Google changes the brain. Playing computer games changes the brain. Conversing in a compassionate way changes the brain.
If you half expect this ever-lengthening list to eventually include, oh, making matzoh-ball soup changes the brain, you are not alone. It is true that lots of solid scientific studies show that the adult brain can change in response to what we do and the lives we lead. But they are in danger of being crowded out, at least in the public’s understanding, by far less rigorous claims. (The jury is still out on Google, games, and conversation, but we’re pretty sure soup-making won’t make the short list.)
It’s a shame to see something as scientifically significant as neuroplasticity—the ability of the adult brain to change its structure or function in an enduring way—overpopularized to the point that it could start losing its real meaning.
The promise of tapping neuroplasticity to relieve suffering is genuine. From physical therapy that changes part of the brain so it can do the job of another part of the brain that has been devastated by a stroke, to mindfulness-based therapy that quiets the circuit responsible for obsessive-compulsive disorder, techniques using the principle of neuroplasticity are already in use by physicians and therapists. But how far can neuroplasticity go?
Perhaps as far as an emotional reset—harnessing neuroplasticity to change how you respond emotionally to the ups and downs of life. Neurobiologist Richard Davidson of the University of Wisconsin, an expert on the emotional brain, calls it “neurally inspired behavioral therapy.” He is talking about a kind of therapy that identifies the brain activity underlying an emotional trait you wish to change, such as a tendency to dwell in anger, and then targets this brain activity with mental exercises designed to alter it. The result is a healthier “emotional style,” as Davidson calls it.
This mission is still in its infancy, but there are hints that it works. Much of Davidson’s research has focused on determining the patterns of brain activity that characterize facets of our emotional style, such as how well we maintain positive feelings. (Full disclosure: I cowrote Davidson’s 2012 book, The Emotional Life of Your Brain.) People who are a little familiar with brain structure might assume that these patterns occur within the brain’s limbic system, an evolutionarily ancient region that includes the amygdalae, the two almondshaped structures that are responsible for feelings of anxiety and fear.
If these patterns were lodged in this ancient brain region, where our powerful survival instincts emerge from, we would be out of luck. Think of trying to simply will yourself to be happy or sad, or any other emotion, with the brute force of a survivalist. Not so easily done. I don’t know about you, but if I’m feeling miserable and someone tells me to just cheer up on the spot, I want to slug them.
Fortunately, the brain’s emotional circuits are actually connected to its thinking circuits, which are much more accessible to our conscious volition. That has been one of Davidson’s most important discoveries: the “cognitive brain” is also the “emotional brain.” As a result, activity in certain cognitive regions sends signals to the emotion-generating regions. So while you can’t just order yourself to have a particular feeling, you can sort of sneak up on your emotions via your thoughts.
This is easier to understand with examples. Davidson discovered that people who are resilient—able to regain their emotional balance after a setback rather than wallowing in anxiety, anger, depression, or another negative emotion—have strong connections between the left prefrontal cortex (PFC) and the amygdalae. The left PFC sends inhibitory signals to the amygdalae, basically telling them to quiet down. As a result, the negative feelings generated by the amygdalae peter out, and you’re not mired in unhappiness or resentment. In contrast, people with little emotional resilience (including those with depression, who may be shattered by every disappointment) have fewer or weaker signals between the PFC and the amygdalae, due to either low activity in the PFC or poor connections between it and the amygdalae.
Neurally inspired therapy to increase emotional resilience, then, strengthens the left PFC so it sends stronger, longer-lasting inhibitory signals to the amygdalae. One way to do this, Davidson says, is mindfulness meditation, in which you observe your thoughts and feelings with the objectivity of a disinterested, nonjudgmental witness. This form of mental training gives you “the wherewithal to pause, observe how easily the mind can exaggerate the severity of a setback, note that it as an interesting mental process, and resist getting drawn into the abyss,” he told me. As a result, you create stronger connections between the PFC and the amygdalae, and thus fewer persistent feelings of anger, sadness, and the like after an emotional downer.
Another way to strengthen the circuitry that supports emotional resilience is through cognitive reappraisal training, in which you challenge the accuracy of catastrophizing thoughts (“I am days behind in my work; I’m going to get fired”). This “directly engages the prefrontal cortex,” Davidson says, “resulting in increased prefrontal inhibition of the amygdalae.”
Davidson has also discovered that in people whose default mode is a positive frame of mind and a sense of well-being, there is high activity in the left PFC as well as in the nucleus accumbens. This is a structure deep within the brain that is associated with pleasure and a sense of reward and motivation. In contrast, in people with a consistently negative outlook, the nucleus accumbens is quiet and is found to have few connections to the PFC.
As with much of the brain’s emotional apparatus, the nucleus accumbens is not reachable through conscious thought directly; you can’t will it into greater activity. However, Davidson believes you can exploit its connections to the PFC, which is accessible to conscious targeting. The great strength of the PFC is planning, imagining the future, and exercising self-control. By putting yourself in situations that demand forethought, he says, you can strengthen the PFC and thus its ability to goose activity in the nucleus accumbens. You might, for instance, put yourself in a situation where an immediate reward beckons— forbidden food usually works, though anything fun when you’re supposed to be working would also be effective— and resist its siren call.
What are the limits of neuroplasticity? The honest answer is, we don’t know. But when neuroscientists in the past scoffed at the power of the brain to change in meaningful ways, such as to remap the cortex in order to restore mobility after a stroke, they were often proved wrong. One new study even shows that the brain is plastic enough to change in response to cognitive demands that are as new to evolution as the industrial soot that caused moths to evolve gray wing scales. Earlier this year, scientists at Stanford pinpointed the anatomical coordinates of a brain region, a mere one-fifth of an inch across, that handles the sight of numerals. Yes, the brain has specialized real estate to process the likes of 5 and 24. Since “no one is born with the innate ability to recognize numerals,” says Stanford neuroscientist Josef Parvizi, “it’s a dramatic demonstration of our brain circuitry’s capacity to change” in response to education and culture.
If regular exposure to the 2+2s on flash cards, signs for 99¢ specials in store windows, and the other digits in our world is sufficient to cause the brain to develop specialized circuitry, surely we are only in Act 1, Scene 1, of understanding the power of neuroplasticity and how to exploit it.
This article also appeared in the October 2013 issue of Mindful magazine.