Everyday awareness isn’t optimal. Psychedelics are one way to improve things.

Continuing with my posts about In Search of Now: The Science of the Present Moment by Jo Marchant, my reading of the book brought me to a subject that was dear to my heart back in my college days: how psychedelics like LSD and mescaline can open the mind to an expanded view of reality.

Marchant had been describing how what seems to be the present moment actually is infused by the brain with both our past experiences and predictions of the future. I shared some passages about this in my previous post about In Search of Now.

She then noted how time perception is so critical for our sense of self.

Without the ability to experience the flow of events as continuous, or to predict what’s coming next, we can no longer trust the stability and integrity of things in the world — including our own body and even our own consciousness. Experience becomes fragmented, frozen, and we don’t feel like the same person from one moment to the next.

…When the fundamental structure of time perception begins to break down, so does our awareness, our connection with reality. We are literally held together by a stable, continuous Now. What happens, then, when our sense of time stops completely?

It’s difficult to make this happen on our own, though meditation is a way. But there’s a shortcut: psychedelic drugs.

At the highest drug doses, time can dissolve altogether. And when time goes, it seems, so does people’s sense of self. Even our deepest held distinctiveness melts away, and the feeling of being an individual or ‘I’, separate from the world, disappears. This dissolution can happen gradually, with boundaries blurring and people feeling more connected to their surroundings: to nature or the cosmos.

…But in extreme versions of the experience, all concepts and identities are lost and time simply stops. It’s a phenomenon that has been described as ‘annihilation’ or even ‘ego death’. In this state, there are no seconds, months, or years. No past or future. No questions or answers, memories or desires, departures or destinations.

Just….is. A held note.

…The fact that chemicals can so immediately and dramatically dismantle our perception of time is further evidence that our rich sense of Now, with its interwoven threads and forward flow, isn’t something inevitable, given to us by the universe, but is built from within.

Marchant then discusses how the brain does this, diving into the deep waters of entropy, a measure of disorder. An ordered brain with low entropy is easy to predict, like “soldiers marching in lockstep, all following the same pattern with no freedom to do anything different.” A disordered brain with high entropy is less predictable, “like a group of unsupervised toddlers playing on their own.”

Whereas dancers expressing themselves while also responding to each other would be somewhere in between, she [a neuroscientist] suggests, ‘A very complex order emerges spontaneously.’ There’s growing evidence that the brain does indeed function within this crucial region, poised between order and chaos. Borrowing from work on complex dynamic systems more generally, it’s a state known as ‘criticality’.

I find what Marchant speaks of next to be fascinating. It fits with what I and so many other people are looking for through meditation, psychedelics, and other sorts of experiences that alter the normal functioning of mind/brain. She says that numerous studies have shown that when the entropy, or uncertainty, of key features of the brain drop below normal, so does the level of consciousness.

But what is “normal”?

Until a few years ago, the highest entropy levels that neuroscientists had seen were in brains in the normal, waking state. In all other states — if people were asleep, anesthetized, in a vegetative state — entropy dropped. But in 2017, when Robin Carhart-Harris, a neuroscientist based at Imperial College, London, and his colleagues scanned the brains of volunteers who had taken psychedelic drugs including LSD and psilocybin,  they were surprised to find that during these psychedelic experiences, entropy increased.

In important networks linked to high-level thinking, brain activity became more complex: more random and harder to predict. It was the first time that such an effect had been seen. Carhart-Harris concluded: “Maybe this is a neural signature of the mind opening.’

…Until this point, researchers had assumed that our normal waking awareness represents the brain working right at the peak of its critical zone, where there is maximum complexity and the greatest possible repertoire of conscious states. But studies like this suggest that this isn’t true. In fact, in our everyday lives entropy is suppressed: our brains are operating below maximum criticality.

Although there’s complexity, order still holds sway, reducing the range of possible conscious states. There are limits to where our brains can go, to what we can perceive and think. Our perceptions are constrained by past experience and learned rules. Psychedelics seem to release those limits, tipping the balance of brain activity toward spontaneity and randomness and allowing the brain to nudge closer to that critical peak.

So it can be good to let go of old patterns of thinking and viewing the world, taking a more childlike awe at the magical mystery of the present moment.

Carhart-Harris, along with several other researchers, has framed some of these ideas in terms of predictive coding: the theory that what we perceive isn’t a transparent window onto the world but the brain’s predictions, based on past experience, for the most likely cause of sensory signals we receive. The key concept here is that psychedelics relax the weights, or certainties, of a brain’s predictions. They create a state in which prior assumptions lose their grip on what we perceive right now.

…Over time, our brains become more highly structured: better at predicting both our world and our responses to it. As we find more efficient patterns and associations, though, the flipside is that by definition we become less flexible. Our brains become more constrained. Those prior predictions continually massage and filter incoming sensory data to reduce any mismatch and make them fit what the brain expects.

In other words, everything that we perceive in the present moment is increasingly informed and shaped by what we have perceived in the past. The older we get, the more our perception becomes heavily filtered by a lifetime of experience. Eventually, order trumps spontaneity, and we sink further and further below that critical point as our possibilities shrink. You could see this as the very definition of an ageing brain.

Meditation, Marchant says, can help us let go of past conditioning and experience the present moment in fresh ways. This won’t be as dramatic as taking LSD, but it won’t be as potentially dangerous either.

In fact, the predictive-coding mechanisms described above chime well with the way in which many meditative traditions advocate letting go of the past and future — and therefore the self — by continuously bringing attention back to the present. Buddhists claim, for example, that by becoming less constrained by the past, and more open to Now, we can shed unhelpful baggage that causes suffering and gain a clearer view of reality.