The entropy of consciousness
"Entropy is the normal state of consciousness - a condition that is neither useful nor enjoyable." - (Mihaly Csikszentmihalyi)
How does consciousness emerge from inanimate matter? After all, the atoms that constitute the brain — the birthplace of consciousness — are the same as the atoms that make up the chair you are sitting on. Why are we sentient and self-aware even though a multitude of inanimate objects around us are not? At what point do physical entities — neurons, in this case — give rise to something as abstract as consciousness?
A team of scientists from the University of Toronto and Paris Descartes University has now come up with an intriguing solution to the problem of consciousness. The researchers posit that consciousness is simply a result of the brain trying to maximize its information content. In other words, consciousness emerges because brains — like everything else in the universe — strive to move toward a state of high entropy.
Entropy is basically the term used to describe the progression of a system from order to disorder. The second law of thermodynamics states that entropy in a system always increases, while losing energy at the same time. Thus, a cup can fall and shatter into a hundred pieces — a state of high entropy — but those pieces can never reattach and become an unbroken cup.
This is what many physicists believe is happening to our Universe. After the Big Bang, the Universe has gradually been moving from a state of low entropy to high entropy, and because the second law of thermodynamics states that entropy can only increase in a system, it could explain why the arrow of time only ever moves forwards. The research team decided to apply the same thinking to the connections in our brains, and investigate whether they show any patterns in the way they choose to order themselves while we're conscious.
To figure this out, the researchers used data showing electric- and magnetic-field emissions from the brains of nine people, seven of whom suffered from epilepsy. With emissions recorded at dozens of places across the subjects' scalps, the scientists analysed every possible pairing of these data "channels" to see whether the emissions in each case were in phase with one another. To establish the brain's entropy, they added up the number of synchronized pairs and plugged that figure along with the total number of all possible pairings into a formula called statistical mechanics to work out how many different brain configurations that level of synchronicity yields.
The data were analysed in two parts. In one, they compared the emissions from four of the epileptic patients when undergoing a seizure and when in a normal "alert" state. In the second, they compared emissions from the other five individuals when sleeping and when awake. In both situations, they saw the same trend - the participants' brains displayed higher entropy when in a fully conscious state.
"We sought to identify features of brain organization that are optimal for sensory processing, and that may guide the emergence of cognition and consciousness, by analysing neurophysiological recordings in conscious and unconscious states. We find a surprisingly simple result: normal wakeful states are characterised by the greatest number of possible configurations of interactions between brain networks, representing highest entropy values," the team writes.
Read more: Consciousness as a filter product
This lead the researchers to hint at a possible new hypothesis for why our brains tend to be conscious. They argue that consciousness could simply be an "emergent property" of a system that's trying to maximise information exchange.
To confirm the results, more research will be needed in a larger number of subjects. It's hard to carry out a statistical analysis of the results from only nine people, particularly as everyone's brains responded slightly differently to the various states. Indeed, the complexity of one of the four epileptic patients in the first analysis showed no change between seizure and alert states (although that person did remain conscious during part of the seizure). In another individual, complexity actually increased in the second analysis while that person was asleep. Nevertheless, the results are intriguing, because they were seen in two very different sets of data.
One option to understand if what's happening is really the true definition of entropy, or some other type of organisation, would be to measure the thermodynamic state of different regions. For example, magnetic resonance imaging can be used to measure oxygenation, which is directly related to metabolism and therefore to the generation of heat. The researchers also want to extend their experiments to other brain states - for example, seeing how neural organisation changes when people are concentrating on a task and when they're absent minded or while patients are under anaesthesia.
More information: Let Free Will be
A study on psychedelic drugs, conducted in 2014, found that tripping on magic mushrooms changes the mind by quieting traditional brain activity and jumpstarting new connections between areas of the brain that previously didn't communicate with one another. More recent research showed how people under the influence of LSD appeared to process their visual world in fundamentally different ways, pulling data from multiple parts of their brains. Regions of the brain that normally don't exchange information were connected to another, creating patterns of activity unseen in people who aren't using the drugs.
We're only just beginning to understand how the brain's organisation might affect our consciousness, but it's a pretty fascinating rabbit hole to fall down. And a nice reminder that we're all connected by the laws that govern the Universe.