OPEN Foundation

Day: 13 January 2020

Psilocybin Induces Time-Dependent Changes in Global Functional Connectivity

Abstract

Background

The use of psilocybin in scientific and experimental clinical contexts has triggered renewed interest in the mechanism of action of psychedelics. However, its time-dependent systems-level neurobiology remains sparsely investigated in humans.

Methods

We conducted a double-blind, randomized, counterbalanced, crossover study comprising 23 healthy human participants who received placebo and 0.2 mg/kg of psilocybin orally on 2 different test days. Participants underwent magnetic resonance imaging at 3 time points between administration and peak effects: 20 minutes, 40 minutes, and 70 minutes after administration. Resting-state functional connectivity was quantified via a data-driven global brain connectivity method and compared with cortical gene expression maps.

Results

Psilocybin reduced associative, but concurrently increased sensory, brain-wide connectivity. This pattern emerged over time from administration to peak effects. Furthermore, we showed that baseline connectivity is associated with the extent of psilocybin-induced changes in functional connectivity. Lastly, psilocybin-induced changes correlated in a time-dependent manner with spatial gene expression patterns of the 5-HT2A (5-hydroxytryptamine 2A) and 5-HT1A (5-hydroxytryptamine 1A) receptors.

Conclusions

These results suggest that the integration of functional connectivity in sensory regions and the disintegration in associative regions may underlie the psychedelic state and pinpoint the critical role of the serotonin 2A and 1A receptor systems. Furthermore, baseline connectivity may represent a predictive marker of the magnitude of changes induced by psilocybin and may therefore contribute to a personalized medicine approach within the potential framework of psychedelic treatment.

Preller, K. H., Duerler, P., Burt, J. B., Ji, J. L., Adkinson, B., Stämpfli, P., … & Anticevic, A. (2020). Psilocybin induces time-dependent changes in global functional connectivity: Psi-induced changes in brain connectivity. Biological Psychiatry., 10.1016/j.biopsych.2019.12.027
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In vivo effects of 3,4-methylenedioxymethamphetamine (MDMA) and its deuterated form in rodents: Drug discrimination and thermoregulation.

Abstract

BACKGROUND:

Recent clinical studies support the use of 3,4-methylenedioxymethamphetamine (MDMA) as an adjunct treatment for posttraumatic stress disorder (PTSD). Despite these promising findings, MDMA administration in controlled settings can increase blood pressure, heart rate, and body temperature. Previous studies indicate thatO-demethylated metabolites of MDMA contribute to its adverse effects. As such, limiting the conversion of MDMA to reactive metabolites may mitigate some of its adverse effects and potentially improve its safety profile for therapeutic use.

METHODS:

We compared the interoceptive and hyperthermic effects of a deuterium-substituted form of MDMA (d2-MDMA) to MDMA using rodent drug discrimination and biotelemetry procedures, respectively.

RESULTS:

Compared to MDMA, d2-MDMA produced full substitution for a 1.5 mg/kg MDMA training stimulus with equal potency and effectiveness in the drug discrimination experiment. In addition, d2-MDMA produced increases in body temperature that were shorter-lasting and of lower magnitude compared to equivalent doses of MDMA. Last, d2-MDMA and MDMA were equally effective in reversing the hypothermic effects of the selective 5-HT2A/2C antagonist ketanserin.

CONCLUSION:

These findings indicate that deuterium substitution of hydrogen at the methylenedioxy ring moiety does not impact MDMA’s interoceptive effects, and compared to MDMA, d2-MDMA has less potential for producing hyperthermic effects and likely has similar pharmacodynamic properties. Given that d2-MDMA produces less adverse effects than MDMA, but retains similar desirable effects that are thought to relate to the effective treatment of PTSD, additional investigations into its effects on cardiovascular functioning and pharmacokinetic properties are warranted.

Berquist, M. D., Leth-Petersen, S., Kristensen, J. L., & Fantegrossi, W. E. (2020). In vivo effects of 3, 4-methylenedioxymethamphetamine (MDMA) and its deuterated form in rodents: drug discrimination and thermoregulation. Drug and Alcohol Dependence, 107850., 10.1016/j.drugalcdep.2020.107850
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Antidepressant and neurocognitive effects of serial ketamine administration versus ECT in depressed patients

Abstract

BACKGROUND:

While electroconvulsive therapy (ECT) is considered the gold standard for acute treatment of patients with otherwise treatment-resistant depression, ketamine has recently emerged as a fast-acting treatment alternative for these patients. Efficacy and onset of action are currently among the main factors that influence clinical decision making, however, the effect of these treatments on cognitive functions should also be a crucial point, given that cognitive impairment in depression is strongly related to disease burden and functional recovery. ECT is known to induce transient cognitive impairment, while little is known about ketamine’s impact on cognition. This study therefore aims to compare ECT and serial ketamine administration not only with regard to their antidepressant efficacy but also to acute neurocognitive effects.

METHODS:

Fifty patients suffering from depression were treated with either serial ketamine infusions or ECT. Depression severity and cognitive functions were assessed before, during, and after treatment.

RESULTS:

ECT and ketamine administration were equally effective, however, the antidepressant effects of ketamine occurred faster. Ketamine improved neurocognitive functioning, especially attention and executive functions, whereas ECT was related to a small overall decrease in cognitive performance.

CONCLUSIONS:

Due to its pro-cognitive effects and faster antidepressant effect, serial ketamine administration might be a more favorable short-term treatment option than ECT.

LIMITATIONS:

As this research employed a naturalistic study design, patients were not systematically randomized, there was no control group and patients received concurrent and partially changing medications during treatment.

CLINICAL TRIALS REGISTRATION:

Functional and Metabolic Changes in the Course of Antidepressive Treatment, https://clinicaltrials.gov/ct2/show/NCT02099630NCT02099630.

Basso, L., Bönke, L., Aust, S., Gärtner, M., Heuser-Collier, I., Otte, C., … & Grimm, S. (2020). Antidepressant and neurocognitive effects of serial ketamine administration versus ECT in depressed patients. Journal of Psychiatric Research.,  10.1016/j.jpsychires.2020.01.002

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A Dangerous Method? Psychedelic Therapy at Modum Bad, Norway, 1961-76

Abstract

After many years of disregard, the use of psychedelic drugs in psychiatric treatment has re-emerged in recent years. The prospect that psychedelics may again be integrated into mainstream psychiatry has aroused interest in long-forgotten research and experience from the previous phase of psychedelic therapy, which lasted from the late 1940s to the 1970s. This article will discuss one large-scale psychedelic therapy programme at Modum Bad Nervesanatorium, a psychiatric clinic which treated 379 inpatients with psychedelic drugs during the years 1961-76. The psychiatrists there initially regarded the psychedelic treatment as efficacious and without serious negative reactions, but reports of long-term harm have since surfaced. This article discusses how insights from Modum Bad might benefit the new generation of psychedelic treatment efforts.
Johnstad, P. G. (2020). A dangerous method? Psychedelic therapy at Modum Bad, Norway, 1961–76. History of Psychiatry31(2), 217-226., https://doi.org/10.1177%2F0957154X19894537
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30 April - Q&A with Rick Strassman

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