When we talk about the senses, we generally think of the 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 fail to notice one important detail. We can also perceive our inner self. We notice headaches, nausea, internal itching, heart rate or muscle aches. And this is attributable to another sense: interception . In this article we will make a brief analysis of this concept.

What is interception?

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

Although sometimes separated from interception, the perception of pain or nociception would also be included within the ability to detect changes in body balance.

And not only that: although interception is generally thought of as something merely physiological, the truth is that it is largely linked to the experience of emotions. For example, it is not easy to determine whether we feel disgust if the emotion of displeasure is not accompanied by gastric-type sensations. And this is important when it comes to self-managing our emotions and behavior depending on the situation we are living and what it awakens in our body. It is also related to the perception of oneself as an entity.

Interoceptive receptors

In order to be able to perceive the stimulation, it is necessary that some kind of element is in charge of detecting it. In other words, there must be some kind 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 capture the breakdown of cells and send pain sensations) and reports the state of the organ or organs in question (these receptors can be affected by different stimuli or situations depending on the specific organ we are talking about).

These are generally receivers that remain silent, unless a disturbance occurs that activates them and causes them to react by sending signals. For example, we don’t usually pick up that our heart is going more or less fast unless we are nervous or accelerated, or that we lack water unless their lack causes them to generate sensations (which will cause the nervous system to trigger the perception of thirst to compensate.

Body systems in which this sensory function has been studied

The sense of interception extends to almost all 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 the investigation. In this sense, the interoceptive information allows us to have cardiac-type sensations such as heart frequency or acceleration, or blood pressure levels. This information allows us, for example, to realise that we are suffering a heart attack, or that our pulse is accelerating.

The perception of alterations in this system is mainly based on the action of the heart, sending the information to somatosensory receptors in the thorax . At a cerebral level, it is speculated that the right hemisphere may be more related to the conscious processing of cardiac information, but the research carried out has not reflected the existence of conclusive data in this respect.

2. Respiratory system

Lung interception 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. Also we can capture the existence of obstructions .

3. Gastrointestinal system

Movement, distension, temperature or even chemoception are some of the sensations linked to the interception 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 conscious perception .

Alterations in interception

Interception 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 in all people, which can cause them different problems.

These alterations can be either over- or under-stimulated: there may be a hypersensitivity that causes the interoceptive receptors to be activated with little stimulation or the receptors not to be activated, which would make it very difficult to adjust the behavioural response.

This is what happens with those people with congenital insensitivity to pain with anhydrosis or CIPA, not being able to perceive the suffering that the stimulation and (usually) the temperature generates. We can also find that the interception is altered in various psychiatric conditions, such as some hallucinations typical of psychotic episodes or in 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 interception. Journal of de Psicolo. Gral. y Aplic., 53 (1): 109-129