Interoception means sensing internal organs – True

About 150 years ago, the concept ... concept of homeostasis[2]. More recently, interoception has been commonly referred to as the process by which the nervous system senses and integrates information about the inner state of the body[3]....

Identifying the state of the body represents a problem that cannot be solved by pure sensing because afferent signals from body sensors (interosensations) are not only noisy but often ambiguous (89). Recent computational theories suggest that interoception deploys Bayesian inference to address this challenge (36,37,44,45,90,91) (Figures 3 and 4). Specifically, the brain is assumed to construct a so-called generative model of interosensations that combines a predictive mapping (from hidden bodily states to interosensations) with prior information (beliefs or expectations about bodily states represented as probability distributions).

In much the same way that your brain sees sights, feels things that touch your skin, and hears sounds, it also produces your body’s inner sensations, such as a gurgling stomach, a tightness in your chest, and even the beating of your heart. Your brain also models other sensations from movements that you cannot feel, such as your liver cleaning your blood. The construction of all your inner sensations is called interoception and, like exteroception, it proceeds completely outside your awareness.

Interoception — your brain’s representation of sensations from your own body — is the sensory consequence of this activity, Barrett says, and is central to everything from thought, to emotion, to decision making, and our sense of self.

Studies on neuroanatomical pathways and cortical regions associated with interoception suggest that perceptual sensations arising from the internal environment of the body has a primary dedicated cortex receiving signals from the peripheral nervous system through neuroanatomical pathways, and ...

HEP amplitudes over the left parietal cortex (126-186 ms after the R-peak) differentiated trustworthy from untrustworthy faces only during trust evaluation, not symmetry evaluation, providing preliminary evidence consistent with context-dependent modulation of interoceptive neural signals. Trust evaluations also elicited larger SCRs for untrustworthy faces, and HEPs and SCRs showed trial-by-trial associations, suggesting a relationship between bodily arousal signals and interoceptive processing during social-affective evaluation.

However, recent work on gut and hippocampal function [17], which tested the hypothesis that specific interoceptive signals are transported via the vagus nerve to the hippocampus to influence memory function, provides an elegant example on how one could begin to address this challenge. The second category of interoceptive functions includes information flow from the brain to the body to exert bodily effects.

At the base of the skull, the cell bodies of vagus sensory neurons are intermingled, but as their signal-transmitting axons move into the NST they form what Liberles calls a “remarkable map” of internal organs. From there, signals can flow to the parabrachial nucleus, which sorts through those inputs, along with information from the spinal cord and some of the external senses. The signals can also travel to higher brain regions involved in emotion, memory, and decision-making. But they don’t always do this, which may be why not all interoceptive signals reach conscious awareness.

At the base of the skull, the cell bodies of vagus sensory neurons are intermingled, but as their signal-transmitting axons move into the NST they form what Liberles calls a “remarkable map” of internal organs. From there, signals can flow to the parabrachial nucleus, which sorts through those inputs, along with information from the spinal cord and some of the external senses. The signals can also travel to higher brain regions involved in emotion, memory, and decision-making. But they don’t always do this, which may be why not all interoceptive signals reach conscious awareness.