Odor identification ability predicts executive function deficits following sleep deprivation

Area of Science:

• Neuroscience
• Sleep Science
• Cognitive Psychology

Background:

• Odor identification is linked to prefrontal lobe function.
• Prolonged wakefulness may impair olfactory abilities.
• Sleep loss impacts cognitive functions, particularly executive functions.

Purpose of the Study:

• To investigate if reduced odor identification during sleep loss predicts executive function deficits after further sleep deprivation.
• To determine if smell identification tests can serve as an indicator of vulnerability to sleep deprivation.

Main Methods:

• 54 healthy adults underwent 45 hours of continuous wakefulness.
• The University of Pennsylvania Smell Identification Test (SIT) was administered twice during 24 hours of sleep deprivation.
• Performance on the Wisconsin Card Sorting Test (WCST) was assessed after 45 hours of wakefulness.

Main Results:

• Decreases in SIT performance during sleep deprivation predicted poorer WCST performance.
• Individual differences in olfactory decline correlated with executive function impairments.

Conclusions:

• Reduced odor identification ability during sleep loss is a predictor of executive function deficits following extended wakefulness.
• Smell identification tests may offer a simple method to assess susceptibility to the cognitive effects of sleep deprivation.