Frequency effects of temporary N1 depression following acoustic overload.

The effect of acoustic overload on the N1 potential at different frequences was determined. The conditions of overstimulation were such as to produce temporary effects. The results of the study were: (1) the N1 potential was substantially depressed by acoustic overloads that did not alter the alternating current (AC) cochlear potential; (2) the maximum N1 depression was at one-half octave above the overstimulation frequency; (3) there was no N1 depression at frequencies below the frequency of overstimulation; and (4) the N1 depression recovered within 24 hours.