False Recognition in Triazolam-Induced Amnesia

Acute administration of the benzodiazepine hypnotic drug triazolam (Halcion) induces temporary amnesia. The present double-blind, placebo-controlled repeated-measures study using the Deese (1959)/Roediger-McDermott (1995) false recognition paradigm examined triazolam’s (0.25 mg/70 kg) interaction with two variables, both designed to decrease false recognition rates under nondrug conditions, but via different mechanisms. As predicted, an interaction between drug condition and number of study presentations (Experiment 1; N = 18) was observed such that participants exhibited decreased false recognition rates for twice- vs. once-presented lists in the placebo condition but increased false recognition rates for twice- vs. once-presented lists in the triazolam condition. In contrast, as predicted, parallel effects of number of studied associates (Experiment 2; N = 18) as a function of drug condition were observed such that participants exhibited decreased false recognition rates for 6- vs. 15-associate lists in both placebo and triazolam conditions. These results suggest that triazolam-treated participants rely primarily on gist-based memory mechanisms and are unable to use item-specific memory mechanisms to suppress false recognition.