How neuroscience is illuminating the importance of daydreaming

What scientists know as mind-wandering tells us much about what it means to be human. 

NS

Sign Up

Get the New Statesman's Morning Call email.

We all daydream, whether about marrying Rihanna, discovering a sudden ability to sing opera or never having to answer another email again. Yet it is only in the last few decades that the science behind daydreaming, or mind-wandering as it is termed in most academic literature, has transitioned from the realms of pseudoscience to the cutting edge of cognitive neuroscience. 

At its most basic, daydreaming is your mind wandering from the here and now. Traditionally, daydreaming was considered to be a single psychological state of mind. This, however, caused conflict in academic literature, and the resulting confusion is the reason why you might read that daydreaming is linked to happiness in one paper, but to depression in the next. Different types of mind-wandering have been conflated.

Using neuroimaging techniques, a study conducted last year by the University of York found that different types of daydreams – for example, those which are fantastical, autobiographical, future orientated or past oriented – were built up of different neuronal activation patterns, and by virtue could not be considered a single psychological construct. 

Nevertheless, if we consider all these types of mind-wandering together, you would be surprised about how much of our waking time we spend daydreaming. In 2008, Professor Matthew Killingsworth, then at Harvard University, used an app that contacted a large group of people at random points of the day to find out how often they were daydreaming. The app would ask its users what they were doing, and whether they were thinking about something else entirely. They found that 46.9 per cent of the time, the user was mind-wandering.

But how much daydreaming is too much? Maladapative daydreaming is not a clinically recognised condition (as of yet), but many say they suffer from it. Reddit forums have been set up to discuss the so-called mental affliction. Many of these Reddit users say their excessive daydreaming and fantasy life is getting in the way of reality.

Dr Jonathan Smallwood, a researcher at the University of York who specialises in the neuroscience of internal thought, says he believes “daydreaming is an attempt to make sense of life and so it is often increased if lots of change is taking place. Viewed like this, daydreaming is basically not a bad thing but high levels could be an indicator that you are worried about something.

Smallwood also speculates that the fact we daydream so much reflects the evolutionary significance for humans to think creatively.

One network in the brain is particularly heavily implicated in the act of daydreaming. This is called the Default Network Mode, DMN, and consists of, among other parts of the brain, the medial prefrontal cortex and the medial and lateral parietal cortex (all of which are in the top half of the brain). This network is most active when we aren't particularly focused on anything and, intriguingly, also in what is called the theory of mind (when we are thinking about ourselves, or others). 

According to Smallwood, researchers believe daydreams are “generated from representations that are based on information from memory.” A study published last month highlighted how significant memory is to our ability to daydream, and specifically to how we do so, by looking at six patients who had bilateral lesions on their hippocampus – the most important structure in our brains for memory. While the participants were filling in forms, the researcher would ask them “what were you thinking about just before I asked you?” The subject would be encouraged to describe the thought in a sentence or two. The researcher would then note whether the thought had been a visual image or a verbal thought.

The study found that while patients with hippocampal damage could continue to mind-wander and not be present in the moment (at a similar frequency to healthy adults), the nature of their daydreams would take a fascinating turn. These patients would not be able to daydream visually – instead only daydreaming in words. The study was the first of its kind to show a causal relationship between a specific part of the brain and the ability to daydream, and that visual daydreaming is absolutely reliant on our memories. Smallwood suggests this may also be why we daydream less as we get older, but also suggests it could be due to older people having fewer “current concerns” to daydream about. 

Of course, sometimes we purposefully want to not be in the moment, and for that music is a helpful stimulant. An enchanting study published last year tried to uncover how sad and happy music affected our daydreams. The study found that when listening to faster tempo happy music, we focused on the music itself, whereas slower tempo, sad music led to more mentally rich daydreaming. So if you want to avoid distracting daydreaming during a tiresome task that you need to get done as quickly as possible, avoid Radiohead and Lana Del Rey. 

The study also found that while sad music did provoke daydreaming, it did not lead to daydreaming that made you sad. Sad daydreaming is associated with feeling unhappy, and is usually centred on thinking about the past, and how much better you had it back then. Instead, as anyone who has spent a few hours listening to Adele on a cool Sunday morning can attest, it leads to feelings of melancholy, which subjects in the study considered pleasurable. This poses several fascinating questions about the ability of art to evoke emotions that we otherwise would not have access to. 

Ultimately the science of daydreaming, in all its complexities – the amount we do it, what we daydream about and how we can manipulate this behaviour – helps us paint a ever more vivid picture of what means to be human. 

Jason Murugesu is a postgraduate student in science communication at Imperial College London, and a former Wellcome Scholar at the New Statesman.