to anxiety and nervousness,” “this is being promoted a lot as a result of some large-scale studies in which it seems that people who "Those who suffer from anxiety often relax more when they begin to listen to their own heart and capture those internal sensations and begin to correct them." This can be done thanks to the interoceptive senses.
Can you touch the tip of your nose with your left hand and your eyes closed? This is thanks to the sense of proprioception, which refers to body awareness and informs the brain of the position of the muscles, the length, the stretch at that moment, etc.
This is "another of the large groups and here we would encompass things related to motor activity" (posture, balance...), here we could include senses "that are quite fashionable and that have to do with the postures of the face, the lips, hands.”
Kinesthesia (or kinesthesia) would be an example of a sense that is sometimes included and sometimes separated from this category, which is the perception of movement and helps us maintain balance and be aware of space and time. This allows us, for example, to jump just enough to reach a specific point, for which we must take into account distance, weight, position and of course, balance.
Baryesthesia may or may not also be within the category of proprioception, since it is the sense that makes us feel the weight and pressure on our body, such as a necklace on our neck or a blanket on the bed.
When your back or head hurts, you are not using the classic sense of touch, you are not touching anything, but nociception has come into play, another of the large groups for which there is quite a consensus. These are painful sensations that “are fundamentally three groups; skin or superficial pain, somatic pain of the muscles, tendons and bones and then internal pain", all of this is managed by the brain "because the brain or the lungs do not hurt themselves" even if they receive the information that something it's happening.
The neuroscientist also tells something curious, and that is that “an emotion can modify pain.” “There is no doubt, the way you breathe can also change the way you manage that pain: if you are going to get an injection and you are gasping, it will hurt more than if you try to take a deep breath, hold your breath, and exhale,” he explains.
How long have you been reading this article? Your sense of chronoception will give you an approximate answer depending on how well you have developed this sense, but also on other factors.
Chronoception is the sense of time and is also an explanation for whether time passes quickly or slowly because “it is very marked by emotions,” explains the professor in physiology. “If you're waiting to go into an operation, it's going to seem like forever, while if you spend the whole afternoon with friends having drinks it goes by in a flash,” she exemplifies.
Thermoception is the mechanism by which we perceive heat or its absence. This sense is the relationship with the thermal sensation that can be through the skin or through the internal organs, although, for scientists who advocate divisions, they would separate what thermoception is (feeling heat or its absence in the skin) of thermoalgesia (which allows us to feel the internal body temperature).
Thus, the cold of ice on the back, the warmth of someone else's feet in bed or the awareness of having a fever occur when this sense intervenes.
Have you ever experienced smelling a color or seeing a sound? Those who have developed the sense of synesthesia can do it, but curiously it is the only sense that is not universal, not everyone has it and “it occurs more frequently in children,” Marín specifies.
“In music they appear as colors or in flavors they are also associated with colors. This is highly studied in the kitchen to achieve a synesthetic sensation because this enhances the experience,” says the neuroscientist. “More studies would be required but it is complicated because it is not something so palpable to experiment with,” she says.
The word synesthesia is also a rhetorical figure that very graphically exemplifies what this unusual sense consists of. In literature it is the attribution of a sensation to a sense that does not correspond to it, such as “shiny green” (hearing a color) or “sweet words” (tasting a sound).
The echolocation sense is the ability to locate objects through reflected sound. It is similar to the operation of a sonar, which emits a vibration that bounces revealing the position of people or things.
"Although it occurs more in other animals such as cetaceans or bats, it also occurs in humans, for example in blind people who, without sight, can detect the presence of a physical environment and a better location of the environment to make up for the lack of vision,” explains Marín.
Echolocation in humans is the ability to detect objects in their environment by detecting through the echoes created by sounds that are actively emitted, for example by snapping the fingers, making them with the mouth or stomping with the feet. It seems complicated but it works, proof of this is Daniel Kish, an American expert on the subject and president of World Access for the Blind who has developed this technique and teaches it to other blind people to be able to interact with the environment.
Kish even practices hiking and mountain biking despite being blind since he was a baby. His experience has inspired more studies on the subject, such as one carried out at the University of Alcalá in Madrid that analyzes different ways of emitting organic sounds for the greatest effectiveness of human echolocation.
Breaking down curious meanings in conversation with La Vanguardia, Marín speaks of an “anticipatory sense.” “If you are hungry and you start to smell bread or see an empanada that you like, you start to salivate as if you were preparing for food and that is an anticipation because there is no food in your mouth but your body begins to secrete saliva” “or a 100-meter runner, if you take their heart rate at the start, they are already at more than a hundred even though they haven't started running yet.”
There are references to senses that go beyond the perception of our own interior that allow us to perceive the interiority of others. We asked the neuroscientist if this is fiction or science fiction and she explained this to La Vanguardia: “There is no doubt that in the human brain there is what is called brain synchronization, this has been demonstrated and has a very simple explanation: being beings social and also developing a large number of different tasks, the tasks are learned more quickly if they are not learned only through verbalizing or visualizing, but also through synchronizing the brains to know how those brains or sensations are when it comes to developing A homework. “This allows us to be more effective in teamwork.”
"That is known, when you carry out tasks together there is a modification in brain patterns generating a synchronization of those brain waves to make the joint task more effective." This “also happens when sleeping as a couple: if you synchronize your brain waves with that of your partner, the mental rest will be greater than if that synchronization does not exist,” says Marín.
