he describes the functions of the hypothalamus, which plays a key role in, "sex, feeding, drinking, cardiovascular performance, control of body temperature, stress, emotional responses, growth, and many other functions". levay notes that his inah 3 study was his only publication on sex to that date, and that most of his previous research had been on the visual areas of the cerebral cortex. levay compares homosexuality to the disease sickle cell anemia, arguing that it may have persisted through a similar genetic mechanism.