Antarctic wintering--over, suggestion and transient olfactory stimulation: EEG evoked potential and electrodermal responses.

EEG evoked potential and electrodermal responses to real and suggested olfactory stimulation were recorded on a team of nine men who wintered-over at Scott Base, Antarctica. Multi-variate analysis of variance findings indicated some consistent trends despite adverse conditions and marked inter-individual differences. Consistent with studies of secondary afferentation olfaction-related EEGs were evidenced in the occipital area (O1 and O2) as well as the temporal area (T3 and T4). Skin conductance (SC) showed significant responses for real and suggested odorants pre and post wintering-over. Suppression of EEG amplitudes for real and suggested stimuli was evidenced prior to wintering-over. Following wintering-over experience suppression of EEG amplitudes for real stimuli showed a decrease while suppression increased for suggested stimuli. The implications of the suggestion findings are discussed in possible explanation of the apparent conflict between different sources of information about human responses to isolation in the Antarctic environment.