SPOILER ALERT! ~ Interoception is the awareness of internal sensations (bodily sensations). ~ Interoceptive components of breathing include two cortical pathways (in the brain): the discriminative and the affective pathways. ~ The discriminative pathway relays objective information about breathing such as inspiration, expiration, etc… ~ The affective pathway carries the subjective information about breathing such as gasping for air, shallow breathing, etc… ~ The affective pathway includes brain centers involved in emotion processing including the amygdala, which is known to play a major role in anxiety ~ Research on interoception and anxiety suggests that anxious people misread body signals ~ Interoceptive signals from the breathing system become less clear/less perceptible under anxiety, resulting in misinterpretation of breathing signals or lack thereof. ~ These findings could explain why some panic attacks feel like they occurred "out of the blue".
Research on the neural systems underlying breathing highlights two primary cortical pathways (i.e., referring to how the information related to breathing that comes from the various sensors in the body is processed in the brain), which are the discriminative and the affective pathways.
THE DISCRIMINATIVE PATHWAY Vs THE AFFECTIVE PATHWAY
The former (i.e., the discriminative pathway) relays information about respiratory proprioception (i.e., raw information from the body) and the latter (i.e., the affective pathway) carries subjective information about respiration, such as the perception of effort breathing (i.e. gasping for air) and respiratory status (i.e., deep or shallow breathing).
Furthermore, as expected the affective pathway includes limbic structures (i.e., referring to parts of the brain involved in the processing of emotions) such as the amygdala, rendering it particularly vulnerable to emotional influences. Both pathways contribute to the interoceptive component of breathing (i.e., the feeling of what is going inside the body), and both provide a solid platform to study the connection between anxiety and breathing.
THE EFFECTS OF ANXIETY ON INTEROCEPTION
Research on the link between interoception and anxiety indicates that anxious individuals assess body signals inaccurately due to their inability to distinguish those signals associated with aversive consequences from those that reflect normal ongoing bodily changes (e.g., not distinguishing between a stomach ache due to food poisoning versus butterflies in the stomach).
Thus, the question whether it is possible to misinterpret breathing signals comes to mind. The answer to that question is implied in reports of anxious individuals exhibiting altered breathing characteristics such as an increased flow of breathing and a decreased expiration time, which suggests a role for anxiety on either or both the cortical pathways of breathing.
Additional support for this theory came earlier with the conclusion that anxiety appears to blunt interoceptive signals until there is a substantial deviation from respiratory homeostasis. This theory also helps explain the perceived ‘out of the blue’ increased anxiety that occurs as a result of not readily intercepting homeostatic changes, which in turn prevents adaptive adjustments from being implemented. Thus, it is likely that anxiety contributes to misinterpreting breathing signals.
Paulus M. P. (2013). The breathing conundrum-interoceptive sensitivity and anxiety. Depression and anxiety, 30(4), 315–320. https://doi.org/10.1002/da.22076