The upanishads, ancient yogic texts, speak of the mind and breath as two fish in tandem. Where one goes, the other does follow.
Steady the breath. Steady the mind.
Steady the mind. Steady the breath.
This is a foundation of yoga - your breath. The prana - life force,
Pranayama means the expansion of life force energy.
Prana -life force
yama - meaning to control or restrain
You have autonomy/control over your own breath - and thus your whole attention.
Mind and breath flow together.