Stability of Evoked Potentials during Auditory Attention

摘要

Click-evoked potentials were recorded from the round window (cochlear microphonic and auditory nerve), cochlear nucleus, and auditory cortex of unanesthetized cats during periods of auditory attention and nonattention. The clicks (irrelevant stimuli) of increasing intensity were presented continuously as background before, during, and after the presentation of a warning stimulus (SI) followed by an imperative (relevant) stimulus (S2) to which the cats made a behavioral response. At all electrode sites, when the cats were attentive to S2, the mean amplitudes of background irrelevant click-evoked potentials within the S1-S2 interval were not significantly different from those of the pretest and posttest control sessions. During auditory attention, no evidence was obtained for peripheral gating at the auditory nerve by the olivocochlear bundle. The dissociation observed between the amplitudes of background irrelevant click-evoked potentials and behavioral performance may reflect overlearning of the S1-S2 response task. Keywords: Olivocochlear bundle. (aw)