Event-related brain potentials and selective attention to acoustic and phonetic cues

N1 and P3 components of the human event-related potential were recorded from subjects performing a syllable discrimination task which required selective attention to one ear at a time. The N1 component was enhanced to all stimuli in the attended ear; while the P3 component was enhanced only to the "target" stimulus in that ear. The results are discussed in terms of hierarchical stages of selective attention.