Can integrated information theory explain the psychedelic experience?

In our last blog post “Are we living in a conscious universe?” we looked at a new theory of consciousness called “integrated information theory”. IIT was developed in an attempt to understand the link between the physical world and our experience of consciousness.

In trying to understand what physical systems give rise to our experience of consciousness, IIT makes a basic assumption; that consciousness is part of the basic fabric of the universe. At first this may sound unscientific… but in fact we assume many fundamental laws in science. In physics we assume a fundamental link between matter and gravity without being able to see examine the link directly. James Maxwell had to assume some fundamental electromagnetic laws to develop a theory of electromagnetic fields. And in a similar way, IIT assumes that consciousness arises from physical systems due to some fundamental laws of the universe.

universe

The details of IIT are complex, and involve quite a bit of computational neuroscience. Overall, the basic idea is that any physical system that contains feedback systems has at least some level of consciousness. IIT predicts that our brains, with their highly connected and complex feedback systems, are highly conscious – which we can confirm from our own experience.

So what does IIT predict about the psychedelic state? What changes in the way that information is organised in our brains during the psychedelic experience, and how does that fit in with IIT’s model of consciousness?

Continue reading

Advertisements

Are we living in a conscious universe?

Are you conscious right now?

That’s a pretty easy question to answer. You might say that’s the only thing in life you can ever be totally sure of. You are experiencing existence from moment to moment, and everything else beyond that is… well, just conjecture.

Is a dog conscious? What about a spider? Or a tree? Where do we draw the line of conscious experience, and how can we ever understand something so abstract?

We are always getting closer to understanding how our brains work – and we can link certain physical processes in the brain with behaviours and thoughts – but that still doesn’t answer the hard question: why conscious experience exists. As a philosopher might put it, why is there “something-that-it-is-like-to-be” me? Why does experience seemingly arise from physical systems?

making-up-the-mind

One argument, supported by logical reasoning, is that conscious experience can’t be explained reductively; that is, we can’t explain how I experience colours by reducing the problem down to its most basic parts. Reductive explanation could show me how my brain processes colours, and how it produces all sorts of colour-related behaviours (i.e. stopping at a red light), but it could never explain my own perception of the colour red. Why is my perception of the colour red like this, and not like feeling rain on my skin, or hearing a musical note?

Continue reading

LSD and associative thinking

Earlier this year, researchers at Imperial showed us the first ever detailed images of the brain on LSD. The images showed that LSD massively increased connectivity in the brain, freeing it from its usual boundaries. Now researchers are starting to piece together how LSD breaks down these boundaries of normal consciousness, leading us to an understanding of the workings of the mind.

carhart-harris-2016-mri

MRI scans from Carhart-Harris et al (2016) show how LSD increases brain connectivity

In a recent study from the same UCL group, funded by the psychedelic research charity the Beckley Foundation, researchers looked into how LSD affects our ability to recognise simple objects. The researchers recruited ten participants for their study, almost all of whom were experienced with psychedelic drugs. The subjects attended two experimental sessions: one where they were injected with LSD (40-80μg), and one where they were injected with a placebo. During both placebo and LSD sessions, participants took an object recognition test. They were shown images of simple objects like pieces of clothing or vehicles. As soon as an image appeared, the participants had to name the object as quickly and accurately as they could.

Continue reading