a) Your Brain. b) Your Brain on Shrooms. Any Questions?

This summary graphic from the Royal Society shows the long-range neuronal sprouting that occurs with psilocybin; the untreated brain on the left shows a number of regions with the synaptic connections arranged in a ring of nearest-neighbor connectivity. On the right, you can see the dramatic change, with new spanners across formerly disconnected regions. Instead of a mental model of brain damage, imagine the neuronal sprouting that we associate with fetal development or neural plasticity.

Researchers Robin Carhart-Harris and team also found that that some of these changes in neuronal wiring were permanent.

The effect of this is a more flexible and open mind and visual hallucinations of colored words, numbers or sounds… much like the fascinating condition called synaesthesia.

I first learned of this condition from V.S. Ramachandran, and so I read his book Phantoms in the Brain. Some tidbits from his Bio-X symposium: 1 in 50 people have it. It’s 8x as prevalent among artists, poets, novelists and creative people. Shakespeare was a master: “Juliet is the sun.”

“A word is just a penumbra of associations… a syntactic juggling in the head.”

Often blamed on drugs: “The incidence does go up on LSD, and there are more cases in Berkeley than Stanford.”

Suspected to be a cross wiring in the fusiform gyrus that has a genetic basis given its hereditary pattern in families. The typical synaptic pruning is interrupted by some mutation.

Why doesn’t it disappear from genetic drift? Why would it persist? “They are the outliers in the population. They are more creative. They may be gaining, but evolution moves slowly.” [cue Apple Ad]

At the time, I thought that the mastery of evocative metaphor, in written or visual form, seems like a touch of synaesthesia. Great artists can tap into their internal cross talk, and synaesthesia is the extreme example of what might lie along a spectrum from rationalist to artiste.

It also seems that young children are better at this than the average adult. Given the 10x reduction in synaptic connections at the age of 2 to 3 years, perhaps the benefits of crosstalk are lost in the carvings of maturity.

Here are summary quotes from the new mushroom research:
“The two pictures are simplified cartoons of the placebo (a) and psilocybin (b) scaffolds. The nodes are organized and coloured according to their community membership in the placebo scaffold. This is done in order to highlight the striking difference in connectivity structure in the two cases.

One possible by-product of this greater communication across the whole brain is the phenomenon of synaesthesia, which is often reported in conjunction with the psychedelic state. Synaesthesia is described as an inducer-concurrent pairing, where the inducer could be a grapheme or a visual stimulus that generates a secondary sensory output—like a colour for example. Drug-induced synaesthesia often leads to chain of associations, pointing to dynamic causes rather than fixed structural ones as may be the case for acquired synaesthesia. Broadly consistent with this, it has been reported that subjects under the influence of psilocybin have objectively worse colour perception performance despite subjectively intensified colour experience .

The results show that the homological structure of the brain’s functional patterns undergoes a dramatic change post-psilocybin, characterized by the appearance of many transient structures of low stability and of a small number of persistent ones that are not observed in the case of placebo.

A simple reading of this result would be that the effect of psilocybin is to relax the constraints on brain function, ascribing cognition a more flexible quality, but when looking at the edge level, the picture becomes more complex…these functional connections support cycles that are especially stable and are only present in the psychedelic state. This further implies that the brain does not simply become a random system after psilocybin injection, but instead retains some organizational features, albeit different from the normal state.

To summarize, we presented a new method to analyse fully connected, weighted and signed networks and applied it to a unique fMRI dataset of subjects under the influence of mushrooms. We find that the psychedelic state is associated with a less constrained and more intercommunicative mode of brain function, which is consistent with descriptions of the nature of consciousness in the psychedelic state.”