Gender differences in behaviour: activating effects of cross-sex hormones.
The relative contribution of organizing and activating effects of sex hormones to the establishment of gender differences in behaviour is still unclear. In a group of 35 female-to-male transsexuals and a group of 15 male-to-female transsexuals a large battery of tests on aggression, sexual motivation and cognitive functioning was administered twice: shortly before and three months after the start of cross-sex hormone treatment. The administration of androgens to females was clearly associated with an increase in aggression proneness, sexual arousability and spatial ability performance. In contrast, it had a deteriorating effect on verbal fluency tasks. The effects of cross-sex hormones were just as pronounced in the male-to-female group upon androgen deprivation: anger and aggression proneness, sexual arousability and spatial ability decreased, whereas verbal fluency improved. This study offers evidence that cross-sex hormones directly and quickly affect gender specific behaviours. If sex-specific organising effects of sex hormones do exist in the human, they do not prevent these effects of androgen administration to females and androgen deprivation of males to become manifest.
Department of Child and Adolescent Psychiatry, University of Utrecht, The Netherlands.
S H
SH
Van Goozen
P T
PT
Cohen-Kettenis
L J
LJ
Gooren
N H
NH
Frijda
N E
NE
Van de Poll
D000328:Adult; D000374:Aggression / Q000187:drug effects / Q000502:physiology; D000704:Analysis of Variance; D000726:Androgen Antagonists / Q000494:pharmacology*; D000728:Androgens / Q000494:pharmacology*; D000786:Anger / Q000187:drug effects / Q000502:physiology; D001519:Behavior / Q000187:drug effects* / Q000502:physiology; D003071:Cognition / Q000187:drug effects / Q000502:physiology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012727:Sex Characteristics; D012725:Sexual Behavior / Q000187:drug effects / Q000502:physiology; D011795:Surveys and Questionnaires; D014189:Transsexualism
D000726:Androgen Antagonists; D000728:Androgens