Psychedelic drugs: more a case of ‘turn off, tune in, drop out’ Six thousand years ago palaeolithic hunters painted images on the walls of the Selva Pascuala caves in Spain that look remarkably similar to locally abundant Psilocybe hispanica, one of the many “magic mushrooms” that contains the hallucinogen psilocybin. The same or similar mushrooms have been used throughout the ages to induce states of religious ecstasy, spiritual enlightenment, mystical meanderings or simply to have a great time. But how do they work? Timothy Leary, who famously told a generation of Americans to “turn on, tune in, drop out”, claimed these “mind-expanding chemicals … acts as a chemical key – it opens the mind, frees the nervous system of its ordinary patterns and structures”. But a few weeks ago an Imperial College-based research group headed by Professor David Nutt (who was sacked as the government’s chief drug adviser in 2009 after claiming that ecstasy and LSD were less dangerous than alcohol) reported a study that appears to show that, far from expanding the mind, psilocybin shuts it down. The researchers claim that by closing down certain regions of the brain that normally keep our minds on the reality rails, psilocybin may “enable a state of unconstrained cognition”. More “turn off, tune in, drop out”. Professor Nutt suggests that psilocybin may be beneficial in the treatment of psychiatric diseases, such as depression, where the areas affected by the drug are often hyperactive. But perhaps one of the most intriguing aspects of the study is what it tells us about how our brains construct conscious experience. (cont…)

Psychedelic drugs: more a case of ‘turn off, tune in, drop out’

Six thousand years ago palaeolithic hunters painted images on the walls of the Selva Pascuala caves in Spain that look remarkably similar to locally abundant Psilocybe hispanica, one of the many “magic mushrooms” that contains the hallucinogen psilocybin. The same or similar mushrooms have been used throughout the ages to induce states of religious ecstasy, spiritual enlightenment, mystical meanderings or simply to have a great time. But how do they work? Timothy Leary, who famously told a generation of Americans to “turn on, tune in, drop out”, claimed these “mind-expanding chemicals … acts as a chemical key – it opens the mind, frees the nervous system of its ordinary patterns and structures”.

But a few weeks ago an Imperial College-based research group headed by Professor David Nutt (who was sacked as the government’s chief drug adviser in 2009 after claiming that ecstasy and LSD were less dangerous than alcohol) reported a study that appears to show that, far from expanding the mind, psilocybin shuts it down. The researchers claim that by closing down certain regions of the brain that normally keep our minds on the reality rails, psilocybin may “enable a state of unconstrained cognition”. More “turn off, tune in, drop out”.

Professor Nutt suggests that psilocybin may be beneficial in the treatment of psychiatric diseases, such as depression, where the areas affected by the drug are often hyperactive. But perhaps one of the most intriguing aspects of the study is what it tells us about how our brains construct conscious experience.

(cont…)