Translated from our German original by AI. The German text was researched, written, and edited by the Psychedelia Foundation team and remains the authoritative version.
Psychedelic substances may owe their therapeutic effects to more than their immediate pharmacological action. A recent review by Gül Dölen and Makenzie L. Wilkinson in the Annual Review of Neuroscience presents a neurobiological model in which psychedelics temporarily increase the adult brain’s capacity for learning and adaptation.
The model centers on three interconnected processes. Psychedelics may reopen so-called critical periods, windows of time in which neural networks are especially receptive to experience-dependent change. They may also trigger metaplasticity, altering the brain’s ability to develop plasticity in the first place. Added to this is a remodeling of the extracellular matrix, the stabilizing scaffold that surrounds synapses.
The authors see in this a possible shared neurobiological mechanism across different psychedelics. A substantial part of their evidence, however, comes from preclinical studies, and how the three processes interact mechanistically has not yet been established. The authors therefore describe their proposal as a working model rather than a conclusively proven mechanism of action.
The model also challenges the long-dominant idea that mental disorders can be explained primarily as a neurochemical imbalance in need of correction. Dölen and Wilkinson propose a learning model instead: psychedelics may open a temporary window of heightened capacity for change, while context helps determine which processes of learning and adaptation actually take place.
Seen this way, the new neurobiological models could also explain why psychedelic therapy cannot be reduced to the drug effect alone, and why the experience itself and the therapeutic context play an important role.
