Infographic: The Brain on Psychedelics

Infographic: The Brain on Psychedelics

Understanding how hallucinogenic drugs affect different neural networks could shed light on their therapeutic potential.

© CATHERINE DELPHIAKey brain areas involved in the effects of psychedelic drugs are located in the default mode network (DMN), which is more active at rest than when attention is focused on the external environment. Neuroscientists first discovered this network while scanning participants’ brains at rest: rather than a decrease in activity across the brain, they found that activity in some regions was actually higher when people were not engaged in a goal-directed task. Over the years, researchers have linked the DMN to a variety of functions, including autobiographical recollection, mind wandering, and processing self-related information.

Source: Infographic: The Brain on Psychedelics

David Nutt – The Psychedelic Crusader

 

David Nutt
The Psychedelic Crusader

In a society where almost all drugs have negative associations, it’s hard to have an open and rational discussion about their potential miraculous effects.

So you used to work as a government adviser. What did that life teach you about how the government approaches drugs, as opposed to what you’re doing now? There must be a huge gap.

Yes, there is an enormous gap. That was the great dissolution and that’s why I got sacked. I spent nine years chairing a committee that did the most systematic analysis of drug harms that has ever been done. It developed new methodologies, published papers, and that was enormously fruitful. I believe that’s what governments should do if they want to make good laws. But it gradually became clear to me during that decade that I was working there that they weren’t interested in the facts. They were very happy with the facts that justified their preconceptions, but the facts that conflicted with their preconceptions they tried to dismiss, or hide, or ignore. In the end it became too oppressive. I suddenly discovered one day, during an interview with one of the BBC home affairs correspondents that I was actually speaking like them. I suddenly thought – who is saying these things? This is not me.  I had to stop the interview and say, no we can’t go on. Then I started telling the truth and within six months I was sacked.

You are very enthusiastic about green-lighting trials in this area and understandably so. We’re talking about people suffering from anxiety and depression. The Default Mode Network is generally overactive in people with those disorders and Psilocybin has been shown to turn off the DMN and allow the brain to behave in ways never seen before. But we still know very little for certain. Isn’t that terrifying?

The point is we don’t know about it because no one has done it before. It’s quite fascinating. Getting some of this stuff published has been quite difficult. A lot of scientists would prefer if this whole thing went away. It raises challenges to philosophies and theories of science. It is like Einstein. We had a nice theory of physics and then suddenly relativity comes along and we have a different theory. Similarly we had a nice theory of consciousness but then our work comes along and says actually there’s another kind of psychedelic consciousness and that’s associated with very different brain activity. All the scientists working in the area of consciousness are saying, “Hey, get out of here. You’re a fucking psychiatrist.” But the truth is we’ve challenged things and shaken things up.

 

“I’m sure that within ten years psilocybin will be an accepted alternative treatment for depression.”

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Source: David Nutt – The Psychedelic Crusader

Functional Connectivity Measures After Psilocybin Inform a Novel Hypothesis of Early Psychosis

Functional Connectivity Measures After Psilocybin Inform a Novel Hypothesis of Early Psychosis

Psilocybin is a classic psychedelic and a candidate drug model of psychosis. This study measured the effects of psilocybin on resting-state network and thalamocortical functional connectivity (FC) using functional magnetic resonance imaging (fMRI). Fifteen healthy volunteers received intravenous infusions of psilocybin and placebo in 2 task-free resting-state scans.

Primary analyses focused on changes in FC between the default-mode- (DMN) and task-positive network (TPN). Spontaneous activity in the DMN is orthogonal to spontaneous activity in the TPN, and it is well known that these networks support very different functions (ie, the DMN supports introspection, whereas the TPN supports externally focused attention). Here, inde- pendent components and seed-based FC analyses revealed increased DMN-TPN FC and so decreased DMN-TPN orthogonality after psilocybin.

Increased DMN-TPN FC has been found in psychosis and meditatory states, which share some phenomenological similarities with the psychedelic state. Increased DMN-TPN FC has also been observed in sedation, as has decreased thalamocortical FC, but here we found preserved thalamocortical FC after psilocybin. Thus, we propose that thalamocortical FC may be related to arousal, whereas DMN-TPN FC is related to the separateness of internally and externally focused states. We suggest that this orthogonality is compromised in early psychosis, explaining similarities between its phenomenology and that of the psychedelic state and supporting the utility of psilocybin as a model of early psychosis.

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LSD enhances suggestibility in healthy volunteers

LSD enhances suggestibility in healthy volunteers

Lysergic acid diethylamide (LSD) has a history of use as a psychotherapeutic aid in the treatment of mood disorders and addiction, and it was also explored as an enhancer of mind control.

Objectives

The present study sought to test the effect of LSD on suggestibility in a modern research study. Methods Ten healthy volunteers were administered with intravenous (i.v.) LSD (40–80 µg) in a within-subject placebo- controlled design. Suggestibility and cued mental imagery were assessed using the Creative Imagination Scale (CIS) and a mental imagery test (MIT). CIS and MIT items were split into two versions (A and B), balanced for ‘efficacy’ (i.e. A˜B) and counterbalanced across conditions (i.e. 50 % completed version ‘A’ under LSD). The MIT and CIS were issued 110 and 140 min, respectively, post-infusion, corresponding with the peak drug effects.

Results

Volunteers gave significantly higher ratings for the CIS (p=0.018), but not the MIT (p=0.11), after LSD than placebo. The magnitude of suggestibility enhancement under LSD was positively correlated with trait conscientiousness measured at baseline (p=0.0005).

Conclusions

These results imply that the influence of suggestion is enhanced by LSD. Enhanced suggestibility under LSD may have implications for its use as an adjunct to psychotherapy, where suggestibility plays a major role. That cued imagery was unaffected by LSD implies that suggestions must be of a sufficient duration and level of detail to be enhanced by the drug. The results also imply that individuals with high trait conscientiousness are especially sensitive to the suggestibility-enhancing effects of LSD.

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User perceptions of the benefits and harms of hallucinogenic drug use

User perceptions of the benefits and harms of hallucinogenic drug use: A web-based questionnaire study

 
This study used a web-based questionnaire to investigate user perceptions of the benefits and harms of hallucinogenic drug use. Over 600 forms were submitted. Users were asked to comment on the acute and prolonged effects of different drugs and to provide more specific information on how particular drugs have harmed and/or helped them.

Subjects reported relatively less harm associated with the classic hallucinogens, LSD and psilocybin, than other drugs specifically focused on in the questionnaire (MDMA, cannabis, ketamine and alcohol). A wide-range of benefits was reported, including: help with mood disorders, addictions and migraine as well as more general long-term improvements in wellbeing. Symptoms of hallucinogen persisting perceptual disorder were reported by a number of subjects and these were most closely associated with use of LSD; however, few users regarded these effects as troubling.

Eighty-one per cent of users reported having had a ‘spiritual experience’ on a hallucinogenic drug and over 90% considered ‘access to the unconscious mind’ to be a specific property of the classic hallucinogens. With caution, these findings support recent calls for a systematic investigation of the therapeutic potential of the classic hallucinogens and highlight the scope for empirical investigations of spiritual and psychodynamic phenomena.

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Finding the Self by Losing the Self

Finding the Self by Losing the Self: Neural Correlates of Ego-Dissolution Under Psilocybin

Alexander_HBM_ego-thumbnailEgo-disturbances have been a topic in schizophrenia research since the earliest clinical descriptions of the disorder.

Manifesting as a feeling that one’s “self,” “ego,” or “I” is disintegrating or that the border between one’s self and the external world is dissolving, “ego-disintegration” or “dissolution” is also an important feature of the psychedelic experience, such as is produced by psilocybin (a compound found in “magic mushrooms”).

Fifteen healthy subjects took part in this placebo- controlled study. Twelve-minute functional MRI scans were acquired on two occasions: subjects received an intravenous infusion of saline on one occasion (placebo) and 2 mg psilocybin on the other.

Twenty-two visual analogue scale ratings were completed soon after scanning and the first principal component of these, dominated by items referring to “ego-dissolution”, was used as a primary measure of interest in subsequent analyses. Employing methods of connectivity analysis and graph theory, an association was found between psilocybin-induced ego-dissolution and decreased functional con- nectivity between the medial temporal lobe and high-level cortical regions. Ego-dissolution was also associated with a “disintegration” of the salience network and reduced inter hemispheric communication.

Addressing baseline brain dynamics as a predictor of drug-response, individuals with lower diversity of executive network nodes were more likely to experience ego-dissolution under psilocybin. These results implicate MTL-cortical decoupling, decreased salience network integrity, and reduced inter-hemispheric communication in psilocybin-induced ego disturbance and suggest that the maintenance of “self”or “ego,” as a perceptual phenomenon, may rest on the normal functioning of these systems.


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