Breathing through the right nostril will also feed more blood to the opposite hemisphere of the brain, specifically to the prefrontal cortex, which has been associated with logical decisions, language, and computing.13 Inhaling through the left nostril has the opposite effect: it works as a kind of brake system to the right nostril’s accelerator. The left nostril is more deeply connected to the parasympathetic nervous system, the rest-and-relax side that lowers blood pressure, cools the body, and reduces anxiety.14
