The door is already swinging shut as a flash of horror hits me. Clunk.

There they are, my car keys, dangling from the side of the steering wheel, a few feet away and impossibly out of reach. The chill autumn evening is fading to dark; I’m in a rest stop 150 miles from home; and I’ve just locked my keys in my car. Right now I hate myself so much. Where’s my brain!?

The fact is, though, we all make dumb mistakes from time to time. Hitting “send” instead of “delete”; driving right past the exit you meant to take; calling your wife by your ex-girlfriend’s name. In the moment, you feel as though your brain has been replaced with a particularly uncerebral variety of brick. But it turns out that screwing up is a surprisingly subtle and nuanced phenomenon, one that results not despite our brain’s sophistication but because of it. Psychologists hope that by understanding how our brains go wrong, they can help us avoid snafus in the future.

The critical research began decades ago, when aviation experts began trying to understand the alarming rate of crashes that then plagued the industry. It was clear that a high proportion of the accidents were due not to mechanical failures but to human error. Researchers found that just as machines tend to break in certain specific ways—“failure modes,” as engineers put it—humans also tend to screw up in a limited number of predictable ways. To put it another way, there’s an order to our irrationality.

Our brains, it turns out, are much more like machines than we realize. As we roam around negotiating our world, it feels like we’re rational creatures who consciously control our behavior. But most of our actual behavior is carried out beyond our consciousness. “Human cognition can be divided between those processes that are automatic and those that are controlled,” explains Dr. Matthew Lieberman, a psychologist at the University of California Los Angeles. Controlled processes, like writing a sonnet or planning a trip, take mental effort. Automatic processes tend to feel effortless, so much so we’re often hardly aware of them at all. “You have no problem opening your eyes and simultaneously experiencing all the objects that are in front of you,” Lieberman points out, even though quite a lot of complex processing is needed to achieve this feat. It just feels easy because all the work is being carried out behind the scrim of awareness.

Automatic brain systems govern both instinctive behavior and well-learned habits—anything you can do quickly and easily, such as brushing your teeth, recognizing your name amid the burble of strangers’ conversation, or jumping at the sound of a loud noise. The automatic brain is a powerful engine, speedy and efficient. But there’s a trade-off for all that speed. The automatic brain is dumb. When faced with multiple possibilities, it doesn’t reason through its options. Instead, it follows very simple rules of thumb, which psychologists call heuristics. The simplicity of these mental programs makes them lightning fast, but when they encounter something they’re not geared for, it’s like a band saw running into a nail.

One automatic routine I find particularly vexatious involves my ATM card. After years of using the cash machine down the block, my brain has developed a deeply ingrained habit: Swipe my card; put card in wallet; enter PIN; select amount of cash; pocket cash; walk away. Easy and effortless! The problem comes when I visit my parents’ home in Florida. The ATM at the bank closest to their house works a little differently: It’s designed to keep the card until the transaction is done. I swipe the card, but don’t return it to my wallet. The rest of the habit unfolds as always: I get the money, put it in my pocket, and walk away. Ten seconds later, the ATM spits out my card. But I’m not there.

I would have stopped making the mistake if I had learned a new habit for taking money out of that particular ATM. But one of the characteristics of the automatic brain is that it’s slow to learn. In 2009, a team led by psychologist Dr. Phillippa Lally at University College of London recruited volunteers who wanted to teach themselves a new habit, such as eating a piece of fruit every day at breakfast or going for a short jog. Every day the subjects were asked to record whether they’d carried out their tasks or not, and to rate whether a task seemed effortless or even “hard not to do,” as a fully ingrained habit can seem. When the results came in, Lally and her colleagues found most of the volunteers’ self-reports followed a similar pattern: The tasks were hard to do at first, but quickly became much easier, and then reached a plateau as the habit took hold. Getting there took persistence. Depending on the person and the habit they were trying to learn, automaticity took anywhere from 18 days to eight months to set in. Consistency turned out to be key. Those who kept blowing off their tasks were less likely to ever form the habit at all. In my case, I just don’t spend enough time in Florida to form a new pattern of behavior.

Many brain hiccup errors occur in a similar fashion—when the conscious and automatic parts of the brain get in each other’s way. When I forget my wife’s birthday, for instance, it’s not because I don’t love her; it’s because I’ve failed to pre-establish a cue that will trigger my conscious memory. When I miss the exit for my in-laws’ house and instead barrel along as if I’m driving to work—which happens to be two exits down the same highway—again, it’s not for lack of love for my in-laws. (No really!) It’s because distraction prevented me from consciously overriding my well-learned habit of going to the office.

In each case, the solution involves identifying where the automatic brain is going wrong and figuring out a way to interrupt that robotic behavior on your own. In the case of my wife’s birthday, I’ve set up a reminder in my iPhone. To avoid missing my in-laws’ exit, I now explicitly ask my wife to remind me when we’re getting close. (Since she doesn’t drive to my office as much as I do, she doesn’t suffer from the same deep behavioral groove.) And when I’m visiting my parents and need cash, I put my wallet back into a different pocket than usual after inserting the card in the ATM. When I reach the end of the routine, the strange sensation of an empty wallet-pocket cues me that something’s amiss and my conscious brain reengages.

Understanding how our brains make mistakes doesn’t mean we’ll never screw up again. But it should, hopefully, improve the odds that we don’t make the same mistakes too many times in a row.

Illustration by Gianpalo Pagni.

Brain Hiccups The Saturday Evening Post

As scientists find more medical conditions that respond to placebos just as well as to drugs and even surgery, they are gaining a healthy respect for the mind’s amazing ability to heal. Illustration by Shout.

Maybe you have comforted a crying child by kissing her scraped knee to “make it all better”—and seen her tears turn to a smile and the pain recede. Perhaps you’ve stumbled to the medicine cabinet, half-asleep at 2 a.m., taken an acetaminophen for the headache that woke you, felt better—and discovered in the morning that you had actually taken a calcium pill.

Or maybe you took your arthritic knee to a hospital where you were prepped for arthroscopic surgery, wheeled into the operating room, and had a completely fake procedure in which the surgeon made a few incisions but did not remove the cartilage whose deterioration causes osteoarthritis—after which you had less pain and were walking better than you had in years.

Okay, you have probably never experienced the last one. But scores of patients with osteoarthritis of the knee did. They volunteered for one of the more astounding medical studies in recent years, in which researchers performed true arthroscopic surgery on some volunteers, flushing out the joint and removing cartilage, and sham surgery on others. The sham surgery is a form of placebo, an intervention that has no physical effect (inert sugar pills are the best-known placebos). In the groundbreaking study, when patients with osteoarthritis of the knee merely thought they had received arthroscopic surgery the intensity, frequency, and duration of their knee pain diminished as much as in patients who actually received the highly touted $5,000 procedure.

It is tempting to say that “mere thought” or “mere belief” caused these patients to feel and function better, just as the child’s trust in her mother made her knee feel better and our belief that little white pills will relieve a headache made the calcium tablet do so, even though it contained not a speck of headache-fighting medication. But if doctors and scientists have learned one thing about the placebo response or placebo effect, it is this: There is nothing “mere” about how thoughts, beliefs, and the power of the mind affect the body.

As researchers find more and more conditions that respond to placebos, they are gaining new respect for the power of mind. They are also learning how a belief or expectation can travel from the brain to arthritic knees, asthmatic airways, hypertensive blood vessels, and sites of pain. Understanding these mechanisms holds out the promise of tapping the placebo response more systematically, so more illnesses can be treated not with pills and operations (which almost always come with side effects or other risks) but with the power of the mind. “What we believe and expect can significantly influence the outcome of a disease, how much pain we feel, even whether Parkinson’s symptoms diminish,” says neuroscientist Mario Beauregard of the University of Montreal, who examines the brain basis for the placebo response in his 2012 book, Brain Wars.

To investigate placebos, scientists typically take patients with the same condition and give half of them a real treatment and the other half a placebo. Crucially, all the patients believe they are receiving the real treatment. Studies like these have shown that placebos can successfully treat pain and other problems, including angina, asthma, irritable bowel syndrome, hypertension, gastric reflux, psoriasis, anxiety, and depression.

But while anecdotes are not science, it is stories of the placebo response that drive home its awesome power—much more so than reports in dry research papers. Placebos burst into the medical literature in 1955, with an article by Harvard Medical School anesthesiologist Henry Beecher, who had served as a medic in World War II. One day, when his field hospital was running out of morphine, a desperate Beecher had injected some of the suffering soldiers with a saline solution, assuring them that it would vanquish their pain. Miraculously, it did. With that, placebos had entered the medical mainstream as worthy of study and, increasingly, clinical use.

Placebo Power The Saturday Evening Post

Mark McEwen, former TV weatherman for The Early Show on CBS, found out during a flight to Orlando in 2005. He had been dozing, then woke up, feeling odd. “It was like being underwater and trying to swim to the surface,” says McEwen, now 55. “You’re just trying to survive, to make sense of something that is senseless.” He had no clue it was a stroke. Nor apparently did the attendant who helped him off the plane—or the skycap who left McEwen sitting curbside in a wheelchair. McEwen could barely talk, but he did manage to ring his wife’s cell phone and convey a basic message. “Help me. Not good.”

If someone near you, like McEwen, were having a stroke, would you recognize it? Would you know what to do? Stroke is the third leading cause of death in this country—and every 40 seconds on average, someone in the United States suffers one. About 30 percent of strokes 
are mild, resulting in no disability. But the 20 percent that are severe, yet survivable, can be crippling.

“A major stroke can change everything—the ability to speak, to move, to work,” says Dr. Walter Kernan, professor of medicine at Yale University School of Medicine. “It may seem to rob a person of his life without actually taking it.” Fortunately, new therapies are in the works that may help improve outcomes.

Striking Out Against Stroke

The most significant advance is the clot-busting drug, known as tissue plasminogen activator, or tPA, which can help the 85 percent of patients whose strokes are caused by clots in the brain. “Sadly,” says Dr. Ralph Sacco, a neurologist and president-elect of the American Heart Association (of which the American Stroke Association is a division), “only about 5 percent of patients actually get it because they don’t reach the hospital in time or they don’t go to a [hospital certified as a] primary stroke center, which can give it rapidly.” Administered intravenously, it takes time to dissolve a clot, particularly a large one and as neurologists say, “time is brain.” Last year, the AHA revised its guidelines, saying that tPA could be given up to four hours and 30 minutes after the onset of stroke—a significant increase over the previous three-hour window. But sooner remains better.

“The best outcomes are still in patients with small clots who receive tPA in less than 90 minutes,” says Dr. Rishi Gupta of Vanderbilt University Medical Center.

Other technologies are already available at comprehensive stroke centers (a notch above primary stroke centers, which are mainly geared to giving tPA). At the Cleveland Clinic, doctors are using stents to prop open blocked blood vessels during a stroke, as well as two FDA-approved devices to help remove clots. One, the Merci Retriever, works like a miniature corkscrew to pull the clot out. The other, the Penumbra, breaks up a clot with microjets of water, then suctions out the pieces. Both devices require highly skilled specialists, and not every patient is a candidate. “You have to image the brain first to see if functional tissue remains that could benefit from restored blood flow,” says Dr. Irene Katzan, medical director of the stroke program at the Cleveland Clinic.

Refining Recovery

Acute treatment is only the first step in stroke recovery. Fortunately, therapists are getting better results with post-stroke rehabilitation than ever. “We used to say to patients, ‘you have three to six months to improve, and after that you can’t expect a whole lot,’ ” says Dr. Richard Zorowitz, chair of physical medicine and rehabilitation at Johns Hopkins Bayview Medical Center. Now, knowledge about the brain’s ability to rewire itself—a concept called neuroplasticity—has encouraged therapists (and patients) to try longer and harder.

“Thanks to the neuroplasticity of the brain—the ability of the brain cells to rearrange their connections, our brain has more capacity than we ever imagined to rewire itself for greater levels of recovery,” says researcher and stroke survivor Dr. Jill Bolte Taylor (read “Life After Stroke”).

Dr. Steven C. Cramer at the University of California, Irvine, is working with robotic therapy to help restore function as well as investigating two hormones that may encourage stem cells to develop into new neurons, key cells that transmit nerve signals to and from the brain. So far, early results look promising. Meanwhile, Dr. David Simpson at Mount Sinai School of Medicine in New York is using botulinum toxin (Botox) to help reduce the spasms that lead to twisted limbs and abnormal gaits, a frequent result of stroke.

For the most part, rehab consists of hard work—and lots of it. Three hours a day is the rule of thumb. But technologies like Nintendo’s Wii video game console keeps exercises interesting—engaging stroke patients in games such as bowling or tennis to improve balance and shifting of weight.

As for McEwen, he’s back on his feet after 14 months of rehab. Today the former weatherman, who described his experiences in his 2008 book Change in the Weather, is a motivational speaker and spokesperson for the American Stroke Association. The organization’s latest campaign (PowerToEndStroke.org) is directed at people with risk factors for stroke—high blood pressure, diabetes, excess weight, and a history of heart disease. “There are lots of things you can do to lower your risk for stroke,” says McEwen. “Knowledge
 is power.” And it could just save your life.

The Post Investigates: Stroke Advances The Saturday Evening Post