"Long before it's in the papers"
January 27, 2015


Depressing reverie takes up almost half our waking time, study finds

Nov. 13, 2010
Courtesy of Harvard University
and World Science staff

Peo­ple spend almost half their wak­ing hours think­ing about some­thing oth­er than what they’re do­ing, and this mind-wan­der­ing typ­ic­ally makes them un­hap­py. So con­cludes a study by psy­chol­o­gists Mat­thew A. Kil­lings­worth and Dan­iel T. Gil­bert of Har­vard Uni­vers­ity, re­ported this week in the re­search jour­nal Sci­ence.

“A hu­man mind is a wan­der­ing mind, and a wan­der­ing mind is an un­hap­py mind,” Kil­lings­worth and Gil­bert write in the re­port. “The abil­ity to think about what is not hap­pen­ing is a cog­ni­tive achieve­ment that comes at an emo­tion­al cost.”

Un­like oth­er an­i­mals, as far as we know, hu­mans spend a lot of time think­ing about what is­n’t go­ing on around them: events that hap­pened be­fore, might hap­pen in the fu­ture, or may nev­er hap­pen. In­deed, mind-wan­der­ing seems to be the hu­man brain’s de­fault mode of opera­t­ion, the scient­ists said.

To track this be­hav­ior, Kil­lings­worth de­vel­oped a pro­gram for the Ap­ple iPhone app that con­tacted 2,250 vol­un­teers at ran­dom in­ter­vals to ask how hap­py they were, what they were cur­rently do­ing, and wheth­er they were think­ing about their cur­rent ac­ti­vity or about some­thing else that was pleas­ant, neu­tral, or un­pleas­ant.

Sub­jects could choose from 22 gen­er­al ac­ti­vi­ties, such as walk­ing, eat­ing, shop­ping, and watch­ing tel­e­vi­sion. On av­er­age, re­spon­dents re­ported that their minds were wan­der­ing 46.9 per­cent of time, and no less than 30 per­cent of the time dur­ing eve­ry ac­ti­vity ex­cept mak­ing love.

In all, the study gath­ered 250,000 “data points” on sub­jects’ thoughts, feel­ings, and ac­tions as they went about their lives.

“Mind-wan­der­ing ap­pears ubiq­ui­tous across all ac­ti­vi­ties,” said Kil­lings­worth, a doc­tor­al stu­dent in psy­chol­o­gy at Har­vard. “This study shows that our men­tal lives are per­vad­ed, to a re­mark­a­ble de­gree, by the non­pre­sent.”

Kil­lings­worth and Gil­bert found that peo­ple were hap­pi­est when mak­ing love, ex­er­cis­ing, or en­gag­ing in con­versa­t­ion. They were least hap­py when rest­ing, work­ing, or us­ing a home com­put­er.

“Mind-wan­der­ing is an ex­cel­lent pre­dic­tor of peo­ple’s hap­pi­ness,” Kil­lings­worth said. “In fact, how of­ten our minds leave the pre­s­ent and where they tend to go is a bet­ter pre­dic­tor of our hap­pi­ness than the ac­ti­vi­ties in which we are en­gaged.”

The re­search­ers es­ti­mat­ed that only 4.6 per­cent of a per­son’s hap­pi­ness in a giv­en mo­ment was at­trib­ut­a­ble to the spe­cif­ic ac­ti­vity he or she was do­ing, whe­re­as a per­son’s mind-wan­der­ing sta­tus ac­counted for about 10.8 per­cent of his or her hap­pi­ness.

Time-lag anal­y­ses con­ducted by the re­search­ers sug­gested that their sub­jects’ mind-wan­der­ing was gen­er­ally the cause, not the con­se­quence, of their un­hap­pi­ness.

“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,’” Kil­lings­worth and Gil­bert note in their paper. “These tra­di­tions sug­gest that a wan­der­ing mind is an un­hap­py mind.”

This new re­search, the au­thors say, sug­gests that these tra­di­tions are right.

Killingsworth and Gil­bert’s 2,250 sub­jects in this study ranged in age from 18 to 88, repre­s­enting a wide range of so­ci­o­ec­onomic back­grounds and oc­cupa­t­ions. Sev­en­ty-four per­cent of study par­ti­ci­pants were Amer­i­can.

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People spend 46.9 percent of their waking hours thinking about something other than what they’re doing, and this mind-wandering typically makes them unhappy. So concludes a study by psychologists Matthew A. Killingsworth and Daniel T. Gilbert of Harvard University, reported this week in the research journal Science. “A human mind is a wandering mind, and a wandering mind is an unhappy mind,” Killingsworth and Gilbert write in the report. “The ability to think about what is not happening is a cognitive achievement that comes at an emotional cost.” Unlike other animals, humans spend a lot of time thinking about what isn’t going on around them: contemplating events that happened in the past, might happen in the future, or may never happen at all. Indeed, mind-wandering appears to be the human brain’s default mode of operation. To track this behavior, Killingsworth developed a program for the Apple iPhone app that contacted 2,250 volunteers at random intervals to ask how happy they were, what they were currently doing, and whether they were thinking about their current activity or about something else that was pleasant, neutral, or unpleasant. Subjects could choose from 22 general activities, such as walking, eating, shopping, and watching television. On average, respondents reported that their minds were wandering 46.9 percent of time, and no less than 30 percent of the time during every activity except making love. In all, the study gathered 250,000 “data points” on subjects’ thoughts, feelings, and actions as they went about their lives. “Mind-wandering appears ubiquitous across all activities,” said Killingsworth, a doctoral student in psychology at Harvard. “This study shows that our mental lives are pervaded, to a remarkable degree, by the nonpresent.” Killingsworth and Gilbert found that people were happiest when making love, exercising, or engaging in conversation. They were least happy when resting, working, or using a home computer. “Mind-wandering is an excellent predictor of people’s happiness,” Killingsworth said. “In fact, how often our minds leave the present and where they tend to go is a better predictor of our happiness than the activities in which we are engaged.” The researchers estimated that only 4.6 percent of a person’s happiness in a given moment was attributable to the specific activity he or she was doing, whereas a person’s mind-wandering status accounted for about 10.8 percent of his or her happiness. Time-lag analyses conducted by the researchers suggested that their subjects’ mind-wandering was generally the cause, not the consequence, of their unhappiness. “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,’” Killingsworth and Gilbert note in Science. “These traditions suggest that a wandering mind is an unhappy mind.” This new research, the authors say, suggests that these traditions are right. Killingsworth and Gilbert’s 2,250 subjects in this study ranged in age from 18 to 88, representing a wide range of socioeconomic backgrounds and occupations. Seventy-four percent of study participants were American.