Positive emotions such as amusement, interest, and contentment lead people to broaden their repertoires of thoughts and actions, giving rise to exploration, reflection, learning, and relationship-building. Over time these behaviors lead to lasting resources, such as knowledge, coping skill, and supportive relationships. The benefits of positive emotions emerge slowly, but they endure, and help individuals thrive in both good times and bad.
This dissertation presents my work on the broaden-and-build theory of positive emotions, ranging from controlled lab research to a practical, field-tested intervention.
Chapter 2 describes research on positive affect and attentional allocation. Sixty undergraduate participants completed a visual search task either with or without added information. This information could improve future performance but might also be distracting. Only individuals low in positive affect benefited from the information, suggesting that positive affect may interfere with complex divided attention. However, I was not able to find a specific attentional or motivational mechanism, which makes the results difficult to interpret. I discuss advantages of the method used and potential improvements.
In Chapter 3, I analyze daily diary data on positive and negative emotions from 84 undergraduate participants. Mediational analysis suggests that positive emotions predict growth in life satisfaction specifically because they also predict growth in trait resilience. Positive emotions are not just pleasurable; they also help build resources for living well. Negative emotions cannot block these benefits, though positive emotions can neutralize negative emotions' harmful effects.
Chapter 4 describes a two-month controlled trial of a positive emotion intervention, in which 195 working adults (132 completers) were randomized to a seven-week course on loving-kindness meditation or to a waitlist. Meditators experienced increased day-to-day positive emotions, which predicted gains in resources including social support, purpose in life, and physical health. These resources in turn predicted increased life satisfaction and reduced symptoms of depression.
These papers chronicle the maturation of the broaden-and-build theory. It now comprises precise laboratory research, environmentally validated theory-based predictions, and potential for real-life interventions. Although it continues to evolve, it is substantiated enough to become one of the foundational ideas for positive emotions research throughout the social sciences.Ph.D.PsychologyUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/60754/1/macohn_1.pd
