Free Love 2.0 by Barbara L. Fredrickson Page B

efficient heart rate. After all, each successive heartbeat during an in-breath circulates more freshly oxygenated blood throughout your brain and body. Yet when you’re breathing out, a fast heart rate is not all that helpful because your supply of freshly oxygenated blood is waning. Here again, your vagus nerve steps in to help out. It can very gentlyapply the brake on your heart while you exhale, slowing your heart rate down a small degree. In turn your vagus nerve can gently let up on the brake while you inhale, letting your naturally high heart rate resume to grab all the oxygenated blood that it can get. This creates a subtle yet healthy pattern of cardiac arrhythmia: Your heart rate speeds up a bit when you inhale and slows down a bit when you exhale. This is the pattern that reflects your vagal tone, the strength or condition of your vagus nerve
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It characterizes the nimbleness with which your primitive, nonconscious brain holds the reins on your galloping heart.
    I give you this quick tour of vagus because this conduit within you, between your brain and your heart, has a story to tell about how attuned you are to sources of love in your midst. It even makes a quiet prediction about what illnesses may beset you and how long you’re likely to live. Your biological propensities for love and health, as we shall see, are intimately intertwined. Measured at rest, vagal tone also tends to be extraordinarily stable over time. For most people, it remains roughly the same year after year, rhythmically channeling them toward loneliness or social prosperity, sickness or health.
    That’s because people with higher vagal tone, science has shown, are more flexible across a whole host of domains—physical, mental, and social. They simply adapt better to their ever-shifting circumstances, albeit completely at nonconscious levels. Physically, they regulate their internal bodily processes more efficiently, like their glucose levels and inflammation. Mentally, they’re better able to regulate their attention and emotions, even their behavior. Socially, they’re especially skillful in navigating interpersonal interactions and in forging positive connections with others. By definition, then, they experience more micro-moments of love. It’s as though the agility of the conduit between their brains and hearts—as reflected in their high vagal tone—allows them to be exquisitely agile, attuned, and flexible as they navigate the ups and downs of day-to-day life and social exchanges. High vagal tone, then, can be taken as high loving potential. Indeed, this is whatdoctoral student Bethany Kok and I have found: Compared to people with lower vagal tone, those with higher vagal tone experience more love in their daily lives, more moments of positivity resonance.
    You might now be wondering whether you’re one of the lucky ones blessed with high vagal tone. If you are, that’s great. Yet even if you’re not advantaged with high vagal tone today, the latest science gives plenty of reason for hope. Just as you can build muscle tone through regular physical exercises, you can build vagal tone through regular emotional exercises of the kind I share in part II of this book. The key, once again, is the power of love.
    My students and I work together in what I call the PEP Lab, or the Positive Emotions and Psychophysiology Laboratory. Not long ago, we conducted an experiment on the effects of learning the ancient mind-training practice of loving-kindness meditation. Our study participants visited the PEP Lab at the University of North Carolina one by one, and we measured their vagal tone while they sat and relaxed for a few minutes. At the end of this initial laboratory testing session, we instructed participants how to log on to the study website each evening to record their emotions and social connections of the day. A few weeks later, by random assignment, we determined which participants would learn loving-kindness meditation and which