Transgender hormone therapy (male-to-female) hair becomes more typically female in pattern. Lower leg hair becomes less dense. All of these changes depend to some degree on genetics. Head hair may change slightly in texture, curl, and color. This is especially likely with hair growth from previously bald areas. Eyebrows do not change because they are not androgenic. The lens of the eye changes in curvature. Because of decreased androgen levels, the meibomian glands (the sebaceous glands on the upper and lower eyelids that open up at the edges) produce less oil. Because oil prevents the tear film from evaporating, this change may cause dry
Human head cartoons as having bigger heads as a way of notionally indicating that they have a "larger brain". Additionally, in science fiction, an extraterrestrial having a big head is often symbolic of high intelligence. Despite this depiction, advances in neurobiology have shown that the functional diversity of the brain means that a difference in overall brain size is only slightly to moderately correlated to differences in overall intelligence between two humans. The head is a source for many metaphors and metonymies in human language, including referring to things typically near the human head ( "the head of the bed"), things physically