Androgen-concentrating cells in the midbrain of a songbird

Androgen-concentrating cells were found in the midbrain of the chaffinch Fringilla coelebs by autoradiography using tritiated testosterone. Labeled cells were localized primarily in the nucleus intercollicularis, an area from which vocalizations can be electrically stimulated in birds. These autoradiographic results suggest that the nucleus intercollicularis is a site in the action of androgens on avian vocal behavior.