Gender Identity Disorder in Girls

Understanding gender identity disorder first requires an explication of what is meant by gender identity. As a psychological construct, gender identity has been conceptualized with respect to both cognitive and affective parameters. At the cognitive level, gender identity has been defined as the child's ability to accurately discriminate females from males and then to identify her or his own gender status correctly—a task considered by some to be the first “stage” in gender constancy development, of which the “end state” is the knowledge of gender invariance (Fagot, 1995; Kohlberg, 1966; Slaby & Frey, 1975). Most recently, Martin, Ruble, and Szkrybalo (2002) suggested that this rather crude, first-stage developmental acquisition be referred to as the basic self-labeling of gender identity, which most children appear to master some time between the ages of 2 and 3 years. With greater reliance on nonverbal assessment techniques, a number of studies have shown that, prior to this time frame, there is evidence that infants and young toddlers, perhaps as early as 6 months of age, are sensitive to various perceptual features that are reliably correlated with biological sex, such as voice and hairstyle (reviewed in Martin et al., 2002, pp. 917–922). Sensitivity to these and other kinds of perceptual cues (e.g., clothing style) are likely related to the subsequent emergence of basic self-labeling of gender identity.