The choice of click polarity for neurodiagnostic application of the brainstem auditory evoked potentials(BAEF) has long been an topic of debate. The latencies and amplitudes of the evoked potentials are affected by the type, frequently, intensity and click polarity of stimulus sound. The purpose of this study was to demonstrate the effects of click polarities of stimuli and those of sex on brainstem auditory evoked potentials.

The subjects of this study were 40 normal volunteers between 21 to 30 years of age(20 male, 20 Female). Tests were done at 70dBnHL on both sides with rarefaction, condensation, alternative click polarities.

The results were as follows;

1) Minor sex differences were seen in the absolute wave Ⅴ latency and Ⅰ-Ⅲ, and Ⅰ -Ⅴ interwave latencies on all click polarities, and in the absolute wave Ⅴ amplitude on alternative click polarity.

2) There were no significant differences of absolute wave latencies, interwave latencies, and amplitudes in intersidal comparison.

3) The mean latencies of wave Ⅰ, Ⅲ, Ⅴ were shortest and amplitude of wave I was highest on rarefaction click polarity. The mean interpeak latency of wave Ⅰ-Ⅲ was shortest on condensation click polarity.

4) Condensation and alternative click stimulations tended to fuse wave Ⅳ and Ⅴ into a single broad peak, whereas rerefaction stimulations most often produced two distinct peaks.