ABSTRACT
In recent years, burgeoning evidence indicates sex and gender differences in pain in both clinical and experimental settings. In order to discuss these findings, it is helpful to understand the distinction between “sex” and “gender.” Specifically, sex refers to biological substrates that clearly distinguish an organism as “male” or “female” in terms of their genetic composition including chromosomes (XX for females and XY for males), hormones, anatomy, and the subsequent development of secondary physical characteristics, which place the organisms in the category “female” or “male” (Frable, 1997; Hughes, 2003; Pollad & Hyatt, 1999; Wizemann & Pardue, 2001). Gender refers to the way in which an individual is defined based on socioculturally shaped behaviors and traits (such as femininity and masculinity) that are an amalgam of the psychological, social, and cultural factors that influence it (Pollard & Hyatt, 1999; Robinson et al., 2000; Wizemann & Pardue, 2001). Other theorists define gender as “the structured set of gendered personal identities that results when the individual takes the social construction of gender and the biological ‘facts’ of sex and incorporates them into an overall self-concept.” (Ashmore, 1990; Pollard & Hyatt, 1999; Robinson et al., 2000; Wizemann & Pardue, 2001). It is important to recognize that gender roles are sculpted by both biological and social factors. Indeed, the relevance of social learning and its effect on sex differences in pain modulation have been presented from a neurobiological perspective (Choleris & Kavaliers, 1999).
