Effects of medial preoptic lesions on male mouse ultrasonic vocalizations and copulatory behavior

In male mice, lesions in the medial preoptic area (MPA) reduced the proportion of animals showing mounting behavior but failed to abolish ano-genital exploration of the female. The lesions did not effect the amount of 70 kHz ultrasound elicited by intact females or by soiled bedding obtained from female-occupied cages. These results suggest components of male sexual behavior are mediated by neural systems outside the MPA.