The prediction machine

Lisa Feldman Barrett's book 'Seven and a Half Lessons About the Brain' breaks down some common misconceptions about the brain, including the fallacy of the lizard brain that so much scientific and business literature has been built on. According to Lisa (and science), the brain is essentially a prediction machine in a dark box, using historic data to make predictions and then applying sensory input to confirm them.

Our brains optimize for allostasis and metabolic efficiency, and that's why we act the way we do.

To debunk another common misconception, it's important to understand that our brains don’t react to things in the world. From the moment we are born, we are using past experience to predict what will happen next. We then use sensory data to confirm or correct our prediction. The reason our brains work this way is that they are highly efficient machines. Your brain is in charge of allocating the resources within your body and firing neurons to make changes within a fraction of a second. It's more efficient to predict and correct than to react. Uncertainty is metabolically expensive.

In order to keep you alive, your brain may see rocks on a ledge while you're hiking, knows from experience and learning that rocks can be dangerous, and prepare your body for the possibility of a rock coming loose and whacking you on the head. By preparing metabolically in advance, if your brain does need to fire those neutrons, you save the vital few seconds between life and death.

When our brain makes a prediction based on past experience and gets it wrong, that's called learning. Your brain is constantly aggregating statistical data - the more signals you feed it indicating one thing, the harder it will be to untangle the associated predictions.

Metabolic balances

All this constant processing isn't without cost. Learning new things feels unpleasant because we’re using up glucose and other mental resources that our brain didn't plan ahead and allocate for. The effect is the same whether we're learning a new language, debating with people, or working out. If you replenish what you expend by sleeping, resting, drinking and eating well, you’ll have the energy to learn and continue engaging with new and challenging activities. These remedies are simple but often elusive for many of us amidst the commotion of everyday life.

However, if you’re metabolically encumbered and running a deficit because you’re learning/engaging but not replenishing metabolic expenditure, you won’t have enough energy to devote to learning something new, and so you will automatically look to pare away or deselect any metabolically strenuous activities that make you feel glum. Dealing with other humans adds a layer of unpredictability, and social engagements require us to process a plethora of contextual cues. That’s why it can feel draining. It's also why social media poses such a big problem for so many people. We want to feel connected, but when you're exposed to so many thoughts and opinions and outstanding conversations, you can feel tired and drained before you've even opened your notifications or sent a single reply.

The wormhole in your pocket

There's a lot more we can unpack about the relationship we have with our phones. After owning a phone for as little as a month, between 30 and 90% of people begin to experience something referred to as phantom notification syndrome. Many of us now experience the phenomenon of phantom notifications - your phone might be in your pocket and any slight shift feels like it may have been a vibration. Your phone could be face down on the table and you think you hear something. You could put it away in a bag and still feel the pull of unknown forces.

Through repetition and ritual, you've taught your brain that it gets notifications every few minutes. If you put the phone down you’ll miss a notification. When you get a notification, it’s urgent until proven otherwise. Any moment without our phones is an opportunity for calamity to strike. Before long, your brain is conditioned to react to your phone in the same way it reacted to your ancestors leaving their spear at home before going into the wild. Over time we've trained our brains to believe that being without our phone is dangerous and so, desperately trying to keep us alive, our brains conspire to minimize that risk.

The Impact of Distraction

Our phones have a greater psychological impact on us than we think. Even if you’re not actively using it, studies show that the mere presence of your phone can interfere with your enjoyment of other activities.

Even for the Zen masters who can use their phone while doing another task without adverse impact on the performance of that task, in one study participants with phones had no issue completing set tasks but completely failed to notice a red cross being flashed on their screen.

Another study run over the course of a month featured people dining regularly with family and friends. Interestingly but perhaps predictably, when quizzed about their enjoyment of the dinner overall - both with respect to the food and their dining company, people with their phones out and available rated the experience as less enjoyable versus those who had phones put away.

Going further, in another study participants were asked to put their phone on vibrate and were treated to a massage. During the relaxing spa treatment, they received a call. When asked about the massage later, the subjects that heard their phone vibrate rated their enjoyment far lower than those who didn't.

It turns out that we have very little idea how often our devices can passively steal our attention.

In yet another study, parents were allowed to treat their kids to a trip to the science museum. When objectively rating the experience, the parents who were allowed to use their phones reported less enjoyment and less social connection than those without them.

Before you mistake me for a Luddite, I'll point out that in all these instances there is nothing innate about the phone that obfuscates our enjoyment of everyday life - it’s just the availability of distraction. The use of our phones is bundled with a lot of implicit associations. We turn to them when bored, when lonely, and when seeking to be entertained. We use them to communicate excitement, to calculate, compute and research. Phones are awesome. What's less awesome is the impact of distraction and the fact that we have wormholes of distraction in our pockets that are often the first thing we see in the morning and the last thing we see before bed.

The better we can define the role we want distraction to play in our lives, as well as the associated mental externalities of being constantly connected, the easier it becomes to manage and mitigate its impact.

Come back next week for more on how to master distraction!

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If you have any nuggets to share about the brain and digital connection, I’d love to hear from you! Reply via email, leave a comment or send me a tweet!

Read on for this week’s recommendations >>

A woman walking while using her phone in New York: A photo by David Elikwu
Photo: by David Elikwu, in New York

Reading list

Books I’ve read/seen/will impulsively buy and add to my “to read” shelf on Goodreads. Recommendations from newsletter readers are always welcome:

  1. Seven and a Half Lessons About the Brain by Lisa Feldman Barrett - seen. I’ve recommended Lisa’s books before, but once I heard her doing her book tour across my favourite podcasts, I knew this was a must-buy.
  2. Hooked by Nir Eyal - impulsively bought. A book explaining how companies make products you can’t put down!
  3. Lying by Sam Harris - wishlisted. A recent recommendation that I would have bought instantly if I hadn’t already bought several books that day.

Things I’m loving

Films and shows:

  • Gilmore Girls - This took me an episode or two to get into but it’s growing on me. Thought I’d better watch it and see what the fuss is about before the inevitable reboot. I still keep saying I’ll watch Gossip Girl…
  • The Boys - A dark but fun subversion of the superhero trope. I felt my eyes progressively widening as the season progressed.


  • Audible - I’m sure you’re tired of me going on about Audible but I’ve already crossed the 100-book mark with no signs of slowing down. ALSO, they’re doing a spring sale so you can get 3 months for just 99p. Think of it as three free books of your choice that you can keep forever even if you cancel.

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