The breathing conundrum – interoceptive sensitivity and anxiety – Oct 2013 – free full-text PMC articlle
Various controlled breathing practices seem to have powerful effects on the nervous system, probably through stimulation of the vagus nerve.
This review focuses on the relationship between breathing and anxiety.
Several anxiety disorders have been associated with
- altered breathing,
- perception of breathing and
- response to manipulations of breathing.
Both clinical and experimental research studies are reviewed that relate breathing dysfunctions to anxiety. Altered breathing may be useful as a physiological marker of anxiety as well as a treatment target using interoceptive interventions.
Anxiety and Breathing – The Interoceptive Connection
Anxiety is an emotional state associated with
- a cognitive component of increased attentional focus on threat to the integrity of the individual ,
- a complex sympathetic arousal response , and
- behaviors aimed to avoid stimuli or contexts predictive of threat to the individual .
Breathing is one of the most fundamental physiological functions of the human body. Moreover, it is an integral component of interoceptive processing, i.e.
- the sensing of the physiological condition of the body ,
- the representation of this internal state  within the context of ongoing activities, and
- the initiation of motivated action to homeostatically regulate the internal state .
Changes in breathing can be both the consequence of an increased level of anxiety (e.g. ) as well as the source of threat experienced by the individual, which, in turn, leads to increased anxiety .
Thus, assessing breathing might be a useful physiological marker of the level of anxiety but can also serve as an experimental tool to influence anxiety levels.
The elucidation of the physiological mechanisms and neural pathways regulating breathing can help to better delineate how an emotional state emerges from the interaction between the body and the brain.
The physiology and neurobiology of breathing is a rapidly progressing field that provides an experimental scaffold to study the biological basis of how the body and the brain interact.
More importantly, the experimental tools available enable one to begin to delineate how specific emotions emerge as a consequence of the body brain interaction.
There are some intriguing initial findings of altered breathing perception, different breathing patterns, and changes in the neural signature related to breathing in individuals with high anxiety or anxiety disorders.
However, much work needs to be done to better delineate the direction of the relationship between breathing and anxiety as well as to evaluate how brain systems respond to the modulation of breathing as a powerful intervention to attenuate levels of anxiety
A deeper understanding of anxiety and associated disorder can emerge from investigating the molecular characteristics of peripheral lung receptors to the influence of controlled breathing during mindfulness.