The Physiological Society of Japan|Springer Japan KK
Abstract
This study aimed to investigate how odor stimulation affects taste perception. Electroencephalogram (EEG) signals were measured from the frontal region of the head in normal subjects, and frequency analyses were performed. Each odor stimulation was delivered while the subject tasted chocolate, using chocolate paste as the odorant for ‘matched odor stimulation’, and garlic paste for ‘unmatched odor stimulation’. Differences appeared in EEG signals. Comparing frequencies of EEGs under ‘unmatched odor stimulation’ with those under ‘matched odor stimulation’ showed that the occupancy rate of the theta-frequency band under ‘unmatched odor stimulation’ was higher than that under ‘matched odor stimulation’. Interestingly, a negative correlation existed between the occupancy rate of the theta-frequency band and the subjective feeling of chocolate sweetness. The present findings suggest that when we receive unmatched smell against the foods, subjective feelings are disturbed, and theta-band brain activity is increased while cross-checking the unmatched information
