Overbreathing leads to a hyperexcitable brain with reduced efficiency in detecting and learning information, and focusing.

“As a consequence, they overbreathe. And as I told you before, when people overbreathe, their brain becomes hyperexcitable at the level of the background noise. And yet they are less efficient at detecting and learning information. We'll get into the specific studies that really illustrate the learning aspect a bit later. But they are less efficient at detecting and learning information, at focusing, and so on as a consequence of this overbreathing and the hyperexcitability that it causes.”