Researchers Explain How Brain Reacts to a Psychedelic Drug Trip

Psychedelic drugs such as LSD and 'magic mushrooms' are known to alter the way people experience the world. A new study has found that these drugs induce several areas of the brain to become active at the same time, sending users into a dream-like state.

Researchers at the Imperial College London wanted to understand how the brain reacts to these "mind expansion" drugs.

For the study, researchers analyzed brain images of 15 volunteers. The data used in the study was obtained from a study conducted by Dr. Carhart-Harris and Professor David Nutt from the Department of Medicine, Imperial College London.

The participants were given psilocybin intravenously. Psilocybin is a hallucinogenic substance obtained from certain types of mushrooms that grow in tropical forests in parts of South America, U.S. and Mexico.

Brain scans of the participants were taken during the drug trip as well as when they were injected with a placebo.

The team found that the drug led to an increase in activity in the primitive area of the brain. Other areas of the brain such as hippocampus and anterior cingulate cortex also became active. Researchers said that this type of activity is similar to what is seen in a dream-like state.

Volunteers on the drug had more disjointed thinking and uncoordinated activity in brain areas that control self-consciousness.

"What we have done in this research is begin to identify the biological basis of the reported mind expansion associated with psychedelic drugs," said Dr. Robin Carhart-Harris from the Department of Medicine, Imperial College London, according to a news release.

"I was fascinated to see similarities between the pattern of brain activity in a psychedelic state and the pattern of brain activity during dream sleep, especially as both involve the primitive areas of the brain linked to emotions and memory. People often describe taking psilocybin as producing a dreamlike state and our findings have, for the first time, provided a physical representation for the experience in the brain," said Carhart-Harris.

In the new study, researchers also applied a measure called entropy, which was originally developed to quantify lost energy in mechanical systems. Researchers have now found that during a drug trip, entropy increases in primitive part of the brain, meaning that there are more patterns in this region. Researchers believe that the high level of coordination in this region is probably the reason behind the "mind expansion" experience reported by magic mushroom users.

Previous research has shown that the brain always has an optimal level of dynamic networks active. The critical point ensures that there are never too many or too few brain networks active at a given time. The latest study shows that the chemicals in magic mushrooms and LSD can tip this critical balance and create a chaotic state in the brain.

Researchers at Imperial College London are testing the effects of psychedelics on brain to see whether the drug can be used to treat severe depression.

Dr Michael Mosley, medical doctor and TV presenter, took magic mushrooms during a clinical trial in 2010. Read about his experiences, here.

The present study is published in the journal Human Brain Mapping.