Imagine the clouds dripping.Dig a hole in your garden to put them in.

Last week, a pair of new studies revealed some of the first images of neural activity in people who had taken LSD. A far cry from the “This is your brain on drugs” ads of the 1980s, this new research shows that your brain on LSD actually involves a breakdown of the factors that normally keep neural circuits separate. The result? That stereotypical feeling of feeling “at one” with the world and part of something larger than yourself.

“These studies are a real milestone. We’re at the beginning of a new era in psychedelic research. It’s becoming more mainstream,” said Robin Carhart-Wright, a neuroscientist at Imperial College London and co-leader of both of these studies.

...Carhart-Wright and colleagues found that LSD intensified activity in the visual cortex, and that the drug also increased the connections between this region to other parts of the brain. These changes, they believe, are correlated with LSD’s ability to cause visual hallucinations. The researchers observed other changes, too. It simultaneously decreased connections between the parahippocampus and retrosplenial cortex (RSC), brain areas that are involved in memory and navigation. These changes, the scientists believe, are linked to feelings of being part of a larger whole that frequently accompany LSD use.

Our brain normally separates our body from the rest of the world, which is an important step in being able to interact with the environment around us. “LSD breaks down those barriers,” Carhart-Wright said. “It creates stroking and unusual brain changes, creating a more flexible, labile brain,” which is an important factor for people in psychotherapy who are usually trying to enact some form of behavioral change.

In a related study in Current Biology, published two days after the PNAS paper, Carhart-Wright and neuroscientist and physicist Enzo Tagliazucchi, of the University of Kiel in Germany, focused more on this phenomenon, known as ego depletion. Analysis of fMRI images of the brain on LSD reveals that the drug broadly increases the functional connectivity across the entire brain. Increased cross-talk between different brain regions opens the mind to new experiences and seems to integrate the self with the rest of the world.

Other research on psychedelic drugs given to dying cancer patients struggling with anxiety over their impending deaths has shown that this type of experience can be very helpful in relieving the sense of over-arching doom. Building on evidence from more than half a century ago, other studies are showing that these drugs may be helpful in relieving anxiety more broadly. For neuroscientists like Tagliazucchi, however, these drugs provide a novel way to simply understand how the brain goes about its everyday duties.

“We think that what we experience normally is reality, but the truth is our brains are just constructing reality for us,” Tagliazucchi said."