From Huff Post. There is alot of good info here. The quote is from towards the end of the article (which starts out talking about addiction). For me, its great news to hear all the listed ways (click the link) to activate the parasympathetic nervous system (think rest and digest), to stimulate oxytocin and GABA. And its great to see that the simplest way is to just breathe in and out slowly, 3-6 breaths a minute (approx). That can be done any place, any time by just about anybody. if you practice it when you are not stressed then it will be easier to access and to remember in stressful moments. This is not natural breathing, or the kind of breathing encouraged for meditation. Its a therapeutic breathing technique we can employ to balance our nervous system and bring more calm and relaxation.

Fortunately natural, low-cost techniques can activate our innate recharging, healing, and self-soothing systems: the parasympathetic nervous system PNS; the cuddle hormone, oxytocin; the calming neurotransmitter, gamma-aminobutyric acid GABA; and feel-good endorphins. When we feel threatened, the sympathetic nervous system SNS revs up, preparing for fight or flight, increasing heart rate and respiratory rate and heightening tension and alertness. Once danger has passed, the SNS should stand down while the PNS turns on to slow the heart and respiratory rates, relax the mind and body, repair damaged tissues, reduce inflammation, and induce feelings of safety. Unfortunately, in this high-stress world, our SNS is overactive, while its counterpoint, our PNS, is underactive. How can we amp down the SNS and crank up the PNS?

It is a fact that the PNS can be turned on by warm fuzzies: stroking, petting, hugging, holding a teddy bear, walking in the woods, yoga, qigong, meditation, or loving thoughts and feelings. Giving and receiving caretaking and helping others also mobilize the PNS [3]. In addition, warm fuzzies increase the release of oxytocin, the neurohormone that facilitates bonding. Moreover, activating the PNS increases activity of GABA, the inhibitory neurotransmitter, and improves the ability of regulatory centers prefrontal cortex and insular cortex to control the over-reactivity generated in the emotion processing centers amygdala and hippocampus. Many addiction treatment programs include community service because helping others fosters a sense of meaningful connection, self worth, and the ability to experience the healthy addictive pleasures of giving.

There’s more good news. Changing the pattern of our breathing is probably the fastest way to jump start the PNS and thereby increase oxytocin and GABA [4]. For most people, breathing gently at three to six breaths per minute with equal inhalation and exhalation induces a calm, alert state within 10 minutes [5]. This pattern has been called coherent breathing or resonant breathing because it induces the optimal balance between the SNS and PNS — a calm, alert, focused state of mind and synchronization of brain waves with respiration and heartbeat. Furthermore, breathing at this rate maximizes the amount of oxygen the lungs extract with each breath, leading to enhanced sports performance. Gadgeteers offer a plethora of electronic devices that help correct imbalances in stress response systems and brain wave patterns.

via Patricia L. Gerbarg, M.D.: Reprogram With Healthy Habits and Warm Fuzzies: Trumping Addictions and Compulsions.