How Psychedelics Modulate Multiple Memory Mechanisms in Posttraumatic Stress Disorder.
Drugs – November 01, 2024
Source: PubMed
Summary
Psychedelics may significantly enhance memory processes relevant to posttraumatic stress disorder (PTSD). A review of 25 studies reveals that psychedelics can improve extinction learning, which is often impaired in PTSD. Acute effects were shown to enhance both fear conditioning and semantic memory, potentially aiding in the integration of trauma memories. Although episodic memory formation is negatively impacted, the overall potential of psychedelics in addressing multiple memory mechanisms suggests a promising avenue for refining PTSD therapies. Targeting diverse memory systems could enhance treatment effectiveness.
Abstract
Posttraumatic stress disorder (PTSD) is a psychiatric disorder with defining abnormalities in memory, and psychedelics may be promising candidates for the treatment of PTSD given their effects on multiple memory systems. Most PTSD and psychedelic research has investigated memory with fear conditioning and extinction. While fruitful, conditioning and extinction provide a limited model of the complexity of PTSD and phenomenology of psychedelics, thereby limiting the refinement of therapies. In this review, we discuss abnormalities in fear conditioning and extinction in PTSD and review 25 studies testing psychedelics on these forms of memory. Perhaps the most reliable effect is that the acute effects of psychedelics can enhance extinction learning, which is impaired in PTSD. However, the post-acute effects may also enhance extinction learning, and the acute effects can also enhance fear conditioning. We then discuss abnormalities in episodic and semantic memory in PTSD and review current knowledge on how psychedelics impact these memory systems. Although PTSD and psychedelics acutely impair the formation of hippocampal-dependent episodic memories, psychedelics may acutely enhance cortical-dependent learning of semantic memories that could facilitate the integration of trauma memories and disrupt maladaptive beliefs. More research is needed on the acute effects of psychedelics on episodic memory consolidation, retrieval, and reconsolidation and post-acute effects of psychedelics on all phases of episodic memory. We conclude by discussing how targeting multiple memory mechanisms could improve upon the current psychedelic therapy paradigm for PTSD, thereby necessitating a greater emphasis on assessing diverse measures of memory in translational PTSD and psychedelic research.