[Solved] Discuss Bem's exotic becomes erotic (EBE) theory of the development of sexual orientation. Brain Injury: Physical trauma to the brain, which can lead to varying degrees of impairment in cognitive functions, physical abilities, or emotional behaviors. Testosterone: A steroid hormone associated with sperm production, the development of secondary sex characteristics in males, and the sex drive in both males and females. Pubic Hair: Hair that grows in the genital area during puberty as a secondary sexual characteristic. Precocious Puberty: A condition in which puberty begins at an unusually early age, often before age 8 in girls and age 9 in boys.