Because the physical act of breathing stimulates the vagus nerve, it has a powerful effect on our whole nervous system.
Autonomic nervous system dysfunction is associated with most disorders seen in pediatric and adult psychiatric practice, including anxiety disorders, depression, PTSD, hostility and aggression, attention deficit disorders, and autism spectrum disorder.
Increasing the underactivity of the parasympathetic branch and correcting the erratic or overactivity of the sympathetic branch can improve stress resilience and ameliorate psychological and physical symptoms.
From Wikipedia, a quick description of these two parts of our Autonomic Nervous System:
The sympathetic nervous system is often considered the “fight or flight” system, while the
parasympathetic nervous system is often considered the “rest and digest” or “feed and breed” system.
In many cases, both of these systems have “opposite” actions where one system activates a physiological response and the other inhibits it.
Although prescription medications (eg, anxiolytics, antidepressants, antipsychotics) can dampen overactivity of the sympathetic nervous system (SNS), they cannot correct underactivity of the parasympathetic nervous system (PNS).
Most parasympathetic pathways are contained in the vagus nerves, the 10th cranial nerves, whose extensive branches innervate all internal organs and glands.
Studies have shown that voluntarily regulated breathing practices (VRBPs) can significantly improve symptoms of
- anxiety disorders,
- trauma- and stressor-related disorders,
- depressive disorders,
- and other conditions.
VRBPs can also be used to restore feelings of meaningful connection, bonding, and love for patients who experience states of disconnection or emotional numbing—common sequelae of trauma and loss.
Neuroanatomic substrate for effects of VRBPs on sympatho-vagal balance
In 2005, we proposed a neurophysiological model to account for the observed clinical effects of VRBPs on sympatho-vagal balance and psychological symptoms.
Specific VRBPs entail changing the pattern of breathing, thereby changing the interoceptive messages sent through vagal afferent pathways (from the peripheral to the CNS), via brainstem nuclei to the
- limbic system,
- prefrontal cortex,
- insular cortex, and
- networks involved in perception, interpretation, emotion regulation, and cognitive function.
The respiratory system is rich in
- stretch receptors (eg, inside alveolar walls, thoracic musculature, diaphragm),
- bronchial airways,
- chemoreceptors, and
Two-way neural pathways between the respiratory system and the brain are of necessity strong and rapid. Interoceptive information derived from breathing patterns has global effects on brain function with the potential to rapidly change how we feel and think.
Slow breathing practices increase vagal influence on heart rate variability
- slow, gentle breathing is calming and increases parasympathetic tone;
- rapid, forceful breathing is activating and increases sympathetic tone.
The Table summarizes breath practices commonly used in the US.Three of the most clinically useful slow VRBPs (3 to 10 breaths per minute, cpm) are
- Qi Gong breath 4-4-6-2,
- coherent breathing, and
- breath moving.
Qi Gong breath 4-4-6-2.
Paces breath cycle: 4 counts on the inhale, 4 to pause, 6 on the exhale, and 2 to pause. This calming practice activates the PNS. It can be used in combination with a Qi Gong posture to rapidly reduce anxiety, rage, and suicidal thoughts.
Coherent breathing or resonant breathing
Gentle natural breathing in and out through the nose with equal length of inspiration and expiration at a rate that optimizes sympatho-vagal balance (heart rate variability), between 4.5 and 6 bpm for most adults.
For more sedative effects at bedtime, the length of exhalation is doubled.
induces a mental state of emotional calmness with mental alertness and enhanced cognitive processing.
…is an advanced practice in Qi Gong and other traditions, wherein one uses the imagination to move the breath and attention to different parts of the body in circuits.
Breath moving can augment the benefits of coherent breathing in the treatment of psychological conditions, physical injuries, and pain.
Combining breathing techniques with conventional treatments
Breathing practices enhance conventional treatments.
One advantage of breath practice is that it does not matter what the mind is doing. If the person simply paces his or her breathing to 5 cpm using a sound track, the anxious ruminations will quiet down and cognitive functions will improve.
Once the mind is quiet and calm, it is much easier to focus on mindfulness, meditation, and psychotherapy.
Although cognitive behavioral therapy is beneficial in many cases, it has some limitations. A top-down cognitive approach is not always able to control anxiety.
That’s because anxiety IS cognitive. And for some of us, threatened with the loss of our only effective pain relief, we have plenty to be realistically anxious about, in which case thinking only worsens anxiety.
Coherent breathing, as a bottom-up approach, is more effective because it bypasses intellectual processing and utilizes more rapid and powerful pathways between the brainstem and the emotion regulatory circuits.
Significant improvements in emotion regulation and stress response have been attributed to the effects of afferent signals from the respiratory system, transmitted by vagal afferents to the hypothalamus, limbic system, thalamus, and prefrontal and frontal cortex.
Breath practices have the potential to open a portal to correct imbalances of the stress response systems and to facilitate emotion regulation, social engagement, bonding, and recovery from trauma.
For more information on the importance of the vagus nerve and ubiquity of its effects, see these previous posts: