demonstrations:olfactory_adaptation

Olfactory Adaptation

Materials: ★☆☆ Easy to get from supermarket or hardware store
Difficulty: ★☆☆ Can be easily done by most teenagers
Safety: ★☆☆ Minimal safety procedures required

Categories: Senses and Perception

Alternative titles: Smell Adaptation

Summary

Olfactory adaptation is the process where the sense of smell becomes less sensitive to a persistent odor over time. This demonstration shows how quickly the nose adjusts when exposed to a continuous smell and how sensitivity returns when a new odor is introduced.

Procedure

  1. Choose a safe and distinct-smelling item (such as an orange peel, vanilla extract, or vinegar).
  2. Have participants smell the item for about 30–60 seconds, continuing to breathe normally.
  3. Ask them to describe how strong the smell seems at the beginning and after a short time.
  4. After adaptation occurs and the smell seems weaker or disappears, introduce a new odor (such as peppermint oil, coffee grounds, or cinnamon).
  5. Ask participants to note how quickly they can detect the new scent compared to the adapted one.

Brain Waves - Smell (olfactory adaptation) activity - Parachute:


Sense of Smell Teaching Demo Plus Fun Activity - Teacher Cathy:


Variations

  • Compare how long adaptation takes with different scents.
  • Test whether stronger odors cause slower or faster adaptation.
  • Alternate between strong and mild scents to see if adaptation differs.
  • Try closing one nostril to see if adaptation occurs differently in each nostril.

Safety Precautions

  • Only use safe, non-toxic household items or food-based scents.
  • Avoid strong chemicals or allergens that could irritate the nose or cause allergic reactions.
  • Do not place liquids directly in or too close to the nose; use soaked cotton balls or small open containers.

Questions to Consider

  • Why does the smell seem to disappear after a while? (The olfactory receptors become less responsive to continuous stimulation, and the brain filters out constant signals.)
  • Why can we smell a new odor so easily after adaptation? (The brain is primed to notice changes in the environment, especially new stimuli.)
  • How might olfactory adaptation be useful in daily life? (It prevents the nervous system from being overwhelmed and allows focus on new, potentially important smells.)
  • Why do some people describe this as being “nose blind”? (It is a common term for temporary loss of sensitivity to a familiar or constant odor.)