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Phenomenology

LSD Increases Primary Process Thinking via Serotonin 2A Receptor Activation

November 8, 2017 / LSD, Papers, Phenomenology, Philosophy, Psychiatry, Psychopharmacology, Publications / By / , , , , , ,

Abstract

Rationale: Stimulation of serotonin 2A (5-HT2A) receptors by lysergic acid diethylamide (LSD) and related compounds such as psilocybin has previously been shown to increase primary process thinking – an ontologically and evolutionary early, implicit, associative, and automatic mode of thinking which is typically occurring during altered states of consciousness such as dreaming. However, it is still largely unknown whether LSD induces primary process thinking under placebo-controlled, standardized experimental conditions and whether these effects are related to subjective experience and 5-HT2A receptor activation. Therefore, this study aimed to test the hypotheses that LSD increases primary process thinking and that primary process thinking depends on 5-HT2A receptor activation and is related to subjective drug effects.

Methods: Twenty-five healthy subjects performed an audio-recorded mental imagery task 7 h after drug administration during three drug conditions: placebo, LSD (100 mcg orally) and LSD together with the 5-HT2A receptor antagonist ketanserin (40 mg orally). The main outcome variable in this study was primary index (PI), a formal measure of primary process thinking in the imagery reports. State of consciousness was evaluated using the Altered State of Consciousness (5D-ASC) rating scale.

Results: LSD, compared with placebo, significantly increased primary index (p < 0.001, Bonferroni-corrected). The LSD-induced increase in primary index was positively correlated with LSD-induced disembodiment (p < 0.05, Bonferroni-corrected), and blissful state (p < 0.05, Bonferroni-corrected) on the 5D-ASC. Both LSD-induced increases in primary index and changes in state of consciousness were fully blocked by ketanserin.

Conclusion: LSD induces primary process thinking via activation of 5-HT2A receptors and in relation to disembodiment and blissful state. Primary process thinking appears to crucially organize inner experiences during both dreams and psychedelic states of consciousness.

Kraehenmann, R., Pokorny, D., Aicher, H., Preller, K. H., Pokorny, T., Bosch, O. G., … & Vollenweider, F. X. (2017). LSD Increases Primary Process Thinking via Serotonin 2A Receptor Activation. Frontiers in Pharmacology, 8, 814. 10.3389/fphar.2017.00814
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Double-blind comparison of the two hallucinogens psilocybin and dextromethorphan: similarities and differences in subjective experiences

November 7, 2017 / Mushrooms / Psilocybin, Other substances, Papers, Phenomenology, Psychology, Publications / By / , , ,

Abstract

Rationale

Although psilocybin and dextromethorphan (DXM) are hallucinogens, they have different receptor mechanisms of action and have not been directly compared.

Objective

This study compared subjective, behavioral, and physiological effects of psilocybin and dextromethorphan under conditions that minimized expectancy effects.

Methods

Single, acute oral doses of psilocybin (10, 20, 30 mg/70 kg), DXM (400 mg/70 kg), and placebo were administered under double-blind conditions to 20 healthy participants with histories of hallucinogen use. Instructions to participants and staff minimized expectancy effects. Various subjective, behavioral, and physiological effects were assessed after drug administration.

Results

High doses of both drugs produced similar increases in participant ratings of peak overall drug effect strength, with similar times to maximal effect and time-course. Psilocybin produced orderly dose-related increases on most participant-rated subjective measures previously shown sensitive to hallucinogens. DXM produced increases on most of these same measures. However, the high dose of psilocybin produced significantly greater and more diverse visual effects than DXM including greater movement and more frequent, brighter, distinctive, and complex (including textured and kaleidoscopic) images and visions. Compared to DXM, psilocybin also produced significantly greater mystical-type and psychologically insightful experiences and greater absorption in music. In contrast, DXM produced larger effects than psilocybin on measures of disembodiment, nausea/emesis, and light-headedness. Both drugs increased systolic blood pressure, heart rate, and pupil dilation and decreased psychomotor performance and balance.

Conclusions

Psilocybin and DXM produced similar profiles of subjective experiences, with psilocybin producing relatively greater visual, mystical-type, insightful, and musical experiences, and DXM producing greater disembodiment.

Carbonaro, T. M., Johnson, M. W., Hurwitz, E., & Griffiths, R. R. (2017). Double-blind comparison of the two hallucinogens psilocybin and dextromethorphan: similarities and differences in subjective experiences. Psychopharmacology, 1-14. 10.1007/s00213-017-4769-4
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LSD modulates effective connectivity and neural adaptation mechanisms in an auditory oddball paradigm

October 31, 2017 / LSD, Neuroscience, Other subjects, Papers, Phenomenology, Psychology, Psychopharmacology, Publications / By / , , , , , ,

Abstract

Under the predictive coding framework, perceptual learning and inference are dependent on the interaction between top-down predictions and bottom-up sensory signals both between and within regions in a network. However, how such feedback and feedforward connections are modulated in the state induced by lysergic acid diethylamide (LSD) is poorly understood. In this study, an auditory oddball paradigm was presented to healthy participants (16 males, 4 female) under LSD and placebo, and brain activity was recorded using magnetoencephalography (MEG). Scalp level Event Related Fields (ERF) revealed reduced neural adaptation to familiar stimuli, and a blunted neural ‘surprise’ response to novel stimuli in the LSD condition. Dynamic causal modelling revealed that both the presentation of novel stimuli and LSD modulate backward extrinsic connectivity within a task-activated fronto-temporal network, as well as intrinsic connectivity in the primary auditory cortex. These findings show consistencies with those of previous studies of schizophrenia and ketamine but also studies of reduced consciousness – suggesting that rather than being a marker of conscious level per se, backward connectivity may index modulations of perceptual learning common to a variety of altered states of consciousness, perhaps united by a shared altered sensitivity to environmental stimuli. Since recent evidence suggests that the psychedelic state may correspond to a heightened ‘level’ of consciousness with respect to the normal waking state, our data warrant a re-examination of the top-down hypotheses of conscious level and suggest that several altered states may feature this specific biophysical effector.
Timmermann, C., Spriggs, M. J., Kaelen, M., Leech, R., Nutt, D. J., Moran, R. J., … & Muthukumaraswamy, S. D. (2017). LSD modulates effective connectivity and neural adaptation mechanisms in an auditory oddball paradigm. Neuropharmacology. 10.1016/j.neuropharm.2017.10.039
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A phenomenological analysis of the subjective experience elicited by ibogaine in the context of a drug dependence treatment

August 29, 2017 / Addiction, Iboga / Ibogaine, Papers, Phenomenology, Psychology, Publications / By / , , , , ,

Abstract

Objective

This report documents the phenomenology of the subjective experiences of 22 patients with substance-related disorders who were involved in a treatment combining cognitive–behavioral therapy and hospital sessions with ibogaine in Brazil.

Methods

Participants underwent a one-to-one semi-structured interview exploring the subjective effects of ibogaine. We employed interpretative phenomenological analysis to identify relevant phenomenological categories, including physical sensations, perceptual (visual, auditory, and olfactory), emotional, cognitive, and spiritual. Participants also compared ibogaine with other drugs used in life, including psychedelics like ayahuasca, psilocybin mushrooms, and lysergic acid diethylamide.

Results

The findings reveal that the subjective experience with ibogaine has similarities with other psychedelic substances, but also important differences. These include very strong and unpleasant physical effects as well as, at least in this patient population, a very difficult and challenging experience.

Conclusions

Overall, the descriptions involve heightened memory retrieval, specially related to drug abuse and the perception of one’s own future with or without drug use. Strong perceptual phenomena, especially dreamlike visions, were commonly reported. Based on Revonsuo’s evolutionary hypothesis for the function of dreams and of previous suggestions that ibogaine has oneiric properties, we suggest the subjective experience of drug-dependent patients elicited by ibogaine may be framed as simulations of threat and danger.

Schenberg, E. E., de Castro Comis, M. A., Alexandre, J. F. M., Tófoli, L. F., Chaves, B. D. R., & da Silveira, D. X. (2017). A phenomenological analysis of the subjective experience elicited by ibogaine in the context of a drug dependence treatment. Journal of Psychedelic Studies, (0), 1-10. 10.1556/2054.01.2017.007
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The hyperassociative mind: The psychedelic experience and Merleau-Ponty’s “wild being”

July 20, 2017 / Cacti / Mescaline, Papers, Phenomenology, Philosophy / By / , , , ,

Abstract

Purpose

In contemporary phenomenology, Dieter Lohmar has suggested that the new task of phenomenological research is to analyze the “alternative representational systems” of fantasy. In line with this program, we propose that psychedelic experience could also be suitable subject to this project subsumed under the wider category of fantasy activity. The aim of this paper is to show that psychedelic experiences offer a favorable situation to study the imagination.

Method

The paper applies the conceptual framework of the late Merleau-Ponty, developed in The Visible and the Invisible, using his mescaline analyses which have been elaborated in The Phenomenology of Perception.

Results

We demonstrate that psychedelic visions and emotional states can be discussed within the Merleau-Pontian framework of “wild world.” From the viewpoint of phenomenology, we suggest that psychedelic visions represent an ongoing sense-making and Gestalt-formation process in which the role of the elaborative activity of the subject is crucial. These – often unsettling – visions show the basic volatility and ambiguity of perception and fantasy, which also sheds light to the hidden schemes of perception, thinking, and emotion of normal consciousness.

Conclusions

Freud claimed that dreams are “the royal road” to the unconscious. In an analogous manner, while dreams were the primary psychoscope to the unconscious of psychoanalysis, in contemporary phenomenology psychedelic experiences may show a possible way to an another kind of unconscious, the phenomenological unconscious. This unconscious comprises the hidden schemes and basic affective emotional attitudes of the knowing subject.

Szummer, C., Horváth, L., SzabÓ, A., Frecska, E., & OrzÓi, K. (2017). The hyperassociative mind: The psychedelic experience and Merleau-Ponty’s “wild being”. Journal of Psychedelic Studies, (0), 1-10. 10.1556/2054.01.2017.006
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Patients’ Accounts of Increased “Connectedness” and “Acceptance” After Psilocybin for Treatment-Resistant Depression

June 19, 2017 / Depression, Mushrooms / Psilocybin, Papers, Phenomenology, Psychiatry, Psychology, Psychotherapy, Publications / By / , , , ,

Abstract

Objective:

To identify patients’ perceptions of the value of psilocybin as a treatment for depression.

Method:

Twenty patients enrolled in an open-label trial of psilocybin for treatment-resistant depression participated in a semistructured interview at 6-month follow-up. Thematic analysis was used to identify patients’ experiences of the treatment and how it compared with previous treatments.

Results:

Two main change processes were identified in relation to the treatment. The first concerned change from disconnection (from self, others, and world) to connection, and the second concerned change from avoidance (of emotion) to acceptance. A third theme concerned comparison between psilocybin and conventional treatments. Patients reported that medications and some short-term talking therapies tended to reinforce their sense of disconnection and avoidance, whereas treatment with psilocybin encouraged connection and acceptance.

Conclusion:

These results suggest that psilocybin treatment for depression may work via paradigmatically novel means, antithetical to antidepressant medications, and some short-term talking therapies.
Watts, R., Day, C., Krzanowski, J., Nutt, D., & Carhart-Harris, R. (2017). Patients’ Accounts of Increased “Connectedness” and “Acceptance” After Psilocybin for Treatment-Resistant Depression. Journal of Humanistic Psychology, 0022167817709585.

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Dreams and psychedelics: neurophenomenological comparison and therapeutic implications

June 18, 2017 / Ayahuasca, LSD, Mushrooms / Psilocybin, Papers, Phenomenology, Psychology, Publications / By /

Abstract

A resurgence of neurobiological and clinical research is currently underway into the therapeutic potential of serotonergic or ‘classical’ psychedelics, such as the prototypical psychedelic drug lysergic acid diethylamide (LSD), psilocybin (4-phosphoryloxy-N,N-dimethyltryptamine), and ayahuasca – a betacarboline- and dimethyltryptamine (DMT)-containing Amazonian beverage. However, the mechanisms of therapeutic action are still not fully explained. Given that an altered state of consciousness is a common denominator that characterizes all classical psychedelics and given that both rapid eye movement sleep (REMS) and psychedelics modulate perception, mental imagery, emotion activation, fear memory extinction, and sense of self and body, in the present article, these two states of consciousness are systematically compared, and therapeutically relevant conclusions are drawn based on available evidence.
Kraehenmann, R. (2017). Dreams and psychedelics: neurophenomenological comparison and therapeutic implications. Current neuropharmacology. 10.2174/1573413713666170619092629
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Cancer at the Dinner Table: Experiences of Psilocybin-Assisted Psychotherapy for the Treatment of Cancer-Related Distress

June 14, 2017 / Anxiety disorders / PTSD, Depression, Mushrooms / Psilocybin, Mystical experiences, Papers, Phenomenology, Psychiatry, Psychology, Psychotherapy, Publications, Spirituality / By / , , , , , ,

Abstract

Recent randomized controlled trials of psilocybin-assisted psychotherapy for patients with cancer suggest that this treatment results in large-magnitude reductions in anxiety and depression as well as improvements in attitudes toward disease progression and death, quality of life, and spirituality. To better understand these findings, we sought to identify psychological mechanisms of action using qualitative methods to study patient experiences in psilocybin-assisted psychotherapy. Semistructured interviews were conducted with 13 adult participants with clinically elevated anxiety associated with a cancer diagnosis who received a single dose of psilocybin under close clinical supervision. Transcribed interviews were analyzed using interpretative phenomenological analysis, which resulted in 10 themes, focused specifically on cancer, death and dying, and healing narratives. Participants spoke to the anxiety and trauma related to cancer, and perceived lack of available emotional support. Participants described the immersive and distressing effects of the psilocybin session, which led to reconciliations with death, an acknowledgment of cancer’s place in life, and emotional uncoupling from cancer. Participants made spiritual or religious interpretations of their experience, and the psilocybin therapy helped facilitate a felt reconnection to life, a reclaiming of presence, and greater confidence in the face of cancer recurrence. Implications for theory and clinical treatment are discussed.
Swift, T. C., Belser, A. B., Agin-Liebes, G., Devenot, N., Terrana, S., Friedman, H. L., … & Ross, S. (2017). Cancer at the Dinner Table: Experiences of Psilocybin-Assisted Psychotherapy for the Treatment of Cancer-Related Distress. Journal of Humanistic Psychology, 0022167817715966.
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Looking for the Self: Phenomenology, Neurophysiology and Philosophical Significance of Drug-induced Ego Dissolution

May 23, 2017 / Consciousness, LSD, Mushrooms / Psilocybin, Mystical experiences, Neuroscience, Other substances, Papers, Personality, Phenomenology, Philosophy, Psychology, Psychopharmacology, Publications, Spirituality / By /

Abstract

There is converging evidence that high doses of hallucinogenic drugs can produce significant alterations of self-experience, described as the dissolution of the sense of self and the loss of boundaries between self and world. This article discusses the relevance of this phenomenon, known as “drug-induced ego dissolution (DIED)”, for cognitive neuroscience, psychology and philosophy of mind. Data from self-report questionnaires suggest that three neuropharmacological classes of drugs can induce ego dissolution: classical psychedelics, dissociative anesthetics and agonists of the kappa opioid receptor (KOR). While these substances act on different neurotransmitter receptors, they all produce strong subjective effects that can be compared to the symptoms of acute psychosis, including ego dissolution. It has been suggested that neuroimaging of DIED can indirectly shed light on the neural correlates of the self. While this line of inquiry is promising, its results must be interpreted with caution. First, neural correlates of ego dissolution might reveal the necessary neurophysiological conditions for the maintenance of the sense of self, but it is more doubtful that this method can reveal its minimally sufficient conditions. Second, it is necessary to define the relevant notion of self at play in the phenomenon of DIED. This article suggests that DIED consists in the disruption of subpersonal processes underlying the “minimal” or “embodied” self, i.e., the basic experience of being a self rooted in multimodal integration of self-related stimuli. This hypothesis is consistent with Bayesian models of phenomenal selfhood, according to which the subjective structure of conscious experience ultimately results from the optimization of predictions in perception and action. Finally, it is argued that DIED is also of particular interest for philosophy of mind. On the one hand, it challenges theories according to which consciousness always involves self-awareness. On the other hand, it suggests that ordinary conscious experience might involve a minimal kind of self-awareness rooted in multisensory processing, which is what appears to fade away during DIED.
Millière, R. (2017). Looking For The Self: Phenomenology, Neurophysiology and Philosophical Significance of Drug-induced Ego Dissolution. Frontiers in Human Neuroscience, 11. 10.3389/fnhum.2017.00245
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Increased spontaneous MEG signal diversity for psychoactive doses of ketamine, LSD and psilocybin

April 19, 2017 / Consciousness, Ketamine, LSD, Mushrooms / Psilocybin, Papers, Phenomenology, Psychology, Publications / By / , , , ,

Abstract

What is the level of consciousness of the psychedelic state? Empirically, measures of neural signal diversity such as entropy and Lempel-Ziv (LZ) complexity score higher for wakeful rest than for states with lower conscious level like propofol-induced anesthesia. Here we compute these measures for spontaneous magnetoencephalographic (MEG) signals from humans during altered states of consciousness induced by three psychedelic substances: psilocybin, ketamine and LSD. For all three, we find reliably higher spontaneous signal diversity, even when controlling for spectral changes. This increase is most pronounced for the single-channel LZ complexity measure, and hence for temporal, as opposed to spatial, signal diversity. We also uncover selective correlations between changes in signal diversity and phenomenological reports of the intensity of psychedelic experience. This is the first time that these measures have been applied to the psychedelic state and, crucially, that they have yielded values exceeding those of normal waking consciousness. These findings suggest that the sustained occurrence of psychedelic phenomenology constitutes an elevated level of consciousness – as measured by neural signal diversity.
Schartner, M. M., Carhart-Harris, R. L., Barrett, A. B., Seth, A. K., & Muthukumaraswamy, S. D. (2017). Increased spontaneous MEG signal diversity for psychoactive doses of ketamine, LSD and psilocybin. Scientific Reports, 7. 10.1038/srep46421
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