Cultural history of the buttocks desirability of buttocks: Since the early 2000s, songs about the female buttocks have proliferated, especially in the hip-hop, reggae/dancehall, and R&B genres. Buttocks are often emphasized in pornography. Patricia Hill Collins, an African-American post-modern feminist writer, theorizes that this is derived from a stereotype that black women are promiscuous, and their buttocks are objectified by pornography as a result. A buttocks fetish or buttocks partialism refers to a condition wherein the buttocks becomes a primary focus of sexual attention. It may be associated with coprophilia, panty fetishism, eproctophilia, and sadomasochistic corporal punishment involving the buttocks. "Pygophilia" refers to sexual arousal
Sexual arousal This measurement of blood flow to the male genitals is known as penile plethysmography. This is commonly measured using a strain gauge, a simple mercury strain gauge encompassed in a ring of rubber. The ring surrounds the penis, but does not constrict or cause discomfort. The measure has been found by some to be a reliable and valid measurement of male arousal. More recently, thermography has been developed to measure the physiological measurements of sexual arousal. Studies have found temperature change specific to the genitals during sexual arousal, which supports the validity of this measure. Sexual arousal in women is