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Psilocybin Biases Facial Recognition, Goal-Directed Behavior, and Mood State Toward Positive Relative to Negative Emotions Through Different Serotonergic Subreceptors

December 19, 2012 / Anxiety Disorders / PTSD, Depressive Disorders, Mushrooms / Psilocybin, Neuroscience, Papers, Psychology, Publications / By / , , , , ,

Abstract

Background
Serotonin (5-HT) 1A and 2A receptors have been associated with dysfunctional emotional processing biases in mood disorders. These receptors further predominantly mediate the subjective and behavioral effects of psilocybin and might be important for its recently suggested antidepressive effects. However, the effect of psilocybin on emotional processing biases and the specific contribution of 5-HT2A receptors across different emotional domains is unknown.

Methods
In a randomized, double-blind study, 17 healthy human subjects received on 4 separate days placebo, psilocybin (215 g/kg), the preferential 5-HT2A antagonist ketanserin (50 mg), or psilocybin plus ketanserin. Mood states were assessed by self-report ratings, and behavioral and event-related potential measurements were used to quantify facial emotional recognition and goal-directed behavior toward emotional cues.

Results
Psilocybin enhanced positive mood and attenuated recognition of negative facial expression. Furthermore, psilocybin increased goal-directed behavior toward positive compared with negative cues, facilitated positive but inhibited negative sequential emotional effects, and valence-dependently attenuated the P300 component. Ketanserin alone had no effects but blocked the psilocybin-induced mood enhancement and decreased recognition of negative facial expression.

Conclusions
This study shows that psilocybin shifts the emotional bias across various psychological domains and that activation of 5-HT2A receptors is central in mood regulation and emotional face recognition in healthy subjects. These findings may not only have implications for the pathophysiology of dysfunctional emotional biases but may also provide a framework to delineate the mechanisms underlying psylocybin’s putative antidepressant effects.

Kometer, M., Schmidt, A., Bachmann, R., Studerus, E., Seifritz, E., & Vollenweider, F. X. (2012). Psilocybin Biases Facial Recognition, Goal-Directed Behavior, and Mood State Toward Positive Relative to Negative Emotions Through Different Serotonergic Subreceptors. Biological Psychiatry, 72(11), 898-906. http://dx.doi.org/10.1016/j.biopsych.2012.04.005
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Durability of improvement in posttraumatic stress disorder symptoms and absence of harmful effects or drug dependency after 3,4-methylenedioxymethamphetamine-assisted psychotherapy: a prospective long-term follow-up study

November 20, 2012 / Anxiety Disorders / PTSD, MDMA, Papers, Psychology, Publications / By / , , , , , ,

Abstract

We report follow-up data evaluating the long-term outcomes for the first completed trial of 3,4-methylenedioxymethamphetamine (MDMA)-assisted psychotherapy for chronic, treatment-resistant post-traumatic stress disorder (PTSD) (Mithoefer et al., 2011). All of the 19 subjects who received MDMA-assisted treatment in the original trial participated in the long-term follow-up (LTFU), with 16 out of 19 completing all of the long-term outcome measures, which were administered from 17 to 74 months after the original study’s final MDMA session (mean = 45.4; SD = 17.3). Our primary outcome measure used was the Clinician-Administered PTSD Scale (CAPS). Secondary outcome measures were the Impact of Events Scale-Revised (IES-R) and the Neuroticism Extroversion Oppenness Personality Inventory-Revised (NEO PI-R) Personality Inventory. We also collected a long-term follow-up questionnaire. Results for the 16 CAPS completers showed there were no statistical differences between mean CAPS score at LTFU (mean = 23.7; SD = 22.8) (t_matched = 0.1; df = 15, p = 0.91) and the mean CAPS score previously obtained at Study Exit (mean = 24.6, SD = 18.6). On average, subjects maintained statistically and clinically-significant gains in symptom relief, although two of these subjects did relapse. It was promising that we found the majority of these subjects with previously severe PTSD who were unresponsive to existing treatments had symptomatic relief provided by MDMA-assisted psychotherapy that persisted over time, with no subjects reporting harm from participation in the study.

Mithoefer, M.C., Wagner, M. T., Mithoefer, A. T., Jerome, L., Martin, S. F., Yazar-Klosinski, B., … Doblin, R. (2012). Durability of improvement in posttraumatic stress disorder symptoms and absence of harmful effects or drug dependency after 3,4-methylenedioxymethamphetamine-assisted psychotherapy: a prospective long-term follow-up study. Journal of Psychopharmacology, 27(1), 1-12. http://dx.doi.org/10.1177/0269881112456611
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A randomized, controlled pilot study of MDMA (± 3,4-Methylenedioxymethamphetamine)-assisted psychotherapy for treatment of resistant, chronic Post-Traumatic Stress Disorder (PTSD)

October 31, 2012 / Anxiety Disorders / PTSD, MDMA, Papers, Psychology, Publications / By / , , ,

Abstract

Psychiatrists and psychotherapists in the US (1970s to 1985) and Switzerland (1988-1993) used MDMA legally as a prescription drug, to enhance the effectiveness of psychotherapy. Early reports suggest that it is useful in treating trauma-related disorders. Recently, the first completed pilot study of MDMA-assisted psychotherapy for PTSD yielded encouraging results. Designed to test the safety and efficacy of MDMA-assisted psychotherapy in patients with treatment-resistant PTSD; our randomized, double-blind, active-placebo controlled trial enrolled 12 patients for treatment with either low-dose (25 mg, plus 12.5 mg supplemental dose) or full-dose MDMA (125 mg, plus 62.5 mg supplemental dose). MDMA was administered during three experimental sessions, interspersed with weekly non-drug-based psychotherapy sessions. Outcome measures used were the Clinician-Administered PTSD Scale (CAPS) and the Posttraumatic Diagnostic Scale (PDS). Patients were assessed at baseline, three weeks after the second and third MDMA session (end of treatment), and at the 2-month and 1-year follow-ups. We found that MDMA-assisted psychotherapy can be safely administered in a clinical setting. No drug-related serious adverse events occurred. We did not see statistically significant reductions in CAPS scores (p = 0.066), although there was clinically and statistically significant self-reported (PDS) improvement (p = 0.014). CAPS scores improved further at the 1-year follow-up. In addition, three MDMA sessions were more effective than two (p = 0.016).

Oehen, P., Traber, R., Widmer, V., & Schnyder, U. (2012) A randomized, controlled pilot study of MDMA (± 3,4-Methylenedioxymethamphetamine)-assisted psychotherapy for treatment of resistant, chronic Post-Traumatic Stress Disorder (PTSD). Journal of Psychopharmacology, 27(1), 40-52. http://dx.doi.org/10.1177/0269881112464827
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Functional Connectivity Measures After Psilocybin Inform a Novel Hypothesis of Early Psychosis

October 8, 2012 / Mushrooms / Psilocybin, Neuroscience, Papers, Psychology, Psychotic Disorders, Publications / By / , , , , , ,

Abstract

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 differ -ent 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 psy -chedelic state. Increased DMN-TPN FC has also been observed in sedation, as has decreased thalamocortical FC, but here we found preserved thalamocortical FC after psi -locybin. 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 phenomenol -ogy and that of the psychedelic state and supporting the utility of psilocybin as a model of early psychosis.

Carhart-Harris, R. L., Leech, R., Erritzoe, D., Williams, T. M.,  Stone, J. M.,  Evans, J., …. Nutt, D. J. (2012). Functional Connectivity Measures After Psilocybin Inform a Novel Hypothesis of Early Psychosis. Schizophrenia Bulletin, 39(6), 1343-1351. http://dx.doi.org/10.1093/schbul/sbs117
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Personality, Psychopathology, Life Attitudes and Neuropsychological Performance among Ritual Users of Ayahuasca: A Longitudinal Study

August 8, 2012 / Ayahuasca, Neuroscience, Papers, Psychology, Publications / By / , , , , , ,

Abstract

Ayahuasca is an Amazonian psychoactive plant beverage containing the serotonergic 5-HT2A agonist N,N-dimethyltryptamine (DMT) and monoamine oxidase-inhibiting alkaloids (harmine, harmaline and tetrahydroharmine) that render it orally active. Ayahuasca ingestion is a central feature in several Brazilian syncretic churches that have expanded their activities to urban Brazil, Europe and North America. Members of these groups typically ingest ayahuasca at least twice per month. Prior research has shown that acute ayahuasca increases blood flow in prefrontal and temporal brain regions and that it elicits intense modifications in thought processes, perception and emotion. However, regular ayahuasca use does not seem to induce the pattern of addiction-related problems that characterize drugs of abuse. To study the impact of repeated ayahuasca use on general psychological well-being, mental health and cognition, here we assessed personality, psychopathology, life attitudes and neuropsychological performance in regular ayahuasca users (n = 127) and controls (n = 115) at baseline and 1 year later. Controls were actively participating in non-ayahuasca religions. Users showed higher Reward Dependence and Self-Transcendence and lower Harm Avoidance and Self-Directedness. They scored significantly lower on all psychopathology measures, showed better performance on the Stroop test, the Wisconsin Card Sorting Test and the Letter-Number Sequencing task from the WAIS-III, and better scores on the Frontal Systems Behavior Scale. Analysis of life attitudes showed higher scores on the Spiritual Orientation Inventory, the Purpose in Life Test and the Psychosocial Well-Being test. Despite the lower number of participants available at follow-up, overall differences with controls were maintained one year later. In conclusion, we found no evidence of psychological maladjustment, mental health deterioration or cognitive impairment in the ayahuasca-using group.

Bouso, J. C, González, D., Fondevila, S., Cutchet, M., Fernández, X., Barbosa, P. C. R., … Riba, J. (2012). Personality, Psychopathology, Life Attitudes and Neuropsychological Performance among Ritual Users of Ayahuasca: A Longitudinal Study. PLoS ONE 7(8), 1-13.  http://dx.doi.org/10.1371/journal.pone.0042421
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Hypotheses regarding the mechanisms of ayahuasca in the treatment of addictions

August 2, 2012 / Ayahuasca, Papers, Psychology, Publications, Substance Use Disorder / By / ,

Abstract

Ayahuasca is a medicinal plant mixture utilized by indigenous peoples throughout the Amazon River basin for healing purposes. The “vine of the soul” or “vine of death,” as it is known in South America, contains a combination of monoamine oxidase inhibitors and N,N-dimethyltryptamine (DMT). When ingested together, these medicines produce profound alterations in consciousness. Increasingly, ayahuasca is being utilized to treat addictions. However, the mechanism of action by which ayahuasca treats addictions remains unclear. We offer four hypotheses to explain possible biochemical, physiological, psychological, and transcendent mechanisms by which ayahuasca may exert its anti-addiction effects.

Liester, M. B., & Prickett, J. I. (2012). Hypotheses regarding the mechanisms of ayahuasca in the treatment of addictions. Journal of psychoactive drugs, 44(3), 200-208. 10.1080/02791072.2012.704590
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The NMDA antagonist ketamine and the 5-HT agonist psilocybin produce dissociable effects on structural encoding of emotional face expressions

July 27, 2012 / Anxiety Disorders / PTSD, Depressive Disorders, Ketamine, Mushrooms / Psilocybin, Neuroscience, Papers, Psychology, Publications / By / , , , ,

Abstract

Rationale
Both glutamate and serotonin (5-HT) play a key role in the pathophysiology of emotional biases. Recent studies indicate that the glutamate N-methyl-D-aspartate (NMDA) receptor antagonist ketamine and the 5-HT receptor agonist psilocybin are implicated in emotion processing. However, as yet, no study has systematically compared their contribution to emotional biases.

Objectives
This study used event-related potentials (ERPs) and signal detection theory to compare the effects of the NMDA (via S-ketamine) and 5-HT (via psilocybin) receptor system on non-conscious or conscious emotional face processing biases.

Methods
S-ketamine or psilocybin was administrated to two groups of healthy subjects in a double-blind within-subject placebo-controlled design. We behaviorally assessed objective thresholds for non-conscious discrimination in all drug conditions. Electrophysiological responses to fearful, happy, and neutral faces were subsequently recorded with the face-specific P100 and N170 ERP.

Results
Both S-ketamine and psilocybin impaired the encoding of fearful faces as expressed by a reduced N170 over parieto-occipital brain regions. In contrast, while S-ketamine also impaired the encoding of happy facial expressions, psilocybin had no effect on the N170 in response to happy faces.

Conclusion
This study demonstrates that the NMDA and 5-HT receptor systems differentially contribute to the structural encoding of emotional face expressions as expressed by the N170. These findings suggest that the assessment of early visual evoked responses might allow detecting pharmacologically induced changes in emotional processing biases and thus provides a framework to study the pathophysiology of dysfunctional emotional biases.

Schmidt, A., Kometer, M., Bachmann, R., Seifritz, E., & Vollenweider, F.X. (2012). The NMDA antagonist ketamine and the 5-HT agonist psilocybin produce dissociable effects on structural encoding of emotional face expressions. Psychopharmacology, 225(1), 227-239. http://dx.doi.org/doi:10.1007/s00213-012-2811-0
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Research on psychedelic substances

July 6, 2012 / Humanities & Art, LSD, Papers, Psychology, Publications / By / ,

Introduction

The term ‘psychedelic ’ (i.e. mind-manifesting) was coined by Humphrey Osmond to characterize a grou p of substances that are capable of liberating human perception from cultural conditioning, providing an op ening to the transcendent qualities of being human. Osmond claimed that LSD and similar drugs may give people insightful experiences that enable them to better understand themselves and their relationships with the world. Psychedelic substances have the potential to show mindmanifesting properties under appropriate internally and externally supported conditions. They can offer lucid insights into one’s psychological make-up and functioning. They are also capable of inducing a spectrum of inner experiences, sometimes
referred to as ‘religious’ or ‘mystical’. Another commonly used term for these substances is ‘hallucinogens’, although this synonym is viewed as controversial because of the implication that they somehow cause hallucinations, which they do very rarely. Most psychedelic substances produce visual alterations of perceived objects and pseudohallucinations which are understood by the subject to be ‘illusionary’ in character […]
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Brandt, S. D., & Passie, T. (2012). Research on psychedelic substances. Drug testing and analysis, 4(7-8), 539-542. https://dx.doi.org/10.1002/dta.1389
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Health status of ayahuasca users.

July 4, 2012 / Ayahuasca, Papers, Psychology, Publications / By / , , ,

Abstract

Ayahuasca is a psychedelic brew originally used for magico-religious purposes by Amerindian populations of the western Amazon Basin. Throughout the last four decades, the use of ayahuasca spread towards major cities in all regions of Brazil and abroad. This trend has raised concerns that regular use of this N,N-dimethyltryptamine- and harmala-alkaloid-containing tea may lead to mental and physical health problems associated typically with drug abuse. To further elucidate the mental and physical health of ayahuasca users, we conducted a literature search in the international medical PubMed database. Inclusion criteria were evaluation of any related effect of ayahuasca use that occurred after the resolution of acute effects of the brew. Fifteen publications were related to emotional, cognitive, and physical health of ayahuasca users. The accumulated data suggest that ayahuasca use is safe and may even be, under certain conditions, beneficial. However, methodological bias of the reviewed studies might have contributed to the preponderance of beneficial effects and to the few adverse effects reported. The data up to now do not appear to allow for definitive conclusions to be drawn on the effects of ayahuasca use on mental and physical health, but some studies point in the direction of beneficial effects. Additional studies are suggested to provide further clarification.

Barbosa, P. C. R., Mizumoto, S., Bogenschutz, M. P., & Strassman, R. J. (2012). Health status of ayahuasca users. Drug testing and analysis, 4(7-8), 601-609. https://dx.doi.org/10.1002/dta.1383
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Serotonergic Hallucinogens and Emerging Targets for Addiction Pharmacotherapies

June 1, 2012 / Mushrooms / Psilocybin, Neuroscience, Papers, Psychology, Publications, Substance Use Disorder / By /

Abstract

• Converging lines of evidence from pharmacologic, electrophysiologic, and behavioral
research in animals strongly suggest that activation of cortical 5-hydroxytryptamine-2A
receptors is the most critical step in initiating a cascade of biological events that accounts
for serotonergic hallucinogen (SH) psychoactive properties.
• Psilocybin produces hyperfrontality with divergent prefrontal–subcortical activation in such
a way as to increase cognitive and affective processing in the context of reduced gating
and reduced focus on external stimulus processing.
• In contrast to all other drugs of abuse, SHs are not considered to be capable of producing
sufficient reinforcing effects to cause dependence (addiction) syndromes.
• Given that SHs increase extracellular glutamate levels and activity in the prefrontal–
limbic circuitry, it is possible that a normalization in functional connectivity in this
network through a glutamate-dependent neuroplastic adaptation could produce an
anti-addictive effect.

Ross, S. (2012). Serotonergic hallucinogens and emerging targets for addiction pharmacotherapies. Psychiatric Clinics of North America, 35(2), 357-374. http://dx.doi.org/10.1016/j.psc.2012.04.002
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