Effects of a subanaesthetic concentration of nitrous oxide on memory and subjective experience: Influence of assessment procedures and types of stimuli
Human Psychopharmacology: Clinical and Experimental December 1, 1988 Robert I. Block, M. M. Ghoneim, James V. Hinrichs et al.
Breathing 30% nitrous oxide in oxygen, compared to 100% oxygen, substantially impaired memory in 32 participants (16 men and 16 women). The memory impairments were less severe when tested with forced-choice recognition than with yes/no recognition, and for certain stimuli such as the first names of each participant's close relatives. Other variations in test procedures and stimuli did not affect the impairments. Nitrous oxide also produced numerous subjective effects, including some characteristic of psychedelic drugs, though standard subjective rating scales detected only sedation, not other mood effects.