Most of us also know that we can control our breath consciously, choosing the speed at which we breathe and even stopping it altogether, for a short while at least. This conscious control of our breath is done by the somatic nervous system, the part that controls voluntary functions like walking, writing or playing baseball. It is located on the surface of the brain at the very back of the frontal lobe, in a place called the motor cortex.
Whenever we consciously control our breathing, the motor cortex overrides the brain stem. This process takes a lot of effort from the brain, which is why it has the effect of focusing us. As an experiment, try to control your breath while doing a math problem in your head. It is difficult. When we consciously control the breath, the brain becomes still.
This phenomenon is one of the key principles of pranayama (breath control) and even the most simple breathing exercises. Even for a true beginner, counting the breath or trying to control it at all calms the mind and leaves them feeling very focused.


