My Plastic Brain

by Caroline Williams

  Taking this view of the brain into account, it doesn’t make sense to try and strengthen particular areas or even the circuits that they are part of. A far more useful thing to do would be to work on flexibly engaging different circuits of the brain based on which is right for the job right now, with the aim of shifting between the best state of mind for the job at hand.

  Here's one example from my recent endeavors. The same brain areas are involved in both sustained focus and in creativity, but they are activated in a different pattern. Sustaining focus involves keeping the frontal bits online to concentrate on the job and allowing the mind to wander occasionally—but not too far. Creativity involves unhooking the frontal control parts for a bit, to let the mind run free, while remembering to bring the focused mind back now and again to check that your ideas are not too bonkers. These two states of mind have a lot in common, but they are also very different, and having access to both of these states requires control over the switch between the two.

  Other areas I have worked on brought similar challenges. Navigation requires the ability to switch from representing a cognitive map in memory, to creating a mental image of yourself in that map, facing in a particular direction. This is a complex bit of computation that involves a huge range of brain areas. Controlling stress and anxiety, too, comes down to being able to switch from a danger-spotting mode into a more relaxed and mindful state, to investigate the situation from a mental and emotional distance. In all of these areas, strength is great, but controlled flexibility is even better.

  It has been slowly dawning on me throughout this project that when you think of it this way, getting override privileges for particular skills and behaviors has less to do with tinkering with particular parts of the machine and more about learning to drive it—if such a thing is possible. And, from my experience this past year or so, it certainly feels like it is.

  This view of mind control owes a lot to a newer wave of neuroscience research that has been ticking away while the rest of us have been buying into the idea that our brains can be trained like a muscle. In recent years, the idea that a particular brain area, or even a group of brain areas, is in charge of complex mental abilities has become a bit old hat—an updated version of phrenology, the nineteenth-century “science” that mapped different mental faculties to specific “organs” in the brain, which could be read via the size of bumps on a person's head.

  As brain-imaging methods have become more sophisticated than head bump reading, though, it has become possible to look not just at the size of certain brain areas or brain activity within them but also at the fibers linking different parts of the brain to others, and the activity running along them. The ultimate plan is to use this information to map large parts of that wiring diagram—the connectome—in human brains and ultimately to link differences in wiring and activity to the variation in behavior and mental ability. We are nowhere near to this yet, but the focus has nevertheless begun to shift away from what different parts of the brain specialize in and toward how activity in the networks that link them fluctuates over time.

  Driving these larger-scale networks deliberately sounds as if it would be even more difficult than finding an exercise that taxes a specific brain muscle. To my mind, though, it actually makes the task easier. As I have been working through my shopping list of brain changes, a handful of linked-up brain areas and the mental states they lead to have kept cropping up. And when I succeeded in making changes, it almost always involved getting into the right “state” for the job—or at least noticing when I’m not in it and doing something about it.

  I’m wary of sticking my neck out too far here for fear of adding to the already bulging back catalogue of “neurobollocks,” but if I had to summarize the mental states that I found were the most useful to have control over, I would say they are as follows:

  Figure 7.1. Mental states for override.

  In my own life, I have gotten into the habit of using this as a framework for understanding and controlling my mental state to get whatever needs to be done, done. If I wake up tired and am finding it difficult to concentrate, I’ll either choose a creative, big-thinking kind of task that morning or, if there is focused work that can’t wait, I’ll go out for a brisk walk with a strong cup of tea and come back to my desk in half an hour. That approach seems to make me relaxed and ready in a way that sitting, staring at the screen, and fighting to focus never has. When friends ask me what my biggest lesson from this experiment has been, I tell them that my main conclusion is “knowing when to say fuck it and go for a walk.” I’m joking when I say this, but only just.

  Similarly, if I notice I’m distracted, I’ll consciously direct my attention onto my thoughts and body to see if there is anything that needs my attention—perhaps an unhelpful undercurrent of fear of failure or a tense jaw that isn’t strictly necessary for thinking or reading. Then I’ll give myself whatever is necessary—a break, a walk, a cup of tea and a biscuit, a pat on the back from reading something I have written before that came out well, anything that will ease off the mental pressure—before directing my attention back to the task at hand. If I’m feeling rushed, or as if the day is getting away from me, I’ll stop and consciously direct my attention to the details of what is around me, until it slows down to normal speed and I feel more in control.

  I’m not saying I’ve morphed into a calm and unflustered productivity machine, but I have to say that, nine times out of ten, thinking about my mental state in this way helps me to feel more in control—as if I am choosing my mental state rather than letting my default state rule me. A case in point: I am writing these words while only two weeks away from my deadline for this book, and I still have a frightening amount to do. But whenever anyone asks how it's going and whether I’m going to meet the deadline, I find myself calmly saying that there's a lot to do, but it's all good; I’m getting there. That's not something I would have said a year ago about a magazine article, let alone a book. When it comes to dealing with stress, something has definitely shifted.

  Whether anything has changed physically in my brain to make this happen, or whether I am using the existing wiring slightly differently, is harder to say. Curious, I contact Martijn van den Heuvel, of Utrecht University, in the Netherlands, to see what he makes of all of this. He is one of the researchers leading the charge to describe how the brain's wiring is organized into networks and how variations in the way that people's networks are set up affect brain function and behavior. What he and his colleagues have discovered fairly recently is that the brain's wiring is organized around twelve highly connected regions, or hubs (six matching pairs, one on each side of the brain), which integrate information from all around the brain as it moves into and out of various mental states. A few networks are described as “rich clubs” because they have more connections to each other than other regions of the brain have. I’m wondering if these hubs and rich club networks relate to the mental states I have been working on, so we connect on Skype for a chat.

  I’m used to being the one asking questions, so it throws me slightly when Martijn starts by asking me whether I feel as if anything has changed in my brain. I put my theory to him that perhaps the size of specific brain regions and the wiring between them probably haven’t changed, but that I think I have learned to engage particular networks more efficiently. I suggest that maybe I haven’t so much changed my brain as change the way I use what was there all along. I burble this out, bite my lip, Kermit-style, and wait for the verdict.

  “I think I can deal with that,” he says, nodding slowly. “But as a biologist, I would argue that also some structural changes would have to be made. Perhaps not at the level we are used to seeing with MRI, but if you would be able to zoom into the individual neurons and the individual synapses, then there still needs to be some sort of chemical or anatomical background to this change.” It's what I was talking to Heidi Johansen-Berg about all those months ago. You wouldn’t be able to see anything in a brain scanner, but if you be
lieve that the brain can change—and there is good evidence that it can from all those animal studies—then something must have happened in there.

  What, exactly, has happened is difficult to say, but it might have something to do with being able to integrate information from different brain areas more efficiently and perhaps with changes in the way that different parts of the brain talk to each other.

  “Many of these properties you mention are to do with a balance between different skills of the brain,” says Martijn. “If we assume that we have different brain regions that all have different functions, there needs to be some kind of continuous negotiation between those skills.”

  So if you imagine a few minutes in the life of a brain, you might start with a resting state, where the default-mode network is the most active, chugging away doing nothing very much. After a while, it will drop off and a local network will come to the fore—maybe you hear something, and the auditory processing parts of the brain become active. If that local network activates one of the hub regions—perhaps part of the salience network, because it is particularly relevant for important noise—the information flows to other hubs. Perhaps it will switch on the visual areas, for example, to look for what the noise means. All of this information feeds into an understanding of what is going on. Then this activity may subside and the default-mode network comes up again. “It is like a consequence of how the brain is wired that you would have this transition from one state to the other. This would be the default state of how the brain works, even if we don’t do anything to influence it,” Martijn says.

  In theory, he agrees, better control over how the brain moves between these states could make all the difference to how life feels and to how efficiently the brain deals with a task. “It's like a recipe: you have some ingredients…a good chef could make a dish out of them, but a Michelin Star chef could cook up something just a little bit better. With that respect, I do think that having your brain be able to combine and link stuff together in a more efficient way would be beneficial for the higher brain functions that you mention.”

  So I don’t seem to be barking up totally the wrong tree with this idea, which is a relief because the other plan—to scan my brain, do an intervention, and then point and marvel at the bigger blob on a second scan—was never going to work. Even if it did, it wouldn’t say much about how my brain was actually working differently afterward. The only way to really watch my brain at work would be to take snapshots of brain activity over time and to watch the fluctuation of the various networks. Studies like this are, in theory, possible, but it is such in the early stages—and activity probably varies so much from person to person that it would be inconclusive even if I had persuaded someone to do it to me.

  Nevertheless, Martijn also agrees with my suggestion that getting into the right state by changing what you are doing should be possible. “It could be that the brain state that you are currently in is not susceptible to reading, but if you go out for a run and you change the state of your brain then you might be slightly more susceptible to reading things. That's the boundaries that you can play with, and you can change your mind-set.”

  That's what I was doing in Boston when Joe and Mike suggested that the way to keep my attention on track was to “embrace the fluctuations,” or cycles of focus and mind-wandering in my brain. Until then, I had assumed that improving my ability to concentrate would involve strengthening the power of my frontal control networks, making them so strong that they could hang on tight to my powers of concentration until I was ready to let them go. Instead, learning to recognize both states and allowing them both to take a turn was the key to better attention control. The only way to learn this was to practice it until the state showed up and then learn what it felt like. Having recognized this state, I now know that it also shows up when I’m swimming or doing yoga—anything that requires concentration, basically, but is also enjoyable and relaxing. Something similar was true for creativity: let the mind wander off the leash for a while, and you will probably come up with more creative ideas. You can bring the mind back to heel later to decide if what it brought back was any good.

  Of course it would be nice if each of the states in figure 7.1 mapped seamlessly onto a diagram of particular brain networks. Unfortunately, as with most things about the brain, it's not that simple. Each “state” or zone is the result of a complex flow of information between many networks, some of them in the brain's well-connected club and some of them on the less connected outskirts. Mindfulness, for example, involves the default-mode network (during mind-wandering), the salience network (noticing that the mind has wandered), and the dorsal attention network (bringing attention back to the present). Each of these networks involves rich-club regions, but they are not exclusively in the rich-club network. The cycling between states just keeps going until something more pressing comes up and takes your attention elsewhere.

  MAKE WAY FOR MINDLESSNESS

  One thing that the hubs do seem to have in common is that they have a lot of contact with the default-mode network. This makes me think that embracing the default-mode network might be a powerful way to drive the brain in general. Recent research by Danielle Bassett and her team at the University of Pennsylvania has found that the central location of the default-mode network and its dense connections with the rest of the brain means that it is the least energy-hungry route from one brain state to another.1 Which suggests that, rather than maligning mind-wandering as a problem state, perhaps it's time to rebrand it as just as important a state as focused attention. Mindfulness may be all the rage at the moment, but Bassett's work suggests that it is at least as important to make room for mindlessness. Without going through a spate of neutral, the brain might get stuck in one gear, and it’ll take a lot more effort to get into another. It confirms my hunch that you can’t be mindful all the time, and even if you could, it might not be the best state for everything that you want your brain to do.

  Allowing what seems like undesirable states to have their say is a theme that is cropping up in other areas of psychology. I recently reported on the mental state of boredom,2 which has only recently begun to attract a lot of attention from psychologists. Unlike distractibility, which is often seen as the curse of the hyper-connected age, boredom is, some researchers say, chronically underused nowadays. We have so many opportunities to distract ourselves from it—TV, smartphones, hilarious cat videos—that we don’t have to suffer it for long. Sandi Mann, a boredom researcher at the University of Lancaster, reckons that this is a bad thing. If we never give ourselves the chance to be bored, we are robbing ourselves of not only much-needed downtime but also the chance to let the mind wander aimlessly, and perhaps creatively.

  Not every scientist who is studying boredom thinks that it should be encouraged—and, personally, I’m not entirely convinced that I need more of it, because, for me, boredom comes with a heavy dose of demotivation, which is anything but creative. But aimlessly mind-wandering, without the negative connotations, definitely has a place in any mental toolbox.

  Anxiety, on the other hand, definitely does not. Stress can be a great motivator in small doses, but when it gets out of control, it is the enemy of the other mental states. All of them. Believe me, I have searched the scientific literature for an upside of chronic anxiety or a generally neurotic personality, and I just can’t find any. There was one recent-ish study that found that the upside of worrying what people think of you is that you can’t possibly be a psychopath,3 but that's not actually one of the many things I was concerned about. And while some claim that anxiety is good if you’re in a dangerous situation (because you’re already primed to spot danger and can react quickly), by and large, it's a huge waste of energy. In my experiments, I found that anxiety was hijacking my focus, creativity, and my ability to think logically, and was playing with my perception of time. Basically, it was interfering with everything I was trying to do.

  Thankfully, given the huge spanner anxiety puts into my mental and cogniti
ve works, I feel this is a mental state that I have under much better control. Brain-wise, since emotional control comes under the umbrella of the prefrontal cortex, I’m guessing that I must have gained better control over the switch that gets me into a better-balanced state of mind. Perhaps the balance of signals from the frontal parts of the brain to the emotional centers has shifted so that the frontal regions have become better at getting their point across. Or perhaps fewer panicked messages are coming through, as a result of the cognitive-bias modification. It's probably a bit of both.

  I’m reminded of a conversation I had with neuroscientist Oliver Robinson, from University College London, while we were both at the 2015 Society for Neuroscience meeting in Chicago. He gave a really interesting presentation about how the circuits that link the amygdala and the prefrontal cortex differ in useful anxiety versus pathological anxiety. The answer: in normal anxiety, the panic circuit is dialed up and down in a useful way. In problem anxiety, it gets stuck in the “on” position.

  Afterward, I asked him which comes first in anxiety: does the amygdala react, and the prefrontal cortex has to then turn it down? Or does the strength of the PFC determine how strongly the amygdala reacts in the first place? Oliver's reply answered a lot of my questions about brain activity—it's a circuit; it doesn’t really start anywhere. Activity is circling around between the two in a push-me-pull-you kind of relationship. If the circuit is always turned up to the max, the activity in both parts of the circuit will be higher. No wonder it's so exhausting.