Andrew Huberman· PhD
there was some very clever experiments where they took it individuals and they artificially increased their oxygen uh levels but more specifically they increased their carbon dioxide levels by directionally they tried to manipulate it and they asked did those individuals start to yawn more because the idea would be if your blood oxygen is coming down and your carbon dioxide is starting to rise if this theory is correct you should start yawning with greater frequency and there was no difference whatsoever