LSD brings the brain to the edge of [creative] chaos [without allowing us to topple over it]
“We just solved the same equation, for the harmonic patterns, on the human connectome instead of other geometrical shapes, like metal plates or spheres where it has been applied before,” Atasoy explains. “Then, when we take the fMRI data, instead of looking at where we see higher activity versus lower activity, we can ask the question: How do these harmonic patterns, or connectome harmonics, actually make up the fMRI data.”
By looking at the shape of the brain, Atasoy predicts what wave patterns will emerge on the cortex at many different frequencies. When all the patterns are looked at together, they compose a new language to describe the brain, she says, one that includes both the spatial and temporal elements of neural activity. The patterns tell us which regions should be synchronized with each other at a particular frequency, and then we can describe fMRI data as a combination of these patterns. To wrap my mind around what this means, Atasoy suggests a musical analogy. “It’s as if the brain is playing a musical piece, or it’s like an orchestra,” she says. “The fMRI data gives us the sounds, then what we’re doing is decomposing it into the musical notes; trying to find out which notes are combined in that particular time to create the fMRI sounds that we are ‘hearing.’” This is how they examined the minds of 12 people on LSD, on placebo, and on LSD listening to music, in their new research; not just by seeing how their brain activity changed, but by reading their brain activity through the lens of the brain’s underlying connectome-harmonics. What they found was that under the influence of LSD, more of these harmonics were contributing to brain activity and their strength of activation was also increased. The brain was essentially activating more of its harmonics simultaneously, and in new combinations.Going back to the music analogy, Atasoy says it’s like the difference between someone playing a piece of sheet music and someone improvising. Studies have found that musicians use more notes during improvisation compared to memorized play. The brain, similarly, is expanding its repertoire in a way that wasn’t random; the result is still a coherent piece of “music,” just accessing new notes and scales in combinations that haven’t been heard or played before.