The many states of the brain: What’s going on inside your head and how to optimize it

Do you ever wonder what makes you, well, you: the way you act, the way you feel, the way you process information from the world around you? Some of it is nature (the unique set of genes you inherited), and some of it is nurture (the environment in which you were raised, both within your family and more broadly within a particular culture).

But there are actually so many other, hidden machinations at work, all of which spring from the brain, a part of the body I’ve dedicated my life to understanding. These forces vary from person to person and even change within an individual, depending on time and circumstance. For example, how is it that some of us can exhibit razor-sharp focus while others are distracted by a flash of a big idea or a tiny crumb on the countertop? Or why is it that some of us get a deep thrill being frightened by a scary movie or a creepy book, and what purpose does it really serve?

So, for Season 8 of the “Chasing Life” podcast, I am going back to where all behaviors, moods and impulses start — the brain — to try to unravel the mysteries within. Not only will we peer inside the brain to learn about what is going on, but because our brain is in a constant conversation with our body, we’ll see the impact on our physical selves and how that, in turn, once again affects the brain.

I have been fascinated by the brain since childhood. And throughout my career as a neurosurgeon, I’ve always asked, “How can we build a stronger brain?” How do we keep our brain sharp, more resilient, less likely to develop problems like dementia? Honestly, in the beginning, it was to just try to help my own brain; my grandfather had dementia, and that worried me. But now I want to share what I’ve learned and, frankly, continue to learn with all of you.

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One of the episodes I am most excited about is The Frightened Brain, where I explore why we love a good scare or a good horror movie. You’ll hear a conversation between me and one of my favorite writers of all time, the king (pun very much intended) of horror, Stephen King.

In another episode, The Caffeinated Brain, I talk to writer and fellow journalist Michael Pollan to explore the role of the most widely used psychoactive drug in the world – caffeine: why we like it so much, what happens to our brain when we are on it, and almost as important, what happens when we try to quit.

I’ll also explore what happens to our brain when we express gratitude, swipe on a dating app (over and over again) and eat certain (brain) foods. And I’ll delve into what happens to the brain when the status quo changes, like when women go through menopause, or when a biological process veers off-track, such as when a person develops long Covid, experiences a concussion or battles depression.

At the end of each episode, you’ll get tangible advice from the experts on how to use your brain more effectively, to harness its vast power and make it work more efficiently under different circumstances.

The distracted brain

The first episode of the season, which dropped today, is about the Attentive Brain. It delves into where attention comes from, how it gets hijacked and how to put it back on track.

Gloria Mark, a professor of informatics at the University of California, Irvine, and author of “Attention Span: A Groundbreaking Way to Restore Balance, Happiness and Productivity,” told me how much our attention span had dropped over the course of 20 years: from 2½ minutes in 2003 to 47 seconds today.

Just hearing that left a big impression on me — and I bet it will on you, too. But worse than those alarming numbers are the consequences, both in the real world and to our bodies.

Perhaps nothing exemplifies a short attention span more than the act of multitasking, which many of us wear as a badge of honor, a source of pride — myself included — because we think we are getting more done.

But Mark set me straight. “Humans can’t do two or more things at the same time in parallel. We’re just not built like that. What we’re actually doing is shifting our attention,” she said.

Mark said that kind of constant shifting of attention in our brain is associated with stress, which results in an increase in blood pressure — and that, if it is constant, is not good for our bodies. She said we also make more errors when we multitask, and ironically, it takes us longer to get the task done because there is a mental cost to switching tasks.

“Imagine that you have a whiteboard in your mind, and for every task we do, we have a mental model of what that task is. … And then I suddenly switch, and I do another task: I have to erase that whiteboard and rewrite new information for the new task. And I switch again. I have to erase and rewrite. And just like on a real whiteboard, sometimes you can’t erase it completely,” Mark explained.

So multitasking doesn’t make us happy, faster or more efficient; instead, it makes us stressed and more prone to errors.

Fortunately, Mark gave me some great tips for staying on task.

How do we do better?

TIP #1: Start refreshed

Yes, your mother was right: Getting a good night’s sleep before an important project will help you get and stay focused. Rest helps our executive function skills — the mental processes that enable us to plan, focus and remember — keep sharp.

“When we’re refreshed … we feel energetic. Our executive function can work really well and can help keep us on track. When we’re sleep-deprived or we feel mentally exhausted, executive function doesn’t work so well,” Mark told me. “And in fact, the more exhausted we are, because executive function doesn’t work so well, it makes us more susceptible to being distracted, so we’re more prone to be able to respond to things that are external to our task at hand.”

TIP #2: Design your day according to your natural rhythm

Everybody has times of the day when they are more or less attentive. For example, some people are self-described early birds, others night owls; some people crash after lunch while others get a second wind in the late afternoon. It’s important to listen to your internal rhythm and plan your day accordingly.

“There are peaks and valleys of focus throughout the day, and this corresponds with the ebb and flow of our attentional resources,” Mark explained. “And so to me, it makes the most sense for people to become aware of what your own natural rhythm is, for when you are best able to apply your attentional resources and also when it’s time to pull away to replenish.”

Mark made me figure out my own natural rhythms, and I am going to take full advantage of that knowledge to decide when I reply to email, because my attention is prone to wandering, versus when I knuckle down for a cognitively challenging project, because I am in peak focus.

TIP #3: Don’t let your tank get depleted — stay refreshed

This might seem obvious, but Mark said that our attentional resources are not limitless; like a gas tank, if we use up too much without refilling, we’ll hit Empty.

“So we have a limited tank of attentional resources. And there’s things we do during the day that build up our resources, like taking a break … and there’s things we do that deplete our resources,” Mark said.

Activities that help include taking enough breaks during any project, including going out in nature, to rejuvenate ourselves. Also, she said, “if you have some really important task to do, take a really good break before you begin it. Make sure you’re really, refreshed and ready to do it.”

TIP #4: Tame internal distractions

Phone calls, text notifications, your children interrupting you – those external distractions aren’t the only thing pulling you away from the task at hand.

“[It] turns out that nearly half the time, we are distracted by ourselves. So we have internal interruptions, and it could be an urge, it’s a memory of something that we have to do, it’s this desire to look at social media – so we distract ourselves,” Mark said.

She noted that there’s a lot of things we can do to counteract the internal distractions. “The obvious things: turn off notifications, clear your environment, get things off your desk that can potentially distract you, put your cell phone in a drawer and lock it, make sure the room is quiet. There’s a lot of things people can do to improve their attention,” she said.

Another big source of distractions: unfinished or interrupted tasks. She suggests jotting down to-do list items and random thoughts.

“You keep going over and over in your mind with that [interrupted] task. You don’t want to forget it, right? So … you keep trying to remember it. If something is finished, it’s off your plate. … It’s done. And in fact, there there’s a really nice study that shows that if people want to sleep better, they should write down the interrupted task, because it’s offloading that work of trying to remember the task onto some external memory. The external memory is a piece of paper; you’ve written it down on a piece of paper, so you know you’re not going to forget it. When you wake up in the morning … you’ve got that list of things you still have to do, so you don’t have to rehearse it in your mind,” Mark said.

That made so much sense to me and really explained why I love lists.

TIP #5: Write down your goal, and tape it in front of you

Mark said that because attention is “goal-directed,” it’s really helpful to write two things down when starting a project: what you want to accomplish (a task goal) and how you want to feel (an emotional goal).

“We pay attention to what our goals are. If my goal is that I want to write a paper, that’s what I pay attention to,” she said, adding that it helps if the goals are clear, easily visualized and attainable.

But because goals can easily “slip” if we get distracted, it helps to go through the exercise of asking yourself how you want to feel at the end of the day. For example, I imagine feeling good and enjoying myself after writing that paper.

“Just answering those two questions helped people stay on track,” said Mark.

For more of my conversation with author and professor Gloria Mark, and to learn about the four kinds of attention, click here to listen to the “Chasing Life” podcast. Season 8, on the many states of the brain, starts now!

CNN’s Andrea Kane contributed to this report.