Psilocybin, a psychedelic compound, may help treat alcohol use disorder (AUD), but its brain effects in AUD are not well understood. In a placebo-controlled crossover study with healthy rats and a rat model of alcohol relapse, psilocybin broadly decreased functional connectivity across the brain while increasing connectivity between serotonin-related core regions and cortical areas. It also reduced connectivity within the default mode network (DMN), mirroring human findings. However, in rats with a history of alcohol relapse, this DMN hypoconnectivity was blunted, and the blunting correlated with relapse intensity. The results suggest that a standard psilocybin dose may be insufficient for severe AUD, a consideration for future clinical trials.
This article examines the treatment of mental illnesses with psychedelic substances from a psychotherapeutic perspective, focusing on the role of integrating psychedelic experiences. It asks how extraordinary experiences under the influence of psychedelics can be harnessed for psychotherapeutic progress. After an introductory overview of phases of psychedelic-assisted therapy (PAT), it describes a possibility for psychotherapeutically guided integration of psychedelic experiences using the example of treating treatment-resistant depressed patients with psilocybin in a clinical trial (EudraCT: 2019–003984–24; NCT04670081). The integration of psychedelic experiences into daily life is a scientifically little-studied but essential part of PAT. Evidence-based protocols should be developed to increase the efficacy and safety of therapy through integration methods. With the introduction of PAT into established healthcare systems, integration of psychedelic experiences is expected to become increasingly important.