CHAPTER FOUR Consequences of Thought Speed Kaite Yang*, Emily Pronin†,1 *School of Social and Behavioral Sciences, Stockton University, Galloway, NJ, United States †Department of Psychology, and Woodrow Wilson School of Public and International Affairs, Princeton University, Princeton, NJ, United States 1Corresponding author: e-mail address: [email protected] Contents 1. Introduction 168 1.1 The Idea of Thought Speed 169 1.2 Outline for Chapter 170 2. Thought Speed Affects Mood and Emotion 171 2.1 Manic Thinking: An Initial Demonstration 171 2.2 The Speed–Mood Link 174 3. More Consequences of Thought Speed 178 3.1 Fast Thinking Increases Risk-Taking 178 3.2 Fast Thinking Increases Purchasing Interest 181 3.3 Fast Thinking Enhances Creative Insight 185 3.4 Fast Thinking Elevates Self-esteem 189 3.5 Fast Thinking Is Arousing 191 4. Thought Speed and Related Constructs 192 4.1 Speed and Fluency 192 4.2 Speed and Dual Process Theories of Thinking 195 4.3 Speed and Mental Progression 196 5. How Thought Speed Works 197 5.1 The Basic Idea 197 5.2 Dopamine 199 5.3 Embodiment and Entrainment 201 6. Thought Speed and Treatment for Depression 202 6.1 Direct Experimental Tests 203 6.2 Bipolar Disorder 206 7. Methods of Manipulating Thought Speed 207 7.1 Rapidly Presented Stimuli 207 7.2 Speed-Inducing Cognitive Activities 209 7.3 Musical Tempo 209 7.4 Pharmacological and Physiological Alterations 210 7.5 Time Perception 210 # Advances in Experimental Social Psychology, Volume 57 2018 Elsevier Inc. 167 ISSN 0065-2601 All rights reserved. https://doi.org/10.1016/bs.aesp.2017.10.003 168 Kaite Yang and Emily Pronin 8. Some Future Directions for Thought-Speed Research 211 8.1 Thought Speed and Psychophysiology 211 8.2 Thought Speed and Cognition 212 8.3 Thought Speed and Communication 212 9. Conclusion: Thought Speed in the Modern World 213 References 214 Abstract The speed of thinking is a frequently overlooked aspect of mental life. However, the pace of thought is an essential property of thinking, and its consequences have recently begun to be discovered. In this chapter, we review the psychological consequences of accelerated and decelerated thought pace. We begin by examining how the manipu- lation of thought speed alters mood, self-perception, risk-taking, creativity, and arousal. We highlight the energizing, activating, and hedonic effects of fast thinking, and we show how thought-speed effects are independent of thought content, fluency, and goal progress. We describe an adaptive theory of thought speed wherein psychological responses to the acceleration of thinking confer adaptive advantages for confronting novel, urgent, and rapidly changing situations, and engaging in behaviors driven by appetitive motivation. Lastly, we discuss implications of thought speed and its manip- ulation for treatment of mental illness, for design and delivery of communications and messages, and for life in the age of rapid access and exposure to information. 1. INTRODUCTION We may never have met, but there is something I can say about you with complete certainty: Right now, at this very moment, you are thinking. There is no way that you could be reading this without doing it. You prob- ably could go hours or even days without eating, drinking, speaking, or even checking e-mail, but you could not go that long without thinking. Even when your mind wanders to no place special, you are thinking. Even when you try not to think about anything, you are thinking (perhaps about trying not to think). Nothing may be more fundamental to human existence than the ongoing action of the mind. So thought Descartes who, in what is likely the most famous line in the history of philosophy, claimed: “I think, there- fore I am.” Not surprisingly, then, people devote a good deal of attention to the con- tent of their thoughts. They tell others what they think about topics ranging from politics, to reality TV, to where to get a good meatball sandwich. They choose friendships, careers, and vacation destinations after first consulting their thoughts on which choice to make. People even analyze their dreams, Consequences of Thought Speed 169 looking for meaning in thoughts that emerge when they are not controlling them. The research that we review herein, though, speaks to another aspect of thinking—one that has more recently become an avenue for examining the nature of thought. That aspect involves not WHAT we think about, but rather HOW we think about it. In particular, the specific case of our work, and other work related to it, investigates the consequences of not the content of our thoughts but rather the SPEED, or the pace, with which we have those thoughts. It has long been known that thoughts with positive content make people happy compared to thoughts with negative content (e.g., Velten, 1968). Children are taught the old trick, memorialized in the musical The Sound of Music, of trying to alleviate a sad mood by thinking of their “favorite things” (Wise et al., 1965). The past decade of research on thought speed suggests a new trick for alleviating a sad mood: thinking about things really fast. Although Rodgers and Hammerstein did not write about it, thinking fast about favorite things like “raindrops on roses” and “whiskers on kittens” alleviates sadness far better than thinking slowly about those very same things. It is this pair of simple insights, that the pace of thought can be accel- erated and that such accelerations impact mood, that provides the starting point for our investigations of the consequences of thought speed. But before describing this fundamental speed–mood connection, we turn to a brief discussion of the thought-speed concept. 1.1 The Idea of Thought Speed Thought speed in its essence involves the number of thoughts that one is having per unit of time. Until recently, the idea of thought speed came up only rarely in scientific discussions—and was not a variable that was manipulated; consequently, its effects were not measured or known. The idea of thought speed as an important variable is not entirely new, though. In the psychiatric literature, associations between various mental disorders and the speed of thought have long been noted. Individuals experiencing mania, for example, typically exhibit the hallmark symptoms of “racing thoughts” and “flight of ideas” (Hanwella & de Silva, 2011; Mansell & Pedley, 2008). Indeed, this symptom may be even more common than the stereotypic manic symptom of euphoric affect in predicting the onset of a manic episode (Keitner et al., 1996; Mansell & Pedley, 2008; Molnar, Feeney, & Fava, 1988). Individuals suffering from depressive epi- sodes experience the opposite end of the thought-speed spectrum, with their 170 Kaite Yang and Emily Pronin thoughts sometimes slowed to the point of feeling immobilized (Caligiuri & Ellwanger, 2000). Another psychiatric disorder, ADHD or attention-deficit/ hyperactivity disorder, also has been associated with abnormal thought speed, with at least some of those experiencing it having “sluggish cognitive tempo” (Becker, 2013). Thought speed has also sometimes been recognized as a feature or symp- tom of experiences not involving psychiatric disorder. Certain mind-altering drugs, for example, are known to make thoughts race, including stimulant drugs such as cocaine and amphetamines (Asghar, Tanay, Baker, Greenshaw, & Silverstone, 2003; Heilbronner & Meck, 2014; Kirkpatrick et al., 2016; Vollm et al., 2004), as well as more pedestrian drugs such as caf- feine and nicotine (Childs & de Wit, 2006; Durlach, Edmunds, Howard, & Tipper, 2002; Edwards, Wesnes, Warburton, & Gale, 1985; Hinton & Meck, 1996; Smith, 2002; Smit & Rogers, 2000; Warburton & Mancuso, 1998). Also, in everyday life, people experience fluctuations in their thought speed even when mental disorder and drugs are not part of the picture. For example, drinking the first cup of coffee in the morning may be a reaction to the unpleasant feeling that one’s thoughts are too slow. Lying awake at night with a bout of insomnia, one may lament that one’s thoughts will not slow down. On the other hand, when participating in a productive brainstorming session, one may instead delight in the feeling of one’s thoughts racing along. In each of the above examples of fast and slow thought speed, the pace of thought seems to be a symptom of some other condition—whether it be mental illness, drug intake, tiredness, insomnia, or creative excitement. However, we would argue—and have begun to show in our experimental work—that thought speed is important not only as a symptom in psycholog- ical life but also a cause of various aspects of psychological life. By manipu- lating thought speed through controlled experimentation, we demonstrate that the pace of thought has wide-ranging consequences. This research development is particularly important because thought speed is quite ame- nable to alteration—and fluctuates and varies during the course of everyday human experience. 1.2 Outline for Chapter In this chapter, we begin by reviewing basic evidence for a causal link between positive mood and the speed of thinking. From there, we discuss other consequences of thought speed, most notably consequences for self- perception, risk-taking, creativity, and mental health. Following this review, Consequences of Thought Speed 171 we offer a theoretical account to explain why thought speed impacts these various important aspects of psychological life. Finally, we discuss the impor- tance of thought speed in the context of modern life, where the speed of exposure to stimuli—especially digital information and communications— seems to be accelerating more every day. In reviewing this material, we present an inclusive review of conse- quences of thought speed as well as a theoretical framework for those effects. We describe how thought speed, thought content, and behavior covary in predictable patterns.