Brief history of fantasy, seen through the eyes of science

Creativity and imagination are among the human qualities whose products we most admire. But we could ask ourselves if they are only human characteristics, how they evolved and how old is the history of their evolution. Evolutionary neurobiologists have tried to create a picture that can summarize the current state of knowledge, which is roughly as follows. Let’s start with our ability to remember objects, paths and events: these past memories are encoded by groups of neurons in the neocortex. Remembering a thing or an episode reactivates the same neurons that initially encoded it. Probably all mammals can remember and relive previously encoded objects and events by reactivating the same group of neurons. The memory system based on the neocortex-hippocampus that evolved 200 million years ago then became, according to the most recent theories, the first fundamental step towards the development of the ability to imagine.

The next step in that direction is the ability to build a “memory” that has not really happened, i.e. to codify mental images of objects and events never encountered, so to speak “new” to our experience. The simplest form of constructing new objects and scenes in our minds takes place in the dreams. These vivid and bizarre involuntary fantasies are associated in man with the phase of REM (rapid eye movement) sleep. By homology, the scientists hypothesize that the types of mammals whose rest includes periods of REM sleep experience dreams. Marsupial and placental mammals have REM sleep, but monotremes such as the echidna, an early egg-laying mammal, do not, suggesting that this stage of the sleep cycle evolved after monotremes and the rest of mammals split off. , about 140 million years ago. In fact, the recording of the activity of certain neurons specialized in the brain to encode the memory of places has shown that animals with REM sleep can dream of going to places regardless of the actual perception of reality.

Dream brain activity, i.e. the free reassociation of real or out of thin air memories in our brain during the REM phase of dreaming, has demonstrated different functions of reinforcement and “cleaning” of memory and cognitive processes, but, at the same time, it also represents a form of “uncontrolled” imagination – a way in which, not surprisingly, dreams are often described by poets and artists who sing of nocturnal fantasies. The difference between involuntary imagination, such as dreaming, and voluntary imagination is, according to modern theories, analogous to the difference between voluntary muscle control and muscle spasm. Voluntary muscle control allows people to deliberately combine muscle movements. The spasm occurs spontaneously and cannot be controlled. Likewise, voluntary imagination allows people to deliberately combine their memories – i.e. mental images – and also abstractions derived from the experience of reality. When a subject is asked to mentally superimpose the center of two circles of identical diameter, one immediately imagines that the two circles will correspond perfectly. Similarly, if a subject is asked to imagine composing a bouquet of roses and daisies by collecting 6 flowers of each type, we are able to visualize – ie imagine – the whole process.

This deliberate, reactive and reliable ability to combine and recombine mental objects, derived from memory and from abstractions obtainable by generalization of memorized objects and processes, is called prefrontal synthesis. It relies on the ability of the prefrontal cortex located in the front of the brain to control the rest of the neocortex. When did our species acquire the ability for prefrontal synthesis? As far as we know today, starting with 70,000 years ago this ability was already developed: in fact, there are various archaeological finds that unequivocally indicate its presence, i.e. representations of non-existent creatures (lion-men, for example), bone needles engraved with an eye, bows and arrows, musical instruments, complex burials suggest afterlife beliefs and many other findings. As can be seen, each of the exhibits mentioned implies the synthesis of mental images not found in physical realityand therefore indicate with certainty the existence of the imaginative process due to the prefrontal synthesis.

After 65,000 years ago, artifacts such as those reported appear simultaneously in many geographically distinct locations, roughly coinciding with a major migration of our species out of Africa; if we also look at paleogenetic data and the inferences that can be derived from modern data, it is possible that some individuals have acquired imaginative abilities superior to others, and then spread the trait throughout the human population in a surprisingly rapid way.
The cognitive strategies allowed by the imagination, that is, immediately covered a particularly advantageous adaptive function, quickly making predominant those more imaginative ancestors, who not only imagined and represented their fantasies with a new artistic production, but could use the same brain circuits to plan or mentally explore a still unknown reality, preparing themselves better for it with their imagination . Starting from the very ancient oneiric activity associated with the Rem dream, absent as far as we know today only in the primitive monotremes, we have arrived in hundreds of millions of years to a controlled imagination, capable of giving rise to art, but also to science ; this is, in the light of modern science, the story of our imagination.