Effect of methohexitone, diazepam and sodium 4-hydroxybutyrate on short-term memory.

Short-term memory following the intravenous injection of methohexitone (0.15 mg/kg), diazepam (0.05 mg/kg) and sodium 4-hydroxybutyrate (10 mg/kg) has been examined by means of a visually presented digit retention test with intervals of 4 and 20 seconds before recall. No significant change was found with the 4-second interval; statistically significant impairment was found with the 20-second intervaL It is postulated that the effect of these drugs is to accelerate decay of the memory trace, thus impairing its consolidation and producing anterograde amnesia. A versatile computerized test of short-term memory is described.