A Harvard Medical School professor with ADHD shares how he retrained his brain for deep work and reached peak productivity

• Dr. Jeffery Karp grew up with undiagnosed ADHD, struggling to focus and answer questions in class.
• Using two tactics to retrain his brain, Karp gained confidence and pursued a career in academia. 
• The MIT and Harvard professor shares the benefits of working in a flow state in his new book.

As a professor at Harvard Medical School and MIT, I am very lucky; I get to learn from and collaborate with some of the most innovative minds in the world of medicine, science, and technology. But I was not "supposed" to be here. No one would have predicted this for me.

Growing up with undiagnosed ADHD

When I was a kid in elementary school in rural Canada, I had the attention span of a fruit fly, and I struggled to keep up. Reading, writing, classroom discussion, and teachers' instruction — I couldn't make sense of any of it.

It wasn't just that I was distractible and my brain didn't process things in a conventional way; my mind felt completely open to just existing in the world, in a constant mind meld with the universe. It took a ton of effort for me to narrow my focus so stuff could enter, stick, and stay.

And I was an anxious kid. I couldn't relax and just be myself, feel okay as "the quirky kid" because I felt like something worse than that: an alien, a human anomaly. I realized early on that there were many things I was "supposed" to do, but none of them came naturally or seemed logical.

More troubling still was that much of it didn't feel like the right thing to do; it felt actively wrong. When a teacher asked me a question, whether on a test or in class, I typically found the question confusing and often unanswerable. The "right" answer seemed like just one of many possibilities. So, most of my school years were an exercise in trying to figure out, interpret, and fit others' expectations.

I was a puzzle for my teachers, a misfit in the conventional academic sense, and a total outcast socially. Today, with society's much greater understanding of ADHD, part of my eventual diagnosis, there are evidence-based approaches for building self-regulation skills designed for kids (and adults). But at that time and in that place, the only option was to wing it.

Sea slugs were essential in helping me retrain my brain

Over the years, I slowly gained motivation and became more persistent. I didn't know it at the time but my evolution as a learner mirrored the two fundamental concepts of how neurons change and grow — how they learn — that the neuroscientist Eric Kandel would someday identify as the basis that sea slugs and humans have in common for learning and memory: habituation and sensitization in response to repeated exposure to stimuli.

Habituation means that we become less reactive to stimuli, as you might to traffic noise outside your window. Sensitization means that our reaction is stronger, as happens when, for instance, a sound or a smell or even the thought of something becomes a trigger.

Living my own experiment, I learned to make use of both.

I discovered some basic ways to work with my brain to habituate to some stimuli (ordinary things that distracted me) and sensitize (sharpen my attention) to others to be able to reel in my wandering mind and redirect the synaptic messaging with intention. At one point, in the room where I studied there was a pinball machine next to me and a TV behind me. I learned to ignore both and used playing the pinball machine as a reward for finishing my homework.

Over time I became hyperaware of how to intentionally hijack processes in my brain this way to be less reactive or more sharply focused as needed.

The result: I was able to focus on what seemed most purposeful, then follow through and maximize impact as opportunities opened up. I tinkered and fine-tuned until I learned how to use these powerful tools to tap into the heightened state of awareness and deep engagement that I call "lit."

What is 'lit' focus

I call it "lit" for two reasons. First, "lit" aptly describes how the flash of inspiration feels—as if a bright light flipped on in the dark. Or a spark has set your thinking ablaze. When you've had an epiphany, been awestruck, or simply been super excited, you've felt that spark. Second, "lit" is how these moments appear to the scientists who study them. Inside the brain (and in the gut as well), engaged states activate neurons. In the brain, this triggers an increase in cerebral blood flow that neuroscientists can see when they use functional magnetic resonance imaging (fMRI).

On a monitor, this oxygenated blood lights up an otherwise gray image of the brain with yellow-orange hot spots of activity. Emerging science shows that this neural activation is associated not only with particular cognitive activity or emotions such as fear and anger but also with love, awe, happiness, fun, and "peak states," or flow.

In "lit" mode, we engage at the highest level of our abilities. We not only develop the mental muscles to stay focused, but we also build the confidence and the dexterity to riff off of new information on the fly.

We're more likely to use our critical thinking skills, which can keep us from blindly accepting what we're told, or told to believe, especially when our intuition says otherwise. We find it easier to connect with people, are more alive to the possibilities all around us, and are better able to capitalize upon them. In a stream of ever-replenishing energy, we're constantly learning, growing, creating, and iterating. We're building our capacity while doing our best work.

As I honed strategies that enabled me to activate my brain this way at will, I identified a dozen that were simple to use and never failed to open my thinking in just the way that was needed, whatever that was.

Whether it was to direct my attention or disrupt it, sharpen my focus or broaden it, do something stimulating or quiet my mind, these Life Ignition Tools (LIT) worked for me, and then for others as I shared them.

Practicing habits that let me access deep work has been integral to my success

Once I learned how to work with my neuroatypical, voraciously curious, but chaotic brain, I discovered infinite opportunity to question, create, and innovate as a bioengineer and entrepreneur on a global scale and help others do the same. These LIT tools took me from being a confused and frustrated kid, sidelined in a special ed classroom in rural Canada, to becoming a bioengineer and medical innovator elected a fellow of the National Academy of Inventors, the Royal Society of Chemistry, the American Institute for Medical and Biological Engineering's College of Fellows, the Biomedical Engineering Society, and the Canadian Academy of Engineering.

As a professor, I've trained more than 200 people, many of whom are now professors at institutions around the world and innovators in industry; published 130 peer-reviewed papers with more than 30,000 citations; and obtained more than a hundred issued or pending national and international patents. The tools also helped me cofound 12 companies with products on the market or in development.

And finally, they've been instrumental in creating a productive, supportive, and dynamic high-energy environment in my lab, which recently morphed from Karp Lab to the Center for Accelerated Medical Innovation.

Having specific tools helped a struggling kid like me

LIT worked for this kid who appeared to show no promise and the young man who remained frustrated and discouraged for many years. Though I still struggle every day in various ways, I'm grateful to be able to say that these LIT tools enabled me to meet and far exceed those dismal early expectations.

If we want breakthroughs in science and medicine, if we want successful, disruptive innovations on all fronts to support healthier communities, and if we want to cut through the noise and focus on what is most important, we must learn how to use all of the tools in nature's playbook, our evolutionary arsenal. We must shake up our thinking — not just now and then but on a daily basis.

In practice, LIT tools make it possible for us to take anything we're hardwired for — including undesirable or unhelpful behaviors and habits — and with intention, channel the energy in them to create a positive outcome. It's easier than you might think because the more you do it, the greater the rewards, the momentum, and your impact for good.

You're never too old to charge your brain this way, and most definitely no one is ever too young. In fact, LIT tools can be lifesavers for kids, as they were for me.

Adapted from LIT: Use Nature's Playbook to Energize Your Brain, Spark Ideas, and Ignite Action by Jeff Karp, PhD, published by William Morrow. Copyright © 2024 by Jeffrey Michael Karp. Reprinted courtesy of HarperCollinsPublishers.