• The causal role of the amygdala with regard to fear and anxiety remains controversial.
• The amygdala inhibits fear evoked by elevations in CO2.
• Stimulation of the amygdala triggers a state of apnea outside of one’s awareness.
• Daily 5-minute breathwork and mindfulness meditation improve mood and reduce anxiety
• Breathwork improves mood and physiological arousal more than mindfulness meditation
• Cyclic sighing is most effective at improving mood and reducing respiratory rate