Assesment of odour pleasantness based on identification ability

Olfactory preferences are reflected in our everyday life, whether its eating habits or deodorizing our own body and environment. It is therefore important to understand how they evolve and what factors affect them. It was found that probably the most important factor is the familiarity of the odour, or more precisely, the previous repeated experience with it, and that more known odours are perceived as more pleasant. However, recent research shows that this positive relationship between previous experience (and therefore source knowledge) of the odour and its perceived pleasantness may not apply equally to all odours: odours that are considered to be rather unpleasant appear to be more resilient to the effects of cognitive factors. However, all previous studies have been conducted with adult participants and it is difficult to draw general conclusions.

The aim of the study was to explore the relationship between odour source knowledge verified by the smell identification test and its perceived pleasantness in prepubertal children, whose experience with odours is more limited than the experience of an adult and who are still learning to recognize new smells, as is apparent from the odour identification score growing with age. Participants in the study were identical to the Czech sample from the previous study. The children first evaluated the smell of odours found in the Sniffins Sticks smell test by ticking 1-5 (like at school) and then underwent the identification test itself.

The results showed a somewhat surprisingly positive relationship between the knowledge of the source of odour and its pleasantness for two odors, which ranked among the four worst odours, fish and garlic. Children who correctly identified the stimuli as the smell of fish and garlic have previously also found them more pleasant than the children who did not identify them correctly. This relationship, however, was not found for any of the odours, which were generally judged to be relatively pleasant. The assessment of unpleasant smells, therefore, seems to be influenced more by the children´s knowledge of their source being food and therefore being harmless than the assessment of pleasant smells. Other studies that would use a large number of “edible” and “non-edible” ours of different pleasantness could show whether this finding in children is generally applicable, or whether it is specific to just unpleasant but “edible” smells.