INVITED ESSAY Sexual Differentiation of Childhood Play: A Contemporary Psychoanalytic Perspective

Abstract Freud (1905/1953) anchored his theories ofuncon-scious psychological functioning in observations and infer-ences aboutchildhoodsexuality.These ideas remain influential among psychoanalysts today. Much progress subsequently occurred in extra-psychoanalytic research in human sexuality. This included the discovery in 1959 of an entirely new area of psychology: the sexual differentiation of behavior (Phoenix, Goy, Gerall, & Young, 1959; Wallen, 2009). The observations that led to this new field originally concerned the effects of androgen administered prenatally to non-human animals. This early research was compatible with later studies of humans as well. Prenatal androgen influences both erotic and non-erotic behavior, including childhood rough-and-tumble play (RTP). We have previously emphasized the need to integrate this psy-choneuroendocrineknowledge with psychoanalytic theory and practice (Friedman, 1988; Friedman & Downey, 2002, 2008a, 2008b). In this article, we discuss additional aspects of the rela-tionshipbetweensexuallydifferentiatedchildhoodplay,particu-larly RTP, and gender differences in psychosexual development and functioning. These topics and other aspects of the sexual differentiation of behavior have been under-emphasized in psychoanalytic thought