For the first time ever, researchers have been able to look inside a tripping person's brain.

Breathing neon walls and ego death.

Those are two of the most common side effects of taking acid, but until now, no one's ever been sure why.

Ever since Swiss scientist Albert Hofmann first synthesized LSD in 1938, researchers have been trying to figure out exactly how it effects the brain to produce the characteristic hallucinations and personality dissociation it does. But due to regulatory hurdles and its criminalization as Schedule 1 narcotic, it's been nearly impossible to touch acid, let alone study its inner workings.

However, thanks to the waning taboo around LSD and the exciting potential it has for therapy, a new study published in the Proceedings of the National Academy of Sciences has managed to do the impossible and clear these research hurdles. Now, for the first time ever, researchers have actually been able to peer inside the brains of people tripping balls on acid and see what on earth is happening in there.

The groundbreaking scans reveal the dramatic extent to which the psychedelic drug affects normal brain function, and point towards the use of LSD as a therapy for similar psychological disorders.

Most notably, researchers observed that LSD exacts its mysterious powers by accentuating the power of certain brain regions, while decreasing the function of others. This has lead them to postulate that tripping could unlock childlike-creativity within the brain if they could figure out how to manipulate the areas it stimulates and quiets.

To see this, the researchers used several different imaging techniques, including fMRI and magnetoencephalography (MEG) on a group of 20 volunteers, all of whom had had prior experience with LSD. Half the group was injected with 75 micrograms of LSD (a standard “hit”), while the other half was given a saline solution placebo. 

As the volunteers tripped out in the brain scanners with their eyes closed, the machines recorded the activity of their acid-soaked brains. Afterwards, each volunteer rated and described their visual hallucinations and altered states of consciousness.

Right away, the researchers were taken aback by just how strongly LSD affected the primary visual cortex, the part of the brain that's responsible for processing our environment and helping us perform basic visual tasks like as identifying color, seeing contrasts and lines, and helping with spatial orientation. Usually, when a person is not tripping into another dimension, activity within the visual cortex takes place in a contained, web-shaped network. However, give a person a hit, and that area expands hugely in power and scope, to extent that it's not surprising people describe seeing things such as crawling geometric shapes, radiant colors and inanimate objects that "breathe."

That explains that. But what about the common phenomenon of "ego death" that is so often reported by acid-takers?

Also referred to as "ego dissolution," ego death describes a breakdown of the normal sense of self. 

Most of us sober people take it for granted that we have a constant and immutable sense of self that stays contained within our own bodies and consciousness. This helps us survive, because it provides us with purpose and drive, while allowing us to see ourselves as being distinct from others.

But under the influence of LSD, the sense of self is weakened, and the differences between ourselves and others become less clear. For some people, this translates to mushy feelings of universal connectedness, which is why some users come off acid feeling like they've had transcendent or religious experiences.

“Psychedelics are a stark reminder that the sense of self that we have is kind of precarious,” said lead researcher Robin Carhart-Harris to Gizmodo. “Under LSD, consciousness is still intact—but what’s missing is this sense of self, a sense of having an ego.”

Turns out, there's a distinct physiological reason for this too. It has to do with the parahippocampus and retrosplenial cortex, particular neural networks in the brain that are responsible for self-awareness. When on acid, these areas experience decreased neural connectivity, resulting in a disintegrated sense of self. “The greater this effect, the greater our participants described the experience of ego dissolution,” said Carhart-Harris.

However, once the effects of LSD subside, the sense of self—and normal brain function—is restored.

Apart from solidifying the actual brain activity that's responsible for many of acid's wonderful effects, the research team also discovered just how much LSD trips resemble the brain patterns of certain psychological disorders, particularly early stage psychosis, schizophrenia, and depression. In all these cases, a certain neural inflexibility exists in the brain. However Carhart-Harris thinks that certain drugs, especially psychedelics like acid, could be used to “reboot” the brain as a way to improve its flexibility and plasticity.

These fresh insights are the latest in a growing trend of scientific interest the use of psychedelic drugs for therapy and disease modeling. Hopefully, the results can be used to inspire other researchers to study LSD and its effects on the human brain, because as Carhart-Harris says, "These results really only scratch the surface."