A groundbreaking study has revealed the impact LSD (Lysergic acid diethylamide) has on the brain, prompting experts to predict how the drug could be used as part of therapy for those who suffer from depression.
Scans of the brain, under the influence of the drug, showed how the drug enabled networks that normally work separately to form a more "unified brain," similar to the mind of a baby.
Typically the human mind processes visual information using just the visual cortex, a region found in the back of the head.
"However, when the volunteers took LSD, many additional brain areas - not just the visual cortex - contributed to visual processing," the researchers stated.
Lead researcher, Dr Carhart-Harris from the Department of Medicine at Imperial, explained how the brain becomes less compartmentalised under the influence of the drug.
"Our brains become more constrained and compartmentalised as we develop from infancy into adulthood, and we may become more focused and rigid in our thinking as we mature.
"In many ways, the brain in the LSD state resembles the state our brains were in when we were infants: free and unconstrained.
"This also makes sense when we consider the hyper-emotional and imaginative nature of an infant's mind."
It essentially allowed the volunteers to "see with their eyes shut."
The Beckley Foundation partnered with Imperial College on the research.
Its executive director, Amanda Fielding, explained the gravity of the research in a blog for The Huffington Post UK:
"The results of the study are very revealing," she wrote.
"We have shown that psychedelics increase the entropy [chaotic or erratic activity] of the brain to generate a more disordered fluid state of consciousness."
The findings published in Proceedings of the National Academy of Sciences (PNAS) are based on 20 volunteers who were given 75 micrograms of LSD and placebo.
Professor David Nutt, the senior researcher on the study, said the findings could shape the type of therapy patients with depression receive.
"Scientists have waited 50 years for this moment - the revealing of how LSD alters our brain biology.
"For the first time we can really see what's happening in the brain during the psychedelic state, and can better understand why LSD had such a profound impact on self-awareness in users and on music and art.
"This could have great implications for psychiatry, and helping patients overcome conditions such as depression."
Fielding added: "As this state (with LSD) is more flexible and less rigid, it makes people more open to new concepts and ideas.
"This may lead to the breaking of rigid thought patterns such as those found in depression, addiction, and obsessive-compulsive disorder."