title: Handedness, functional cerebral hemispheric lateralization, and cognition in male-to-female transsexuals receiving cross-sex hormone treatment.
abstract: This study examined the impact of sex hormones on functional cerebral hemispheric lateralization and cognition in a group of male-to-female transsexuals receiving cross-sex hormone therapy compared to eugonadal men with a male gender identity. Cerebral lateralization was measured with a handedness questionnaire and a visual-split-field paradigm and cognitive tests sensitive to sex hormone exposure (identical pictures, 3-D mental rotation, building memory) were also administered. Endocrine measures on the day of participation for transsexual and control subjects included total testosterone, free testosterone, estradiol, gonadotropins, and sex hormone binding globulin concentrations. Compared to controls, male-to-female transsexuals had elevated estradiol and sex hormone binding globulin concentrations and suppressed testosterone concentrations. Transsexual subjects showed a trend toward less exclusive right-handedness than controls. No group differences were observed on the visual-split-field or cognitive tasks. No direct associations were observed between endocrine measures and the laterality measures and cognitive performance. Previous observations of female-typical patterns in cerebral lateralization and cognitive performance in male-to-female transsexuals were not found in the current study.
authors.affiliation: Department of Pediatrics, Division of Pediatric Endocrinology, The Johns Hopkins University, Baltimore, Maryland, USA. amy.wisniewski@drake.edu
authors.forename: Amy B
authors.initials: AB
authors.lastname: Wisniewski
authors.forename: Mary T
authors.initials: MT
authors.lastname: Prendeville
authors.forename: Adrian S
authors.initials: AS
authors.lastname: Dobs
mesh_terms: D000328:Adult; D000368:Aged; D016022:Case-Control Studies; D003071:Cognition / Q000187:drug effects*; D004958:Estradiol / Q000097:blood; D004997:Ethinyl Estradiol / Q000097:blood; D007839:Functional Laterality / Q000187:drug effects*; D005783:Gender Identity; D005837:Genitalia, Male / Q000601:surgery; D012739:Gonadal Steroid Hormones / Q000008:administration & dosage* / Q000494:pharmacology*; D006062:Gonadotropins / Q000097:blood; D006801:Humans; D008297:Male; D008875:Middle Aged; D012738:Sex Hormone-Binding Globulin / Q000378:metabolism; D011795:Surveys and Questionnaires; D013739:Testosterone / Q000097:blood; D014189:Transsexualism / Q000188:drug therapy*; D014481:United States
chemical_list: D012739:Gonadal Steroid Hormones; D006062:Gonadotropins; D012738:Sex Hormone-Binding Globulin; D013739:Testosterone; D004997:Ethinyl Estradiol; D004958:Estradiol