Transgender Research in the 21st Century: A Selective Critical Review From a Neurocognitive Perspective.

Gender dysphoria describes the psychological distress caused by identifying with the sex opposite to the one assigned at birth. In recent years, much progress has been made in characterizing the needs of transgender persons wishing to transition to their preferred gender, thus helping to optimize care. This critical review of the literature examines their common mental health issues, several individual risk factors for psychiatric comorbidity, and current research on the underlying neurobiology. Prevalence rates of persons identifying as transgender and seeking help with transition have been rising steeply since 2000 across Western countries; the current U.S. estimate is 0.6%. Anxiety and depression are frequently observed both before and after transition, although there is some decrease afterward. Recent research has identified autistic traits in some transgender persons. Forty percent of transgender persons endorse suicidality, and the rate of self-injurious behavior and suicide are markedly higher than in the general population. Individual factors contributing to mental health in transgender persons include community attitudes, societal acceptance, and posttransition physical attractiveness. Neurobiologically, whereas structural MRI data are thus far inconsistent, functional MRI evidence in trans persons suggests changes in some brain areas concerned with olfaction and voice perception consistent with sexual identification, but here too, a definitive picture has yet to emerge. Mental health clinicians, together with other health specialists, have an increasing role in the assessment and treatment of gender dysphoria in transgender individuals.

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