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Genderinkongruenz, das Gehirn und die Hormone

  • Michael van Trotsenburg
Originalien
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Zusammenfassung

Personen mit Genderinkongruenz (GI) und „gendernonkonformes“ Verhalten sind in der Öffentlichkeit und in den Medien zunehmend sichtbar. Aktuelle Studien zeigen, dass etwa 0,8 % der Bevölkerung sich selbst als Transgender definiert. Gleichzeitig geben diese Personen an, dass sie unter Genderdysphorie leiden und ernsthaft eine Geschlechtsanpassung in Betracht ziehen.

Über die Gründe für diese explosionsartige Zunahme der Prävalenz wird spekuliert. Einerseits werden gesellschaftliche Faktoren vermutet, wie die zunehmende Akzeptanz von deviantem Verhalten oder die Aufmerksamkeit, die gendernonkonformem Verhalten in den Medien entgegengebracht wird. Andererseits werden die heutigen medizinischen Möglichkeiten für eine erfolgreiche somatische Geschlechtsangleichung genannt.

Unser Verständnis vom Entwicklungsprozess des Gehirns im Allgemeinen und der Genderidentität im Besonderen ist in den letzten Jahrzehnten massiv gewachsen. Sexsteroide beeinflussen die Entwicklung des Gehirns und unser geschlechtsspezifisches Verhalten. Das Konzept von „organisierenden“ und „aktivierenden“ Effekten der Sexsteroide hat sich etabliert und scheint auch für das puberale Gehirn von einer gewissen Bedeutung.

Die Ätiologie einer atypischen zerebralen Entwicklung und der Manifestation einer Genderinkongruenz sind weit weniger klar. Viele Studien zeigen inkonsistente und widersprüchliche Daten. Eine eindeutige Assoziation einer genetischen, neuroanatomischen oder endokrinologischen Abweichung mit Genderinkongruenz oder Genderdysphorie wurde bis heute nicht gefunden. Es wird die aktuelle Literatur mit Schwerpunkt Neuroimaging Studies bei Transgenderpersonen beleuchtet.

Schlüsselwörter

Genderinkongruenz Genderdysphorie Genderidentität Transsexualität Geschlechtsspezifische Gehirnentwicklung 

Gender incongruence, brain and hormones

Abstract

People with gender incongruence (GI) and gender nonconforming identities are increasingly visible in the public and in the media. As an umbrella term for various gender-nonconforming roles and identities persons with any form and expression of gender incongruence are called transgender persons. Recent data reveal that up to 0.8% of the population consider themselves as gender incongruent and suffer from gender dysphoria. Most of these persons state that they seriously entertain the idea of gender reassignment.

Reasons for the growing numbers of gender incongruent persons across all ages are far from clear. Both societal factors as openness towards nonconforming attitudes and media attention as well as the medical progress enabling successful physical sex reassignment may account for the increasing numbers.

Our understanding of the process of typical gender development has increased considerably over the past decades. Sex hormones affect brain and behaviour and play an important role in many differences between men and women. The influence of sex steroids on the structural development of the brain is denoted organisational, whereas the effects of hormones on preexisting structures are classified as activational. However, when it comes to gender and nonconforming identities much remains unravelled. GI has been linked to genetic and hormonal factors, but much of the information comes from single studies or is inconsistent across studies. To date not a single study provides clear evidence for unequivocal linkage of severe gender dysphoria and hormonal disorders or genetic deviations. However, some very captivating studies point to somatic causality. Briefly the current evidence on the etiology of gender incongruence from genetic, neuroanatomical and neuroimaging studies are highlighted.

Keywords

Gender incongruence Gender dysphoria Gender identity Transsexuality Sex-specific brain development 

Notes

Einhaltung ethischer Richtlinien

Interessenkonflikt

M. van Trotsenburg gibt an, dass kein Interessenkonflikt besteht.

Dieser Beitrag beinhaltet keine von den Autoren durchgeführten Studien an Menschen oder Tieren.

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Copyright information

© Springer-Verlag GmbH Austria, ein Teil von Springer Nature 2017

Authors and Affiliations

  1. 1.Dep. Obs. & Gyn.VU University medical centerAmsterdamNiederlande

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