What does odor fatigue describe?

• A. Increased sensitivity to odor after exposure
• B. Decreased sensitivity to odor after exposure
• C. No change in odor perception after exposure
• D. Temporary blindness to odors

Answer: (B)

Odor fatigue is olfactory adaptation: after being exposed to an odor for a while, the receptors in the nose become less responsive, so the odor is perceived as weaker or may seem to disappear. This temporary drop in sensitivity helps you notice new smells in your surroundings instead of being overwhelmed by a persistent one. Once the odor is gone and the receptors reset, sensitivity returns. The other ideas don’t fit because increasing sensitivity would be the opposite of fatigue, no change means no adaptation occurred, and a temporary loss of smell would be a complete anosmia rather than a reduced perception.