Chapter 1Baby Neuroscientist’s First Reality CheckI can still vividly remember the first time I had to completely reevaluate the landscape of my work in neuroscience. This happened just over a decade after first hearing my dad’s reminder of how little we all truly know. My journey in between involved a fair amount of luck and indecision, but also an ever-increasing curiosity about how to understand and impact human health.
It was now the summer of 2014. I was just nine months into my PhD studies when I attended a scientific conference with some of the biggest names in my new field. While I’d made early inroads into at least two other careers (medicine and athletic performance coaching), I knew very little about cutting-edge neuroscience.
On the first day of the conference, we heard a talk that referenced a scientific paper with the catchy title “1,026 Experimental Treatments in Acute Stroke.” The essence of the paper is this: At the time it was written (now more than twenty years ago), there were over a thousand treatments that could dramatically decrease the injury caused by a stroke. In rats. But none of these treatments, with the exception of thrombolysis (clot busting), which has been used in humans since the 1950s, have improved outcomes in human stroke patients.
For days afterwards, I couldn’t get this study out of my head. If decades of research and billions of dollars had been invested in the search for better stroke treatments, and literally nothing that worked in the lab had successfully worked in humans, why should we expect the next decades and next billion dollars to have a different result?
This situation is unfortunately not unique to strokes. When it comes to almost every brain injury or neurodegenerative condition, the last major breakthrough in treatment occurred several decades ago. Or, in the case of age-related cognitive decline and dementias such as Alzheimer’s disease, no breakthrough has occurred at all. During the conference, I couldn’t shake the feeling that there was something missing in how we research the brain as we look for ways to treat or support it. And since that day, there is one question that I have continued to reflect on as I’ve built my career as a professor and neuroscientist: What if we’re thinking about the brain all wrong?
The Current State of the BrainBefore we delve into a little neuroscience to understand what we do and don’t know about the brain, and how that applies to our own brains, I think it would be useful to start with a discussion of brain health. Because ultimately, that’s what we are all striving to improve.
Most simply, a healthy brain is one that performs the (cognitive) functions you want, at the time you want it to perform them.
Obviously, my simple definition of brain health has to be applied within the reality of our individual experiences. For example, as much as I would love for my brain to suddenly allow me to clear a dance floor with jaw-dropping breakdancing moves, that’s not going to happen. Anyone who has seen me strut my stuff at an after-hours neuroscience conference disco will gladly attest as much. But, as somebody who has lived and worked in many countries, I might reasonably expect my brain to understand and speak one of the languages I’ve learned, even when I’m under pressure or haven’t slept well.
Brain health, therefore, is incredibly personal. What I want my brain to do could be very different from what you want yours to do, especially as we age. As we’ll see later, this information can help us tailor the skills and tasks we engage our brains in. Of course, there are also common functions that we all want our brains to perform: remember day-to-day occurrences and conversations, sustain focus on specific tasks that are important to us, process a wide range of information, and make decisions in a calm and timely manner. Luckily, the factors that help us achieve our individual goals of brain health and cognition also support these more general components of daily brain function.
There’s one final piece to my definition of a healthy brain that’s critically important—the element of time. In addition to supporting our cognitive function right now, I believe a healthy brain should be as future-proof as possible. This means minimizing the effects of aging on the brain and making sure we’re able to function in, and adapt to, unknown future situations for decades to come. Unfortunately, at least right now, that’s not necessarily the future that our brains can expect.
It’s undeniable that we as a society appear to be at a critical moment when it comes to our collective mental and cognitive health. Everywhere we look, it seems that our brains are increasingly under duress. The sheer volume of information we’re expected to handle—unthinkable to previous generations—keeps increasing, and we’re fracturing our attention by moving from one cognitive task to another much more frequently than we did even twenty years ago. Among the generations who grew up with smartphones and social media as part of their daily lives, more women are receiving prescriptions of antidepressant medications than ever before, and men have a higher-than-ever risk of dying by suicide. At the same time, one in nine American adults over forty-five says they’ve noticed worsening cognitive function, and more than one in ten adults over sixty-five has dementia. In the next fifteen to twenty years, the burden of dementia is expected to at least double, if not triple, worldwide, becoming either the first or second most common cause of death in most high-income countries by 2040.
Phew. Deep breath.
When contemplating statistics like these, it’s not surprising that the default feeling is one of helplessness. In the face of this palpable sense that our brains are collectively struggling, we then layer on a coating of inevitability. We assume that there’s nothing we can do to change the state or trajectory of our brain health, and that decline is unavoidable. But, while not all these issues have simple solutions, and we should never pretend that’s the case, there’s plenty of evidence to suggest that these statistics can be a call to action rather than a reason to despair.
Perhaps because we believe there’s nothing we can do to help or change its fate, the brain often doesn’t get the attention it should. Even those of us who are interested in reading books about health tend to focus externally, and mostly below the neck. This is partly because we’ve been taught to think that the way we look in the mirror is a direct expression of our overall health (which is often not true at all), and partly because the brain remains a mystery—its skills and functionality hard to decipher and measure.
The story of how our brains function (or not) as they age is a familiar one. Early in life, our cognitive potential seems limitless. We marvel at the ability of children to learn languages and the remarkable capacity of the adolescent brain to effortlessly master an ever-increasing suite of complex modern technology. Looking back at your own young brain, you’ll no doubt fondly remember a time when you were blessed with sharp wits and instant recall. Back then, you were the proverbial young owl from the preface—able to immediately adapt to the strange new world you saw through prism glasses.
Fast-forward to the present day, though, and you tell yourself that you just can’t learn or focus like you used to. Everything “upstairs” feels like much more of a struggle. It may even seem like you’re doomed to experience an unending, unstoppable, unforgiving road to cognitive decline and dementia. And if you ever take time to ponder what you can do about all this, it’s usually to worry about how you’re making it worse—a few more brain cells killed every time you have a bad night of sleep or drink a few too many cocktails (figure 1).
It amazes and saddens me to think that we’ve passed the first quarter of the twenty-first century and still have this fixed (and slightly morbid) view of how our brain function will change over time. On almost a daily basis I talk to scientists, physicians, science journalists, clients, and members of the public who believe we have very little control over our cognitive faculties, especially later in life. But what if I told you that this story we tell ourselves is more fiction than fact? The truth is that, while cognitive function does tend to change over time, and we can’t prevent the aging process entirely, our brains are able to adapt and improve at almost any age, as long as we give them the tools and the environment to do so.
But if we’re going to have the lofty yet achievable goal of developing and maintaining a future-proof brain, we need a strategy for how to achieve that. My personal strategy is to think about building what economist Art De Vany calls headroom. Simply defined, headroom is the total amount of function that we have available to us when we really need it. It’s the buffer that we rely on to help us resist the forces of aging over time.
Copyright © 2026 by Dr. Tommy Wood. All rights reserved. No part of this excerpt may be reproduced or reprinted without permission in writing from the publisher.
