LSD and the science of losing our sense of self

Taking the psychedelic drug LSD can sometimes give the feeling that the boundaries between you and the rest of the world have disappeared. Images of the brain on LSD now offer an explanation.

Today’s Current Biology study suggests that this phenomenon, known as “ego dissolution”, occurs when regions of the brain that are involved in higher cognition become heavily over-connected. The study also shows that LSD and other psychedelic drugs can offer researchers valuable insights into the brain. We spoke to one of the study’s authors Enzo Tagliazucchi, Royal Netherlands Academy of Arts and Sciences in Amsterdam.

ResearchGate: What is it about LSD and psychedelic drugs that give researchers important insights into the brain?

Enzo Tagliazucchi: First, LSD modifies perception. If we are interested in the neural correlates of vision, for instance, LSD is a powerful tool to induce perceptual changes, even with eyes closed. This can give us insights on how visual percepts are generated by the brain. For instance, the results of a PNAS paper published on Monday show that subjects are perceiving visual imagery with eyes closed ("seeing with eyes shut") and that this visual imagery correlates with markers of enhanced communication and diminished inhibition in the parts of the brain involved in visual perception. This suggests that the brain constantly produces endogenous activity whose perception is actively suppressed, and that loss of this suppression can result in perception.

Second, LSD modifies consciousness. This is what happens during the experience of "ego-dissolution". The brain correlates of self-consciousness are difficult to investigate because an altered sense of the self only appears during certain psychiatric conditions, or can be elicited by electrical stimulation in open-skull brain surgery. LSD can produce such experience safely and in a transient way, and all that it takes is the injection of the drug. This is much easier.

Finally, LSD and certain other psychedelics are selective. They only target certain kinds of receptors in the brain. We can learn about the mechanism of those receptors and how they relate to brain activity in connectivity by using psychedelic drugs.

Enhanced connectivity under LSD vs. placebo. Courtesy of Enzo Tagliazucchi.
Enhanced connectivity under LSD vs. placebo. Courtesy of Enzo Tagliazucchi.

RG: What did your study uncover?

Tagliazucchi: Our study investigated the changes in the brain that are associated with the experience of ego-dissolution. In particular, we measured brain activity with functional magnetic resonance imaging (fMRI). We found that the connectivity of brain networks associated with self-consciousness and introspection was enhanced under LSD. Their connectivity was incremented with parts of the brain in charge of perceiving the external world. And these changes varied in proportion with the intensity of ego-dissolution experienced by the participants.

This suggests that increased cross-talk of these two networks of internal and external consciousness underlies the experience of ego-dissolution and results in a stronger binding of the subject with the external world, at expense of one's identity. Albert Hofmann, discoverer of LSD, explained the loss of ego in these terms: a feeling that one becomes one with the surrounding Universe.

Interestingly, something similar can be seen in certain psychiatric patients who have ego disturbances. The fact that we can transiently induce and study this state with LSD can prove a major breakthrough in the study of these conditions.

Comparing enhanced connectivity under LSD and psilocybin. Courtesy of Enzo Tagliazucchi.
Comparing enhanced connectivity under LSD and psilocybin. Courtesy of Enzo Tagliazucchi.

RG: Can you explain the design of your study?

Tagliazucchi: The study was simple. Subject came to the lab twice, once they received an injection of LSD (75 micrograms) and the other they received a placebo. They didn't know which one they received when. Subjects were scanned with eyes closed using fMRI. Then they were questioned about their experience, including the intensity of experienced ego-dissolution.

RG: For those who haven’t experienced LSD can you try to explain “ego dissolution”?

Tagliazucchi: Ego-dissolution refers to an experience during which the boundaries of the self are expanded or abolished; one is still conscious, but the sense of one's identity is altered and the perception that one is a separated, differentiated individual can be lost. Loss of self-identity can be elicited by psychedelic drugs and also appears in certain psychiatric conditions.

RG: Is it safe? Should it ever be legalized?

Tagliazucchi: LSD is one of the safest drugs known to man. It has very little impact on our body except for modifying consciousness. Fatal doses are not known. It is contraindicated for some psychiatric patients, but could be safely used by most people in a controlled setting. Of course, it might not be a very good idea to drive a car while under the influence of LSD. But the same applies to alcohol. This is why I highlighted words "controlled setting".

The question of legalization is a complex, but the short answer is that LSD is in a category of illegal drugs that is completely dissociated with all known evidence on the harms the drug could cause. In many countries it is in the same category as drugs such as cocaine and heroin. We know that tobacco and alcohol are more dangerous drugs than LSD yet they are legal. I think a change is needed because a drug policy that is not based on evidence is counterproductive on many levels. Very importantly, it undermines the confidence of the people on the authorities in charge of legislating about drugs.

I think drugs such as LSD should be controlled so that harm minimization can be implemented. In the case of LSD this could be, for instance, distributing information about the potential danger of driving a car while under LSD. Currently the government cannot do this because the substance is illegal, so one should not take it, period. I could foresee that injuries related to the use of LSD would drastically diminish if the drug's legal status was changed.

Last but not least, a change in the legal status of the drug could result in easier access to it for scientific experimentation. Currently, research involving LSD is difficult because in many countries this is not only illegal for personal use, but also for scientific and medical research. This is the first thing that should change in my opinion: the acknowledgment that LSD is a useful tool for scientific and medical experimentation.

RG: Do you think LSD has any potential in the treatment of certain conditions?

Tagliazucchi: Yes, psychedelics such as psilocybin have been used in the past for the treatment of anxiety and depression, and there is research under way in Imperial with the purpose of establishing its potential to treat severely depressed patients.

Psilocybin has also been used to alleviate anxiety in terminal cancer patients. Interviews with the patients highlight that the phenomenon of ego-dissolution is at the core of the benefits of taking psychedelics.

LSD elicits similar effects to those of psilocybin so it could also be used for therapeutic purposes. I think the bad reputation of LSD, constructed by the media over decades, has prevented its used and psilocybin has been used instead, but I hope this changes in the future. Our studies could represent a first step towards reverting such bad reputation.

RG: How was this research made possible?

Tagliazucchi: Because of many of the things I mentioned above, research with psychedelics is difficult, also from a financial perspective. This research was possible due to generous funding by the Beckley Foundation and a Walacea crowdfunding campaign, and is part of a wider Beckley-Imperial collaboration directed by Amanda Feilding and David Nutt.

StudyCurrent Biology, Tagliazucchi and Roseman et al.: "Increased Global Functional Connectivity Correlates with LSD-Induced Ego Dissolution" 

Featured image courtesy of serenithyme.