OPEN Foundation

Menu

Author name: OPEN Foundation

Hallucinogens as discriminative stimuli in animals: LSD, phenethylamines, and tryptamines

/ DMT, LSD, Mescaline / Cacti, Mushrooms / Psilocybin, Papers, Publications / /

Abstract

Background: Although man’s first encounters with hallucinogens predate written history, it was not until the rise of the sister disciplines of organic chemistry and pharmacology in the nineteenth century that scientific studies became possible. Mescaline was the first to be isolated and its chemical structure determined. Since then, additional drugs have been recovered from their natural sources and synthetic chemists have contributed many more. Given their profound effects upon human behavior and the need for verbal communication to access many of these effects, some see humans as ideal subjects for study of hallucinogens. However, if we are to determine the mechanisms of action of these agents, establish hypotheses testable in human subjects, and explore the mechanistic links between hallucinogens and such apparently disparate topics as idiopathic psychosis, transcendental states, drug abuse, stress disorders, and cognitive dysfunction, studies in animals are essential. Stimulus control by hallucinogens has provided an intuitively attractive approach to the study of these agents in nonverbal species.

Objective: The intent of this review is to provide a brief account of events from the time of the first demonstration of hallucinogen-induced stimulus control to the present. In general, the review is limited to lysergic acid diethylamide (LSD) and the hallucinogenic derivatives of phenethylamine and tryptamine.

Results: The pharmacological basis for stimulus control by LSD and hallucinogenic phenethylamines and tryptamines is serotonergic in nature. The 5-HT2A receptor appears to be the primary site of action with significant modulation by other serotonergic sites including 5-HT2C and 5-HT1A receptors. Interactions with other neurotransmitters, especially glutamate and dopamine, are under active investigation. Most studies to date have been conducted in the rat but transgenic mice offer interesting possibilities.

Conclusions: Hallucinogen-induced stimulus control provides a unique behavioral tool for the prediction of subjective effects in man and for the elucidation of the pharmacological mechanisms of the action of these agents.

Winter, J. C. (2009). Hallucinogens as discriminative stimuli in animals: LSD, phenethylamines, and tryptamines. Psychopharmacology, 203(2), 251–263. http://dx.doi.org/10.1007/s00213-008-1356-8
Link to full text

Hallucinogens as discriminative stimuli in animals: LSD, phenethylamines, and tryptamines Read More »

The Phenomenology and Potential Religious Import of States of Consciousness Facilitated by Psilocybin

/ Mushrooms / Psilocybin, Neuroscience, Papers, Psychology, Publications / /

Abstract

Accompanying the resumption of human research with the entheogen (psychedelic drug), psilocybin, the range of states of consciousness reported during its action, including both nonmystical and mystical forms of experience, is surveyed and defined. The science and art of facilitating mystical experiences is discussed on the basis of research experience. The potential religious import of these states of consciousness is noted in terms of recognizing the reality of the spiritual, in better understanding the biochemistry of revelation, and in exploring the potentially positive contributions that mystical consciousness may effect in psychological treatment.

Richards, W. A. (2008). The Phenomenology and Potential Religious Import of States of Consciousness Facilitated by Psilocybin. Archive for the Psychology of Religion, 30, 189-199. http://dx.doi.org/10.1163/157361208X317196
Link to full text

The Phenomenology and Potential Religious Import of States of Consciousness Facilitated by Psilocybin Read More »

Ayahuasca and Spiritual Crisis: Liminality as Space for Personal Growth

/ Anthropology & Sociology, Ayahuasca, Papers, Psychology, Psychotic Disorders, Publications / / ,

Abstract

There is an increased controversy surrounding Westerners’ use of ayahuasca. One issue of importance is psychological resiliency of users and lack of screening by ayahuasca tourism groups in the Amazon. Given the powerful effects of ayahuasca coupled with lack of cultural support, Western users are at increased risk for psychological distress. Many Westerners who experience psychological distress following ayahuasca ceremonies report concurrently profound spiritual experiences. Because of this, it may be helpful to consider these episodes “spiritual emergencies,” or crises resulting from intense and transformative spiritual experiences. Although the author warns readers to avoid romantic comparisons of Western ayahuasca users to shamans, ethnographic data on indigenous shamanic initiates along with theory on liminality may be of some use to understand difficult experiences that accompany ayahuasca use. Given that psychotherapy is culturally sanctioned, therapists trained in treating spiritual crises can help Western ayahuasca users make meaning of their distress. Three case studies are offered as examples of individuals working through various sorts of crises following ayahuasca ceremonies.

Lewis, S. E. (2008). Ayahuasca and spiritual crisis: Liminality as Space for Personal Growth. Anthropology of Consciousness, 19(2), 109-133. https://dx.doi.org/10.1111/j.1556-3537.2008.00006.x
Link to full text

Ayahuasca and Spiritual Crisis: Liminality as Space for Personal Growth Read More »

Mystical-type experiences occasioned by psilocybin mediate the attribution of personal meaning and spiritual significance 14 months later

/ Mushrooms / Psilocybin, Papers, Psychology, Publications / / , , , ,

Abstract

Psilocybin has been used for centuries for religious purposes; however, little is known scientifically about its long-term effects. We previously reported the effects of a double-blind study evaluating the psychological effects of a high psilocybin dose. This report presents the 14-month follow-up and examines the relationship of the follow-up results to data obtained at screening and on drug session days. Participants were 36 hallucinogen-naïve adults reporting regular participation in religious/spiritual activities. Oral psilocybin (30 mg/70 kg) was administered on one of two or three sessions, with methylphenidate (40 mg/70 kg) administered on the other session(s). During sessions, volunteers were encouraged to close their eyes and direct their attention inward. At the 14-month follow-up, 58% and 67%, respectively, of volunteers rated the psilocybin-occasioned experience as being among the five most personally meaningful and among the five most spiritually significant experiences of their lives; 64% indicated that the experience increased well-being or life satisfaction; 58% met criteria for having had a ‘complete’ mystical experience. Correlation and regression analyses indicated a central role ofthe mystical experience assessed on the session day in the high ratings of personal meaning and spiritual significance at follow-up. Of the measures of personality, affect, quality of life and spirituality assessed across the study, only a scale measuring mystical experience showed a difference from screening. When administered under supportive conditions, psilocybin occasioned experiences similar to spontaneously occurring mystical experiences that, at 14-month follow-up, were considered by volunteers to be among the most personally meaningful and spiritually significant of their lives.

Griffiths, R. R., Richards, W. A., Johnson, M. W., McCann U. D., & Jesse, R. (2008). Mystical-type experiences occasioned by psilocybin mediate the attribution of personal meaning and spiritual significance 14 months later. Journal of Psychopharmacology, 22(6), 621-632.22: 621-632; http://dx.doi.org/10.1177/0269881108094300
Link to full text

Mystical-type experiences occasioned by psilocybin mediate the attribution of personal meaning and spiritual significance 14 months later Read More »

'Hybrid' benzofuran-benzopyran congeners as rigid analogs of hallucinogenic phenethylamines

/ LSD, Papers, Pharmacology & Chemistry, Publications / / , , , , ,

Abstract

Phenylalkylamines that possess conformationally rigidified furanyl moieties in place of alkoxy arene ring substituents have been shown previously to possess the highest affinities and agonist functional potencies at the serotonin 5-HT2A receptor among this chemical class. Further, affinity declines when both furanyl rings are expanded to the larger dipyranyl ring system. The present paper reports the synthesis and pharmacological evaluation of a series of ‘hybrid’ benzofuranyl–benzopyranyl phenylalkylamines to probe further the sizes of the binding pockets within the serotonin 5-HT2A agonist binding site. Thus, 4(a–b), 5(a–b), and 6 were prepared as homologs of the parent compound, 8-bromo-1-(2,3,6,7-tetrahydrobenzo[fusion_builder_container hundred_percent=”yes” overflow=”visible”][fusion_builder_row][fusion_builder_column type=”1_1″ background_position=”left top” background_color=”” border_size=”” border_color=”” border_style=”solid” spacing=”yes” background_image=”” background_repeat=”no-repeat” padding=”” margin_top=”0px” margin_bottom=”0px” class=”” id=”” animation_type=”” animation_speed=”0.3″ animation_direction=”left” hide_on_mobile=”no” center_content=”no” min_height=”none”][1,2-b:4,5-b0]difuran-4-yl)- 2-aminopropane 2, and their affinity, functional potency, and intrinsic activity were assessed using cells stably expressing the rat 5-HT2A receptor. The behavioral pharmacology of these new analogs was also evaluated in the two-lever drug discrimination paradigm. Although all of the hybrid isomers had similar, nanomolar range receptor affinities, those with the smaller furanyl ring at the arene 2-position (4a–b) displayed a 4- to 15-fold greater functional potency than those with the larger pyranyl ring at that position (5a–b). When the furan ring of the more potent agonist 4b was aromatized to give 6, a receptor affinity similar to the parent difuranyl compound 2 was attained, along with a functional potency equivalent to 2, 4a, and 4b. In drug discrimination experiments using rats trained to discriminate LSD from saline, 4b was more than two times more potent than 5b, with the latter having a potency similar to the classic hallucinogenic amphetamine 1 (DOB).

Schultz, D. M.,  Prescher, J. A., Kidd, S., Marona-Lewicka, D., Nichols, D. E., & Montea, A. (2008). ‘Hybrid’ benzofuran-benzopyran congeners as rigid analogs of hallucinogenic phenethylamines. Bioorganic & Medicinal Chemistry, 16(11), 6242–6251. http://dx.doi.org/10.1016/j.bmc.2008.04.030
Link to full text[/fusion_builder_column][/fusion_builder_row][/fusion_builder_container]

'Hybrid' benzofuran-benzopyran congeners as rigid analogs of hallucinogenic phenethylamines Read More »

[Hallucinogen-induced psychological disorders]

/ LSD, Mushrooms / Psilocybin, Neuroscience, Papers, Psychology, Psychotic Disorders, Publications / / , , ,

Abstract

OBJECTIVE:

The purpose of this article is to provide an overview of the current research on hallucinogen induced psychiatric disorders. In addition to LSD and psilocybin hallucinogens of biologic origin are increasingly used by adolescents and young adults.

METHODS:

Relevant literature and related articles were identified by means of a computerized MEDLINE search including the years 1997 – 2007. As keywords “hallucinogen induced psychosis”, “hallucinogen induced flashback”, “hallucinogen persisting perception disorder (HPPD)” were used. Finally, 64 journal articles and books out of 103 were included in the review.

RESULTS:

Acute psychotic syndromes in adolescents are rarely due to intoxications with hallucinogenic drugs. However, clinical relevance of flashback phenomena as post-hallucinogenic psychiatric disorder has to be disputed. Because of the high popularity of biogenic hallucinogens and LSD knowledge of intoxications and resulting psychiatric disorders as well as medical complications and therapeutical approaches are clinically important. Especially intoxications with drugs of herbal origin like tropanalcaloids play an important role in emergency situations.

Hermle, L., Kovar, K. A., Hewer, W., & Ruchsow, M. (2008). [Hallucinogen-induced psychological disorders]. Fortschritte der Neurologie-Psychiatrie, 76(6), 334-342. http://dx.doi.org/10.1055/s-2008-1038191
Link to full text [Article in German]

[Hallucinogen-induced psychological disorders] Read More »

Identification of N,N-dimethyltryptamine and beta-carbolines in psychotropic ayahuasca beverage

/ Ayahuasca, Biology & Ethnobotany, Papers, Pharmacology & Chemistry, Publications / / , , , ,

Abstract

Recently many people have shown great interest in traditional indigenous practices and popular medicine, involving the ingestion of natural psychotropic drugs. We received a request to analyze and determine the nature of a dark green liquid with a dark brown plant sediment, which the police had seized at an airport and inside the home of a person belonging to the ‘Santo Daime’ religious movement. Gas chromatography/mass spectrometry analysis of the extract identified N,N-dimethyltryptamine, a potent hallucinogen, and the β-carboline alkaloids harmine and harmaline, revealing monoamine oxidase A-inhibiting properties. These substances are typical components of Ayahuasca, a South American psychotropic beverage obtained by boiling the bark of the liana Banisteriopsis caapi together with the leaves of various admixture plants, principally Psychotria viridis.

Gambelunghe, C., Aroni, K., Rossi, R., Moretti, L., & Bacci, M. (2008). Identification of N, N‐dimethyltryptamine and β‐carbolines in psychotropic ayahuasca beverage. Biomedical Chromatography, 22(10), 1056-1059. 10.1002/bmc.1023
Link to full text

Identification of N,N-dimethyltryptamine and beta-carbolines in psychotropic ayahuasca beverage Read More »

Selective 5-HT2A agonist hallucinogens: A review of pharmacological interaction and corollary perceptual effects

/ DMT, LSD, Mushrooms / Psilocybin, Neuroscience, Papers, Psychology, Publications / /

Abstract

The most potent tryptamine hallucinogens – such as DMT, psilocybin, and LSD – are all active at the 5-HT2A receptor subtype and all produce similar visual perceptual results that are immediately recognizable as uniquely psychedelic. Although it is widely accepted that selective serotonin receptor subtype 2A agonism is directly responsible for producing the distinct hallucinations seen on a psychedelic trip, no single theory has yet explained why this is so. Utilizing what we know about psychedelic tryptamine receptor interaction, sensory processing circuits in the neocortex, and EEG scans of psychedelics in action, this review will propose a novel multi-state theory of psychedelic action which invokes a variety of neural processing mechanisms, including phase-coupled neural oscillators; network excitation, disinhibition, and destabilization; recurrent feedback excitation; and neural circuit spike synchrony and brainwave cohesion to close the knowledge gap between the pharmaceutical interactions of selective 5-HT2A hallucinogens, their direct effects on perception and consciousness at varying dose ranges, and their potential long-term adverse effects.

Kent, J. (2008). Selective 5-HT2A agonist hallucinogens: A review of pharmacological interaction and corollary perceptual effects. Beta Review.

Link to full text

Selective 5-HT2A agonist hallucinogens: A review of pharmacological interaction and corollary perceptual effects Read More »

Effects of varied doses of psilocybin on time interval reproduction in human subjects

/ Mushrooms / Psilocybin, Papers, Psychology, Publications / / , , ,

Abstract

Action of a hallucinogenic substance, psilocybin, on internal time representation was investigated in two double-blind, placebo-controlled studies: Experiment 1 with 12 subjects and graded doses, and Experiment 2 with 9 subjects and a very low dose. The task consisted in repeated reproductions of time intervals in the range from 1.5 to 5 s. The effects were assessed by parameter κκ of the ‘dual klepsydra’ model of internal time representation, fitted to individual response data and intra-individually normalized with respect to initial values. The estimates View the MathML sourceκˆ were in the same order of magnitude as in earlier studies. In both experiments, κκ was significantly increased by psilocybin at 90 min from the drug intake, indicating a higher loss rate of the internal duration representation. These findings are tentatively linked to qualitative alterations of subjective time in altered states of consciousness.

Wackermann, J., Wittmann, M., Hasler, F., & Vollenweider, F. X. (2008). Effects of varied doses of psilocybin on time interval reproduction in human subjects. Neuroscience letters, 435(1), 51-55. https://dx.doi.org/10.1016/j.neulet.2008.02.006
Link to full text

Effects of varied doses of psilocybin on time interval reproduction in human subjects Read More »

The correlation between ketamine and posttraumatic stress disorder in burned service members

/ Anxiety Disorders / PTSD, Ketamine, Papers, Psychology, Publications / / , , , ,

Abstract

BACKGROUND:

Predisposing factors for posttraumatic stress disorder (PTSD) include experiencing a traumatic event, threat of injury or death, and untreated pain. Ketamine, an anesthetic, is used at low doses as part of a multimodal anesthetic regimen. However, since ketamine is associated with psychosomatic effects, there is a concern that ketamine may increase the risk of developing PTSD. This study investigated the prevalence of PTSD in Operation Iraqi Freedom/Operation Enduring Freedom (OIF/OEF) service members who were treated for burns in a military treatment center.

METHODS:

The PTSD Checklist-Military (PCL-M) is a 17-question screening tool for PTSD used by the military. A score of 44 or higher is a positive screen for PTSD. The charts of all OIF/OEF soldiers with burns who completed the PCL-M screening tool (2002-2007) were reviewed to determine the number of surgeries received, the anesthetic regime used, including amounts given, the total body surface area burned, and injury severity score. Morphine equivalent units were calculated using standard dosage conversion factors.

RESULTS:

The prevalence of PTSD in patients receiving ketamine during their operation(s) was compared with patients not receiving ketamine. Of the 25,000 soldiers injured in OIF/OEF, United States Army Institute of Surgical Research received 603 burned casualties, of which 241 completed the PCL-M. Of those, 147 soldiers underwent at least one operation. Among 119 patients who received ketamine during surgery and 28 who did not; the prevalence of PTSD was 27% (32 of 119) versus 46% (13 of 28), respectively (p = 0.044).

CONCLUSIONS:

Contrary to expectations, patients receiving perioperative ketamine had a lower prevalence of PTSD than soldiers receiving no ketamine during their surgeries despite having larger burns, higher injury severity score, undergoing more operations, and spending more time in the ICU.

McGhee, L. L., Maani, C. V., Garza, T. H., Gaylord, K. M., & Black, I. H. (2008). The correlation between ketamine and posttraumatic stress disorder in burned service members. Journal of Trauma and Acute Care Surgery, 64(2), S195-S199. https://dx.doi.org/10.1097/TA.0b013e318160ba1d
Link to full text

The correlation between ketamine and posttraumatic stress disorder in burned service members Read More »

Peer Perspectives: Psychedelic Work at the End of Life — The Inner World of the Dying & the Practice of Guiding - Aug 27

REGISTER NOW