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Life is throwing ever more information our way. But there are simple tricks that can help us cope, says neuroscientist Daniel Levitin

Are we really living in the age of too much information, or do all generations feel like this?
Good question. It seems like human nature to feel as though what鈥檚 happening now is unique. But there has been a measurable shift: in 2011, Americans took in five times as much information every day as they did in 1986. During our leisure time alone, we now process on average 100,000 words each day.

鈥淒uring leisure time alone we now process on average 100,000 words each day鈥�

At some point we are going to exceed our capacity to deal with everything. Maybe we already have. Look at some of the great recent disasters, such as the Exxon Valdez spill. These were caused by people who were overtasked, overworked, sleep deprived and at the limits of their attentional capacity.

Is overload inevitable, then?
Information overload occurs when information comes in faster than we can process it. There isn鈥檛 a threshold 鈥� that鈥檚 the wrong way to look at it. Attention is a limited resource. It鈥檚 the amount of information compared with what we鈥檙e able to deal with at a given time. That changes across lifespan, from person to person, hour to hour. I can deal with more information right now than I can when I am trying to parallel park a car in heavy traffic with two kids in the back.

So the idea of 鈥減aying attention鈥� is apt?
Each time we shift attention, there is a metabolic cost we pay in glucose. We don鈥檛 actually do two, or three or 10 things at once, we just switch from one to another to another. Some brain activities are more expensive than others, and switching attention is among the most expensive. That鈥檚 why air traffic controllers have breaks, when they鈥檙e not allowed to be on call. Their job is like juggling chainsaws. Or people whose job requires updating social media, perhaps a more common example, have to do a lot of attention switching and decision-making 鈥� do I respond to this or let it go? These are the most exhausting things you do.

How can we better use our attention?
One way we cope with information overload is by creating systems to organise information. And some of the best tricks are also the oldest. Written language is remarkable: it lets us offload stuff from our brains and put it out there in the world. It also stops us wasting neural resources by getting stuck in a 鈥渞ehearsal loop鈥�: thinking over and over, 鈥淒on鈥檛 forget to buy milk鈥�. So the biggest way is simply writing things down or putting them in calendars. Then there鈥檚 using the environment 鈥� key hooks for keys or leaving things you want to take with you by the door.

Surely organisational skills have limits? Even the most organised people have junk drawers.
Far from representing a failure, I think junk drawers are a triumph of organisation. Often we鈥檙e busy and have some little thing in our hand and don鈥檛 want to stop and think hard about where to put it, so we make a decision that鈥檚 good enough for now. We reach a point of frustration, all in the space of 5 seconds, and it goes in the junk drawer. That鈥檚 cognitive economy. You鈥檙e not wasting valuable resources on decisions that don鈥檛 matter.

How do we focus on decisions that do matter?
The first thing is to recognise the problem. You have to accept that there are only so many you can make before you become exhausted and unfortunately, trivial decisions don鈥檛 take up fewer neural resources than important ones. Take stock of your life, the decisions you need to make, and then prioritise them.

For the important decisions, figure out if you can make them now or if you need more information. Say we need to decide about putting Aunt Rose in a nursing home. What information do we need? What are the homes like? Does she need a cognitive assessment? Who does that? How do I find them?

Is constant access to information changing how we manage our time?
There is more information now than ever, but we鈥檙e also asked to do more. The expectations of bosses, co-workers, friends and family are greater. And the companies we buy services from are offloading on us. Bagging your own groceries, pumping your gas, making airline reservations, checking yourself in: that鈥檚 shadow work we鈥檙e not getting paid for, nor are we necessarily seeing discounts. These are just the tip of the iceberg in terms of things that we didn鈥檛 have to do before. And again, they use up attentional capacity.

How many things can we pay attention to?
In a famous paper in 1956, psychologist George Miller concluded that you can only pay attention to 鈥�7 卤 2鈥�, so between five and nine items at a time. More recently, Nelson Cowan at the University of Missouri established that it鈥檚 probably only about four. If you walk through your door with the groceries, keys, coat to hang up, the mail in your hand and then the phone rings 鈥� there鈥檚 five right there. You answer the phone and set the keys down absent-mindedly, and because you鈥檙e not focused it never gets encoded in your brain where you put them down or when.

What does the brain do when we pay attention?
There are two networks in the attention system. One is a task positive or central executive network, and it鈥檚 the one that keeps you engaged in a task. The other is a task negative network, or daydreaming mode. It鈥檚 the default state of the brain, when thoughts are loosely connected and you are not controlling what you are paying attention to. When one network is active, the other is not.

How do we switch between modes?
Based on fMRI experiments, my colleague Vinod Menon and I tracked brain activity in situations in which we knew people鈥檚 attention would likely shift between modes. For instance, they listened to music, which has been shown to trigger daydreaming. When there was a dramatic change in the music, we saw heightened activity in a part of the insula known to be the hub of a network dedicated to things we find salient or relevant. This signalled a shift from daydreaming to the central executive mode.

How important is daydreaming?
Daydreaming mode is restorative, and we are often able to form connections between things that weren鈥檛 obvious before. That has been the source of many great insights.

And being organised actually creates the space to daydream?
That鈥檚 a great way to put it. People who get stressed out are the ones who are always in executive mode. The problems you already know how to solve, you can solve with the central executive. The problems you don鈥檛 know how to solve are often solved with daydreaming.

If you can clear your mind by externalising things, making lists or plans to deal with issues that come up, then that reduces the chatter in your head and allows serendipitous connections to fill that space.

Can we make ourselves daydream?
You can induce it 鈥� by listening to music or putting yourself in a relaxing situation. Daniel Kahneman (see 鈥�Understand faulty thinking to tackle climate change鈥�) won a Nobel prize for work in behavioural economics with my former adviser, Amos Tversky. They used to take long walks when they were writing their papers. And we now know that engaging with nature is one thing that can encourage the daydreaming mode.

This article appeared in print under the headline 鈥淚t鈥檚 all too much!鈥�