Interoception: listening to one's own body

When we talk about the senses, we generally think of all five dedicated to the perception of the outside world, that is, sight, hearing, smell, taste and touch. Thanks to them we perceive images, sounds, smells and pheromones, tastes, temperature and physical contact.

However, we often miss an important detail. We can also perceive our interior. We notice headaches, nausea, internal itching, heart rate, or muscle aches. And this is attributable to another sense: interoception. In this article we are going to make a brief analysis of this concept.

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What is interoception?

We understand by interoception the perception of the internal state of the organism, providing information on the functioning or dysfunction of the viscera and internal organs. It is a sense that helps us maintain homeostasis or body balance. Although often undervalued, interoception is vital for survival: thanks to it we can perceive that we are injured, that something is not going well in our body, that we need a greater supply of oxygen, that we need to drink water or eat or that we are sexually excited.

While it is sometimes separated from interoception, the perception of pain or nociception It would also be included within the ability to detect changes in body balance.

And not only that: although interoception is generally thought of as something merely physiological, the truth is that it is largely linked to the experimentation of emotions. For example, it is not easy to determine if we feel disgusted if the emotion of displeasure is not accompanied by gastric sensations. And this is important when it comes to being able to self-manage our emotions and behavior depending on the situation we live in and what awakens in our body. It is also related to the perception of oneself as one's own entity.

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Interoceptive receptors

In order to be able to perceive the stimulation, there must be some type of element in charge of detecting it. In other words, it is necessary that there is some type of biological receptor.

Interoceptive receptors are found throughout the body, usually in all major organs and blood vessels. They are found in the endoderm. The interoceptive system does not use a single type of receptor, but collects information from mechanoreceptors (sensitive to deformation), thermoceptors (which capture temperature), baroreceptors (sensitive to blood pressure) or nociceptors (which detect the breakdown of cells and send pain sensations) and report the status of the organs in question (these receptors may be affected by different stimuli or situations depending on the specific organ we are talking about).

These are generally receptors that remain silent, unless there is an alteration that activates them and causes them to react by sending signals. For instance, we do not usually understand that our heart goes faster or slower unless we are nervous or accelerated, or that we lack water unless their lack causes these to generate sensations (which will cause the nervous system to trigger the perception of thirst to compensate.

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Body systems in which this sensory function has been studied

The meaning of interoception extends to almost the entire set of organs and tissues in the body. However, the role of this sense has been explored more often in some specific body systems.

1. Cardiovascular system

The system that has received the most attention in research. In this sense, interoceptive information allows us to have heart-like sensations such as heart rate or racing, or blood pressure levels. These are information that allow us to realize, for example, that we are having a heart attack, or that our pulse is racing.

The perception of alterations in this system is based mainly on the action of the heart, the information being sent to somatosensory receptors in the chest. At the brain level, it is speculated that the right hemisphere may be more related to the conscious processing of the cardiac information, but the investigations carried out have not reflected the existence of conclusive data at the respect.

2. Respiratory system

Pulmonary interoception is another of the most studied, also linked to a large number of possible perceived sensations. Stretching and dilation, irritation and volume, pressure and movement are some of the information that is captured. Too we can detect the existence of obstructions.

3. Gastrointestinal system

Movement, distension, temperature or even chemoception are some of the sensations linked to the interoception of the digestive tract. Although much of the information that is processed in this system is usually conscious, it has been observed that some small stimulations may not generate awareness.

Alterations in interoception

Interoception is a sense of great importance that allows us to adjust our behavior to what is happening internally to our organism. However, it does not work properly for all people, which can cause different problems.

These alterations can be by excess or by defect: it is possible that there is a hypersensitivity that makes the receptors interoceptives are activated with little stimulation or that the receptors are not activated, which would make it very difficult to adjust the response behavioral.

This is what happens with those with congenital insensitivity to pain with anhidrosis or CIPA, not being able to perceive the suffering generated by the stimulation and (generally) temperature. We can also find that interoception is altered in various psychiatric conditions, such as in some hallucinations typical of psychotic episodes or manic episodes. Finally, the consumption of some drugs and / or intoxication by some toxic element can alter the interoceptive capacity of the organism.

Bibliographic references

• Quirós, P.; Grzib, G. & Conde, P. (2000). Neurophysiological bases of interoception. Magazine of de Psicolo. Gral. and App., 53 (1): 109-129