Psychedelics: effects on the human brain and physiology | Simeon Keremedchiev | TEDxVarna

The speaker introduces the topic of psychedelics, emphasizing the importance of understanding the human brain's default mode network and its role in shaping our consciousness and perception. They clarify that the purpose of the talk is not to promote substance use but to stimulate curiosity and challenge the stigma associated with psychedelics. The potential benefits of psychedelics in medicine, research, and personal development are highlighted, along with the need to recognize the brain's automatic functioning and its tendency to operate within set neuronal networks as we age.

This paragraph delves into the definition of psychedelics, derived from ancient Greek meaning 'mind revealing' or 'mind expanding'. It distinguishes psychedelics as a unique category of substances, different from common recreational drugs. The focus shifts to serotonin receptor agonists, specifically psilocybin mushrooms, and their active ingredient, psilocin. The historical and cultural significance of these mushrooms is mentioned, along with their natural occurrence and the profound differences in effects compared to other substances. Research conducted by Professor David Nutt in 2012 and 2014 is introduced, examining the impact of psilocin on the brain's default mode network.

The effects of psilocin on the brain are discussed, highlighting a reduction in blood flow and neuronal activity within the default mode network, leading to a dream-like state. The concept of neuroplasticity is introduced, explaining how the brain creates new connections and pathways for information exchange when the default mode network is less active. The research findings suggest that psilocin enhances overall brain communication, with distant brain areas cooperating and forming new connections, akin to the brain's state during meditation. The visual representation of brain connectivity under placebo and psilocybin is contrasted, emphasizing the natural and unpressured functioning of the brain under the substance's influence.

The paragraph explores the subjective effects of psychedelics, often referred to as 'the trip', which is described as a journey to one's subconscious mind. It discusses the importance of set and setting in shaping the experience and emphasizes the profound emotional and perceptual changes that occur, including heightened color perception, complex visual patterns, and intense memory recall. The experience is said to lead to a loss of self-concept and time perception, eliciting a range of emotions from euphoria to panic. The long-term psychological effects are noted, with reports of increased openness, new perspectives on life, and spiritual understanding persisting months after the experience.

This section contrasts the effects of psychedelics with those of common antidepressants and anxiety relievers, which target the same serotonin receptors but through regulation of re-uptake rather than activation. The speaker criticizes the lack of long-term benefits from a single use of pharmaceuticals and the potential for tissue harm. The absence of addiction potential with psychedelics is highlighted, along with their potential to treat other addictions. A table from the Independent Scientific Committee on Drugs is referenced to illustrate the significantly lower harm profile of LSD and magic mushrooms compared to other substances. The speaker also discusses the potential benefits of psychedelics for patients with autism, ADHD, and OCD, and criticizes the reliance on pharmaceuticals for these conditions.

The final paragraph presents research findings on the long-term significance of psychedelic experiences, particularly for middle-aged adults. It discusses the potential for a 'bad trip' and its value as a learning experience. The research indicates that a significant portion of participants rated their psychedelic experience as one of the most spiritually significant events of their lives, comparable to major life events like the birth of a child or the death of a family member. The speaker concludes by emphasizing the importance of curiosity and exploration in understanding ourselves and the world, and encourages the audience to educate themselves on the current scientific research surrounding psychedelics.