Unlike more specialised kinds of mental processing, there is no dedicated “imagination cortex” that shows up on brain scans. Instead, imagination is the result of inputs from all corners of the brain and throughout the body.
This article is part of a special series exploring the radical potential of the human imagination. Read more here.
We know that imagination doesn’t come in just one variety (see “The four types of imagination and how they create our worlds”) and isn’t experienced the same by all of us (see “The extremes of imagination reveal how our brains perceive reality”). But in recent years, neuroscientists have begun to get a clearer understanding of how the components of imagination work in the brain.
Advances in scanning the active brain – specifically, functional magnetic resonance imaging (fMRI) – have revealed that it is organised into several key networks. Each shares information within its network while also keeping in touch with others. This allows the brain to switch between different “modes” of thinking by selecting the right network for the job at hand.
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Conjuring creativity
There are three key networks involved in our imaginations. The one most associated with such thought was discovered by accident in the late 1990s, when neuroscientists noticed a distinct pattern of brain activity when research participants were left waiting in fMRI scanners between tasks.
Regions of the brain associated with memory, mood and self-reflection became more active when the participants weren’t occupied by a particular task, signalling an internally focused state of mind. This became known as the default mode network (DMN), and it is in play when we let our minds wander, mull over memories, think about the futureĚýor daydream.
However, the DMN isn’t the only network now known to be involved in what we think of as imagination. If the DMN’s musings are to reach conscious awareness, the brain also needs to loop in the salience network. This connects regions involved in emotion, attention and motivation, acting as a project manager, sifting through external stimuli and internal noise to determine what is significant. In terms of imagination, it is there to flag up ideas and memories that are too important, surprisingĚýor urgent to ignore.
The salience network is also where inputs from the body affect imagination. The network is anchored in the insula, a part of the brain that processes bodily sensations that can be related to emotional states. When these sensations are triggered by our imagination or a memory, for example, the recollection of a frightening experience causing your heart to race, it makes our musings feel more visceral.
Brain imaging studies demonstrate that people who score better on tests of creativity have stronger connections between all three key imagination networks
Though the DMN and salience network can together create an experience of imagination – say, picturing the house you grew up in or the ideal combination of toppings on a pizza – as Evangelia Chrysikou, a creativity researcher at Drexel University in Pennsylvania, says: “Imagination doesn’t equal creativity.” For that, we need another network.
To get creative – in the neuroscientific sense of generating original ideas that serve a purpose in the real world – the brain needs to call on the central executive network.Ěý This links frontal areas to those further back in the parietal cortex, which help direct and sustain our attention so that we can hold a goal in mind while working through possible solutions.
s by Chrysikou and others demonstrate that people who score better on tests of creativity have stronger connections between all three key imagination networks. This might allow them to rapidly switch back and forth between generating, noticing and evaluating ideas.
Improving the imagination
So how can we encourage these systems to work together and improve our imagination? For a start, we can encourage activity in the DMN by taking time to let our mind wander. We can also physically go for a wander: by researchers at Stanford University in California found that a short walk increased creative idea generation by 60 per cent in the moment and for a short time afterwards.
And once you are moving and imagining, try focusing your imagination on something that matters to you. The salience network makes sure that you notice changes related to the excitement of a sudden breakthrough.
This means that the more you care about coming up with a solution, the more likely you are to feel it when inspiration strikes and to find the motivation to act on it.
The evolution of human imagination
The human imagination is a remarkable thing. It has given us the novels of Jane Austen, the songs of R.E.M. – and atom bombs. We can imagine alternative histories in which the second world war didn’t happen, or daydream about a long-lost teenage crush. “All of these things emerge from this human capacity to think beyond the material, or the immediate sensory realm,” says , a biological anthropologist at Princeton University and author of . “Where did this come from? Well, clearly, it evolved.”Ěý
Non-human animals have some degree of imagination. Many can plan ahead: Portia jumping spiders can devise complex attacks on prey, for example. Our imagination is an elaborated version of this.Ěý
We can see the emergence of imagination in the fossil record of our hominin ancestors – especially in the stone tools they made. “To change the shape of a rock into a new form that’s usable requires a kind of imagining that we just don’t see evidence of in other organisms,” says Fuentes.Ěý
The oldest known stone tools are 3.3 million years old, . That’s before our species, or even our genus, Homo, evolved. Clearly, earlier hominins had enough imagination to make and use stone tools. Later, hominins started creating meaning, for instance by painting themselves and cave walls with red ochre, or engraving symbols.
The development of language was a “phase shift” that greatly enabled our imaginations, says Fuentes. “The way in which we have to convey, store and retrieve information opens the door to a lot of other things,” he says. In particular, we can easily convey our ideas to each other – something even our closest relatives, chimpanzees, struggle with.
The importance of language in imagination speaks to a wider point: “Imagining is actually incredibly social,” says Fuentes. “We [often] talk about other people’s imaginations, especially when we talk about artists or geniuses… Our imaginations are not our independent creations, but rather the amalgamations of all of our lived experiences and [the] experiences of so many other people.”
By Michael Marshall
