Born to Be Good: The Science of a Meaningful Life

I first encountered the deferential smile: D. Keltner et al., “Teasing in Hierarchical and Intimate Relations,” Journal of Personality and Social Psychology 75 (1998): 1231–47.

Research shows that when workers smile in the service industry: For a review of the role of emotion in the workplace, see M. W. Morris and D. Keltner, “How Emotions Work: An Analysis of the Social Functions of Emotional Expression in Negotiations,” Review of Organizational Behavior 22 (2000): 1–50.

workers experience a problematic disconnect: Arlie R. Hochschild, The Managed Heart: Commercialization of Human Feeling (Berkeley: University of California Press, 1983).

This disconnect has parallels to recent studies by my colleague Ann Kring of schizophrenics: A. M. Kring, S. L. Kerr, A. D. Smith, and J. M. Neale, “Flat Affect in Schizophrenia Does Not Reflect Diminished Subjective Experience of Emotion,” Journal of Abnormal Psychology 102 (1993): 507–17; Kring and Neale, “Do Schizophrenics Show a Disjunctive Relationship among Expressive, Experiential, and Psychophysiological Components of Emotion?” Journal of Abnormal Psychology 105 (1996): 249–57.

the empirical literature on the smile yields similarly paradoxical findings: Keltner et al., “Facial Expression of Emotion,” in Handbook of Affective Sciences, 415–32.

The answer is provided by Paul Ekman, and it involves looking away from the lip corners: Frank, Ekman, and Friesen, “Behavioral Markers and Recognizability of the Smile of Enjoyment,” Journal of Personality and Social Psychology 64 (1993): 83–93.

Duchenne smiles differ morphologically: ibid., 83.

D smiles tend to be associated with activity in the left anterior portion of the frontal lobes: Neuroscientist Richard Davidson has made the persuasive case that positive emotions tend to activate regions of the brain on the left side of the frontal lobes, because these regions enable the individual to approach rewards. Ekman, Davidson, and Friesen, “The Duchenne Smile: Emotional Expression and Brain Physiology II,” Journal of Personality and Social Psychology 58 (1996): 342–53.

When a ten-month-old is approached by his or her mother: Davidson and N. A. Fox, “Frontal Brain Asymmetry Predicts Infants’ Response to Maternal Separation,” Journal of Abnormal Psychology 98 (1989): 127–31.

we interviewed middle-aged adults six months after their deceased spouse had passed away: D. Keltner and G. A. Bonanno, “A Study of Laughter and Dissociation: The Distinct Correlates of Laughter and Smiling During Bereavement,” Journal of Personality and Social Psychology 73 (1997): 687–702.

In Emotions Revealed: Paul Ekman, Emotions Revealed (New York: Owl, 2004).

In the 1980s developmental psychologists: E. Z. Tronick, “Emotions and Emotional Communications in Infants,” American Psychologist 44 (1989): 112–19; Tronick, J. Cohn, and E. Shea, “The Transfer of Affect between Mothers and Infants,” Affective Development in Infancy, ed. T. B. Brazelton and M. W. Yogman (Norwood, NJ: Ablex, 1986); T. Field et al., “Behavior State Matching and Synchrony in Mother-Infant Interactions of Nondepressed Versus Depressed Dyads,” Developmental Psychology 26 (1990): 7–14; Field et al., “Infants of Depressed Mothers Show ‘Depressed’ Behavior Even with Nondepressed Adults,” Child Development 59 (1988): 1569–79.

Friends of depressives: Connie Hammen and Ian Gotlib have done superb work documenting the social costs of depression, how it transmits to others and turns relationships into more complex, and at times less rewarding, endeavors. One likely reason is that depressives give off fewer positive emotional cues, in such behaviors as the smile, laugh, and playful touch. Ian H. Gotlib and Constance L. Hammen, Psychological Aspects of Depression: Toward a Cognitive-Interpersonal Integration (Chichester: Wiley, 1992).

In conversations with individuals who show little positive emotion in the face or voice: For a review of these findings, see Keltner and Kring, “Emotion, Social Function, and Psychopathology.”