The effect of the odour of mother's milk and orange on the spectral power of EEG in infants

Abstract

Few studies have been found on the EEG responses to odours in infants. Most of the studies done regarding infants up until now have focused only on the psychological and behavioral reaction of infants to odours. The purpose of the present study is to investigate whether or not relative differences in EEG response are seen before and during the odour presentation of mother's milk and orange in infants, and if they do respond to these odours, are there any differences in the EEG responses? EEG responses to these two odours were studied in 11 healthy mixed fed infants aged from 3.3 to 4.2 months during sleep. Changes in the sleep stage 2 and slow wave sleep EEG's were analyzed by the fast Fourier transformation method. While the mother's milk was presented, a significant decrease in the amplitude of EEG was observed in the delta and theta bands in the bilateral frontal and central regions of the brain, but on orange odour presentation, an increase of delta bands was seen in the central and right parietal regions. Detailed statistical analysis (ANOVA) revealed that the EEG responses to the two odours were significantly different from each other in the delta and theta bands. The present results suggest that these two odours seem to cause a different psychophysiological change in infants.