title: Increased Cortical Thickness in Male-to-Female Transsexualism.
abstract: The degree to which one identifies as male or female has a profound impact on one's life. Yet, there is a limited understanding of what contributes to this important characteristic termedgender identity. In order to reveal factors influencing gender identity, studies have focused on people who report strong feelings of being the opposite sex, such as male-to-female (MTF) transsexuals.
  
  
  
  To investigate potential neuroanatomical variations associated with transsexualism, we compared the regional thickness of the cerebral cortex between 24 MTF transsexuals who had not yet been treated with cross-sex hormones and 24 age-matched control males.
  
  
  
  Results revealed thicker cortices in MTF transsexuals, both within regions of the left hemisphere (i.e., frontal and orbito-frontal cortex, central sulcus, perisylvian regions, paracentral gyrus) and right hemisphere (i.e., pre-/post-central gyrus, parietal cortex, temporal cortex, precuneus, fusiform, lingual, and orbito-frontal gyrus).
  
  
  
  These findings provide further evidence that brain anatomy is associated with gender identity, where measures in MTF transsexuals appear to be shifted away from gender-congruent men.
authors.affiliation: Laboratory of Neuro Imaging, Department of Neurology, UCLA School of Medicine, Los Angeles, CA, USA.
authors.forename: Eileen
authors.initials: E
authors.lastname: Luders
authors.forename: Francisco J
authors.initials: FJ
authors.lastname: Sánchez
authors.forename: Duygu
authors.initials: D
authors.lastname: Tosun
authors.forename: David W
authors.initials: DW
authors.lastname: Shattuck
authors.forename: Christian
authors.initials: C
authors.lastname: Gaser
authors.forename: Eric
authors.initials: E
authors.lastname: Vilain
authors.forename: Arthur W
authors.initials: AW
authors.lastname: Toga
keywords: Brain; Cortex; Gender Dysphoria; Gender Identity Disorder; Gender Incongruence; Gender Nonconformity; MRI; Transgender