Serotonin, Predictive Processing and Psychedelics

A commentary argues that Letheby's use of Predictive Processing to explain psychedelic therapy may lack genuine explanatory power, making his account unwarranted. The author motivates this concern and sketches an alternative interpretation of psychedelic therapy within the Reinforcement Learning framework.

Study at a glance

Abstract

Letheby’s "Philosophy of Psychedelics" relies on Predictive Processing to try and find unifying explanations relevant to understanding how serotonergic psychedelics work in psychiatric therapy, what subjective experiences are associated with their use and whether such experiences are epistemically defective. But if Predictive Processing lacks genuinely explanatory unifying power, Letheby’s account of psychedelic therapy risks being unwarranted. In this commentary, I motivate this worry and sketch an alternative interpretation of psychedelic therapy within the Reinforcement Learning framework.