Unique effects of sedatives, dissociatives, psychedelics, stimulants, and cannabinoids on episodic memory: A review and reanalysis of acute drug effects on recollection, familiarity, and metamemory.
Psychological review – March 01, 2024
Source: PubMed
Summary
Psychoactive drugs have surprisingly distinct effects on how we remember. A reanalysis of 28 drug conditions revealed how sedatives, dissociatives, psychedelics, stimulants, and cannabinoids uniquely impact our ability to recall specific details (recollection), recognize generally (familiarity), and judge memory accuracy (metamemory) during memory formation, stabilization, and access. Sedatives *enhanced* recollection during stabilization. Stimulants *boosted* metamemory and familiarity. Psychedelics *improved* familiarity. These patterns illuminate drug-specific memory phenomena, showing how memory quantity and stability influence our confidence in what we recall.
Abstract
Despite distinct classes of psychoactive drugs producing putatively unique states of consciousness, there is surprising overlap in terms of their effects on episodic memory and cognition more generally. Episodic memory is supported by multiple subprocesses that have been mostly overlooked in psychopharmacology and could differentiate drug classes. Here, we reanalyzed episodic memory confidence ratings from 10 previously published data sets (28 drug conditions total) using signal detection models to estimate two conscious states involved in episodic memory and one consciously controlled metacognitive process of memory: autonoetic retrieval of specific details (recollection), noetic recognition absent of retrieved details (familiarity), and retrospective introspection of memory decisions (metamemory). Sedatives, dissociatives, psychedelics, stimulants, and cannabinoids had unique patterns of effects on these mnemonic processes dependent on whether they impacted encoding, consolidation, or retrieval (the formation, stabilization, and access to memory traces, respectively). Sedatives at encoding reliably impaired both recollection and familiarity but at consolidation enhanced recollection. Dissociatives and cannabinoids at encoding impaired recollection but less reliably impaired familiarity, and cannabinoids at retrieval increased false recollections. These drug-induced encoding impairments occasionally came with metamemory enhancements, perhaps because of less interstimulus interference. Psychedelics at encoding impaired recollection but tended to enhance familiarity and did not impact metamemory. Stimulants at encoding enhanced metamemory, at consolidation impaired metamemory, and at retrieval enhanced familiarity and metamemory. These findings allude to mechanisms underlying the idiosyncratic phenomena of drugs, such as blackouts from sedatives and presque vu from psychedelics. Finally, these findings converge on a model in which memory quantity and stability influence metamemory. (PsycInfo Database Record (c) 2024 APA, all rights reserved).