The science of pain.
How the body and mind manage pain.
Having one arm heated to a painful temperature, while the other arm is plunged into an icy cold bath, would be an unpleasant experience for most of us. But as Israeli researchers discovered in a recent experiment, it didn’t much bother people accustomed to enduring discomfort.
In the study, published in the journal Pain in 2013, elite triathletes who were subjected to the hot-and-cold treatment reported that they experienced pain, just as a control group of casual exercisers did. But the triathletes, who were accustomed to pushing themselves to extremes in their training and in competitions, rated the pain as lower in intensity and were able to tolerate it longer.
Not only that—they had greater ability than ordinary people to control their reaction to one discomfort while they experienced another.
Why were the triathletes able to shrug off such an unpleasant experience? Had they hardened their bodies through their intense training, or conditioned their minds not to fear pain? The researchers believed that it was a combination of mind and body, working together. As Tel Aviv University physical therapy professor Ruth Defrin explained: "It is very difficult to separate physiology and psychology."
For centuries, philosophers debated about whether your mind and consciousness are part of your body, or whether the two are separate entities. But today, thanks to science, we know that the brain, the organ where your perceptions and thoughts take place, in many ways functions as a unit with the rest of your body. In navigating the daunting complexities of the physical world, your brain and body generally work together pretty effectively. But they don’t always tell the truth to each other. Your brain, which utilizes an array of shortcuts to keep its work load manageable, is capable of deceiving the body into feeling and reacting to things that aren’t there. Similarly, your body is capable of playing tricks upon your brain. In this article, we’ll look at how this continual game of mutual deception works.
Your Body and Brain Work Together — Most of the Time
Mind and body are so closely intertwined, in fact, that they often seemingly operate in unison. In an experiment published in Psychological Science in 2010, for example, University of Waterloo researchers had 15 volunteers read a passage from a book on a computer screen, while a sensor tracked their eye movements. At random intervals, the computer beeped, and the subjects reported whether they were paying attention to what they were reading, or whether their minds were wandering.
The researchers discovered an intriguing phenomenon. When the subjects’ minds drifted from the task, they also blinked at a higher rate. "When you start to mind-wander, you start to gate the information even at the sensory endings—you basically close your eyelid so there's less information coming into the brain," explained cognitive neuroscientist Daniel Smilek, one of the study’s authors.
Your brain, of course, is in control most of the time, but picture it as a driver who finds his or her way by studying a roadmap—in this case, mental maps of the body and its various systems, which it uses to govern movement, sensation and perception. The brain takes in the information provided by your senses, evaluates it, and tells your body what to do.
Most of that decision-making takes place in the prefrontal cortex, or PFC, one of the most highly-evolved parts of our brain. In the course of a day, it makes countless decisions, large and small, from what to eat at lunchtime to when you should step off the curb into the street. Psychologists theorize that to make all those decisions manageable, your brain actually has two decision-making systems, which are separate but closely intertwined. System 1 is a sort of autopilot, which will take in information about a situation and act, based upon a set of rules that are formulated by System 2, the ruminating part of your decision apparatus. System 2 monitors system 1 and can override it if necessary, if System 2 detects that you’re about to make a dangerous mistake. The process works so smoothly and seamlessly that we don’t even notice it is running most of the time.
Your brain, amazingly, actually can tinker with itself and make adjustments in order to be able to perform a physical action more deftly. Harvard University medical researchers have discovered, for example, that subjects who practiced a piano exercise over a five-day period actually began to utilize a greater amount of their motor cortex, the area of the brain’s frontal lobe that controls movement.
In turn, there’s evidence that the rest of your body actually helps your brain to work more effectively. A study by U.S. and Chinese researchers, for example, found that elderly Chinese who practiced Tai Chi, a martial art converted into a slow, gentle exercise regimen, three times a week showed increases in brain volume and performed better in tests of memory and thinking, compared to a control group.
A study published in Frontiers in Human Neuroscience in 2013 found that subjects who rode bicycles four times per week performed better at divergent and convergent thinking—two mental processes involved in creativity—than did subjects who didn’t exercise.
But your brain and body don’t always work together smoothly. Your brain, as we’ve mentioned previously, relies heavily upon ingenious shortcuts to deal with the continual onslaught of sensory data that it has to process. Facial recognition, for example, is an activity that’s long been a crucial part of human existence, and your brain has an entire area, the fusiform gyrus in the temporal lobe, that’s assigned to identifying faces. Your fusiform gyrus does this efficiently by breaking down a person’s face into individual parts and then analyzing them. But to save time, your brain doesn’t bother looking at how each part relates to the other parts. That’s why, in experiments, subjects who are shown an upside-down picture of recognized figures will identify them without noticing that their eyes and mouth have been rearranged, so that they’re actually right-side up.
When your hands have to do unfamiliar, opposite tasks—such as making a gun gesture with your left hand and a hitchhiking sign with your right, and then switching—your overloaded brain may opt not to do both simultaneously. Instead, it will shut down on hand’s movements for a moment in order to perform the other. This phenomenon is called bimanual interference, and you’ve got to put in a lot of practice repetitions to overcome it so that you can play the piano or type on a keyboard. Eventually, though, all those repetitions will deepen your neural pathways, enabling you to routinely perform feats that once would have seemed frustratingly impossible.
How Your Brain Can Be Duplicitous
Your brain has enough power over your body to make it react to things that aren’t actually real. The amygdala, your brain’s early warning system for detecting potential danger, and hypothalamus, a brain area which directs the pituitary and adrenal glands to release of chemicals into your body to arouse the fight-or-flight response, also can give you false alarms. If you’re suddenly confronted by a harmless statue of a six-foot-tall snowman—a scenario you’ll actually see in the "Mind Your Body” episode of Brain Games—it’s likely that your amygdala and hypothalamus will fire up the danger response and your body will unleash all of the physical reactions that you would use to escape a real threat.
Your brain even can create feelings that might not even be generated by your senses, and trick you into believing that they are real. Itchiness, for example, is triggered by a specialized neuron that detects faint stimuli, such as a bug crawling on your leg. But that information actually is interpreted in your brain. If you simply think about a bug crawling on your leg, you’ll feel an itch and the urge to scratch it.
And as we noted at the start of this article, your brain can influence your body to reduce the intensity of pain. In a study published in 2011 in the journal Anesthesiology, Stanford University researchers found that subjects who trained themselves to think distracting thoughts or those who re-evaluated their pain in positive terms reported significantly less discomfort. Brain scans revealed that the subjects utilizing distraction showed increased activity in parts of the brain associated with higher-level thinking, while the others had increased activity in the deep brain structures that process emotion.
Your brain apparently even can influence your reproductive system. In a 2011 study published in the journal Fertility and Sterility, researchers found that in-vitro fertilization patients who learned relaxation and other stress-reduction techniques had a significantly higher pregnancy rate (52 percent) than those who didn’t (20 percent).
Your Body Has a Few Tricks of Its Own
Even though your brain is powerfully persuasive, it’s not as if your body always just goes helplessly along for the ride. Studies of rodents, for example, have revealed that bacteria in the gut can influence neural development, brain chemistry and a wide range of behaviors, including emotions, pain perception and how the brain responds to stress. An imbalance between beneficial and disease-causing bacteria can cause an animal’s behavior to change, making it either bolder or more anxious.
Scientists also have discovered that the body’s position and actions can alter a person’s mood. After experimental subjects were asked to hold a pencil between their lips in a way that compelled them to smile, they actually became happier, suggesting that the facial muscles directly influence emotion. And in a 2003 study by Ohio State University researchers, individuals who were asked to either nod their heads in agreement or shake them in disagreement reported that it influenced their opinions. And a 2012 study by San Francisco State University behavioral scientist Eric Peper found that skipping significantly increased subjects’ energy levels, while walking in a slumped posture—like Charlie Brown on a bad day—depressed their energy levels.
It’s also possible for the body’s sensory systems to trick the mind and rewrite its mental maps. In a study published in PLOS ONE in 2011, Dutch researchers rigged subjects with virtual reality gear that gave them the sensation of having either a giant body or a doll-sized one. The illusion was so effective that subjects actually perceived objects as being different in size and distance from reality—either larger and more distant or smaller and nearer, depending upon whether they were Barbie or Shrek-sized.
And as a 2008 article in Brain Research Bulletin detailed, if you cross your fingers and touch your nose, your fingers can trick your brain into thinking that it’s feeling two separate noses.
- Ventricular Psychosis
- Atrial Arrythmia
- Widow's Disease
- Broken Heart Syndrome
- Answer: Broken Heart Syndrome
- When You Are Hungry
- When You Are Cold
- Right After Eating
- Right After Waking Up
- Answer: Right After Eating
- All of the Above
- Answer: All of the Above
How To Work Through Pain
Four steps to help you push through a challenging moment.
In the "Let’s Get Physical" episode of Brain Games, you learned that your mind is capable of fooling your body, and vice-versa. In particular, as athletes and their coaches have known for a long time, it’s possible to train your mind and body to endure considerable amounts of physical discomfort. A 2013 study, for example, found that triathletes who were subjected to extremes of hot and cold actually reported feeling less pain, as well as tolerating it better than a control group. The ability to withstand pain is a skill that could come in handy, whether you’re struggling to reach the finish line or trying to deal with a migraine headache. Here are a few tips from the experts on how to teach yourself to hurt less.
Laugh at the pain.
A 2013 Swiss study found that people who watched a humorous film could hold their hands in ice water better than a control group that wasn’t amused, and that the pain tolerance lasted for 20 minutes after the chuckles subside. Researchers suspect that laughter is a potent analgesic because it releases endorphins and eases muscle tension.
Breathe and talk to yourself.
Doing breathing exercises to relax your body and giving yourself encouraging feedback both have been shown in studies to reduce discomfort, as Women’s Health writer Camille Noe Pagan explained in a 2011 article. If you’re trying to make it through a session in the dentist’s chair or endure a business meeting while suffering through a headache, inhale through your nose for 10 seconds, while repeating a positive mantra such as "it will get better soon." When you exhale, imagine that you’re pushing the pain out your nostrils.
As a 2011 article from AARP: The Magazine notes, a diet rich in foods such as red grapes and cherries, fish, soy products, and herbs and spices such as ginger and turmeric can help protect you against pain. Red grapes, for example, contain resveratrol, a compound that blocks enzymes that contribute to tissue degeneration, including cartilage damage that causes back pain.
Play a sport.
A 2012 meta-analysis of pain studies found that while athletes generally have higher pain tolerance than sedentary people, the amount of pain tolerance varies. Athletes in endurance sports had a fairly consistent moderate tolerance for pain, the most stoic jocks were the ones who played "game" sports. If you’ve ever made the winning shot in a pickup basketball game on a twisted ankle, you know how firing up the competitive urge can help you to block out discomfort.
"Language is such a powerful lens for shaping reality that we frequently forget that it is a tool at all, and take it for reality." R Doyle
15 feb 2014