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Benzodiazepines and semantic memory: effects of lorazepam on the Moses illusion
Marie Izaute1, Laurence Paire-Ficout, Elisabeth Bacon
1Laboratoire de Psychologie Sociale de la Cognition (LAPSCO-UMR 6024 CNRS), Universite Blaise Pascal, 34 Avenue Carnot, 63037 Clermont-Ferrand Cedex, France. Marie.Izaute@srvpsy.univ-bpclermont.fr
Rationale:
When asked "How many animals of each kind did Moses take on the ark?", people fail to notice the distortion introduced by the impostor "Moses" and respond "two". It has been argued that the effect must be due to the existence of a partial-match process. In most situations, the form of a question is not likely to closely match the memory representation it queries. Thus, for the partial match hypothesis people ignore some semantic distortions. In the same vein, it has been shown that the benzodiazepine lorazepam drug induces some impairments of semantic memory as participants under lorazepam provide more incorrect recalls than placebo do with general information questions.
Objectives:
The aim of this study was to investigate the effects of the benzodiazepine lorazepam on the Moses illusion paradigm.
Method:
The effects of lorazepam (0.038 mg/kg) and of a placebo were investigated in 28 healthy volunteers. Twenty-two illusory questions were presented along with 72 normal general information questions.
Results:
Lorazepam impaired the ability to detect the Moses illusion. Moreover, lorazepam participants appeared less biased to consider a question distorted than placebo participants.
Conclusions:
The temporary and reversible semantic memory impairments experienced by participants when falling into the Moses illusion are more frequent under lorazepam. The amnesic drug lorazepam may impair semantic processing as well as the strategic control of memory.
Insights
Lorazepam, a benzodiazepine drug, impairs semantic memory, making people more susceptible to the Moses illusion. This suggests lorazepam affects semantic processing and memory control.
Area of Science:
- Cognitive Psychology
- Neuropharmacology
Background:
- The Moses illusion highlights semantic memory's partial-match process, where individuals overlook distortions.
- Benzodiazepines, like lorazepam, are known to impair cognitive functions, including semantic memory.
Purpose of the Study:
- To investigate the impact of lorazepam on the Moses illusion.
- To assess how lorazepam affects semantic memory processing in the context of illusory questions.
Main Methods:
- A double-blind, placebo-controlled study with 28 healthy volunteers.
- Administration of lorazepam (0.038 mg/kg) or placebo.
- Presentation of 22 Moses illusion questions and 72 general information questions.
Main Results:
- Lorazepam significantly impaired participants' ability to detect the Moses illusion.
- Participants receiving lorazepam showed a reduced bias to identify distorted questions compared to the placebo group.
Conclusions:
- Lorazepam increases susceptibility to the Moses illusion, indicating impaired semantic memory.
- The findings suggest lorazepam negatively impacts semantic processing and strategic memory control.
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