Picture your day before you started to read this article. What did you do? In every single moment – getting out of bed, turning on a tap, flicking the kettle switch – your brain was blasted with information. Each second, the eyes will give the brain the equivalent of 10m bits (binary digits) of data. The ears will take in an orchestra of sound waves. Then there’s our thoughts: the average person, researchers estimate, will have more than 6,000 a day. To get anything done, we have to filter out most of this data. We have to focus.

Focusing has felt particularly tough during the pandemic. Books are left half-read; eyes wander away from Zoom calls; conversations stall. My inability to concentrate on anything – work, reading, cleaning, cooking – without being distracted over the past 18 months has felt, at times, farcical.

The good news? We can learn to focus better, but we need to think about attention differently. It is not something we can just choose to do. We have to train the brain like a muscle. Specifically, with short bursts of daily exercises.

Dr Amishi Jha is a professor of cognitive and behavioural neuroscience at the University of Miami and an expert in the science of attention. She has written a book called Peak Mind: Find Your Focus, Own Your Attention, Invest 12 Minutes a Day, a four-week training programme based on her research showing how simple mindfulness exercises carried out by people with high-demand jobs, such as soldiers, elite athletes and emergency medics, improve many aspects of cognitive and emotional health, including strengthening our attention.

When I first opened Peak Mind, I set a timer to see how long it would take me to feel the pull of social media. Three minutes in, I check Twitter. I tell Jha this and she erupts with laughter. “Oh, that’s fantastic,” she says.

I tell her this distractibility has made me anxious. She nods patiently. “There is nothing wrong with your attention, even if you feel more distracted right now. That is a healthy response to your current situation. To think otherwise is just false,” she says. “We’re in a crisis because our attention works so well. It’s doing exactly what it was designed to do: respond powerfully to certain stimuli.”

Stress is one of the biggest obstacles to focusing, says Jha. In a high-alert state, we often start ruminating and catastrophising. We get stuck in “loops of doom” or imagined scenarios. This mode impacts our “working memory”: the amount of information that can be held in our minds and used for a task. For example, choosing the words to put together in an email, or reading a page in a book.

“Working memory is like a mental whiteboard with disappearing ink,” says Jha. When that whiteboard is full of thoughts, feelings and images relating to what’s making us stressed, there is no room for new information. We might start blanking, zoning out or snapping at our partners, then feel guilty, which makes focusing even harder.

Jha began thinking differently about mindfulness when she experienced her own “crisis of attention” (“a blaring, unrelenting onslaught of mental chatter,” she writes) that reduced her ability to feel present with her small children.

So she came up with some simple practices “that exercise the brain in ways that it is prone to being weakened”. These short bursts of mindfulness training each day can help us notice the traffic of our thoughts and urges, and develop what Jha calls the “mental muscle” to observe, rather than act.

I admit that I am sceptical. Even as a trainee psychotherapist (with a vested interest in learning to be present) I find it hard to believe that something so stark, that we can do by ourselves, can help focus a mind that feels scrambled by multiple lockdowns, political divisiveness or economic uncertainty.

I start by setting a timer for three minutes each day, instead of the recommended 12 – a smaller “dose”, encouraged by Jha, to get used to it. The first exercise involves sitting upright, closing your eyes and focusing on where your breathing feels most prominent, usually in the chest or diaphragm. Direct your focus here like a beam and notice when thoughts or sensations pull it away: a memory bubbling up; a reminder that you need to reply to a text; an itch. The point is noticing when the “flashlight” moves, then moving it back. That’s it.

From the beginning, this flashlight image is one of the most useful mindfulness tools I’ve used. After three days, I start to notice when I am being pulled away from trying to focus on something (reading is trickiest for me). I am noticing when my focus is ruptured, which feels new.

The first step to better focus is accepting a key truth, says Jha: you cannot just decide to have unfettered attention. You have to practise. “The notion of an unwavering mind is a fantasy,” she says. The problem is that we now have far more sources of distraction. We are not just recipients of content, but willing participants. Despite how often we are encouraged to “unplug” from our devices, we cannot outwit the algorithms designed by armies of software engineers, statisticians and psychologists.

More unsettling is how we need our phones to rescue us from our phones. The global mindfulness meditation apps market size is expected to reach over $4.2bn by 2027. But in stepping back and learning why our attention can feel so slippery – rather than reaching for another attention-sucking app – perhaps we can assuage some of the difficult emotions associated with being distracted.

In week two, Jha introduces the “body scan”. Using the flashlight to move through the body, from toes to scalp, you are encouraged to notice what physical sensations are there. Whenever the mind wanders, return it to the area of the body where the attention was before the wandering.

Even in three-minute bursts, my mind fizzes with words, people, places and feelings. I tell Jha that I have to move my flashlight back so many times, I wonder if it will ever feel easier. “You’re doing great!” she says. “You have introduced something new and it can take time to get used to it. But know that it will get better.”

After a fortnight of doing the exercises, I notice that being able to carve a little sliver of space between myself and the contents of my mind means I am able to divert my attention back to what I need to do more easily. The body scan exercise has given me a new awareness of how distracted I am by physical sensations (a cramp; a gurgle; an itch). It is hard to explain how significant this layer of awareness is unless you’ve tried it.

I am going to carry on with the exercises, with a view to building up to the 12-minute daily dose, because something is shifting in my relationship with my thoughts. I begin another book after I finish Jha’s and reset my timer. It takes me 23 minutes to open Twitter. That’s progress.

Attention, please: five ways to focus better

1 Pay attention to your breath, and where on your body you feel it most: direct your focus like a beam of light. Do this for three minutes a day, for a week.

2 Integrate this technique into everyday life – for example, brushing your teeth. If you’re thinking about your to-do list as you’re scrubbing, bring the light back. Focus on the sensations.

3 A lot of people report that their mind is “too busy.” Your job is not to stop it – your job is to exist with it, and to place your attention back where you want it.

4 Ignore “mindfulness myths”: you are not “clearing your mind.” This is an active mental workout.

5 There is no “blissed-out” state you are aiming to experience; in fact, the whole point is to be more present to the moment.

• This article was amended on 25 October 2021. The global mindfulness meditation apps market size is expected to reach over $4.2bn by 2027, not $4.2m as stated in an earlier version.

Peak Mind by Amishi Jha (Little, Brown Book Group, £20). To support The Guardian and Observer, order your copy at guardianbookshop.com. Delivery charges may apply.