Olfactory ERPs have not yet been evaluated in CHR patients, namely help-seeking young people with attenuated psychotic symptoms and/or functional decline in the context of genetic risk. For “persons at risk” identified within a sample of 948 young adults who scored in the uppermost deciles on German scales for physical anhedonia and/or perceptual aberration, Becker et al. (1993) reported a reduction in P1/N1 peak-to-peak amplitude at vertex after left nostril stimulation with H2S. However, although this early study provided some evidence for an abnormality in processing of odor stimuli possibly related to risk for psychosis in young adults, several methodological weaknesses considerably limit the value of this report. The present study sought to improve on these shortcomings, including ascertainment of the clinical high-risk status for psychosis, the use of a complete EEG montage, and the application of unbiased, data-driven statistics.
