Odor mixture alters neural resources during symbolic problem solving

The smell of a cup of coffee is produced by many different odor chemicals combined in a mixture, yet the perception of that odor is of a single unified whole. Recent evidence has demonstrated that mixtures of odors share some of the same spatiotemporal features of speech sounds and may use similar brain resources in associating those features with the symbols they represent. This experiment investigated the hypothesis that an odor mixture would interfere with a math task that requires symbolic but not spatial processing. Results indicated the pattern of brain electrical activity was similar for the single odors and the mixture during spatial processing. During solution of the task requiring symbolic processing, the odor mixture produced a pattern of brain electrical activity different from the single odorants. These data suggest that the perception of odor mixtures may use some of the same resources associated with symbolic processing.