Born to Be Good: The Science of a Meaningful Life

James’s thesis reversed this sequence of bodily response and experience: “My thesis,” James proposed, “…is that the bodily changes follow directly the perception of the exciting fact, and that our feeling of the same changes as they occur is the emotion.” Whereas for Darwin, our repertoire of emotions is wired into our forty-three facial muscles, for James the topography of emotion maps onto our viscera. Every subjective state, from political rage to spiritual rapture to contentment one feels at the sounds of children playing, is registered in its own distinct “bodily reverberation.”

Lacking experimental evidence, James turned to thought experiments. One of the most illustrative was the following: What would be left of fear or love or embarrassment, or any emotion, if you took away the physiological sensations such as the heart palpitations, trembling, muscle tensions, warmth or coldness in the skin, sweaty palms, and churning of the stomach? James argued that you would be left with a purely intellectual state. Emotional experience is formed in visceral response.

The bodily system most relevant to James’s analysis is the autonomic nervous system, or ANS. The most general function of the ANS is to maintain the internal condition of the body to enable adaptive response to ever-changing environmental events. The autonomic nervous system is like the old furnace in a home: It generates energy and distributes it through the body to support our most basic physical activities—digestion, sexual contact, fight or flight behaviors, and just moving the body through space.

The parasympathetic autonomic nervous system incorporates nerves that originate at the top and near the bottom of the spinal cord. The parasympathetic system decreases heart rate and blood pressure, it facilitates blood flow by dilating certain arteries, it increases blood flow to erectile tissue in the penis and clitoris, and it moves digested food through the gastrointestinal tract. The parasympathetic system also constricts the pupil (for feelings of love, look for smaller rather than larger pupils), and it stimulates the secretion of various fluids in the digestive, salivary, and lachrymal glands (for tears). Scientists believe that the parasympathetic branch of the ANS helps the individual relax and restore resources and bodily function. One branch of the parasympathetic ANS originating near the top of the spinal cord—the vagus nerve—is thought to enable caretaking behavior.

The sympathetic autonomic nervous system (ANS) involves over a dozen different neural pathways originating in the spinal cord, and most typically gets the body moving fast. It increases heart rate, blood pressure, and cardiac output. It produces vasoconstriction in most veins and arteries. It shuts down digestive processes. It is associated with contractions in the reproductive organs that are part of orgasm. And it sends fatty acids into the bloodstream, to provide quick energy to the body. The sympathetic ANS helps prepare the body for fight or flight responses.

James’s thesis—that each distinct subjective emotion is registered in a different bodily reverberation—is anatomically plausible. The different emotions like disgust, embarrassment, compassion, and awe may originate in different patterns of activation in the heart and lungs, the arteries, and the various organs and glands distributed throughout the body. The first rigorous empirical support for James’s claim would arrive 100 years later, in an accidental discovery by Paul Ekman. As Ekman toiled away in his laboratory developing the Facial Action Coding System, he noticed something strange. As he moved the different facial muscles to record how they changed the appearance of his face, the different eyebrow positions, nose wrinkles, lip retractions, and the like, these actions actually altered how he felt. When he furrowed his brow, for example, his heart seemed to race and his blood pressure seemed to rise. When he wrinkled his nose, opened his mouth, and stuck out his tongue, his heart seemed to slow, and his stomach felt as if it was turning over. This discovery led him to a striking possibility: that movements of emotional facial muscles stimulate activation in the autonomic nervous system.

What followed was a rather strange and controversial study by Ekman and his colleagues Robert Levenson and Wallace Friesen. It was one of the first to test James’s thesis about embodied emotion, using what came to be known as the directed facial action (DFA) task. In this study, participants followed muscle-by-muscle instructions to configure their faces into the six different expressions of the emotions that Ekman had studied in New Guinea. For example, for one expression participants were instructed to:

 

Wrinkle your nose

 

Raise your upper lip

 

Open your mouth and stick out your tongue