Brain Pickings

Posts Tagged ‘psychology’

17 JULY, 2013

Sleep and the Teenage Brain


How a seemingly simple change can have a profound effect on everything from academic performance to bullying.

“Sleep is the greatest creative aphrodisiac,” Debbie Millman asserted in her advice on breaking through your creative block. “Sleep deprivation will profoundly affect your creativity, your productivity, and your decision-making,” Arianna Huffington cautioned graduating seniors in her Smith College commencement address on redefining success. And yet, as German chronobiologist Till Roenneberg argued in his fantastic Internal Time: Chronotypes, Social Jet Lag, and Why You’re So Tired — one of the best science books of 2012, and undoubtedly among the best you’ll ever read — teenagers have already endured years of institutionally inflicted sleep deprivation by the time they get to college: there is a tragic disconnect between teens’ circadian givens and our social expectations of them, encapsulated in what is known as the disco hypothesis.

In Dreamland: Adventures in the Strange Science of Sleep (public library) — the fascinating exploration of what happens while you sleep and how it affects your every waking moment, and also among the best science books of 2012David K. Randall makes an empirically striking case for just how profound the impact of sleep-cycle misalignment is on teenagers, not only academically but also socially, psychologically, and emotionally:

Biology’s cruel joke goes something like this: As a teenage body goes through puberty, its circadian rhythm essentially shifts three hours backward. Suddenly, going to bed at nine or ten o’clock at night isn’t just a drag, but close to a biological impossibility. Studies of teenagers around the globe have found that adolescent brains do not start releasing melatonin until around eleven o’clock at night and keep pumping out the hormone well past sunrise. Adults, meanwhile, have little-to-no melatonin in their bodies when they wake up. With all that melatonin surging through their bloodstream, teenagers who are forced to be awake before eight in the morning are often barely alert and want nothing more than to give in to their body’s demands and fall back asleep. Because of the shift in their circadian rhythm, asking a teenager to perform well in a classroom during the early morning is like asking him or her to fly across the country and instantly adjust to the new time zone — and then do the same thing every night, for four years.

Randall points out that those early school start times originated in an era when youths either had a job after school or had to complete chores on the farm, so the schedule was designed to fit everything in; thus, the teenage circadian rhythm has only become problematic in the past century or so. (Even the very term “teenager” was only coined in the 1930s.) But despite dramatic cultural shifts that have since significantly reduced, if not eliminated, those labor-intensive after-school responsibilities and replaced them with recreational activities like athletics, band practice, and art extracurriculars, the biologically unreasonable early class start times have failed to evolve accordingly. The consequences, it turns out, are far graver than mere teen angst directed at the alarm clock or the unfortunate awakening parent:

The lack of sleep affects the teenage brain in similar ways to the adult brain, only more so. Chronic sleep deprivation in adolescents diminishes the brain’s ability to learn new information, and can lead to emotional issues like depression and aggression. Researchers now see sleep problems as a cause, and not a side effect, of teenage depression. In one study by researchers at Columbia University, teens who went to bed at 10 p.m. or earlier were less likely to suffer from depression or suicidal thoughts than those who regularly stayed awake well after midnight.

Randall highlights a radically simple solution proposed by a school in Edina, Minnesota, in the mid-1990s:

Since students who were awake were more likely to learn something than those who were asleep, the board decided to push the high school’s starting time an hour and five minutes later, to 8:30. It was the first time in the nation that a school district changed its schedule to accommodate teenagers’ sleeping habits.

But the response, bespeaking a questionable hierarchy of priorities, wasn’t what the educators expected:

Some parents complained that the new schedule would take time away from after-school sports and school clubs. Others said that they needed their children home to babysit their siblings. Yet the most persistent complaint was that pushing the start time back wouldn’t result in better-rested kids, but the opposite. Critics argued that teenagers would simply use the time to stay up later, compounding the problem and making their parents’ lives yet more difficult.

The school, however, stuck with the plan for the academic year. A researcher assigned to assess how school policies affect students set out to explore the impact of the experiment through extensive interviews with students, parents, coaches, and teachers. A year later, she presented her unambiguous findings:

Despite the fears of some parents, teenagers did in fact spend their extra hour sleeping, and reported that they came to school feeling rested and alert. At the same time, the number of on-campus fights fell, fewer students reported feeling depressed to their counselors, and the dropout rate slowed. Coaches pushed back practice times until later in the afternoon, and participation didn’t suffer.

The results were also quantifiable: The average SAT score for the top 10% of Edina’s students rose from 1288 to 1500 out of 1600 following the implementation of the new schedule. Even the head of the College Board, that institution behind the ominously familiar standardized test, proclaimed the results “truly flabbergasting.”

But perhaps most remarkable of all is the privilege-blindness of the results: After the success in Edina — a wealthy, mostly white suburban school — Minneapolis, where the majority of students come from minority families with income low enough to qualify them for government-subsidized school lunches, pushed its high school start times from 7:15 to 8:40. The results didn’t flounder: Like their suburban counterparts, Minneapolis students’ grades improved, their drop-out rates fell, and they attended first-period classes more regularly. Achieving the same unflinching results despite enormously different socioeconomic variables demonstrated that sleep habits aren’t culturally primed but are deeply biological. The implications of this, Randall writes, extend far beyond the merely academic:

Other districts followed suit, and found effects that sometimes went beyond scholastics. In Lexington, Kentucky, for instance, pushing the starting time back led to a 16 percent reduction in the number of teenage car accidents during a year in which teenage accident rates rose 9 percent for the state as a whole. In Rhode Island, pushing starting times back a half hour resulted in a forty-five-minute increase in the average amount of time that the average student spent sleeping. ‘Our mornings are a whole lot nicer now,’ the lead researcher of the study, whose daughter was a high school student, said at the time.

Allowing children to get additional sleep may help solve the problem of school bullying as well. A 2011 University of Michigan study tracked nearly 350 elementary school children. About a third of the students regularly bullied their classmates. Researchers found that the children with behavioral issues were twice as likely to have excessive daytime sleepiness or to snore, two symptoms of a persistent sleep disorder. Louise O’Brien, an assistant professor of sleep medicine University of Michigan who was part of the research team, argued that “the hypothesis impaired sleep does affect areas of the brain. If that’s disrupted, then emotional regulation and decision-making capabilities are impaired.”

Dreamland is fantastic in its entirety — peruse more of it here and pair it with this indispensable read on how REM sleep helps regulate our negative emotions.

Public domain photographs via Flickr Commons

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15 JULY, 2013

Why Time Slows Down When We’re Afraid, Speeds Up as We Age, and Gets Warped on Vacation


“Time perception matters because it is the experience of time that roots us in our mental reality.”

Given my soft spot for famous diaries, it should come as no surprise that I keep one myself. Perhaps the greatest gift of the practice has been the daily habit of reading what I had written on that day a year earlier; not only is it a remarkable tool of introspection and self-awareness, but it also illustrates that our memory “is never a precise duplicate of the original [but] a continuing act of creation” and how flawed our perception of time is — almost everything that occurred a year ago appears as having taken place either significantly further in the past (“a different lifetime,” I’d often marvel at this time-illusion) or significantly more recently (“this feels like just last month!”). Rather than a personal deficiency of those of us befallen by this tendency, however, it turns out to be a defining feature of how the human mind works, the science of which is at first unsettling, then strangely comforting, and altogether intensely interesting.

That’s precisely what acclaimed BBC broadcaster and psychology writer Claudia Hammond explores in Time Warped: Unlocking the Mysteries of Time Perception (public library) — a fascinating foray into the idea that our experience of time is actively created by our own minds and how these sensations of what neuroscientists and psychologists call “mind time” are created. As disorienting as the concept might seem — after all, we’ve been nursed on the belief that time is one of those few utterly reliable and objective things in life — it is also strangely empowering to think that the very phenomenon depicted as the unforgiving dictator of life is something we might be able to shape and benefit from. Hammond writes:

We construct the experience of time in our minds, so it follows that we are able to change the elements we find troubling — whether it’s trying to stop the years racing past, or speeding up time when we’re stuck in a queue, trying to live more in the present, or working out how long ago we last saw our old friends. Time can be a friend, but it can also be an enemy. The trick is to harness it, whether at home, at work, or even in social policy, and to work in line with our conception of time. Time perception matters because it is the experience of time that roots us in our mental reality. Time is not only at the heart of the way we organize life, but the way we experience it.

Discus chronologicus, a depiction of time by German engraver Christoph Weigel, published in the early 1720s; from Cartographies of Time. (Click for details)

Among the most intriguing illustrations of “mind time” is the incredible elasticity of how we experience time. (“Where is it, this present?,” William James famously wondered. “It has melted in our grasp, fled ere we could touch it, gone in the instant of becoming.”) For instance, Hammond points out, we slow time down when gripped by mortal fear — the cliche about the slow-motion car crash is, in fact, a cognitive reality. This plays out even in situations that aren’t life-or-death per se but are still associated with strong feelings of fear. Hammond points to a study in which people with arachnophobia were asked to look at spiders — the very object of their intense fear — for 45 seconds and they overestimated the elapsed time. The same pattern was observed in novice skydivers, who estimated the duration of their peers’ falls as short, whereas their own, from the same altitude, were deemed longer.

Inversely, time seems to speed up as we get older — a phenomenon of which competing theories have attempted to make light. One, known as the “proportionality theory,” uses pure mathematics, holding that a year feels faster when you’re 40 than when you’re 8 because it only constitutes one fortieth of your life rather than a whole eighth. Among its famous proponents are Vladimir Nabokov and William James. But Hammond remains unconvinced:

The problem with the proportionality theory is that it fails to account for the way we experience time at any one moment. We don’t judge one day in the context of our whole lives. If we did, then for a 40-year-old every single day should flash by because it is less than one fourteen-thousandth of the life they’ve had so far. It should be fleeting and inconsequential, yet if you have nothing to do or an enforced wait at an airport for example, a day at 40 can still feel long and boring and surely longer than a fun day at the seaside packed with adventure for a child. … It ignores attention and emotion, which … can have a considerable impact on time perception.

Another theory suggests that perhaps it is the tempo of life in general that has accelerated, making things from the past appear as slower, including the passage of time itself.

But one definite change does take place with age: As we grow older, we tend to feel like the previous decade elapsed more rapidly, while the earlier decades of our lives seem to have lasted longer. Similarly, we tend to think of events that took place in the past 10 years as having happened more recently than they actually did. (Quick: What year did the devastating Japanese tsunami hit? When did we lose Maurice Sendak?) Conversely, we perceive events that took place more than a decade ago as having happened even longer ago. (When did Princess Diana die? What year was the Chernobyl disaster?) This, Hammond points out, is known as “forward telescoping”:

It is as though time has been compressed and — as if looking through a telescope — things seem closer than they really are. The opposite is called backward or reverse telescoping, also known as time expansion. This is when you guess that events happened longer ago than they really did. This is rare for distant events, but not uncommon for recent weeks.


The most straightforward explanation for it is called the clarity of memory hypothesis, proposed by the psychologist Norman Bradburn in 1987. This is the simple idea that because we know that memories fade over time, we use the clarity of a memory as a guide to its recency. So if a memory seems unclear we assume it happened longer ago.

And yet the brain does keep track of time, even if inaccurately. Hammond explains the factors that come into play with our inner chronometry:

It is clear that however the brain counts time, it has a system that is very flexible. It takes account of [factors like] emotions, absorption, expectations, the demands of a task and even the temperature .The precise sense we are using also makes a difference; an auditory event appears longer than a visual one. Yet somehow the experience of time created by the mind feels very real, so real that we feel we know what to expect from it, and are perpetually surprised whenever it confuses us by warping.

In fact, memory — which is itself a treacherous act of constant transformation with each recollection — is intricately related to this warping process:

We know that time has an impact on memory, but it is also memory that creates and shapes our experience of time. Our perception of the past moulds our experience of time in the present to a greater degree than we might realize. It is memory that creates the peculiar, elastic properties of time. It not only gives us the ability to conjure up a past experience at will, but to reflect on those thoughts through autonoetic consciousness — the sense that we have of ourselves as existing across time — allowing us to re-experience a situation mentally and to step outside those memories to consider their accuracy.

But, curiously, we are most likely to vividly remember experiences we had between the ages of 15 and 25. What the social sciences might simply call “nostalgia” psychologists have termed the “reminiscence bump” and, Hammond argues, it could be the key to why we feel like time speeds up as we get older:

The reminiscence bump involves not only the recall of incidents; we even remember more scenes from the films we saw and the books we read in our late teens and early twenties. … The bump can be broken down even further — the big news events that we remember best tend to have happened earlier in the bump, while our most memorable personal experiences are in the second half.


The key to the reminiscence bump is novelty. The reason we remember our youth so well is that it is a period where we have more new experiences than in our thirties or forties. It’s a time for firsts — first sexual relationships, first jobs, first travel without parents, first experience of living away from home, the first time we get much real choice over the way we spend our days. Novelty has such a strong impact on memory that even within the bump we remember more from the start of each new experience.

Most fascinating of all, however, is the reason the “reminiscence bump” happens in the first place: Hammond argues that because memory and identity are so closely intertwined, it is in those formative years, when we’re constructing our identity and finding our place in the world, that our memory latches onto particularly vivid details in order to use them later in reinforcing that identity. Interestingly, Hammond points out, people who undergo a major transformation of identity later in life — say, changing careers or coming out — tend to experience a second identity bump, which helps them reconcile and consolidate their new identity.

So what makes us date events more accurately? Hammond sums up the research:

You are most likely to remember the timing of an event if it was distinctive, vivid, personally involving and is a tale you have recounted many times since.

But one of the most enchanting instances of time-warping is what Hammond calls the Holiday Paradox — “the contradictory feeling that a good holiday whizzes by, yet feels long when you look back.” (An “American translation” might term it the Vacation Paradox.) Her explanation of its underlying mechanisms is reminiscent of legendary psychologist Daniel Kahneman’s theory of the clash between the “experiencing self” and the “remembering self”. Hammond explains:

The Holiday Paradox is caused by the fact that we view time in our minds in two very different ways — prospectively and retrospectively. Usually these two perspectives match up, but it is in all the circumstances where we remark on the strangeness of time that they don’t.


We constantly use both prospective and retrospective estimation to gauge time’s passing. Usually they are in equilibrium, but notable experiences disturb that equilibrium, sometimes dramatically. This is also the reason we never get used to it, and never will. We will continue to perceive time in two ways and continue to be struck by its strangeness every time we go on holiday.

Like the “reminiscence bump,” the Holiday Paradox has to do with the quality and concentration of new experiences, especially in contrast to familiar daily routines. During ordinary life, time appears to pass at a normal pace, and we use markers like the start of the workday, weekends, and bedtime to assess the rhythm of things. But once we go on vacation, the stimulation of new sights, sounds, and experiences injects a disproportionate amount of novelty that causes these two types of time to misalign. The result is a warped perception of time.

Ultimately, this source of great mystery and frustration also holds the promise of great liberation and empowerment. Hammond concludes:

We will never have total control over this extraordinary dimension. Time will warp and confuse and baffle and entertain however much we learn about its capacities. But the more we learn, the more we can shape it to our will and destiny. We can slow it down or speed it up. We can hold on to the past more securely and predict the future more accurately. Mental time-travel is one of the greatest gifts of the mind. It makes us human, and it makes us special.

Time Warped, a fine addition to these essential reads on time, goes on to explore such philosophically intriguing and practically useful questions as how our internal clocks dictate our lives, what the optimal pace of productivity might be, and why inhabiting life with presence is the only real way to master time. Pair it with this remarkable visual history of humanity’s depictions of time.

Photographs: Public domain images unless otherwise noted

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12 JULY, 2013

Thoreau on Friendship, Sympathy, and Animal Consciousness


“A man [is] commonly a locked-up chest to us, to open whom, unless we have the key of sympathy, will make our hearts bleed.”

What better way to complement Maurice Sendak’s lovely vintage illustrated ode to friendship than with a related reflection from one of modern history’s most beloved thinkers? In The Journal of Henry David Thoreau, 1837-1861 (public library) — which also gave us, for a piece of appropriate meta-irony, Thoreau on why not to quote Thoreau — the beloved transcendentalist, born on July 12, 1817, considers the essence of friendship, what it means to be human, and how inextricably connected we are to our fellow non-human beings, who are just as worthy of our sympathy and respect as our human friends.

On July 13, 1857 — the day after his 40th birthday — Thoreau awakens to a resolution for celebrating capital-F friendship as a centerpiece of the good life:

I sometimes awake in the night and think of friendship and its possibilities, a new life and relation to me, which perhaps I had not experienced for many months. Such transient thoughts have been my nearest approach to realization of it, thoughts which I know of no one to communicate to. I suddenly erect myself in my thoughts, or find myself erected, infinite degrees above the possibility of ordinary endeavors, and see for what grand stakes the game of life may be played. I catch an echo of the great strain of Friendship played somewhere, and feel compensated for months and years of commonplace. It is as if I were serenaded, and the highest and truest compliments were paid me. The universe gives me three cheers. Friendship is the fruit which the year should bear; it lends its fragrance to the flowers, and it is in vain if we get only a large crop of apples without it.

For Thoreau, the essence of friendship was the cultivation of true sympathy. On a “stern, bleak, inhospitable” January day in 1856, with the temperature a cruel “5° at noon and at 4 P.M.,” Thoreau observes a closed pitch pine cone he had gathered three days prior, which had just opened in his chamber. From this seemingly mundane occurrence he extracts a profound meditation on existence and the ties of sympathy, by way of a squirrel — that uncanny gift from translating the minutia of the physical world into timeless wisdom on the metaphysical is the defining characteristic of his journal:

If you would be convinced how differently armed the squirrel is naturally for dealing with pitch pine cones, just try to get one off with your teeth. He who extracts the seeds from a single closed cone with the aid of a knife will be constrained to confess that the squirrel earns his dinner. It is a rugged customer, and will make your fingers bleed. But the squirrel has the key to this conical and spiny chest of many apartments. He sits on a post, vibrating his tail, and twirls it as a plaything.

But so is a man commonly a locked-up chest to us, to open whom, unless we have the key of sympathy, will make our hearts bleed.

In fact, this combined sensitivity to other living beings and exaltation of sympathy as a defining duty of what it means to be human emerges again and again throughout the diary as Thoreau touches on insights predating the modern science of animal consciousness by more than a century. On March 31, 1842, in the last entry before his three-year journal hiatus that ended when Thoreau moved to Walden, he contemplates our interconnectedness with the rest of the living world and the joyous humility that springs from its recognition:

All parts of nature belong to one head, as the curls of a maiden’s hair. How beautifully flow the seasons as one year, and all streams as one ocean!


It is the saddest thought of all, that what we are to others, that we are much more to ourselves, — avaricious, mean, irascible, affected, — we are the victims of these faults. If our pride offends our humble neighbor, much more does it offend ourselves, though our lives are never so private and solitary. How many young finny contemporaries of various character and destiny, form and habits, we have even in this water! And it will not be forgotten by some memory that we were contemporaries. It is of some import. We shall be some time friends, I trust, and know each other better. Distrust is too prevalent now. We are so much alike! have so many faculties in common! I have not yet met with the philosopher who could, in a quite conclusive, undoubtful way, show me the, and, if not the, then how any, difference between man and a fish. We are so much alike! How much could a really tolerant, patient, humane, and truly great and natural man make of them, if he should try? For they are to be understood, surely, as all things else, by no other method than that of sympathy. It is easy to say what they are not to us, i.e., what we are not to them; but what we might and ought to be is another affair.

The Journal of Henry David Thoreau, 1837-1861 is sublime in its entirety, the kind of lifelong companion to be revisited regularly and voraciously for a wholehearted existence.

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