Effects of hunger and male sex hormone on self-stimulation of the brain.

Abstract

Rats were studied in a lever pressing situation. "Self-stimulation rates with electrodes in medial or lateral parts of the hypothalamus or septal forebrain regions were measured under conditions of high and low hunger drive and high and low androgen levels. Electrodes positively sensitive to androgens tended to be insensitive or inversely sensitive to hunger, and visa versa. This difference appeared to have an anatomical basis, suggesting a localized hunger-reward system within the regions studied differentiated from a localized sexual-reward system.".