The way we breathe and the breathing phase (inhalation or exhalation) have an impact on our memory. This is the surprising finding of an American study published in 2016.
We already knew about olfactory oscillation, a phenomenon that causes the neurons in the olfactory system to activate when air enters the nose through the receptors at the tip of the nasal hairs. It was also known that there were four types of olfactory oscillations, some of which were associated with learning and memory.
What the 2016 study highlighted is the fact that information is better stored if, when you read the information to be memorized, you inspire through your nose. Exhalation through the nose as well as breathing through the mouth (inhalation and exhalation) do not have the same effect, since it is the entry of air through the nostrils that allows olfactory oscillations.