Stem‐completion tasks (indirect, direct inclusion and exclusion) are differently affected by equipotent doses of lorazepam and flunitrazepam

Abstract

This study was designed to explore the effects on performance in stem-completion tasks of two benzodiazepines (BZ) in equipotent doses: lorazepam, a drug that atypically disrupts perceptual priming, and flunitrazepam, a compound with standard BZ effects. The study followed a placebo-controlled, double-blind, parallel-group design. Thirty-six young and healthy subjects carried out three completion tasks at theoretical peak-plasma concentrations of drugs: (a) indirect tasks, in which the subjects were instructed to complete stems with the first word that came to mind; (b) direct inclusion tasks/cued recall, in which the participants had to try to use words seen at study as completions; and (c) direct exclusion tasks, in which words seen at study were to be avoided. The PDP was applied to the results in the inclusion and exclusion tasks, to obtain indices of explicit/controlled (C) and implicit/automatic (A) memory. The C index was lowered by both BZs and A was equivalent in all treatments, confirming the general amnestic action of BZs. However, lorazepam led to decreases in completions in the indirect and inclusion tasks, while flunitrazepam impaired performance in the exclusion task. The qualitative differences between the drugs in their effects on performance suggest that these BZs may lead to differences in response bias.

Effects of a benzodiazepine on free recall of semantically related words

“…Results in the control tasks (CT, DSST, VAS and Prose Recall) revealed lower performance of Flu1.0 and Flu1.3 in comparison to placebo, indicating that the doses used in the present study were high enough to corroborate previous findings of cognitive effects of BDZ (psychomotor, attentional, subjective and amnesic) (Buffett-Jerrott and Stewart, 2002;Curran, 2000;Pompéia et al, 2000Pompéia et al, , 2003. Memory impairment was evident in free recall of words and prose even though normal forgetting rate was observed in recall of prose after flunitrazepam ingestion.…”

Zolpidem and memory: a study using the process-dissociation procedure

“…The use of a more refined paradigm to investigate memory impairment, the PDP (Jacoby 1991), also showed that 10 mg zolpidem affects C, confirming that this drug impairs episodic memory as observed through the application of this same paradigm to data from BZ-treated subjects (Vidailhet et al 1996;PompØia et al 2003a).…”

Avaliação da memória sob anestesia venosa total

“…The medications used for anesthesia have different effects on memory 18,[20][21][22] . In our study, patients were not premedicated, so that the results would not be affected.…”