Analysis of gender differences in the auditory brainstem response.

This study examined the effects of hormones, head size, and oral temperatures on latencies and amplitudes of the auditory brainstem response in 10 young women, 10 young men, and 5 postmenopausal women. Significant gender differences between men's and women's auditory brainstem responses were confirmed. Men showed longer latencies and smaller amplitudes than women. Results showed that oral temperature has little effect on auditory brainstem response latencies and amplitudes. Head size affects waves III, V, and the amplitude of wave V, but is not entirely responsible for the gender latency difference. By examining young women with normal monthly hormonal cycles, significant changes in the absolute latencies of wave V were observed. These changes were correlated with hormonal changes as measured from venous blood samples. It was concluded that the etiology of the gender difference is a combination of hormonal and head-size differences.