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Saturday, February 22, 2014

Paul Bloom - The War on Reason

Paul Bloom is the Brooks and Suzanne Ragen Professor of Psychology and Cognitive Science at Yale University. His research explores how children and adults understand the physical and social world, with special focus on morality, religion, fiction, and art. He has published more than a hundred scientific articles in journals such as Science and Nature, and his popular writing has appeared in the New York Times, The New Yorker, The Atlantic Monthly, Slate, Natural History, and many other publications. He has won numerous awards for his research and teaching.

Bloom is the author of Just Babies: The Origins of Good and Evil (2013), as well as How Pleasure Works: The New Science of Why We Like What We Like (2011), Descartes' Baby: How the Science of Child Development Explains What Makes Us Human (2005), and several other books. A selection of popular articles and academic articles can be found here.

In this article for The Atlantic Monthly, Bloom argues against the neuro-reductionist nonsense coming from people like Sam Harris, David Eagleman, Jonathan Haidt (all named directly), and Patricia Churchland (not named).

As regular readers will know, I side with Bloom (and Michael Gazzaniga, and Evan Thompson, and many other non-reductionist neuroscientists).

The War on Reason

Scientists and philosophers argue that human beings are little more than puppets of their biochemistry. Here's why they're wrong.

Paul Bloom | Feb 19 2014


Matt Dorfman

ARISTOTLE'S DEFINITION OF MAN as a rational animal has recently taken quite a beating.

Part of the attack comes from neuroscience. Pretty, multicolored fMRI maps make clear that our mental lives can be observed in the activity of our neurons, and we’ve made considerable progress in reading someone’s thoughts by looking at those maps. It’s clear, too, that damage to the brain can impair the most-intimate aspects of ourselves, such as the capacity to make moral judgments or to inhibit bad actions. To some scholars, the neural basis of mental life suggests that rational deliberation and free choice are illusions. Because our thoughts and actions are the products of our brains, and because what our brains do is determined by the physical state of the world and the laws of physics—perhaps with a dash of quantum randomness in the mix—there seems to be no room for choice. As the author and neuroscientist Sam Harris has put it, we are “biochemical puppets.”

This conception of what it is to be a person fits poorly with our sense of how we live our everyday lives. It certainly feels as though we make choices, as though we’re responsible for our actions. The idea that we’re entirely physical beings also clashes with the age-old idea that body and mind are distinct. Even young children believe themselves and others to be not just physical bodies, subject to physical laws, but also separate conscious entities, unfettered from the material world. Most religious thought has been based on this kind of dualist worldview, as showcased by John Updike in Rabbit at Rest, when Rabbit talks to his friend Charlie about Charlie’s recent surgery:
“Pig valves.” Rabbit tries to hide his revulsion. “Was it terrible? They split your chest open and ran your blood through a machine?”

“Piece of cake. You’re knocked out cold. What’s wrong with running your blood through a machine? What else you think you are, champ?”

A God-made one-of-a-kind with an immortal soul breathed in. A vehicle of grace. A battlefield of good and evil. An apprentice angel …

“You’re just a soft machine,” Charlie maintains.
I bristle at that just, but the evidence is overwhelming that Charlie is right. We are soft machines—amazing machines, but machines nonetheless. Scientists have reached no consensus as to precisely how physical events give rise to conscious experience, but few doubt any longer that our minds and our brains are one and the same.

Another attack on rationality comes from social psychology. Hundreds of studies now show that factors we’re unaware of influence how we think and act. College students who fill out a questionnaire about their political opinions when standing next to a dispenser of hand sanitizer become, at least for a moment, more politically conservative than those standing next to an empty wall. Shoppers walking past a bakery are more likely than other shoppers to make change for a stranger. Subjects favor job applicants whose résumés are presented to them on heavy clipboards. Supposedly egalitarian white people who are under time pressure are more likely to misidentify a tool as a gun after being shown a photo of a black male face.

 
Illustration by Stephen Doyle

In a contemporary, and often unacknowledged, rebooting of Freud, many psychologists have concluded from such findings that unconscious associations and attitudes hold powerful sway over our lives—and that conscious choice is largely superfluous. “It is not clear,” the Baylor College neuroscientist David Eagleman writes, “how much the conscious you—as opposed to the genetic and neural you—gets to do any deciding at all.” The New York University psychologist Jonathan Haidt suggests we should reject the notion that we are in control of our decisions and instead think of the conscious self as a lawyer who, when called upon to defend the actions of a client, mainly provides after-the-fact justifications for decisions that have already been made.

Such statements have produced a powerful backlash. What they represent, many people feel, are efforts at a hostile takeover of the soul: an assault on religious belief, on traditional morality, and on common sense. Derisory terms like neurotrash, brain porn, and (for the British) neurobollocks are often thrown around. Some people, such as the novelist Marilynne Robinson and the writer and critic Leon Wieseltier, argue that science has inappropriately ventured outside its scope and has still failed to capture the rich and transcendent nature of human experience. The author and clinical neuroscientist Raymond Tallis worries that such theories suggest no meaningful gap separates man and beast, a position that he argues, in Aping Mankind, is “not merely intellectually derelict but dangerous.”

For the most part, I’m on the side of the neuroscientists and social psychologists—no surprise, given that I’m a psychologist myself. Work in fields such as computational cognitive science, behavioral genetics, and social neuroscience has yielded great insights about human nature. I do worry, though, that many of my colleagues have radically overstated the implications of their findings. The genetic you and the neural you aren’t alternatives to the conscious you. They are its foundations.

KNOWING THAT WE ARE physical beings doesn’t tell us much. The interesting question is what sort of physical beings we are.

Nobody can deny that we are sometimes biochemical puppets. In 2000, an otherwise normal Virginia man started to collect child pornography and make sexual advances toward his prepubescent stepdaughter. He was sentenced to spend time in a rehabilitation center, only to be expelled for making lewd advances toward staff members and patients. The next step was prison, but the night before he was to be incarcerated, severe headaches sent him to the hospital, where doctors discovered a large tumor on his brain. After they removed it, his sexual obsessions disappeared. Months later, his interest in child pornography returned, and a scan showed that the tumor had come back. Once again it was removed, and once again his obsessions disappeared.

Other examples of biochemical puppetry abound. A pill used to treat Parkinson’s disease can lead to pathological gambling; date-rape drugs can induce a robot-like compliance; sleeping pills can lead to sleep-binging and sleep-driving. These cases—some of which are discussed in detail by David Eagleman in Incognito: The Secret Lives of the Brain (excerpted in the July/August 2011 Atlantic)—intrigue and trouble us because they involve significant actions that are disengaged from the normal mechanisms of conscious deliberation. When the victims are brought back to normal—the drug wears off; the tumor is removed—they feel sincerely that their desires and actions under the influence were alien to them, and fell outside the scope of their will.

For Eagleman, these examples highlight the need for a legal framework and criminal-justice system that can take into account our growing understanding of brain science. What we need, he argues, is “a shift from blame to biology.” This is reasonable enough. It’s hardly neurobollocks to think we should take the existence of a tumor into account when determining criminal responsibility for a sex offense.

But some cases raise thorny questions. Philosophers—and judges and juries—might disagree, for instance, as to whether an adult’s having been horrifically abused as a child can be considered as exculpatory as having a tumor. If the abuse visibly changed a person’s brain and stripped it of its full capacity for deliberation, should that count as a mitigating condition in court? What about individuals, such as certain psychopaths, who appear incapable of empathy and compassion? Should that diminish their responsibility for cruel actions?

Other cases are easier. It’s not hard to see the psychological distinction between the cold-blooded planning of a Mafia hit man and the bizarre actions of a paranoid schizophrenic. As you read this article, your actions are determined by physical law, but unless you have been drugged, or have a gun to your head, or are acting under the influence of a behavior-changing brain tumor, reading it is what you have chosen to do. You have reasons for that choice, and you can decide to stop reading if you want. If you should be doing something else right now—picking up a child at school, say, or standing watch at a security post—your decision to continue reading is something you are morally responsible for.

Some determinists would balk at this. The idea of “choosing” to stop (or choosing anything at all), they suggest, implies a mystical capacity to transcend the physical world. Many people think about choice in terms of this mystical capacity, and I agree with the determinists that they’re wrong. But instead of giving up on the notion of choice, we can clarify it. The deterministic nature of the universe is fully compatible with the existence of conscious deliberation and rational thought—with neural systems that analyze different options, construct logical chains of argument, reason through examples and analogies, and respond to the anticipated consequences of actions, including moral consequences. These processes are at the core of what it means to say that people make choices, and in this regard, the notion that we are responsible for our fates remains intact.

BUT THIS IS WHERE philosophy ends and psychology begins. It might be possible that we are physical beings who can use reason and make choices. But haven’t the psychologists shown us that this is wrong, that reason is an illusion? The sorts of findings I began this article with—about the surprising relationship between bakery smells and altruism, or between the weight of a résumé and how a job candidate is judged—are often taken to show that our everyday thoughts and actions are not subject to conscious control.

This body of research has generated a lot of controversy, and for good reason: some of the findings are fragile, have been enhanced by repeated testing and opportunistic statistical analyses, and are not easily replicated. But some studies have demonstrated robust and statistically significant relationships. Statistically significant, however, doesn’t mean actually significant. Just because something has an effect in a controlled situation doesn’t mean that it’s important in real life. Your impression of a résumé might be subtly affected by its being presented to you on a heavy clipboard, and this tells us something about how we draw inferences from physical experience when making social evaluations. Very interesting stuff. But this doesn’t imply that your real-world judgments of job candidates have much to do with what you’re holding when you make those judgments. What will probably matter much more are such boringly relevant considerations as the candidate’s experience and qualifications.

 
Illustration by Topos Graphics

Sometimes small influences can be important, and sometimes studies really are worth their press releases. It’s relevant that people whose polling places are schools are more likely to vote for sales taxes that will fund education. Or that judges become more likely to deny parole the longer they go without a break. Or that people serve themselves more food when using a large plate. Such effects, even when they’re small, can make a practical difference, especially when they influence votes and justice and health. But their existence doesn’t undermine the idea of a rational and deliberative self. To think otherwise would be like concluding that because salt adds flavor to food, nothing else does.

The same goes for stereotyping. Hundreds of studies have found that individuals, including those who explicitly identify themselves as egalitarian, make assumptions about people based on whether they are men or women, black or white, Asian or Jewish. Such assumptions have real-world consequences. They help determine how employers judge job applications; they motivate young children to interact with some individuals and not others; they influence police officers as they decide whether or not to shoot somebody. These are important findings. But as the Rutgers psychologist Lee Jussim points out in his recent book, Social Perception and Social Reality, these studies don’t mean what many people think they do.

For one thing, we apply stereotypes in a limited way, mainly when judging strangers. When we know someone, we’re far more influenced by facts about that individual than about the categories he or she belongs to. To a striking degree, too, we know what our stereotypes are. Ask people about their stereotypes of gay men, the elderly, or lawyers, say, and what they’ll tell you is likely to align pretty well with what social psychologists have found in their studies of unconscious bias. Furthermore, many stereotypes are accurate. To take one of the most obvious examples: men really are more prone to violence and sexual assault than women are. If you need to quickly judge the threat posed by a stranger standing at the corner of the street you’re about to walk down at night, you’ll probably fall back on this stereotype, consciously and unconsciously. And you’ll be right to do so.

None of this is to defend stereotyping. Strong moral arguments exist for why we should often try to ignore stereotypes or override them. But we shouldn’t assume they represent some irrational quirk of the unconscious mind. In fact, they’re largely the consequence of the mind’s attempt to make a rational decision.

A more general problem with the conclusions that people draw from the social-psychological research has to do with which studies get done, which papers get published, and which findings get known. Everybody loves nonintuitive findings, so researchers are motivated to explore the strange and nonrational ways in which the mind works. It’s striking to discover that when assigning punishment to criminals, people are influenced by factors they consciously believe to be irrelevant, such as how the attractive criminals are, and the color of their skin. This finding will get published in the top journals, and might make its way into the Science section of The New York Times. But nobody will care if you discover that people’s feelings about punishments are influenced by the severity of the crimes or the criminals’ past record. This is just common sense.

Whether this bias in what people find interesting is reasonable is a topic for another day. What’s important to remember is that some scholars and journalists fall into the trap of thinking that what they see in journals provides a representative picture of how we think and act.

OUR CAPACITY for rational thought emerges in the most-fundamental aspects of life. When you’re thirsty, you don’t just squirm in your seat at the mercy of unconscious impulses and environmental inputs. You make a plan and execute it. You get up, find a glass, walk to the sink, turn on the tap. These aren’t acts of genius, you haven’t discovered the Higgs boson, but still, this sort of mundane planning is beyond the capacity of any computer, which is why we don’t yet have robot servants. Making it through a single day requires the formulation and initiation of complex multistage plans, in a world that’s unforgiving of mistakes (try driving your car on an empty tank, or going to work without pants). The broader project of holding together relationships and managing a job or career requires extraordinary cognitive skills.

If you doubt the power of reason, consider the lives of those who have less of it. We take care of the intellectually disabled and brain-damaged because they cannot take care of themselves; we don’t let toddlers cook hot meals; and we don’t allow drunk people to drive cars or pilot planes. Like many other countries, the United States has age restrictions for driving, military service, voting, and drinking, and even higher age restrictions for becoming president, all under the assumption that certain core capacities, like wisdom and self-control, take time to mature.

Many commentators believe that we overemphasize reason’s importance. Social psychology, David Brooks writes in The Social Animal, “reminds us of the relative importance of emotion over pure reason, social connections over individual choice, character over IQ.” Malcolm Gladwell, for his part, argues in Outliers for the irrelevance of a high IQ. “If I had magical powers,” he says, “and offered to raise your IQ by 30 points, you’d say yes—right?” But then he goes on to say that you shouldn’t bother, because after you pass a certain basic threshold, IQ really doesn’t make any difference.

Brooks and Gladwell are both interested in the determinants of success. Brooks focuses on emotional and social skills, and Gladwell on the role of contingent factors, such as who your family is and where and when you were born. Both are right in assuming these factors to be significant, and Gladwell is probably correct that IQ, like other human traits, follows the law of diminishing returns. But both are wrong to doubt the central importance of intelligence. Indeed, intelligence, as measured by an IQ test, is correlated with all sorts of good things, such as steady job performance, staying out of prison, and being in a stable and fulfilling relationship. One might object that IQ is meaningful only because our society is obsessed with it. In the United States, after all, getting into a good university depends to a large extent on how well you do on the SAT, which is basically an IQ test. (The correlation between a person’s score on the SAT and on the standard IQ test is very high.) If we gave out slots at top universities to candidates with red hair, we would quickly live in a world in which being a redhead correlated with high income, elevated status, and other positive outcomes.

Still, the relationship between IQ and success is hardly arbitrary, and it’s no accident that universities take such tests so seriously. They reveal abilities such as mental speed and the capacity for abstract thought, and it’s not hard to see how these abilities aid intellectual pursuits. Indeed, high intelligence is not only related to success; it’s also related to kindness. Highly intelligent people commit fewer violent crimes (holding other things, such as income, constant) and are more cooperative, perhaps because intelligence allows one to appreciate the benefits of long-term coordination and to consider the perspectives of others.

Then there’s self-control. This can be seen as the purest embodiment of rationality, in that it reflects the working of a brain system (embedded in the frontal lobe, the part of the brain that lies behind the forehead) that restrains our impulsive, irrational, or emotive desires. In classic studies of self-control that he conducted in the 1960s, Walter Mischel investigated whether children could refrain from eating one marshmallow now to get two later. What he found was that the kids who waited for two marshmallows did better in school and on their SATs as adolescents, and ended up with better self-esteem, mental health, relationship quality, and income as adults. In his recent book, The Better Angels of Our Nature, Steven Pinker notes that a high level of self-control benefits not just individuals but also society. Europe, he writes, witnessed a thirtyfold drop in its homicide rate between the medieval and modern periods, and this, he argues, had much to do with the change from a culture of honor to a culture of dignity, which prizes restraint.

WHAT ABOUT THE capacity for moral judgment? In much of social psychology, morality is seen as the paradigm case of insidious irrationality. Whatever role our intellect might play in other domains, it seems largely irrelevant when it comes to our sense of right and wrong. Many people will tell you that flag burning, the eating of a deceased pet, and consensual sex between adult siblings are wrong, but when pressed to explain why, they suffer what Jonathan Haidt has described as “moral dumbfounding.” They flail around trying to find reasons, which suggests it’s not the reasons themselves that guided their judgments, but their gut intuition.

But as I argue in my book Just Babies, the existence of moral dumbfounding is less damning that it might seem. It is not the rule. People are not at a loss when asked why drunk driving is wrong, or why a company shouldn’t pay a woman less than a man for the same job, or why you should hold the door open for someone on crutches. We can easily justify these views by referring to fundamental concerns about harm, equity, and kindness. Moreover, when faced with difficult problems, we think about them—we mull, deliberate, argue. I’m thinking here not so much about grand questions such as abortion, capital punishment, just war, and so on, but rather about the problems of everyday life. Is it right to cross a picket line? Should I give money to the homeless man in front of the bookstore? Was it appropriate for our friend to start dating so soon after her husband died? What do I do about the colleague who is apparently not intending to pay me back the money she owes me?

Such rumination matters. If our moral attitudes are entirely the result of nonrational factors, such as gut feelings and the absorption of cultural norms, they should either be stable or randomly drift over time, like skirt lengths or the widths of ties. They shouldn’t show systematic change over human history. But they do. As the Princeton philosopher Peter Singer has put it, the moral circle has expanded: our attitudes about the rights of women, homosexuals, and racial minorities have all shifted toward inclusiveness.

Regardless of whether or not one views this as moral progress (some nihilists and cultural relativists think there is no such thing), it does suggest a cumulative evolution. People come to moral conclusions, often through debate and consultation with others, and these conclusions form the foundation for further progress. Just as modern evolutionary theory builds on the work of Darwin, our moral understanding builds on the moral discoveries of others, such as the wrongness of slavery and sexism.

WE'RE AT OUR WORST when it comes to politics. This helps explain why recent attacks on rationality have captured the imagination of the scientific community and the public at large. Politics forces us to confront those who disagree with us, and we’re not naturally inclined to see those on the other side of an issue as rational beings. Why, for instance, do so many Republicans think Obama’s health-care plan violates the Constitution? Writing in The New Yorker in June 2012, Ezra Klein used the research of Haidt and others to argue that Republicans despise the plan on political, not rational, grounds. Initially, he notes, they objected to what the Democrats had to offer out of a kind of tribal sense of loyalty. Only once they had established that position did they turn to reason to try to justify their views.

But notice that Klein doesn’t reach for a social-psychology journal when articulating why he and his Democratic allies are so confident that Obamacare is constitutional. He’s not inclined to understand his own perspective as the product of reflexive loyalty to the ideology of his own group. This lack of interest in the source of one’s views is typical. Because most academics are politically left of center, they generally use their theories of irrationality to explain the beliefs of the politically right of center. They like to explore how psychological biases shape the decisions people make to support Republicans, reject affirmative-action policies, and disapprove of homosexuality. But they don’t spend much time investigating how such biases might shape their own decisions to support Democrats, endorse affirmative action, and approve of gay marriage.

None of this is to say that Klein is mistaken. Irrational processes do exist, and they can ground political and moral decisions; sometimes the right explanation is groupthink or cognitive dissonance or prejudice. Irrationality is unlikely to be perfectly proportioned across political parties, and it’s possible, as the journalist Chris Mooney and others have suggested, that the part of the population that chose Obama in the most recent presidential election is more reasonable than the almost equal part that chose Romney.

But even if this were so, it would tell us little about the human condition. Most of us know nothing about constitutional law, so it’s hardly surprising that we take sides in the Obamacare debate the way we root for the Red Sox or the Yankees. Loyalty to the team is what matters. A set of experiments run by the Stanford psychologist Geoffrey Cohen illustrates this principle perfectly. Subjects were told about a proposed welfare program, which was described as being endorsed by either Republicans or Democrats, and were asked whether they approved of it. Some subjects were told about an extremely generous program, others about an extremely stingy program, but this made little difference. What mattered was party: Democrats approved of the Democratic program, and Republicans, the Republican program. When asked to justify their decision, however, participants insisted that party considerations were irrelevant; they felt they were responding to the program’s objective merits. This appears to be the norm. The Brown psychologist Steven Sloman and his colleagues have found that when people are called upon to justify their political positions, even those that they feel strongly about, many are unable to point to specifics. For instance, many people who claim to believe deeply in cap and trade or a flat tax have little idea what these policies actually mean.

So, yes, if you want to see people at their worst, press them on the details of those complex political issues that correspond to political identity and that cleave the country almost perfectly in half. But if this sort of irrational dogmatism reflected how our minds generally work, we wouldn’t even make it out of bed each morning. Such scattered and selected instances of irrationality shouldn’t cloud our view of the rational foundations of our everyday life. That would be like saying the most interesting thing about medicine isn’t the discovery of antibiotics and anesthesia, or the construction of large-scale programs for the distribution of health care, but the fact that people sometimes forget to take their pills.

Reason underlies much of what matters in the world, including the uniquely human project of reshaping our environment to achieve higher goals. Consider again our racial and gender stereotypes. Many people believe that circumstances exist in which it is wrong to use these stereotypes when making judgments. If we are worried about this, we can act. We can use reason to invent procedures that undermine our explicit and implicit biases. Blind reviewing and blind auditions block judges from using stereotypes, even unconsciously, by shielding them from information about candidates’ race or sex or anything else other than the merits of what one is supposed to be judging. Quota systems and diversity requirements take the opposite tack, and are rooted in different intuitions about the morally right thing to do; they enforce representation by minority groups, thereby taking the decision out of the hands of individuals with their own preferences and agendas and biases.

This is how moral progress happens. We don’t become better merely through good intentions and force of will, just as we don’t usually lose weight or give up smoking merely by wanting to. We use our intelligence. We establish laws, create social institutions, write constitutions, and evolve customs. We manage information and constrain options, allowing our better selves to overcome those gut feelings and appetites that we believe we would be better off without. Yes, we are physical beings, and yes, we are continually swayed by factors beyond our control. But as Aristotle recognized long ago, what’s so interesting about us is our capacity for reason, which reigns over all. If you miss this, you miss almost everything that matters.

~ Paul Bloom is a professor of psychology and cognitive science at Yale University, and the author of Just Babies: The Origins of Good and Evil (2013).

The Doors: Live in Denmark & Los Angeles (1968) - Jim Morrison Near His Charismatic Peak


Via Open Culture, the curators of cool on the interwebs.

The Doors Play Live in Denmark & LA in 1968: See Jim Morrison Near His Charismatic Peak


Open Culture | February 21st, 2014


Do they look a bit scruffy, the Doors on live Danish TV in 1968? My image of the Doors is forever colored by Oliver Stone’s The Doors. But the real Jim Morrison had even better hair than his doppelgänger Val Kilmer (“not a case of casting,” quoth Ebert, “but of possession”), even if the above performance is less Lizard King than lounge lizard. John Densmore lays back on the beat, gets out the way of Morrison’s free associative poetry. Guitarist Robbie Krieger riffs intently, looks subdued. Always the one to watch, the recently departed Ray Manzarek plays hypnotic baselines with his left hand while his right dances around melodic blue note phrases. It’s a very cool show, but the lack of an audience is palpable.



Morrison was at his best, and probably also worst, before crowds of admirers. He has no lack of them in another ’68 performance, this time at the Hollywood Bowl. Where the Danish gig is cabaret, this is a shamanistic happening: Morrison wears something like a sleeveless toreador’s jacket and the band plays loud, especially Densmore, who bashes his drums like John Bonham. Jim Morrison seems entranced, and really stoned. Densmore later said he’d just dropped acid: “I could tell once we hit the stage because his movements, his performance, was a little deliberate; a little like he was holding it together. But he was fantastic.”
The Hollywood Bowl is the show to see. It was a magical night. It was a big deal to play the Hollywood Bowl. We were all so excited. We’d had dinner with Mick Jagger just before the show and he was right in the front. For any fan of The Doors — young or old — this is really the way it was; this is the way to see what it was all about.
In neither of these concerts is Morrison quite the unhinged maniac of legend, but things, as they say, had already begun to unravel. Two years later the band would play its last show with Morrison at The Warehouse in December of 1970. Some believe the Doors peaked in 1967 and never topped their debut (a “stoned, immaculate classic” and the dark underbelly of Sgt. Pepper’s sunny psychedelia). I don’t buy that at all. But even if these shows catch them on the start of a decline, it was a long slow burn, and beautiful to watch.

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Josh Jones is a writer and musician based in Durham, NC. Follow him at @jdmagness

Friday, February 21, 2014

Quantum Entanglement Animated


Here is a little science fun for your Friday, from Open Culture, of course, the curators of cool on the internets.

Quantum Entanglement Animated

February 20th, 2014


PhD Comics has released the third video in an animated series explaining Quantum concepts and devices. This one focuses on Quantum Entanglement and features the work of Caltech physicists Jeff Kimble and Chen-Lung Hung. Meanwhile Jorge Cham, creator of PhD Comics, provides the accompanying animation.

Entire courses on Quantum Entanglement can be found in our collection of Free Online Physics Courses, part of our collection of 825 Free Online Courses.

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The Era of the Wandering Mind? Twenty-First Century Research on Self-Generated Mental Activity


From Frontiers in Psychology: Perception Science, this is an interesting literature on the topic of self-generated mental activity and mind wandering (one and the same). Their analyses demonstrates a dramatic increase in the term “mind wandering” from 2006, with a corresponding and significant cross-over of psychological investigations of mind wandering into cognitive neuroscience (particularly in relation to research on the default mode and default mode network).

The era of the wandering mind? Twenty-first century research on self-generated mental activity

Felicity Callard [1], Jonathan Smallwood [2], Johannes Golchert [3], and Daniel S. Margulies [3]
1. Centre for Medical Humanities and Department of Geography, Durham University, Durham, UK
2. Department of Social Neuroscience, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany
3. Max Planck Research Group: Neuroanatomy and Connectivity, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany

The first decade of the twenty-first century was characterized by renewed scientific interest in self-generated mental activity (activity largely generated by the individual, rather than in direct response to experimenters’ instructions or specific external sensory inputs). To understand this renewal of interest, we interrogated the peer-reviewed literature from 2003 to 2012 (i) to explore recent changes in use of terms for self-generated mental activity; (ii) to investigate changes in the topics on which mind wandering research, specifically, focuses; and (iii) to visualize co-citation communities amongst researchers working on self-generated mental activity. Our analyses demonstrated that there has been a dramatic increase in the term “mind wandering” from 2006, and a significant crossing-over of psychological investigations of mind wandering into cognitive neuroscience (particularly in relation to research on the default mode and default mode network). If our article concludes that this might, indeed, be the “era of the wandering mind,” it also calls for more explicit reflection to be given by researchers in this field to the terms they use, the topics and brain regions they focus on, and the research literatures that they implicitly foreground or ignore.


Introduction: A New Era of Mind Wandering Research?


One fundamental feature of the human mind is that mental activity does not cease when the mind is unoccupied by external demands. Instead, we often have thoughts and feelings that are unrelated to events in the here and now – a capacity that depends upon our mind’s ability to self-generate both cognitive and affective phenomena independently of environmental input (Smallwood, 2013). Throughout the article, we use the term “self-generated mental activity” to describe the fact that such experiences are largely generated by the individual, rather than occurring in direct response to experimenters’ instructions or to specific external sensory inputs. We use this term to describe an overarching category that encompasses a variety of phenomena – including mind wandering, daydreaming, fantasy, task-unrelated thought, and stimulus-independent thought (SIT). It should be noted that these phenomena do not exactly map on to one another (for example, self-generated mental activity would include deliberate problem-solving, and would also include daydreaming and mind-wandering, which may incorporate non-volitional processes). Despite this heterogeneity, the term “self-generated mental activity” captures a common phenomenon: that associated conscious experience is relatively more dependent on the individual’s concerns, preoccupations and hopes (i.e., self-generated), rather than immediate perceptual input (i.e., perceptually generated).

The number of studies in this special Research Topic (“Toward a psychological and neuroscientific account of the wandering mind”), coupled with the variety of topics they address, make clear that there is currently significant scientific interest in self-generated mental activity. This was not necessarily predictable: even a decade ago, investigations of these experiences were relegated to the backwaters of psychological research (see Smallwood and Schooler, 2006 for a discussion). Indeed, psychologically oriented research on self-generated mental activity was hampered for much of the twentieth century, because of the powerful influence that behaviorism exerted for many decades (e.g., Watson, 1913 and Skinner, 1953; for reflections, see Callard et al., 2012). From the 1940s to the 1970s, researchers in the field perceived that topics involving self-generated mental activity were not greeted at all positively by many senior psychologists: the field was still dominated by the pervasive meta-theory bequeathed by Watson and Skinner, which resulted in the exclusive legitimacy of behaviorist methodologies in many departments and many peer-reviewed journals (Klinger, personal communication, 2013). Nonetheless, pioneering and still influential psychological research was conducted by a small number of researchers during these decades – in particular the path-breaking research on daydreaming by Jerome Singer and his doctoral students John Antrobus and Kenneth Pope (e.g., Singer and Antrobus, 1965; Antrobus, 1968; Pope and Singer, 1978; Singer and Pope, 1978), and subsequent research by Klinger (1971), as well as by, e.g., Giambra (1974, 1993). This research was frequently not published in the most prestigious psychology journals, and often appeared in monographs (e.g., Singer, 1966, 1975) or in smaller or speciality journals (e.g., Perceptual and Motor Skills (e.g., Singer and Antrobus, 1963) and Imagination, Cognition and Personality).

Those early works undoubtedly provided the foundations upon which isolated researchers continued to work in the late twentieth century (e.g., Einstein and McDaniel, 1997; Wegner, 1997). In this article we focus on the first decade of the twenty-first century – that moment during which research on self-generated mental activity moved out of the shadows, towards the scientific mainstream, and increasingly into journals with greater apparent scientific credibility. In contrast to earlier, widespread dismissal of or lack of interest in self-generated mental activity, many researchers now acknowledge that these phenomena have broad implications for many elements of psychological and neural function. For example, research has focused on how self-generated thought might be related to both physical (Epel et al., 2013) and mental health (Killingsworth and Gilbert, 2010); explored its implications for attentional control (Smallwood and Schooler, 2006; McVay and Kane, 2009; McVay et al., 2009; Smallwood, 2010); considered its implications for educational success (Smallwood et al., 2007a); and addressed its relation to psychiatric conditions such as depression (Smallwood et al., 2005, 2007c, 2009). A further strand of research has begun to illuminate how mind wandering is related to the nature and functions of intrinsic changes in brain activity (Mason et al., 2007; Smallwood et al., 2008; Christoff et al., 2009; Kam et al., 2011; Smallwood et al., 2013b). High-profile and/or highly cited publications in Science (Mason et al., 2007; Killingsworth and Gilbert, 2010) Proceedings of the National Academy of Sciences (PNAS; Christoff et al., 2009; Szpunar et al., 2013) and the British Medical Journal (Galera et al., 2012) make it likely that this trend will continue.

Prior to our research for this article, our sense was that “mind wandering” is now the dominant term used by researchers to characterize the self-generated mental activity in which they are interested. However, the history of psychology and proximate disciplines indicates a broader palette of terms relating to self-generated mental activity (e.g., fantasy, daydreaming; Callard et al., 2012). We were intrigued, therefore, by: (i) whether the term “mind wandering” currently does dominate research on self-generated mental activity; (ii) if it does dominate, when and how it came to do so; (iii) whether research on mind wandering, specifically, is closely related to research on other, analogous phenomena and experiences; and (iv) whether mind wandering research tends to focus on particular psychological phenomena and processes, and on particular brain functions.

Our previous research has highlighted the benefits of explicit reflection on emergent scientific fields. We have emphasized the value of analysing how certain assumptions can become (prematurely) embedded; how certain terms and concepts can become solidified over others; how normative claims (explicit or implicit) can be made about the phenomena under investigation; and how distinct bodies of research with different terminologies and ontological foundations can be brought together (or kept apart; Callard and Margulies, 2011; Callard et al., 2012; Margulies et al., 2013). This article combines our scientific and historical interests in self-generated mental activity with an exploration of how recent peer-reviewed research has described such experiences. We combine bibliometric analyses with our own expertise in the history and current state of research on self-generated mental activity. Our hope is to encourage reflection on these issues by other scientists who are building understanding of how the mind self-generates conscious experience. One central aim is to bring analytical visibility to the fact that Frontiers in 2013 has a special topic on the wandering mind, rather than, for example, on SITs, task-unrelated thoughts (TUTs) or self-generated cognition.


Methods and Results


We wished to investigate three different aspects of recent peer-reviewed literature that address self-generated mental activity: (i) temporal changes in a subset of terminologies used to describe self-generated mental activity; (ii) the particular research topics (e.g., particular psychological processes and/or brain functions) that characterize research currently being conducted on what we expected to be the most common category of self-generated experience: mind wandering; and (iii) where there is cross-fertilization of research interests and findings within the wide field of research on self-generated mental activity, and where there is compartmentalization of research that remains separated from other research arenas.

We determined that a combination of methods would allow us to address these three areas of inquiry: (i) we used quantitative and qualitative methods descriptively to explore recent historical changes in the use of terms for self-generated mental activity, and in the topics on which researchers investigating self-generated mental activity focus; and (ii) we performed a bibliometric analysis and visualized a citation and terminology map of the literature.


Descriptive Analysis of Terminology for Self-Generated Mental Activity


Historical Changes in Terminology to Describe Self-Generated Mental Activity
We searched the ISI Web of Science database in March 2013 in order to plot changes in terminologies used to encompass self-generated mental activity. We used our own expertise regarding historical and current research on mind wandering and related phenomena to identify the terms under which to search (these comprised: daydreaming, mind wandering, SIT, TUT, spontaneous cognition, spontaneous thought, and fantasy proneness). We then assembled a database of all articles that cited the three most highly cited articles for each of the terms. We did this because using the terms themselves would have restricted the pool of articles by a terminology, rather than investigating the pool of literature to which articles using those terms were contributing. We restricted our search to the decade prior to this special research topic in Frontiers (i.e., 2003–2012). This is a relatively short time span; however, it covers precisely that point at which we were aware that there appeared to be substantially growing interest on the part of psychologically oriented research communities in self-generated mental activity. The number of publications yielded by this procedure was then plotted over time (in relation to whether each of the original terms appeared in the title and/or abstract and/or keyword of each item in the database; Figure 1).
FIGURE 1  
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FIGURE 1. Changes in the frequency of citations across the ten years prior to 2013. It is apparent that the term mind wandering has seen a rapid increase in the frequency of papers using this term over this period. By contrast, some research that uses other, related terms has remained at a relatively consistent level over the same period. The x-axis describes the year the paper was published. The y-axis describes the number of papers published in each year that have the term in the title, abstract, or keywords. Different colored lines describe the different terms used to describe self-generated mental activity.
What is particularly noticeable is the difference between those terms that hover at roughly the same level throughout the decade (e.g., fantasy proneness and spontaneous cognition) and those that become increasingly prominent (daydreaming, SIT and – particularly noticeably – mind wandering). Indeed, in 2010, there is a step-change in the prominence of research that uses the term mind wandering. (Mind wandering, noticeably, does not feature until 2006, subsequent to which it very closely tracks daydreaming until the divergence in 2010 precipitated by the much larger increase in mind wandering than in daydreaming.)

Changes in Research Focus within Literatures Addressing Mind Wandering

Data from the Section “Historical changes in terminology to describe self-generated mental activity” revealed the recent and growing dominance of research using the term mind wandering. In order to interrogate this literature more closely, we investigated changes in the use of keywords in the mind wandering articles (i.e., those articles in the database using “mind wandering” in the title, abstract or keywords) to understand any changes in research focus that have accompanied the rapid growth of interest in mind wandering.

As the number of papers was relatively small (n = 145), and the number of keywords was relatively large (approximately 900), we reduced these terms into superordinate categories (which were based on the substantial experience of one of the authors, Jonathan Smallwood, in mind wandering research). This was performed simply to reduce the number of categories to a manageable number. Based on an analysis of the distribution of these keywords, Jonathan Smallwood identified a broad set of categories of research (n = 15) that accounted for a large percentage of the terms used. These categories were selected on the basis of the distribution of keywords identified and largely served to reduce pseudonyms (e.g., the terms “default mode” and “default mode network” were collapsed into a single category) and to create meaningful psychological categories (e.g., recollection and working memory were collapsed into a category of memory processes). Some of these categories were labeled using categories introduced during the process (e.g., the keywords “resting state,” “gray matter,” “prefrontal cortex,” etc. were all grouped within the category “cognitive neuroscience”). A second rater (Johannes Golchert) independently assessed the same data using the set of categories produced by Jonathan Smallwood. We interrogated these data using descriptive statistics. Although these ratings were reliable, we make no claims that they reflect a definitive set of research categories; they simply serve to provide a smaller number of categories with which we can explore broad changes in recent research on mind wandering.

We were then interested in exploring two themes. First, in order to identify the large categories of research that are associated with mind wandering over the last decade, we plotted the relative proportion of each of the categories in our sample in the form of a pie chart (Figure 2). The largest category of keyword associated with papers that used the term mind wandering was the term cognitive neuroscience, which occurred over 25% of the time (and in which the subsection “default mode network” represented a significant proportion). The next largest sets of categories were: memory processes, attention and perception and performance. Notably, therefore, approximately 25% of the key words found in our sample were related to aspects of behavior that mind wandering has been shown to derail.
FIGURE 2  
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FIGURE 2. Pie chart illustrating the different categories that form the focus of mind wandering research papers over the last decade. The categories were identified by one author (Jonathan Smallwood), and were derived from papers’ keywords. Their applicability was confirmed by an independent assessment of these categories by a second author (Johannes Golchert). Agreement between authors was high.
Our second aim was to consider historical trends that occurred in the use of key words over the last decade. We plotted the number of papers on mind wandering falling within each of our identified categories each year over the period of interest (Figure 3A). Given that the category of cognitive neuroscience accounted for over a quarter of our data, we plotted the historical trend in this category, and in one of its largest subcomponents, the default mode network, separately from all other keywords (Figure 3B). It can be seen that certain keywords show a pattern of slow and steady growth and are present in the majority of the years covered by our study (for example, SIT/TUT). Others have shown a rapid increase in their prevalence; of these, some were not present in the initial period (such as control), and others (such as consciousness) emerged concurrently with the turn to “mind wandering” in 2006. What is particularly noticeable is the predominance of cognitive neuroscientific research in the last 2 years of the selected period (2010–2012); within this same short time span, the visibility of research specifically on the default mode/default mode network is also striking.
FIGURE 3  
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FIGURE 3. Changes in the categories that form the focus of mind wandering research papers between 2003 and 2012. It can be seen that almost half of the citations refer to psychological phenomena (A) whereas approximately the same amount refer to research focusing on cognitive neuroscience and in particular the default mode network (B).

Visualization of Research Literatures and Co-Citation Networks

The methods used above allowed us to gain a preliminary understanding of the rise of particular terminologies over the last decade, as well as the topics of enquiry being focused on within the mind wandering literature. We were also keen to have a greater understanding of the use of different terms employed in the field, the specific shifts that have occurred in the form of novel domains of investigation, and which communities cite – or do not cite – each other’s research. CiteSpace is a software tool that has been developed to map various aspects of citation networks, including the evolution of a literature over time (Chen, 2004, 2006). Based on databases of the scientific literature, it provides a flexible and interactive interface for assessing numerous aspects of the dynamics within a given field. For example, of relevance to the current analysis, CiteSpace enables the user to slice a database of literature into years of publication, and then to assess similarity of articles based on the similarity of referenced citations. Terms can also be culled from titles, keywords, and abstracts to depict their proximity based on shared inclusion in articles. The visualization platform then allows links between references or terms to depict the first year in which a connection occurred using colored edges. Subsequent usage of a term or reference can then be visualized using concentric colors that represent the frequency of citation (or use) for each year. While CiteSpace provides numerous further analytic possibilities, we constrained our analyses here (depicted in Figure 4) to the two analyses described above to facilitate interpretability.
FIGURE 4
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FIGURE 4. CiteSpace was used to visualize the literature from 2003 to 2012 presented in Figure 1. The colors represent years, the squares are highly used terms (top), and the circular nodes are cited articles (bottom). Each colored circle represents the number of citations/uses during that year. Edge links between nodes represent co-occurrence (in the case of terms) and co-citation (in the case of articles), with the color representing the first year in which the connection was found.
The network visualization presented in Figure 4 provides information about the organization of the citation network and use of terms over the past decade (2003–2012) using the database procedure described for the Section “Historical changes in terminology to describe self-generated mental activity” (and presented in Figure 1). CiteSpace deals with the problem of substantial inconsistencies in the number of articles per year by including only the most relevant, which are determined by their number of citations. The top 1% of cited articles (with a maximum of 100) from each year were included in the similarity calculations, which were based on co-citations and common term use. The proximity of nodes in the graph represents this similarity, and the visualization also reveals specific terms with high frequency of use (Figure 4, top) and articles with high accumulation of citations (Figure 4, bottom; represented by node size, where color subdivides frequency by year). The colored edges represent the earliest year in which the connection was found.

The network visualization renders immediately clear the emergence of a new tightly clustered research field beginning in 2006–2007 (green colored edges) that is characterized by terms such as “default mode network” and “functional connectivity” (Figure 4, top). “Stimulus-independent thought” falls at the edge of this cluster, closer to the psychological literature from which it emerged, though still in close proximity to the cognitive neuroscience cluster. “Working memory” is situated as a bridge between this more recent field shift toward cognitive neuroscience, and a distinct cluster described by “fantasy proneness.” On the other side of this cluster (i.e., at a distance from the cognitive neuroscience cluster) lie a circle of related terms that tie together dissociation, hypnotic susceptibility, imaginative involvement and mystical experiences. Most recently, the term “sustained attention” emerges in a tight orange cluster from 2011 from the cognitive neuroimaging literature, suggesting the emergence of a novel field of interest in self-generated mental activity.

The cited references tell another aspect of the story, indicating the role certain articles may have played in providing links between various fields. For example, Smallwood and Schooler (2006), which was published in a major psychology journal, lies right at the heart of the cognitive neuroscience cluster, depicting the central role of that article in the emerging link between “default mode” and mind wandering that has characterized the second half of the last decade. (Notably, most of the highly cited cognitive neuroscience publications (Figure 4, bottom) address the default mode and/or default mode network, e.g., Shulman et al., 1997; Gusnard et al., 2001; Raichle et al., 2001; Greicius et al., 2003; Fox et al., 2005; Buckner et al., 2008). Meanwhile in the cluster that includes fantasy proneness, dissociation and hypnotic susceptibility, the Tellegen Absorption Scale (Tellegen and Atkinson, 1974) has overwhelming significance, which extends across the entire period under investigation.


Discussion


Our analyses revealed several important features of recent research on self-generated mental activity. First, there are a number of distinct terminologies and topics of research, and these are subject to differential historical changes in terms of the frequency with which they are used. Certain terms and research topics (those associated with SIT, task-unrelated thought, and mind wandering) have grown in stature over the last decade. Our initial conjecture vis-à-vis the growing prominence of the specific term mind wandering is upheld: the last decade has not only seen an increase in research on mind wandering, but has also been marked by a solidification of the use of this term over and above alternatives.

The specific term “mind wandering” becomes prominent only very recently; prior to that, it was terms such as daydreaming and task-unrelated thought that were more dominant. Indeed, it is conceivable that a paper published in 2002 by Schooler in the high-profile Trends in Cognitive Sciences, which focused on dissociations between experience and meta-consciousness, and which used the phrase “catching one’s mind wandering” in the abstract, helped to facilitate a shift towards the scientific community’s use of the term “mind wandering.” (Prior to 2002, there are few uses of “mind wandering” in the psychological literature; though see, amongst others, Giambra, 1989, which operationalized “daydreaming/mind wandering” through task-unrelated thoughts, and Einstein and McDaniel, 1997, which appears to be the first to use “mind wandering” in the title). In the decades prior to those we have focused on here, the most prominent psychological research on self-generated mental activity – carried out largely by Singer, Antrobus, Klinger and Giambra – privileged constructs and phenomena that included daydreams/daydreaming, fantasy and TUTs. It is possible to advance hypotheses about why the term mind wandering superseded some of these terms. For example, the construct “fantasy” could well have been regarded (by both contemporary cognitive psychologists and cognitive neuroscientists) as too closely associated with psychoanalytically inspired research, which was increasingly jettisoned from mainstream psychology as the twentieth-century proceeded. Nonetheless, more research needs to be done to more thoroughly understand why certain terms have been overtaken by others.

The rise in “mind wandering” research has been aided by its translation from cognitive psychology into cognitive neuroscience in the last half decade. Here, it has a close tie to research on the default mode network and functional connectivity. These are, notably, research fields that, like the term “mind wandering,” came to visibility in the twenty-first century (Callard and Margulies, 2011; indeed, it could be said that the mind wandering field and the resting state/default mode network fields appear to act as motors for one another – each raising new questions for the other field to answer, and each drawing interested researchers into one another’s orbit). The close link between mind wandering research and research on the default mode network arguably implies a one-to-one mapping between a kind of experience and a particular brain network, which is likely not doing justice to the varieties of self-generated mental activity, nor to the complexity of the neural processes that contribute to these heterogeneous states. Indeed, we have argued that this tight association between mind wandering and the default mode network is at least in part owing to its historical context. That cognition has been understood largely in relation to action and environmental influences meant that “mind wandering” (as the apparent opposite of such cognition) became bound to the activation of the so-called task-negative network (the default mode network). We have argued that “this apparent ‘see-sawing’ of neural activity between two widespread brain networks suggest(s) rather intuitive – and folk-psychological – distinctions between opposing psychological functions of goal-oriented cognition and spontaneous thought” (Callard et al., 2012).

We also found that certain key articles have acted to bring together psychological and neuroscientific perspectives on self-generated mental activity. For example, in 2006 Smallwood and Schooler published “The restless mind”; while this article did not use mind wandering in its title, it did have mind wandering as a keyword, and also contained the sentence: “By referring to this phenomenon as mind wandering, a term familiar to the lay person, we hope to elevate the status of this research into mainstream psychological thinking.” A year later, Mason et al. (2007) published their high-profile Science article: its title brought together mind wandering, the default mode and SIT. This continued in 2008–2010 through the publication of articles by Buckner et al. (2008), Christoff et al. (2009), and Andrews-Hanna et al. (2010), which further cemented the links between the default network and mind wandering. In 2009, Schooler and Kane, each of whom has published well-known and highly cited research on mind wandering, organized a large symposium on “Wandering Minds and Brains” at the annual meeting of the Psychonomics Society in Boston (http://www.psychonomic.org/pdfs/PS_Call_For_Symposia_B.pdf). This symposium is likely to have acted as a stimulus for additional research (and subsequently citations) on mind wandering amongst cognitive psychologists and those in related fields. Mind wandering has also played center stage to at least two commentaries in high profile journals relating to executive control (McVay and Kane, 2010) and its neural basis (Gilbert et al., 2007). In the same vein, Killingsworth and Gilbert (2010) used the term “a wandering mind” in the title of their high-profile 2010 Science publication. Together, this combination of high impact papers and theoretical controversies set the stage for the very rapid growth of research on mind wandering from 2010 onward.

Second, both from our analysis here and our knowledge of the longer history of research that investigates self-generated mental activity, it can be argued that there are a number of relatively discrete research communities that have investigated such activity – often under the umbrella of distinct terms. Figure 4 indicates that this burgeoning interest in self-generated mental activity within cognitive neuroscience has been relatively distinct since the second half of the last decade from significant areas of psychological research that have addressed related processes and phenomena. The lack of relationship between these research communities needs to be understood in part via a longer history in which the concept of “fantasy proneness” was formulated in the 1980s (originally by Wilson and Barber, 1981, 1983). Fantasy proneness is often treated as a trait (cf. mind-wandering, which has also been treated as a trait, e.g., Kane et al., 2007), was shown in certain respects to be correlated with certain psychopathologies, and was in many cases separated out from research on fantasy as process (Klinger et al., 2009). Indeed, researchers working on absorption, fantasy proneness, and dissociation (where much of the focus is on the maladaptive and/or psychopathological) tend to be relatively secluded from cognitive psychologists and cognitive neuroscientists researching mind wandering and daydreaming (where much of the focus is on processes that are commonly regarded as “normal”). This raises many interesting questions about the extent to which each distinct research sub-community might be using different kinds of normative assumptions and conceptual frameworks to understand related phenomena.


Implications


We suggest that the range of terms used to investigate self-generated mental activity raises an important question for future research. The literature is heterogeneous and complex, and more research is needed to understand the conceptual, methodological and phenomenological overlaps between the objects of study being investigated by these different research communities. Certain research topics have gained traction under the umbrella of mind wandering, while others might well take shape in a field focused on the investigation of fantasy or of spontaneous cognition.

Rather than regarding such trends as a passive result of collective research agendas, we contend that it would be valuable to explore the motivations and forces that provide traction for certain terms, constructs, and approaches at particular moments in time. What is to be gained by a field through turning its research toward a previously ignored phenomenon and/or construct? Do certain formulations or terms have more flexibility than others for engendering particular interdisciplinary overlaps and crossings that have recently taken place? What is gained and what is lost when researchers investigating maladaptive and/or psychopathological manifestations of phenomena are separated from other researchers focusing on other manifestations of the same (or related) phenomena, which are frequently assumed to be “normal”? What causes certain terms and formulations to be “overtaken” by others at particular historical moments and by particular scientific communities? And what are the consequences of certain research fields remaining immune to and isolated from other research fields? Would greater cross-fertilization bring new insights into each respective research community? These are all important questions to which the research community needs to devote more attention if it hopes to provide a comprehensive account of self-generated mental activity.

One general question that this line of research raises is which terms we as a discipline should use to describe the phenomena of self-generated mental activity. Terms such as “mind wandering” and “daydreaming” have attracted the attention of writers in high-profile non-peer-reviewed publications (e.g., Jarrett, 2009). Jonah Lehrer published an essay with the normatively explicit title “The virtues of daydreaming” in The New Yorker in 2012 (Lehrer, 2012); John Tierney published “Discovering the Virtues of a Wandering Mind” (Tierney, 2010a) and “When the Mind Wanders, Happiness Also Strays” (Tierney, 2010b) in 2010. These articles disseminated research that has in the last few years become some of the most highly cited in the field (including Killingsworth and Gilbert, 2010, as well as research by Schooler, Smallwood, and Christoff). Such non-peer-reviewed publications, by drawing on long-standing general cultural interest in daydreams and wandering minds, have undoubtedly contributed to building excitement and interest in and outside of the scientific fields. The concept of mind wandering, while highly amenable to public interest, is an umbrella term for many different aspects of cognitive experience, and is relatively poorly specified (cf. research that focuses on specific aspects of self-generated mental activity, e.g., certain properties of the state, such as stimulus dependence). Different theorists are interested in developing accounts of different aspects of self-generated mental activity, and disagreements can arise because theoretical accounts to describe different elements of these experiences are often seen as contradictory, when in fact they need not be (Smallwood, 2013). One important aim for a more comprehensive account of self-generated mental activity is to develop component process accounts of the different elements of the experience.

Our analysis also revealed how much mind wandering research has focused on what self-generated mental activity interrupts. Much mind wandering research is “negatively” driven, because of a focus on the costs of the experience, rather than on exploring the phenomenology of the underlying processes that drive the mind to self-generate experiences. One example is the role that mind wandering plays as a contributory factor to poor concurrent task performance (see for reviews, Smallwood and Schooler, 2006; Smallwood et al., 2007b; Smallwood, 2013). Recently, mind wandering has been drawn into new arenas of research, such as meditation (Mrazek et al., 2012, 2013). This research topic has perhaps developed because of research demonstrating that mind wandering has robust links to unhappiness (Smallwood et al., 2009; Killingsworth and Gilbert, 2010). Although this research is important, there are several aspects of this focus on the costs of mind wandering that are worthy of comment. Although self-generated mental activity can contribute to unhappiness and error, it can also be associated with creativity (Baird et al., 2012), future planning (Baird et al., 2011), and a tendency to make patient, long-term choices (Smallwood et al., 2013a). These are all important cognitive capacities, indicating that self-generated mental activity is associated not only with psychological costs. Given that self-generated mental activity is so common in daily life, and is coupled with both costs and benefits, it seems that a more nuanced view of the experience is warranted (for a discussion see Smallwood and Andrews-Hanna, 2013). Although understanding the costs that mind wandering can have in particular contexts is important, it is worth reflecting on whether this strong focus might have occluded other approaches, which do not start from a position of focusing on what the phenomenon of interest (mind wandering) interrupts or limits. One of the most self-evident facts that phenomena such as mind wandering indicate is how little we understand about how and why human minds engage in self-generated mental activity to the extent that they do.

In conclusion, our analysis highlights important disciplinary and methodological trends that have accompanied research on self-generated mental activity in the early twenty-first century. We hope to have made explicit the complex role that heterogeneous scientific communities (in their relations or non-relations with one another) can have in consolidating particular terms, methods and areas of enquiry in research on self-generated mental activity. Ultimately, such analyses may open up new approaches, as well as new connections between different research communities. If this is, indeed, the “era of the wandering mind,” it is appropriate that explicit reflection be given by mind wandering researchers to the terms they use, the topics and brain regions they focus on, the research literatures they implicitly foreground or ignore, and the research topics in which they do or do not embed their research. Such reflection will, we hope, help to resolve contradictions and impasses that currently hamper research, and accelerate the pace of research on the intriguing puzzle that self-generated mental activity poses to our research communities.

Conflict of Interest Statement

The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

Acknowledgments

Felicity Callard is supported by two Wellcome Trust Strategic Awards to Durham University (WT086049 and WT098455MA). The authors are grateful to the Neuro Bureau and to members of the Department of Social Neuroscience in the Max Planck Institute for Human Cognitive and Brain Sciences for ongoing creative input. The authors are grateful to the two peer reviewers, whose commentaries greatly strengthened the paper – particularly as regards the longer history of research on daydreaming and related phenomena.

Author Contributions

Daniel S. Margulies conceived of the paper; Felicity Callard and Jonathan Smallwood drafted the manuscript with contributions from Johannes Golchert and Daniel S. Margulies; Johannes Golchert and Jonathan Smallwood undertook the bibliographic analyses and ratings of keywords; Daniel S. Margulies conducted the CiteSpace visualization in consultation with Felicity Callard and Jonathan Smallwood. All authors read and approved the final manuscript.


References are available at the Frontiers site.