What is imagination and creativity from a neuroscience perspective?
I will provide an explanation of imagination and creativity that is consistent with current neuroscience knowledge. That does’t mean it is correct or that that a large number of neuroscientists agree with me.
Imagination is rooted in the separation of the hemispheres. The separation is not unique to humans, but only primates seem to have the same separation that I will describe. I suspect aspects of this separation appear in the great apes to a lesser degree, but non-ape primates only show the beginnings of this separation. There is no evidence that non-primate mammals show it, though the jury is still out on birds.
Most animals are firmly connected to the sensations of the real world. Their memories consist of visual, auditory, tactile, and olfactory representations of real events they have experienced. Their “thinking” involves associating current sensations with similar previous sensations and the successful and unsuccessful events that resulted from them. In other words, their mental lives are firmly rooted in sensory reality and the past.
Humans have two ways of thinking that complement each other. This complementarity is what separates us from most other animals. The human right hemisphere works much like that of other animals, though it has additional capabilities that make it more capable than the others, but that’s not today’s subject.
The human left hemisphere is much different that any other animal’s brain. (Except some birds?) It sees the world in a way that no other mammal does, certainly. We see vestiges of the left hemisphere’s way of looking at the world in great apes, but it’s clearly not nearly as developed.
A key recent finding is that the human brain has about twice as many neurons (or more) as any other animal. (Except elephants, but that’s another story.). This means that our brain can be just as smart as any other animal in the original, animal way of thinking, while benefiting from our extra way of thinking.
Before I go further, I want to make clear that this new way of thinking is an amalgam of the skills and viewpoints of the left and right hemispheres. The left hemisphere provides unique skills that make the human way of thinking possible, but neither hemisphere operates independently of the other. Furthermore, everything we do as humans involves the contributions of both hemispheres.
The new skills of the human left hemisphere are what enable imagination and creativity. (I will repeat that imagination and creativity result from the synergy between both hemispheres. Too often these new skills are mistaken for the source of imagination and creativity by themselves.)
The new skills of the left hemisphere involve seeing the world differently than the right hemisphere does and using that different perception to store different kinds of information about the world. While the right side perceives and stores integrated perceptions, primarily images connected to sounds, touch, and olfaction, the left side perceives how the world is constructed and what the pieces look like.
The left hemisphere incessantly deconstructs the world. It uses its direct access to the right side of our high resolution central (foveal) vision to discover all the boundaries in everything we look at. Confident that the right hemisphere sees the whole room, it looks at what is in the room, and once it is confident that it knows what’s in the room, it tries to see what pieces those thing are built from. It sees the chair, among other things, then it sees what the chair is made from (wood?, metal?, cloth?), then it sees how the chair’s legs are constructed and how the upholstery is fitted.
The left hemisphere sees the world as a collection of pieces rather than as a whole. Its memory of the world is essentially a vast collection of pieces and the ways they can be put together. Among the most important pieces in this collection are pieces of sound and the rules for connecting them together to form language. This is why the left hemisphere is the primary source of speech and language in the brain.
This difference between how the left and right sides see the world is most evident in studies of split brain subjects and people with severe strokes, which tend to be limited to one side of the brain or the other. Asking these subjects to draw images of a common object such as a chair shows that the right hemisphere tends to draw some actual chair from memory, while the left hemisphere tends to draw an idealized chair constructed from idealized chair pieces.
While right hemisphere chairs look more comfortable, left hemisphere chairs can be constructed in a myriad of ways, which is the basis for both imagination and creativity. The disadvantage of thinking with pieces is that the pieces are always a bit wrong, but the advantage is that the pieces can be put together in many ways, creating chairs that have never existed before.
Here is where the integration of the left and right hemispheres becomes crucial. While the right hemisphere is largely limited to thinking about chairs that have been seen before, the left hemisphere is handicapped because most of the chairs it imagines are completely useless and unrecognizable as chairs. The process of imagination and creation consists of each hemisphere sharing its workings with the other hemisphere. This isn’t done just once; it is a continual dialog between the hemispheres. Whatever we think about is considered by both hemispheres, continually and usually quickly converging on a unified view of the world.
Iain McGilchrist claims that this process almost always starts with the recognition by the right hemisphere that something about the world doesn’t match our understanding or expectations, leading to an attempt by the left hemisphere to manipulate the pieces of the world to make the understanding right. This leads to the back and forth between the sides to converge on a better understanding of the world.
Imagination and creativity are almost always the result of recognizing that something is wrong or could be better in the world, followed by the hemispheric interplay described above.
