By Sarah Garfinkel – When considering the senses, we tend to think of sight and sound, taste, touch and smell. However, these are classified as exteroceptive senses, that is, they tell us something about the outside world. In contrast, interoception is a sense that informs us about our internal bodily sensations, such as the pounding of our heart, the flutter of butterflies in our stomach or feelings of hunger.
The brain represents, integrates and prioritizes interoceptive information from the internal body. These are communicated through a set of distinct neural and humeral (ie, blood-borne) pathways. This sensing of internal states of the body is part of the interplay between body and brain: it maintains homeostasis, the physiological stability necessary for survival; it provides key motivational drivers such as hunger and thirst; it explicitly represents bodily sensations, such as bladder distension.
But that is not all, and herein lies the beauty of interoception, as our feelings, thoughts and perceptions are also influenced by the dynamic interaction between body and brain.
The shaping of emotional experience through the body’s internal physiology has long been recognized. The American philosopher William James argued in 1892 that the mental aspects of emotion, the ‘feeling states’, are a product of physiology. He reversed our intuitive causality, arguing that the physiological changes themselves give rise to the emotional state: our heart does not pound because we are afraid; fear arises from our pounding heart. more>