The psychedelic brain state produced by psilocybin was studied using functional magnetic resonance imaging (fMRI) and was found to be similar to the brain state while dreaming. Psilocybin is the substance in “magic mushrooms” that causes psychedelic experiences. The psychedelic state produced by psilocybin was described as unconstrained cognition and profound alterations in the perception of space, time and selfhood by the authors of the fMRI study. Among the general public, the altered state produced by psilocybin is more commonly called “mind expanding” and is thought to produce hallucinations and an altered sense of reality.
The study was published in the journal Human Brain Mapping by researchers in the Department of Medicine at Imperial College London in London. Dr. Robin Carhart-Harris was the lead author of this study that obtained fMRI images from 15 participants after they ingested psilocybin.
Rapid changes in brain dynamics and functional connectivity, meaning activities and connections among neural pathways in the brain, are said to be of increasing interest in the study of brain imaging. Of particular interest is the study of brain states that depart from normal waking consciousness. The rapid changes in brain dynamics and neural pathway activity when under the influence of psilocybin are what the researchers in this study were interested in learning about. They were looking for neural correlates to mind expansion, hallucinations and an altered sense of self. One of the key points of the study is they employed a new methodology to analyze the fMRI results. They used a type of mathematical modeling called Entropy to better analyze the variability in the fMRI images.
The study results showed a wider repertoire of connectivity states after the subjects took psilocybin compared to brain states before they ingested the substance. This means that the pattern of neural activity and connections were expanded in the mind-altered state. The word “unconstrained” would aptly describe this brain state, which rings true to the associated mind-expanded, psychedelic experience.
The results of the study showed that the activity in the brain mostly occurred in areas associated with emotional thinking. An area of the brain called the hippocampus, which has been deemed to be important in memory and emotion, was involved in the dynamic variation, and also the anterior cingulate, which is an area of the brain that has been linked to states of arousal. Since these are two areas of the brain that are known to be active during dreaming, the results of the study suggest that the psychedelic brain state is similar to a dream state. By inference, it suggests that dream experiences that are beyond normal wake-state experiences may be similar to the mind-expanding experiences of hallucinations.
The results also produced an interesting finding in that the brain activity, while under the influence of psilocybin, was unsynchronized and disorganized in areas of the brain thought to be related to self-consciousness. During the days of non-scientific experimentation with psychedelic drugs, primarily in the 1960s, people said they were “changed” and “became a different person” with new self-awareness after taking magic mushrooms or LSD. It seems that modern fMRI studies of the brain showing the psychedelic brain state to be similar to a dream state may be producing the scientific evidence for why those feelings occurred.
By Margaret Lutze