Related Experiment Video
Updated: May 13, 2026

Testing for Odor Discrimination and Habituation in Mice
Published on: May 5, 2015
Habituation effects of pleasant and unpleasant odors
1Department of Occupational and Environmental Medicine, Goteborg University, Medicinaregatan 16, Box 414, 405 30 Göteborg, Sweden. Ilona.croy@amm.gu.se
Objective:
The hedonic value of odors is reflected in chemosensory evoked potentials with more salient unpleasant odors being processed differently from pleasant odors. However, it is not known if this effect is stable over time. It was examined if chemosensory evoked potentials towards pleasant and unpleasant odors change with repeated presentation.
Methods:
42 participants received two pleasant (Peach and PEA) and one unpleasant (H2S) intensity matched odors in a block design. Intensity and pleasantness were rated after each presentation. Subjective ratings, as well as N1 and P2 of the first stimulus of each block were compared with the two following stimuli of each block.
Results:
Early and late components of the chemosensory evoked potentials had shorter latencies in response to the unpleasant H2S compared to PEA and Peach. Pleasantness ratings for H2S increased with repeated presentation but were far below neutral even for the third stimulus in a row. In line with this, for H2S only, the P2 amplitude diminished with repeated presentation.
Conclusion:
We assume that unpleasant stimuli catch more attention first hand. However, repeated presentation leads to reduced emotional salience of unpleasant stimuli only, which is mirrored in a decrease of neuronal activation.
More Related Videos
06:27An Olfactory Preference Test for Measuring Olfactory Hedonic Biases in Mouse Models of Depression
Published on: July 11, 2025
06:13Combining a Breath-Synchronized Olfactometer with Brain Simulation to Study the Impact of Odors on Corticospinal Excitability and Effective Connectivity
Published on: January 19, 2024
Related Concept Videos
Classical Conditioning in Daily Life
John B. Watson and Rosalie Rayner famously demonstrated the development of fear through classical conditioning in their experiment with Little Albert. They paired the...
Conditioned Taste Aversion
A notable characteristic of conditioned taste aversion is that it often requires only a single exposure...
Physiology of Smell and Olfactory Pathway
The olfactory...
Analgesia and Pain Management
Factors Affecting Perception
An illustrative example of a perceptual set is the scenario where an airline pilot told...
Olfactory Receptors: Location and Structure