More researchers are accepting the power of psychedelics with unprecedented potential to treat disease and psychological trauma, but most of all, to reorganize the brain and shift thought patterns.
Measuring neuron activity has revealed that psychedelic drugs really do alter the state of the brain, creating a different kind of consciousness.
Many researchers have been interested in the idea that psychedelics facilitate communication across the brain and, more specifically, how the default-mode network in the brain, arguably science’s best biological correlate of the self, normally works to constrain this.
“Psychedelics” are substances with the ability to expand human awareness beyond our normal modes of perception. Some may be the most amazing substances known to humanity, so potent that just 1/10,000th of a gram can send one on a journey beyond time and space, beyond life and death.
“We see an increase in the diversity of signals from the brain,” says Anil Seth, at the University of Sussex, UK. “The brain is more complex in its activity.”
In mathematical terms, normal brains have a well-ordered correlation state. There’s not much cross-linking between networks. That changes after the psilocybin dose.
Suddenly the networks are cross-linking like crazy, but not in random ways. New types of order emerge.
“We can speculate on the implications of such an organization,” wrote researchers, who were led by neurobiologist Paul Expert of King’s College London.
“One possible by-product of this greater communication across the whole brain is the phenomenon of synaesthesia” common during psychedelic experiences, of sensory mix-up: tasting colors, feeling sounds, seeing smells, and so on.
While the psychedelic state has been previously compared with dreaming, the opposite effect has been observed in the brain network from which we get our sense of “self” (called the default-mode network or ego-system).
Put simply, while activity became “louder” in the emotion system, it became more disjointed and so “quieter” in the ego system.
The first study, published in Proceedings of the National Academy of Sciences in 2012, revealed decreases in brain activity after injection of psilocybin that were localized to the default-mode network.
Seth and his team discovered this by re-analysing data previously collected by researchers at Imperial College London.
Robin Carhart-Harris and his colleagues had monitored brain activity in 19 volunteers who had taken ketamine, 15 who had had LSD, and 14 who were under the influence of psilocybin, a hallucinogenic compound in magic mushrooms.
Carhart-Harris’s team used sets of sensors attached to the skull to measure the magnetic fields produced by these volunteer’s neurons, and compared these to when each person took a placebo.
“We took the activity data, cleaned it up then chopped it into 2-second chunks,” says Seth, whose team worked with Carhart-Harris on the re-analysis. “For each chunk, we could calculate a measure of diversity.”
Previous work had shown that people in a state of wakefulness have more diverse patterns of brain activity than people who are asleep. Seth’s team has found that people who have taken psychedelic drugs show even more diversity — the highest level ever measured.
These patterns of very high diversity coincided with the volunteers reporting “ego-dissolution” — a feeling that the boundaries between oneself and the world have been blurred. The degree of diversity was also linked to more vivid experiences.
There’s mounting evidence that psychedelic drugs may help people with depression in ways that other treatments can’t.
“I think there’s an awful lot of potential here,” says Seth. “If you suddenly see things in a different way, it could give your outlook a jolt that existing antidepressants can’t because they work on the routine, wakeful state.”