Olfactory decrements as a function of two nights of sleep deprivation

We recently reported that odor identification accuracy declined significantly following 24 h of continuous wakefulness. In the present study, we attempted to extend these findings by testing odor identification accuracy when the duration of wakefulness was more than doubled to over 52 h. The accuracy of odor identification decreased significantly following this period of extended wakefulness, although performance decrements were similar in magnitude to those previously reported following 24 h without sleep. These findings suggest that sleep loss impairs the ability to correctly identify common odors, but this effect does not appear to be exacerbated by additional sleep loss beyond the first 24 h.