Gustofacial and olfactofacial responses in human adults
Romy Weiland1, Heiner Ellgring, Michael Macht
1Department of Psychology, University of Mainz, Germany. weilanr@uni-mainz.de
Chemical Senses
|September 30, 2010
Summary
Adult facial reactions to tastes and odors largely mirror those of newborns, with some differences suggesting socialization influences. Adults displayed unique smiles to unpleasant tastes, possibly for communication.
Area of Science:
- Sensory science
- Psychology
- Human behavior
Background:
- Facial expressions in newborns show distinct reactions to tastes and odors.
- Adults possess greater voluntary control over facial muscles compared to newborns.
Purpose of the Study:
- To investigate if facial reactions to tastes and odors observed in newborns persist in adults.
- To explore the influence of voluntary facial control and socialization on adult emotional expressions.
Main Methods:
- Twenty-eight healthy adults (14 female) were presented with various concentrations of five basic tastes (bitter, salty, sour, sweet, umami) and six distinct odors.
- Facial reactions were video-recorded and analyzed using the Facial Action Coding System (FACS).
Main Results:
- Adult facial reactions differentiated between stimuli of opposing valences, with negative displays for unpleasant tastes/odors and positive displays for sweet taste.
- Unlike newborns, adults exhibited smiles at higher concentrations of some unpleasant tastes and negative displays with increased sweetness.
- Most adult facial reactions to tastes and odors aligned with newborn responses, except for a "social" smile towards unpleasant tastes.
Conclusions:
- Basic facial displays to tastes and odors remain stable from infancy to adulthood.
- Adult facial reactions may incorporate additional expressions influenced by socialization and communicative functions.
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