A Wandering Mind Is an Unhappy Mind
We developed a smartphone technology to sample people’s ongoing  thoughts, feelings, and actions and found (i) that people                         are thinking about what is NOT happening almost  as often as they are thinking about what is and (ii) found that doing so  typically                         makes them unhappy.
Science 12 November 2010: 
Vol. 330 no. 6006 p. 932 
DOI: 10.1126/science.1192439
 
A Wandering Mind Is an Unhappy Mind
  
Harvard University, Cambridge, MA 02138, USA.  
Abstract
We  developed a smartphone technology to sample people’s ongoing thoughts,  feelings, and actions and found (i) that people are thinking about what  is not happening almost as often as they are thinking about what is and (ii) found that doing so typically makes them unhappy. 
Unlike  other animals, human beings spend a lot of time thinking about what is  not going on around them, contemplating events that happened in the  past, might happen in the future, or will never happen at all. Indeed,  “stimulus-independent thought” or “mind wandering” appears to be the  brain’s default mode of operation (1–3).  Although this ability is a remarkable evolutionary achievement that  allows people to learn, reason, and plan, it may have an emotional cost.  Many philosophical and religious traditions teach that happiness is to  be found by living in the moment, and practitioners are trained to  resist mind wandering and “to be here now.” These traditions suggest  that a wandering mind is an unhappy mind. Are they right?  Laboratory experiments have revealed a great deal about the cognitive and neural bases of mind wandering (3–7),  but little about its emotional consequences in everyday life. The most  reliable method for investigating real-world emotion is experience  sampling, which involves contacting people as they engage in their  everyday activities and asking them to report their thoughts, feelings,  and actions at that moment. Unfortunately, collecting real-time reports  from large numbers of people as they go about their daily lives is so  cumbersome and expensive that experience sampling has rarely been used  to investigate the relationship between mind wandering and happiness and  has always been limited to very small samples (8, 9).  We  solved this problem by developing a Web application for the iPhone  (Apple Incorporated, Cupertino, California), which we used to create an  unusually large database of real-time reports of thoughts, feelings, and  actions of a broad range of people as they went about their daily  activities. The application contacts participants through their iPhones  at random moments during their waking hours, presents them with  questions, and records their answers to a database at www.trackyourhappiness.org.  The database currently contains nearly a quarter of a million samples  from about 5000 people from 83 different countries who range in age from  18 to 88 and who collectively represent every one of 86 major  occupational categories.   To  find out how often people’s minds wander, what topics they wander to,  and how those wanderings affect their happiness, we analyzed samples  from 2250 adults (58.8% male, 73.9% residing in the United States, mean  age of 34 years) who were randomly assigned to answer a happiness  question (“How are you feeling right now?”) answered on a continuous  sliding scale from very bad (0) to very good (100), an activity question  (“What are you doing right now?”) answered by endorsing one or more of  22 activities adapted from the day reconstruction method,  and a mind-wandering question (“Are you thinking about something other  than what you’re currently doing?”) answered with one of four options:  no; yes, something pleasant; yes, something neutral; or yes, something  unpleasant. Our analysis revealed three facts. 
First,  people’s minds wandered frequently, regardless of what they were doing.  Mind wandering occurred in 46.9% of the samples and in at least 30% of  the samples taken during every activity except making love. The  frequency of mind wandering in our real-world sample was considerably  higher than is typically seen in laboratory experiments. Surprisingly,  the nature of people’s activities had only a modest impact on whether  their minds wandered and had almost no impact on the pleasantness of the  topics to which their minds wandered. 
Second,  multilevel regression revealed that people were less happy when their  minds were wandering than when they were not [slope (b) = –8.79, P  < 0.001], and this was true during all activities, including the  least enjoyable. Although people’s minds were more likely to wander to  pleasant topics (42.5% of samples) than to unpleasant topics (26.5% of  samples) or neutral topics (31% of samples), people were no happier when  thinking about pleasant topics than about their current activity (b = –0.52, not significant) and were considerably unhappier when thinking about neutral topics (b = –7.2, P < 0.001) or unpleasant topics (b = –23.9, P < 0.001) than about their current activity. Although negative moods are known to cause mind wandering, time-lag  analyses strongly suggested that mind wandering in our sample was  generally the cause, and not merely the consequence, of unhappiness. 
Fig. 1 
Mean happiness reported during each activity (top) and while mind wandering to unpleasant topics, neutral topics, pleasant topics or not mind wandering (bottom).  Dashed line indicates mean of happiness across all samples. Bubble area  indicates the frequency of occurrence. The largest bubble (“not mind  wandering”) corresponds to 53.1% of the samples, and the smallest bubble (“praying/worshipping/meditating”) corresponds to 0.1% of the samples. 
Third,  what people were thinking was a better predictor of their happiness  than was what they were doing. The nature of people’s activities  explained 4.6% of the within-person variance in happiness and 3.2% of  the between-person variance in happiness, but mind wandering explained  10.8% of within-person variance in happiness and 17.7% of between-person  variance in happiness. The variance explained by mind wandering was  largely independent of the variance explained by the nature of  activities, suggesting that the two were independent influences on  happiness. 
In  conclusion, a human mind is a wandering mind, and a wandering mind is  an unhappy mind. The ability to think about what is not happening is a  cognitive achievement that comes at an emotional cost. 
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