Article in proceedings of National Academy of Science reveal brain areas activated by psychedelic drug
LSD. Lysergic acid diethylamide. The name of this particular drug conjures up images of the psychedelic 60s and 70s, of hippies, tie-dye and the song “Lucy in the Sky with Diamonds” by the Beatles.
The drug was first synthesized in 1938, although, according to an article by The Guardian, the psychological effects did not become apparent until 1943. From then, the drug became a part of pop culture in the 1950s and 60s. The drug was subsequently made illegal in the 60s, in part due to wide popularity.
The banning of the drug had immediate effects for potential scientific research. Hallucinogens have long been intriguing to scientists particularly because the drugs have a potent effect on a person’s consciousness. Effects of LSD include altered thinking processes, open-eye visuals, synesthesia, spiritual experiences and an altered sense of time. Physiologically, increased heart rate and dilation of pupils often occurs.
A study titled “Neural correlates of the LSD experience revealed by multimodal neuroimaging” carried out by Robin L. Carhart-Harris, Suresh Muthukumaraswamy, Leor Roseman and 23 others was recently published in the Proceedings of the National Academy of Sciences.
Brain scans of 51 individuals under the influence of LSD were compared to individuals under a placebo control condition, and those on the drug showed much more activity throughout the entirety of the brain. When eyes were closed, the LSD participants had significantly more visual experiences than the placebo. 75 micrograms of LSD were delivered intravenously rather than “dropped,” as is the recreational usage of the drug.
The scans of participants’ brains suggested that the there was expanded activity not normally involved with the visual cortex while eyes were closed. This may play a role in the visual hallucinations often reported by users.
The senior researcher of this particular study is David Nutt. He is the former drugs advisor for the United Kingdom, professor of neuropsychopharmacology at Imperial College London and senior researcher on the study.
He said “This is to neuroscience what the Higgs boson was to particle physics. We didn’t know how these profound effects were produced. It was too difficult to do. Scientists were either scared or couldn’t be bothered to overcome the enormous hurdles to get this done.”
The scans performed included arterial spin labelling, resting state MRI and mag ne to ence phalo g raphy. Blood flow, functional connections within and between brain networks and brain waves in the volunteers were all measured.
The scans, according to Nutt’s colleague in the study, Robin Carhart-Harris, said that the participants were “seeing with their eyes shut.” According to Carhart-Harris, despite the eyes being closed, more areas of the brain than “normal” were active and subsequently contributed to the visual processing of LSD.
The study suggested that under the influence of LSD, brain networks dealing with vision, attention, movement and hearing were significantly more interconnected than under the placebo. There was, also, a reduced connection between the parahippocampus and the retrosplenial cortex.
The parahippocampus is thought to be involved in memory encoding and retrieval, and asymmetries may be associated with schizophrenia; the retrosplenial cortex may play roles in episodic memory, navigation, processing future events and may play a role in translating between the the “selfcentered” and “world-centered” spatial information.
It is thought that the neural correlates of LSD’s action may be the primary reason why people experience a state of altered consciousness. Nutt claims that the drug may help in reversing restrictive ways of thinking with potential therapeutic effects on people who experience depression or anxiety.
This study was made possible in large part due to crowdfunding campaigns done by the Beckley Foundation, which focuses on research of psychoactive substances.
Amanda Feilding, the director of the Beckly Foundation, was quoted as saying, “We are finally unveiling the brain mechanisms underlying the potential of LSD, not only to heal, but also to deepen our understanding of consciousness itself.”
All quotes were obtained from The Guardian.