Evidence map›Paper›PMID 32041881›Full record

Trial reportProceedings of the National Academy of Sciences of the United States of America2020

Cannabis increases susceptibility to false memory.

Lilian Kloft, Henry Otgaar, Arjan Blokland, Lauren A Monds, Stefan W Toennes, Elizabeth F Loftus, Johannes G Ramaekers

Open access · hybridAbstract readMulticenter StudyRandomized Controlled Trial
PubMed Full text at PMC Publisher
In one paragraph

Trial report in Proceedings of the National Academy of Sciences of the United States of America, 2020. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 13 papers, 2 of them syntheses that pooled it.

0numbers the graph read from it
0cells of the map it votes in
13citing papers in PubMed, 2 pooled it
3.3field-weighted citation impact, top 7% of its field
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

13 citing papers in PubMed, 2 syntheses or guidelines pooled it, 47 citations in OpenAlex.

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4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

7 authors at 4 institutions in 5 countries.

Lilian KloftFaculty of Psychology and Neuroscience, Maastricht University, 6229 ER Maastricht, The Netherlands; l.kloft@maastrichtuniversity.nl eloftus@uci.edu j.ramaekers@maastrichtuniversity.nl.ORCID 0000-0002-4615-9581
Henry OtgaarFaculty of Psychology and Neuroscience, Maastricht University, 6229 ER Maastricht, The Netherlands.
Arjan BloklandFaculty of Psychology and Neuroscience, Maastricht University, 6229 ER Maastricht, The Netherlands.
Lauren A MondsFaculty of Medicine and Health, The University of Sydney, Sydney, NSW 2006, Australia.
Stefan W ToennesDepartment of Forensic Toxicology, Institute of Legal Medicine, Goethe University of Frankfurt, 60323 Frankfurt, Germany.
Elizabeth F LoftusDepartment of Psychological Science, University of California, Irvine, CA 92697 l.kloft@maastrichtuniversity.nl eloftus@uci.edu j.ramaekers@maastrichtuniversity.nl.
Johannes G RamaekersFaculty of Psychology and Neuroscience, Maastricht University, 6229 ER Maastricht, The Netherlands; l.kloft@maastrichtuniversity.nl eloftus@uci.edu j.ramaekers@maastrichtuniversity.nl.
Maastricht University · NLGoethe University Frankfurt · DEThe University of Sydney · AUUniversity of California, Irvine · US

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

With the growing global acceptance of cannabis and its widespread use by eyewitnesses and suspects in legal cases, understanding the popular drug's ramifications for memory is a pressing need. In a double-blind, randomized, placebo-controlled trial, we examined the acute and delayed effects of Δ9-tetrahydrocannabinol (THC) intoxication on susceptibility to false memory in 64 healthy volunteers. Memory was tested immediately (encoding and retrieval under drug influence) and 1 wk later (retrieval sober). We used three different methods (associative word lists and two misinformation tasks using virtual reality). Across all methods, we found evidence for enhanced false-memory effects in intoxicated participants. Specifically, intoxicated participants showed higher false recognition in the associative word-list task both at immediate and delayed test than controls. This yes bias became increasingly strong with decreasing levels of association between studied and test items. In a misinformation task, intoxicated participants were more susceptible to false-memory creation using a virtual-reality eyewitness scenario and virtual-reality perpetrator scenario. False-memory effects were mostly restricted to the acute-intoxication phase. Cannabis seems to increase false-memory proneness, with decreasing strength of association between an event and a test item, as assessed by different false-memory paradigms. Our findings have implications for how and when the police should interview suspects and eyewitnesses.

Indexed as

Repression, PsychologyCommunicationDronabinolFemaleHumansMaleMemoryYoung AdultDronabinolcannabisDRMfalse memorymisinformationTHC

Identifiers

PMID32041881
PMCPMC7060677
OpenAlexW3004895451

What OpenQuestion holds

Textmetadata
LicenceCC BY-NC-ND
Read underepoch 390

Registered trials

None linked

Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.