James W. Prescott - Body Pleasure and the Origins of Violence (1975)
One exceptional study in this respect is that of Brandt F. Steele and C. B. Pollock, psychiatrists at the University of Colorado, who studied child abuse in three generations of families who physically abused their children. They found that parents who abused their children were invariably deprived of physical affection themselves during childhood and that their adult sex life was extremely poor. Steele noted that almost without exception the women who abused their children had never experienced orgasm. The degree of sexual pleasure experienced by the men who abused their children was not ascertained, but their sex life, in general, was unsatisfactory. The hypothesis that physical pleasure actively inhibits physical violence can be appreciated from our own sexual experiences. How many of us feel like assaulting someone after we have just experienced orgasm?