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Jason Samaha

Department of Psychology, University of California, Santa Cruz.

2 papers in the library · 30 citations · publishing 2022-2024

Papers

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 1, 2024 Manoj K Doss, Jason Samaha, Frederick S Barrett et al. 24 citations

Psychoactive drugs produce unique subjective states, but their effects on episodic memory often overlap. This reanalysis of 10 data sets (28 drug conditions) used signal detection models to separate three memory processes: recollection (retrieving specific details), familiarity (recognizing without details), and metamemory (introspecting about memory accuracy). Sedatives impaired both recollection and familiarity during encoding but enhanced recollection during consolidation. Dissociatives and cannabinoids impaired recollection during encoding, and cannabinoids increased false recollections during retrieval. Psychedelics impaired recollection during encoding but tended to enhance familiarity. Stimulants enhanced metamemory during encoding and retrieval but impaired metamemory during consolidation. These distinct patterns help explain drug-specific phenomena like sedative-induced blackouts and psychedelic presque vu, and suggest that memory quantity and stability influence metamemory.

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

bioRxiv (Cold Spring Harbor Laboratory) May 24, 2022 Manoj K. Doss, Jason Samaha, Frederick S. Barrett et al. 6 citations preprint

Different classes of psychoactive drugs—sedatives, dissociatives, psychedelics, stimulants, and cannabinoids—each produce unique patterns of effects on the conscious processes underlying episodic memory, depending on whether they act during encoding, consolidation, or retrieval. Reanalyzing confidence data from 10 published datasets (28 drug conditions) with signal detection models, the authors found that all drugs except stimulants impaired recollection when given at encoding; sedatives, dissociatives, and cannabinoids also impaired familiarity at encoding. Psychedelics at encoding enhanced familiarity and did not affect metamemory, while dissociatives and cannabinoids tended to enhance metamemory. Stimulants enhanced metamemory at encoding and retrieval but impaired it at consolidation. These distinct profiles may help explain drug-specific subjective phenomena such as sedative-induced blackouts or psychedelic déjà vu.