For most people, heterosexual impulses predominate, although all are bisexual to some degree. (Viorst, Judith. Necessary Losses. p 107-109. NY:Simon & Schuster, 1986.)
There are exclusive homosexuals and optional (bisexual) homosexuals. Compares exclusive homosexuality in males with Androgen-Insensitivity Syndrome (AIS) and MF transsexuality. (Seligman, Martin E P., PhD. What You Can Change…and What You Can’t. p 148-173. NY:Fawcett Books, 1993.)
Defines hermaphrodites as true bisexuals: one active ovary and one active testis. They could impregnate themselves, but are usually raised as either girls or as boys. (Durden-Smith, Jo, and Diane deSimone. Sex and the Brain. p 90-186. NY:Arbor House Publishing, 1983.)
Bisexual men are often married and engage in casual sex with other males for variety. Bisexual women seek long-term relationships with members of either gender and are more likely to alternate partners. (Wilson, Glenn. The Great Sex Divide. p 86-87. England: Peter Owen Publishers, 1989.)
A sexual high is generated primarily by the hypothalamus. (Newberg, Andrew, MD, et al. Why God Won’t Go Away. p 125-126. NY: Ballantine Books, 2001.)
Refer to Sexual Orientation and the Brain for additional information.