It is known that the use of LSD - psychoactive substances causes rainbow vision and contributes to the loss of the sense of oneself. A team of researchers from Imperial College London is shedding light on what happens in the human brain.
In a series of experiments, scientists at Imperial College London, working with the Beckley Foundation, have gained insight into how psychedelic compounds affect brain activity. Researchers injected LSD (lysergic acid diethylamide) into 20 healthy volunteers at a specialized research center and used a variety of advanced and complementary brain imaging techniques to visualize LSD-induced brain activity.
As a result, LSD was found to induce complex fantasy hallucinations. Under normal conditions, information from our eyes is processed in the visual cortex at the back of the head. However, when the volunteers took LSD, visual processing involved not only the visual zone, but also various additional parts of the brain.
“We noticed that LSD changes the brain. Our volunteers "saw with their eyes closed," explained Dr. Robin Carhart-Harris, study leader. “Although they see things in their imaginations and not in the real world, we saw that many parts of the brain were involved in visual processing - despite the fact that the volunteers' eyes were closed. In addition, the volunteers reported that the greater the magnitude of this effect, the more complex and fantastic the visions were.
Dr. Carhart-Harris explained, “Our brains are usually made up of independent systems that perform specific specialized functions such as vision, movement and hearing, as well as more complex things such as attention. And psychedelic exposure breaks the fragmentation of these systems, and instead we see a more interconnected or unified brain.
“Our results suggest that this effect underlies the profound changes in self-awareness that people often describe while taking LSD. Sometimes people call this state of “dissolution of consciousness”, when the normal sense of self is lost and replaced by a feeling of reunification with oneself, other people and the natural world. This experience is sometimes used in religious or spiritual practices, and may be associated with an improvement in well-being after the drug is stopped."
“As we get older, our brains become more limited and divided, and we become more focused and unyielding in our gaze. In many ways, the brain under the influence of psychedelic drugs resembles that of an infant: free and calm. It may also make sense when examining the hyperemotional and imaginative nature of infant thinking,”added Dr. Carhart-Harris.