OPEN Foundation

Anxiety disorders / PTSD

Dynamic coupling of whole-brain neuronal and neurotransmitter systems

Abstract

Remarkable progress has come from whole-brain models linking anatomy and function. Paradoxically, it is not clear how a neuronal dynamical system running in the fixed human anatomical connectome can give rise to the rich changes in the functional repertoire associated with human brain function, which is impossible to explain through long-term plasticity. Neuromodulation evolved to allow for such flexibility by dynamically updating the effectivity of the fixed anatomical connectivity. Here, we introduce a theoretical framework modeling the dynamical mutual coupling between the neuronal and neurotransmitter systems. We demonstrate that this framework is crucial to advance our understanding of whole-brain dynamics by bidirectional coupling of the two systems through combining multimodal neuroimaging data (diffusion magnetic resonance imaging [dMRI], functional magnetic resonance imaging [fMRI], and positron electron tomography [PET]) to explain the functional effects of specific serotoninergic receptor (5-HT2AR) stimulation with psilocybin in healthy humans. This advance provides an understanding of why psilocybin is showing considerable promise as a therapeutic intervention for neuropsychiatric disorders including depression, anxiety, and addiction. Overall, these insights demonstrate that the whole-brain mutual coupling between the neuronal and the neurotransmission systems is essential for understanding the remarkable flexibility of human brain function despite having to rely on fixed anatomical connectivity.

 
Kringelbach, M. L., Cruzat, J., Cabral, J., Knudsen, G. M., Carhart-Harris, R., Whybrow, P. C., … & Deco, G. (2020). Dynamic coupling of whole-brain neuronal and neurotransmitter systems. Proceedings of the National Academy of Sciences117(17), 9566-9576., https://doi.org/10.1073/pnas.1921475117
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Registered Clinical Trials Investigating Ketamine for Psychiatric Disorders

Abstract

As interest has grown in the potential psychiatric applications of ketamine, the number of registered clinical trials has grown substantially. Herein, we summarize and analyze clinical trials registered with ClinicalTrials.gov that assess the treatment of any psychiatric disorder with ketamine or ketamine enantiomers (e.g., S-ketamine, R-ketamine), with a focus on ongoing clinical trials. A ClinicalTrials.gov search on February 21, 2020 returned 140 registered trials. Frequency data was analyzed to determine the distribution of study designs. The majority of trials (70%) investigated the therapeutic effect of ketamine in mood disorders (unipolar: 60%, bipolar: 0.7%, both: 5.7%). Suicidal ideation (13.1%), post-traumatic stress disorder (5.4%), and obsessive-compulsive disorder (3.6%) were also investigated. Intravenous (IV) administration was the most common route with 87% of the studies using IV ketamine. Single-dose studies represented 50% of IV ketamine studies. Few studies were assessing maintenance treatment. Most studies were phase I or II with few definitive phase III trials registered. Given the large number of ongoing studies assessing psychiatric application of ketamine, researchers and relevant stakeholders should consider not only completed, published studies, but also ongoing registered studies in adjudicating the most relevant research questions. More definitive phase III trials and maintenance studies of IV ketamine for mood disorders are required, as numerous completed and ongoing studies have already assessed and demonstrated the proof-of-concept of acute antidepressant effects in phase I and II trials.
Peyrovian, B., McIntyre, R., Phan, L., Lui, L. M., Gill, H., Majeed, A., … & Rosenblat, J. D. (2020). Registered clinical trials investigating ketamine for psychiatric disorders. Journal of Psychiatric Research., https://doi.org/10.1016/j.jpsychires.2020.03.020
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Depression, Mindfulness, and Psilocybin: Possible Complementary Effects of Mindfulness Meditation and Psilocybin in the Treatment of Depression. A Review

Abstract

Depression is a major public health problem that affects approximately 4.4% of the global population. Since conventional pharmacotherapies and psychotherapies are only partially effective, as demonstrated by the number of patients failing to achieve remission, alternative treatments are needed. Mindfulness meditation (MM) and psilocybin represent two promising novel treatments that might even have complementary therapeutic effects when combined. Since the current literature is limited to theoretical and empirical underpinnings of either treatment alone, the present review aimed to identify possible complementary effects that may be relevant to the treatment of depression. To that end, the individual effects of MM and psilocybin, and their underlying working mechanisms, were compared on a non-exhaustive selection of six prominent psychological and biological processes that are well known to show impairments in patients suffering from major depression disorder, that is mood, executive functioning, social skills, neuroplasticity, core neural networks, and neuroendocrine and neuroimmunological levels. Based on predefined search strings used in two online databases (PubMed and Google Scholar) 1129 articles were identified. After screening title and abstract for relevance related to the question, 82 articles were retained and 11 were added after reference list search, resulting in 93 articles included in the review. Findings show that MM and psilocybin exert similar effects on mood, social skills, and neuroplasticity; different effects were found on executive functioning, neural core networks, and neuroendocrine and neuroimmune system markers. Potential mechanisms of MM’s effects are enhanced affective self-regulation through mental strategies, optimization of stress reactivity, and structural and functional adjustments of prefrontal and limbic areas; psilocybin’s effects might be established via attenuation of cognitive associations through deep personal insights, cognitive disinhibition, and global neural network disintegration. It is suggested that, when used in combination, MM and psilocybin could exert complementary effects by potentiating or prolonging mutual positive effects, for example, MM potentially facilitating psilocybin-induced peak experiences. Future placebo-controlled double-blind randomized trials focusing on psilocybin-assisted mindfulness-based therapy will provide knowledge about whether the proposed combination of therapies maximizes their efficacy in the treatment of depression or depressive symptomatology.

Heuschkel, K., & Kuypers, K. P. (2020). Depression, Mindfulness, and Psilocybin: Possible Complementary Effects of Mindfulness Meditation and Psilocybin in the Treatment of Depression. A Review. Frontiers in Psychiatry11., https://doi.org/10.3389/fpsyt.2020.00224
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Long-term effects of psychedelic drugs: A systematic review

Abstract

Research into the basic effects and therapeutic applications of psychedelic drugs has grown considerably in recent years. Yet, pressing questions remain regarding the substances’ lasting effects. Although individual studies have begun monitoring sustained changes, no study to-date has synthesized this information. Therefore, this systematic review aims to fill this important gap in the literature by synthesizing results from 34 contemporary experimental studies which included classic psychedelics, human subjects, and follow-up latencies of at least two weeks. The bulk of this work was published in the last five years, with psilocybin being the most frequently administered drug. Enduring changes in personality/attitudes, depression, spirituality, anxiety, wellbeing, substance misuse, meditative practices, and mindfulness were documented. Mystical experiences, connectedness, emotional breakthrough, and increased neural entropy were related to these long-term changes in psychological functioning. Finally, with proper screening, preparation, supervision, and integration, limited aversive side effects were noted by study participants. Future researchers should focus on including larger and more diverse samples, lengthier longitudinal designs, stronger control conditions, and standardized dosages.

Aday, J. S., Mitzkovitz, C. M., Bloesch, E. K., Davoli, C. C., & Davis, A. K. (2020). Long-term effects of psychedelic drugs: A systematic review. Neuroscience & Biobehavioral Reviews., 10.1016/j.neubiorev.2020.03.017
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Reviewing the Potential of Psychedelics for the Treatment of PTSD.

Abstract

There are few medications with demonstrated efficacy for the treatment of posttraumatic stress disorder (PTSD). Treatment guidelines have unequivocally designated psychotherapy as a first line treatment for PTSD. Yet, even after psychotherapy, PTSD often remains a chronic illness, with high rates of psychiatric and medical comorbidity. Meanwhile, the search and development of drugs with new mechanisms of action has stalled. Therefore, there is an urgent need to explore not just novel compounds, but novel approaches for the treatment of PTSD. A promising new approach involves the use of psychedelic drugs. Within the past few years, two psychedelics have received breakthrough designations for psychiatric indications from the US Food and Drug Administration, and several psychedelics are currently being investigated for the treatment of PTSD. This review discusses four types of compounds: 3,4-methylenedioxymethamphetamine (MDMA), ketamine, classical psychedelics (e.g. psilocybin and LSD) and cannabinoids. We describe the therapeutic rationale, the setting in which they are being administered, and their current state of evidence in the treatment of PTSD. Each compound provides unique qualities for the treatment of PTSD, from their use to rapidly target symptoms, to their use as adjuncts to facilitate psychotherapeutic treatments. Several questions are formulated that outline an agenda for future research.
Krediet, E., Bostoen, T., Breeksema, J., van Schagen, A., Passie, T., & Vermetten, E. (2020). Reviewing the Potential of Psychedelics for the Treatment of PTSD. International Journal of Neuropsychopharmacology., https://doi.org/10.1093/ijnp/pyaa018
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Psilocybin Therapeutic Research: The Present and Future Paradigm

Abstract

Psilocybin, an active component in “magic mushroom”, may have the potential to meet the therapeutic needs for a number of indications without the addictiveness and overdose risk of other mind-altering drugs, such as cocaine, heroin, alcohol, methamphetamine, and so forth. The need for new therapies is urgent because addiction, overdose, and suicide deaths have risen throughout the United States and around the world. Anecdotal and contemporary pharmacological reports have provided some indication about the therapeutic use of psilocybin for the treatment of mental health disorders such as major depressive disorder and addiction disorders. In this Viewpoint, I summarize the current state of psilocybin therapeutic research and attempt to provide some insight into future directions on which the scientific community may wish to focus.

Kargbo, R. B. (2020). Psilocybin Therapeutic Research: The Present and Future Paradigm. ACS Medicinal Chemistry Letters11(4), 399-402.; 10.1021/acsmedchemlett.0c00048

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Psychedelics and Dying Care: A Historical Look at the Relationship Between Psychedelics and Palliative Care

Abstract

This article examines the historical relationship between psychedelics and palliative care. Historians have contributed to a growing field of studies about how psychedelics have been used in the past, but much of that scholarship focused on interrogating questions of legitimacy or proving that psychedelics had therapeutic potential. Palliative care had not yet developed as medical sub-specialty, more often leaving dying care on the margins of modern, pharmaceutical-based treatments. As psychedelic researchers in the 1950s began exploring different applications for psychoactive substances such as LSD and mescaline, however, dying care came into clearer focus as a potential avenue for psychedelics. Before that application gained momentum in clinical or philosophical discussions, psychedelics were criminalized and some of those early discussions were lost. This article looks back at historical discussions about LSD’s potential for easing the anxiety associated with dying, and considers how those early conversations might offer insights into today’s more articulated discussions about psychedelics in palliative care.
Dyck, E. (2019). Psychedelics and dying care: A historical look at the relationship between psychedelics and palliative care. Journal of psychoactive drugs51(2), 102-107., https://doi.org/10.1080/02791072.2019.1581308
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Posttraumatic Growth After MDMA-Assisted Psychotherapy for Posttraumatic Stress Disorder

Abstract

3,4-Methylenedioxymethamphetamine (MDMA)-assisted psychotherapy for posttraumatic stress disorder (PTSD) has been shown to significantly reduce clinical symptomatology, but posttraumatic growth (PTG), which consists of positive changes in self-perception, interpersonal relationships, or philosophy of life, has not been studied with this treatment. Participant data (n = 60) were pooled from three Phase 2 clinical studies employing triple-blind crossover designs. Participants were required to meet DSM-IV-R criteria for PTSD with a score higher than 50 on the Clinician-Administered PTSD Scale (CAPS-IV) as well as previous inadequate response to pharmacological and/or psychotherapeutic treatment. Data were aggregated into two groups: an active MDMA dose group (75-125 mg of MDMA; n = 45) or placebo/active control (0-40 mg of MDMA; n = 15). Measures included the Posttraumatic Growth Inventory (PTGI) and the CAPS-IV, which were administered at baseline, primary endpoint, treatment exit, and 12-month follow-up. At primary endpoint, the MDMA group demonstrated more PTG, Hedges’ g = 1.14, 95% CI [0.49, 1.78], p < .001; and a larger reduction in PTSD symptom severity, Hedges’ g = 0.88, 95% CI [-0.28, 1.50], p < .001, relative to the control group. Relative to baseline, at the 12-month follow-up, within-subject PTG was higher, p < .001; PTSD symptom severity scores were lower, p < .001; and two-thirds of participants (67.2%) no longer met criteria for PTSD. MDMA-assisted psychotherapy for PTSD resulted in PTG and clinical symptom reductions of large-magnitude effect sizes. Results suggest that PTG may provide a new mechanism of action warranting further study.

Gorman, I., Belser, A. B., Jerome, L., Hennigan, C., Shechet, B., Hamilton, S., Yazar-Klosinski, B., Emerson, A., & Feduccia, A. A. (2020). Posttraumatic Growth After MDMA-Assisted Psychotherapy for Posttraumatic Stress Disorder. Journal of traumatic stress, 33(2), 161–170. https://doi.org/10.1002/jts.22479

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Posttraumatic Growth After MDMA‐Assisted Psychotherapy for Posttraumatic Stress Disorder

Abstract

3,4‐Methylenedioxymethamphetamine (MDMA)–assisted psychotherapy for posttraumatic stress disorder (PTSD) has been shown to significantly reduce clinical symptomatology, but posttraumatic growth (PTG), which consists of positive changes in self‐perception, interpersonal relationships, or philosophy of life, has not been studied with this treatment. Participant data (n = 60) were pooled from three Phase 2 clinical studies employing triple‐blind crossover designs. Participants were required to meet DSM‐IV‐R criteria for PTSD with a score higher than 50 on the Clinician‐Administered PTSD Scale (CAPS‐IV) as well as previous inadequate response to pharmacological and/or psychotherapeutic treatment. Data were aggregated into two groups: an active MDMA dose group (75–125 mg of MDMA; n = 45) or placebo/active control (0–40 mg of MDMA; n = 15). Measures included the Posttraumatic Growth Inventory (PTGI) and the CAPS‐IV, which were administered at baseline, primary endpoint, treatment exit, and 12‐month follow‐up. At primary endpoint, the MDMA group demonstrated more PTG, Hedges’ g = 1.14, 95% CI [0.49, 1.78], p < .001; and a larger reduction in PTSD symptom severity, Hedges’ g = 0.88, 95% CI [−0.28, 1.50], p < .001, relative to the control group. Relative to baseline, at the 12‐month follow‐up, within‐subject PTG was higher, p < .001; PTSD symptom severity scores were lower, p < .001; and two‐thirds of participants (67.2%) no longer met criteria for PTSD. MDMA‐assisted psychotherapy for PTSD resulted in PTG and clinical symptom reductions of large‐magnitude effect sizes. Results suggest that PTG may provide a new mechanism of action warranting further study.
Gorman, I., Belser, A. B., Jerome, L., Hennigan, C., Shechet, B., Hamilton, S., … & Feduccia, A. A. (2020). Posttraumatic Growth After MDMA‐Assisted Psychotherapy for Posttraumatic Stress Disorder. Journal of Traumatic Stress., https://doi.org/10.1002/jts.22479

A review of emerging therapeutic potential of psychedelic drugs in the treatment of psychiatric illnesses

Abstract

Though there was initial interest in the use of psychedelic drugs for psychiatric treatment, bad outcomes and subsequent passage of the Substance Act of 1970, which placed psychedelic drugs in the Schedule I category, significantly limited potential progress. More recently, however, there has been renewal in interest and promise of psychedelic research. The purpose of this review is to highlight contemporary human studies on the use of select psychedelic drugs, such as psilocybin, LSD, MDMA and ayahuasca, in the treatment of various psychiatric illnesses, including but not limited to treatment-resistant depression, post-traumatic stress disorder, end-of-life anxiety, and substance use disorders. The safety and efficacy as reported from human and animal studies will also be discussed. Accumulated research to date has suggested the potential for psychedelics to emerge as breakthrough therapies for psychiatric conditions refractory to conventional treatments. However, given the unique history and high potential for misuse with popular distribution, special care and considerations must be undertaken to safeguard their use as viable medical treatments rather than drugs of abuse.

Chi, T., & Gold, J. A. (2020). A review of emerging therapeutic potential of psychedelic drugs in the treatment of psychiatric illnesses. Journal of the Neurological Sciences, 116715., 10.1016/j.jns.2020.116715
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14 May - Psychedelics & Psychosis with Phoebe Friesen and Dirk Corstens

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