Summary
Mouth breathing causes structural and health problems; nasal breathing filters air and produces nitric oxide. Slow breathing at 5-6 breaths per minute optimizes CO2 tolerance. Mouth taping at night can improve sleep quality.
Key Points
- Mouth breathing causes facial structure changes and health problems
- Nasal breathing filters air and produces nitric oxide
- Slow breathing (5-6 breaths/min) optimizes CO2 tolerance
- Mouth taping at night can improve sleep quality
- Breathing affects everything from anxiety to athletic performance
Key Moments
Dr. Feldman: the pre-Botzinger complex fires every breath and drives diaphragm activation
Every breath starts with neurons in the pre-Botzinger complex firing, which then activates the diaphragm and intercostals. Nose vs.
"I don't think we fully have the answer to that. Clearly, there are differences between nasal and mouth breathing."
The brainstem CO2 sensor protects the brain from pH shifts that would throw it out of whack
A second breathing oscillator near the facial nucleus was initially thought to be a CO2 chemoreceptor.
"That is, we want to keep carbon dioxide levels, particularly in the brain, at a relatively stable level because the brain is extraordinarily sensitive to changes in pH."
Vagus nerve stimulation reduces depression; breathing rhythm is a natural vagal signal
Artificial vagus nerve stimulation helps depression.
"But the other thing with the hyperventilation, hypoventilation, or the apnea, is your CO2 levels are going from low to high."
Episodic hypoxia vs. breath holds: CO2 stays stable in one but rises in the other
During breath holds, both O2 drops and CO2 rises. During episodic hypoxia, O2 varies but CO2 stays normal -- a key distinction.
"When you hold your breath, your oxygen levels are dropping, your CO2 levels are going up. When you're doing episodic hypoxia, your CO2 levels are going to stay pretty normal. Of course, you're still breathing. It's just the oxygen levels are gone. So unlike normal conditions, which you described before, where oxygen is relatively constant and CO2 is fluctuating depending on emotional state and activity and things of that sort. In episodic hypoxia, CO2 is relatively constant, but you're varying the oxygen level coming into the system quite a bit. I would say it's relatively, I would say CO2 is relatively constant, but it's not going to go in a direction which is going to be significantly far from normal."
Nasal breathing improves memory via hippocampal activation during inspiration
Studies in the Journal of Neuroscience show that restricting breathing to the nose activates the hippocampus during inspiration, improving memory.
"One looking at olfactory memory. So that kind of made sense because you can smell things better through your nose than your mouth, unless you're some sort of elk or something where they can, presumably they have some sense of smell in their mouth as well. But humans generally smell with their nose. That wasn't terribly surprising, but there was a companion study that showed that the hippocampus, terribly surprising, but there was a companion study that showed that the hippocampus, an area involved in encoding memories in one form or another, was more active, if you will, and memory and recall was better when people learned information while nasal breathing as opposed to mouth breathing. Does that make sense from any mechanistic perspective?"
