Benzodiazepines and memory.

Many anecdotal cases have been reported in the literature of dramatic memory impairment after benzodiazepine intake, raising psychobiological, pharmacological and forensic issues. This paper reviews some methodological difficulties encountered in human studies assessing memory function after benzodiazepine intake and the main results of these studies. Subjects studied are seldom insomniacs and the memory tests generally utilized are far from real-life situations. All benzodiazepines at some doses produce decrement in memory performance (anterograde amnesia) with a retrograde facilitation of retrieval, for the tasks learned before benzodiazepine intake. The mechanism of benzodiazepine induced amnesia is far from clear, but it has been shown that long term memory deficit could be the result of failure of memory consolidation due to rapid sleep onset (less than 5 minutes) after memory test performance during the night awakening (Roth et al. 1984). Many questions remain partially or totally unanswered: Is amnesia a specific effect of benzodiazepines? What are their other effects on cognitive functions? Which attitude to have towards a patient when the physician should prescribe a benzodiazepine?