Skip to content

Remembering Molly: Immediate and delayed false memory formation after acute MDMA exposure

Lilian Kloft, Henry Otgaar, Arjan Blokland, Stefan W. Toennes, Johannes G. Ramaekers

European Neuropsychopharmacology February 3, 2022 DOI: 10.1016/j.euroneuro.2022.01.005 (opens in new tab)

Study at a glance

AI-extracted from the abstract
Characteristics Double-blind, placebo-controlled trial Peer reviewed
Sample size 60
Population Healthy volunteers with a history of MDMA use
Intervention MDMA
Dose 75 mg
Duration Immediate test and 1-week follow-up
Topics MDMA
Keywords False memory Memory errors Recall Context archaeology Misinformation Cognitive psychology Suggestibility Episodic memory Eyewitness memory Cognition Computer security
Citations 17
Key findings MDMA increased false memory for related but non-critical lures during immediate testing but decreased false memory for critical lures after a one-week delay, and did not consistently affect episodic memory in misinformation tasks.

Abstract

The entactogen 3,4-Methylenedioxymethamphetamine (MDMA) is increasingly being recognized for its therapeutic potential but is also widespread in nightlife settings where it may co-occur with crime. Since previous research detected impaired verbal memory during acute MDMA intoxication, understanding the drug's ramifications in an applied legal context becomes crucial. We conducted a double-blind, placebo-controlled trial to examine acute and delayed effects of MDMA (75 mg) on false memory in 60 healthy volunteers with a history of MDMA use, using three well-established false memory methods: a basic, associative word list (Deese/Roediger-McDermott (DRM)) paradigm and two applied misinformation tasks using a virtual reality crime. Memory was tested immediately (encoding and retrieval under drug influence) and 1 week later (retrieval when sober). Small MDMA-induced impairments of true memory in the word list task were detected at both time points. MDMA increased false memory for related but non-critical lures during the immediate test, and decreased false memory for critical lures after a delay. Episodic memory assessed in the misinformation tasks was not consistently affected. Findings indicate a complex memory profile but no heightened vulnerability to external suggestion in response to MDMA intoxication. Recommendations for future applied legal psychological research include adding measures of recall on top of recognition, using study designs that separate the different memory phases, and potentially testing higher doses. Further research on false memories and suggestibility using imagination procedures can also be relevant for the clinical context.

Comparable studies

Other randomized controlled trials on MDMA, most cited first.

Study Year Design Participants
MDMA-assisted therapy for severe PTSD: a randomized, double-blind, placebo-controlled phase 3 study. Patients with severe PTSD, including those with comorbidities such as dissociation,... 2021 Randomized controlled trial n = 90
The safety and efficacy of {+/-}3,4-methylenedioxymethamphetamine-assisted psychotherapy in subjects with chronic, treatment-resistant posttraumatic stress disorder: the first randomized controlled pilot study. Patients with chronic post-traumatic stress disorder refractory to both psychotherapy... 2010 Randomized controlled trial n = 20
3,4-methylenedioxymethamphetamine (MDMA)-assisted psychotherapy for post-traumatic stress disorder in military veterans, firefighters, and police officers: a randomised, double-blind, dose-response, phase 2 clinical trial. Military veterans and first responders aged 18 or older with chronic PTSD lasting 6... 2018 Randomized, double-blind, dose-response, phase 2 clinical trial n = 26
A randomized, controlled pilot study of MDMA (±3,4-Methylenedioxymethamphetamine)-assisted psychotherapy for treatment of resistant, chronic Post-Traumatic Stress Disorder (PTSD) Patients with treatment-resistant PTSD 2012 Randomized controlled trial n = 12
MDMA-assisted therapy for moderate to severe PTSD: a randomized, placebo-controlled phase 3 trial. Adults with moderate to severe post-traumatic stress disorder 2023 Randomized controlled trial n = 104

Citations in the library

Cited by 8

and 3 more in the library

Cites 23

and 18 more in the library

Explore topics