Posts Tagged ‘self’

By Rafi Letzter

Scientists in Switzerland dosed test subjects with LSD to investigate how patients with severe mental disorders lose track of where they end and other people begin.

Both LSD and certain mental disorders, most notably schizophrenia, can make it difficult for people to distinguish between themselves and others. And that can impair everyday mental tasks and social interactions, said Katrin Preller, one of the lead authors of the study and a psychologist at the University Hospital of Psychiatry in Zurich. By studying how LSD breaks down people’s senses of self, the researchers aimed to find targets for future experimental drugs to treat schizophrenia.

“Healthy people take having this coherent ‘self’ experience for granted,” Preller told Live Science, “which makes it difficult to explain why it’s so important.”

Depression, she said, also relates to the sense of self. Whereas people with schizophrenia can lose track of themselves entirely, people with depression tend to “ruminate” on themselves, unable to break obsessive, self-oriented patterns of thought.

But this kind of phenomenon is challenging to study, Preller said.

“If you want to investigate self-experience, you have to manipulate it,” Preller said. “And there are very few substances that can actually manipulate sense of self while patients are lying in our MRI scanner.”

One of the substances that can, however, is LSD. And that’s why this experiment happened in Zurich, Preller said. Switzerland is one of the few countries where it’s possible to use LSD on human beings for scientific research. (Doing so is still quite difficult, though, requiring lots of oversight.)

The experiment itself didn’t sound like the most exciting use of the drug for the test subjects, all of whom were physically healthy and did not have schizophrenia or other illnesses After taking the drug, the subjects lay inside MRI machines with video goggles strapped to their faces, trying to make eye contact with a computer-generated avatar. Once they accomplished this, the subjects then tried to look off at another point in space that the avatar was also looking at. This is the kind of social task, Preller said, that’s very difficult if your sense of self has broken down.

Every study subject tried the task three times: once sober, once on LSD, and once after taking both LSD and a substance called ketanserin. This substance blocks LSD from interacting with a particular serotonin receptor in the brain, which researchers call “5-HT2.”

Previous studies on animals had suggested that 5-HT2 played a key role in LSD’s ability to mess with sense of self. The researchers suspected that blocking the receptor in humans might somewhat reduce the effect of LSD.

But it turned out to more than “somewhat” block the effect: There was no difference between the performance of subjects who took ketanserin and the placebo group.

“This was surprising to us, because LSD interacts with a lot of receptors [in the brain], not just 5-HT2,” Preller said.

But LSD’s most dramatic measurable effects entirely abated when subjects first took ketanserin.

That tentatively indicates that 5-HT2 plays an important role in regulating sense of self in the brain, Preller said. The next step, she added, is to work on drugs that target that receptor and see if they might alleviate some of the symptoms of severe psychiatric illnesses that affect the sense of self.

The paper detailing the study’s results was published today (March 19) at The Journal of Neuroscience.



by Angus Chen

Some users of LSD say one of the most profound parts of the experience is a deep oneness with the universe. The hallucinogenic drug might be causing this by blurring boundaries in the brain, too.

The sensation that the boundaries between yourself and the world around you are erasing correlates to changes in brain connectivity while on LSD, according to a study published Wednesday in Current Biology. Scientists gave 15 volunteers either a drop of acid or a placebo and slid them into an MRI scanner to monitor brain activity.

After about an hour, when the high begins peaking, the brains of people on acid looked markedly different than those on the placebo. For those on LSD, activity in certain areas of their brain, particularly areas rich in neurons associated with serotonin, ramped up.

Their sensory cortices, which process sensations like sight and touch, became far more connected than usual to the frontal parietal network, which is involved with our sense of self. “The stronger that communication, the stronger the experience of the dissolution [of self],” says Enzo Tagliazucchi, the lead author and a researcher at the Netherlands Institute for Neuroscience.

Tagliazucchi speculates that what’s happening is a confusion of information. Your brain on acid, flooded with signals crisscrossing between these regions, begins muddling the things you see, feel, taste or hear around you with you. This can create the perception that you and, say, the pizza you’re eating are no longer separate entities. You are the pizza and the world beyond the windowsill. You are the church and the tree and the hill.

Albert Hofmann, the discoverer of LSD, described this in his book LSD: My Problem Child. “A portion of the self overflows into the outer world, into objects, which begin to live, to have another, a deeper meaning,” he wrote. He felt the world would be a better place if more people understood this. “What is needed today is a fundamental re-experience of the oneness of all living things.”

The sensation is neurologically similar to synesthesia, Tagliazucchi thinks. “In synesthesia, you mix up sensory modalities. You can feel the color of a sound or smell the sound. This happens in LSD, too,” Tagliazucchi says. “And ego dissolution is a form of synesthesia, but it’s a synesthesia of areas of brain with consciousness of self and the external environment. You lose track of which is which.”

Tagliazucchi and other researchers also measured the volunteers’ brain electrical activity with another device. Our brains normally generate a regular rhythm of electrical activity called the alpha rhythm, which links to our brain’s ability to suppress irrelevant activity. But in a different paper published on Monday in the Proceedings of the National Academy of Sciences, he and several co-authors show that LSD weakens the alpha rhythm. He thinks this weakening could make the hallucinations seem more real.

The idea is intriguing if still somewhat speculative, says Dr. Charles Grob, a psychiatrist at the Harbor-UCLA Medical Center who was not involved with the work. “They may genuinely be on to something. This should really further our understanding of the brain and consciousness.” And, he says, the work highlights hallucinogens’ powerful therapeutic potential.

The altered state of reality that comes with psychedelics might enhance psychotherapy, Grob thinks. “Hallucinogens are a catalyst,” he says. “In well-prepared subjects, you might elicit powerful, altered states of consciousness. [That] has been predicative of positive therapeutic outcomes.”

In recent years, psychedelics have been trickling their way back to psychiatric research. LSD was considered a good candidate for psychiatric treatment until 1966, when it was outlawed and became very difficult to obtain for study. Grob has done work testing the treatment potential of psilocybin, the active compound in hallucinogenic mushrooms.

He imagines a future where psychedelics are commonly used to treat a range of conditions. “[There could] be a peaceful room attractively fixed up with nice paintings, objects to look at, fresh flowers, a chair or recliner for the patient and two therapists in the room,” he muses. “A safe container for that individual as they explore deep inner space, inner terrain.”

Grob believes the right candidate would benefit greatly from LSD or other hallucinogen therapy, though he cautions that bad experiences can still happen for some on the drugs. Those who are at risk for schizophrenia may want to avoid psychedelics, Tagliazucchi says. “There has been evidence saying what could happen is LSD could trigger the disease and turn it into full-fledged schizophrenia,” he says. “There is a lot of debate around this. It’s an open topic.”

Tagliazucchi thinks that this particular ability of psychedelics to evoke a sense of dissolution of self and unity with the external environment has already helped some patients. “Psilocybin has been used to treat anxiety with terminal cancer patients,” he says. “One reason why they felt so good after treatment is the ego dissolution is they become part of something larger: the universe. This led them to a new perspective on their death.”