CAH-Mädchen und die Auswirkung pränataler Hormone auf das Verhalten

Mädchen mit Congenital Adrenal Hyperplasia haben aufgrund einer Überfunktion der Nebennierenrinde wesentlich mehr Testosteron als Mädchen, die davon nicht betroffen sind. Die Überfunktion wird nach der Geburt reguliert, so dass der Überschuss nur vor der Geburt, pränatal , vorliegt.

Ich schrieb dazu schon einmal:

Bei Congenital adrenal hyperplasia (CAH) ist die Hormonsynthese in den Nebennierenrinde gestört, die deswegen statt  Cortisol und Aldosteron vermehrt deren Vorstufen Pregnenolon und  Progesteron ausgeschüttet. Da die geringeren Mengen der eigentlich zu bildenden Stoffe in den passenden Gehirnregionen, zB dem Hypothalamus und die Hypophyse registriert wird, wird doch allgemein die Produktion der Nebennierenrinde hochgefahren, die dann auch vermehrt das Sexualhormon Testosteron ausschüttet. Dieser Effekt tritt bereits im Mutterleib ein und führt daher dazu, dass der Fötus einer erhöhten Testosteronkonzentration ausgesetzt ist. Dies sollte nach der Theorie der hormonellen Prägung der Geschlechter im Mutterleib dazu führen, dass die Mädchen sich insgesamt männlicher verhalten und eher bisexuell oder homosexuell sind.

Gerade da die Kinder nach der Geburt kein zusätzliches Testosteron mehr produzieren sind sie ansonsten unauffällige Mädchen, die demnach nach den sozialen Theorien die weiblichen Geschlechterrollen übernehmen sollten. Tatsächlich verhalten sie sich aber sehr männlich.

Ich habe mal ein paar Studien zusammen gesucht:

1. Melissa Hines et all, 2010:

Androgen and psychosexual development: Core gender identity, sexual orientation, and recalled childhood gender role behavior in women and men with congenital adrenal hyperplasia (CAH)

We assessed core gender identity, sexual orientation, and recalled childhood gender role behavior in 16 women and 9 men with congenital adrenal hyperplasia (CAH) and in 15 unaffected female and 10 unaffected male relatives, all between the ages of 18 and 44 years. Women with CAH recalled significantly more male-typical play behavior as children than did unaffected women, whereas men with and without CAH did not differ. Women with CAH also reported significantly less satisfaction with the female sex of assignment and less heterosexual interest than did unaffected women. Again, men with CAH did not differ significantly from unaffected men in these respects. Our results for women with CAH are consistent with numerous prior reports indicating that girls with CAH show increased male-typical play behavior. They also support the hypotheses that these women show reduced heterosexual interest and reduced satisfaction with the female sex of assignment. Our results for males are consistent with most prior reports that boys with CAH do not show a general alteration in childhood play behavior. In addition, they provide initial evidence that core gender identity and sexual orientation are unaffected in men with CAH.
Finally, among women with CAH, we found that recalled male-typical play in childhood correlated with reduced satisfaction with the female gender and reduced heterosexual interest in adulthood. Although prospective studies are needed, these results suggest that those girls with CAH who show the greatest alterations in childhood play behavior may be the most likely to develop a bisexual or homosexual orientation as adults and to be dissatisfied with the female sex of assignment.

Hines hat sich um die Forschung auf dem Gebiet sehr verdient gemacht. ihre Forschung zeigt, dass Mädchen, die davon betroffen sind weniger zufrieden mit ihrer Rolle als Frau sind und auch eher homosexuell werden. Studien dieser Art haben leider aufgrund der Seltenheit der Krankheit den Nachteil, dass sie üblicherweise eine kleine Teilnehmerzahl haben. Umso erstaunlicher ist es, dass in diesem Bereich überhaupt Homosexualität überprüft werden kann, die bei der Bevölkerung bei Frauen ein Anteil von ca. ein Prozent hat. Die Mädchen sind unzufriedener mit ihrer Rolle, sie zeigen eher typische Spielverhalten wie bei Jungs, umso mehr sie dieses Verhalten haben umso mehr sind sie auch später unzufrieden und umso eher haben Sie weniger Interesse an heterosexuellen Sex.

Resnick et all 1986
Early hormonal influences on cognitive functioning in congenital adrenal hyperplasia.

Administered a cognitive test battery that emphasized spatial ability, verbal fluency, and perceptual speed and accuracy to 17 females (aged 12.7–23.2 yrs) and 8 males (aged 13–29.9 yrs) with congenital adrenal hyperplasia (CAH) and 13 normal female relatives (aged 11.4–31.1 yrs) and 14 unaffected male relatives (aged 12.5–28.8 yrs). In addition, 13 fathers and 15 mothers of CAH patients participated. Ss also completed the Progressive Matrices, a vocabulary test, and an early life activities questionnaire (ELAQ). Findings indicate that CAH females, as compared with normal females, showed significantly enhanced performance on hidden pattern, card rotation, and mental rotation tests of spatial ability. On the ELAQ, CAH females, relative to normal females, showed significantly lower frequencies of participation in activities involving verbal expression and a trend toward greater participation in spatial manipulation activities. However, differences between CAH females and normal females in early childhood activities did not account for observed differences in spatial ability, given the absence of a significant correlation between the spatial manipulation activity scale and spatial ability. There was an absence of reliable differences between male CAH patients and controls across spatial tasks. Results are consistent with an effect of pre- and perinatal androgenizing hormones on the development of spatial ability. (58 ref) (PsycINFO Database Record (c) 2016 APA, all rights reserved)

Also eine Studie, in der man Eigenschaften verglichen hat. Die CA H Mädchen schnitten besser ab bei Sachen die dem räumlichen Denken, mentaler Rotation und allgemein Fähigkeiten, ihres räumliche Denken betreffen. Bei sprachlichen Tests hingegen schnitten sie schlechter ab. Gleichzeitig bestand kein Zusammenhang mit besonderen Aktivitäten in der Kindheit, so dass diese insoweit als Grundlage für die Fähigkeiten ausscheiden. Eine Vielzahl von Studien weist nach, dass bei räumlichen Denken ein Geschlechterunterschied besteht und dieses mit insbesondere pränatalen Testosteron in Verbindung steht und zudem dieses wiederum insbesondere auch für Naturwissenschaften etc. eher gebraucht wird. Zudem zeigen Studien, dass Testosteron häufig mit verminderten Sprachfähigkeiten einhergeht.  Hier soll allerdings auch frühes postnatales Testosteron eine Rolle spielen.

Louise Friesen et all, 2009

Gender Role Behavior, Sexuality, and Psychosocial Adaptation in Women with Congenital Adrenal Hyperplasia due to CYP21A2 Deficiency

Context: Gender-atypical behavior has been described in young girls as well as in women with congenital adrenal hyperplasia (CAH) due to a CYP21A2deficiency.

Objective: The aim of the study was to assess health-related, psychosexual, and psychosocial parameters and correlate the results to CYP21A2 genotype.

Design and Participants: Sixty-two Swedish women with CAH and age-matched controls completed a 120-item questionnaire and a validated quality of life instrument [psychological general well-being (PGWB) formula] to identify psychosexual and psychosocial parameters. The patients were divided into four CYP21A2 genotype groups.

Results: The women with CAH held more male-dominant occupations (30%) compared to controls (13%) (P = 0.04), especially those in the null genotype group (55%) (P = 0.006). They also reported a greater interest in rough sports (74%) compared to controls (50%) (P = 0.007). Eight women with CAH (14%) reported a prime interest in motor vehicles, compared to none of the controls (P= 0.002). Non-heterosexual orientation was reported by 19% of women with CAH (P = 0.005), 50% in the null genotype group (P = 0.0001), 30% in I2splice (NS), and 5% in I172N (NS). PGWB total score did not differ between patients and controls.

Conclusion: We identified increased gender-atypical behavior in women with CAH that could be correlated to the CYP21A2 genotype. This speaks in favor of dose-dependent effects of prenatal androgens on the development of higher brain functions. The impact of the disease on upbringing and interpersonal relationships did not correlate with disease severity, indicating that other factors, such as coping strategies, are important for psychosocial adaptation. This illustrates the need for psychological support to parents and patients.

Gender-atypical behavior in Swedish women with congenital adrenal hyperplasia is correlated to their CYP21A2 genotype.

auch hier wurden wieder deutliche Unterschiede festgestellt. Im Vergleich zur Kontrollgruppe arbeiteten 30 % mehr der Frauen in einer männlich dominierten Beschäftigung, einer speziellen gehen sogar 55 % nach.

74 % berichteten, dass Sie ein großes Interesse an „härteren Sportarten“hatten, während dies lediglich bei 50 % der Kontrollgruppe der Fall war. 8 Frauen hatten ein Interesse an Kraftfahrzeugen, dagegen waren es in der Kontrollgruppe keine Frau. Zudem hatten 19 % der Frauen mit CA H eine nicht heterosexuelle Orientierung und aus der Gruppe mit dem bestimmten Genen sogar 30 %. Auch hier werden insoweit gewaltige Unterschiede deutlich.

Sheri Berenbaum, 1998

Effects of Early Androgens on Sex-Typed Activities and Interests in Adolescents with Congenital Adrenal Hyperplasia

The goal of this study was to examine the relation of early androgen exposure to sex-typed activities and interests in adolescence. Participants aged 9–19 years included 24 girls and 18 boys with congenital adrenal hyperplasia (CAH) and 16 unaffected sisters and 24 unaffected brothers who served as controls. Using standardized questionnaires, adolescents reported on their participation in sex-typed activities and interest in sex-typed occupations, and parents reported on the adolescents‘ activities. As hypothesized, girls with CAH showed sex-atypical preferences: increased interest in male-typical activities and careers and reduced interest in female-typical activities and careers compared to the unexposed control girls. These results extend findings of sex-atypical play in young girls with CAH and suggest that the sex-atypical activities and interests of females with CAH reflect direct effects of androgens on the developing brain rather than social responses to virilized genitalia. These results also suggest that population sex differences in activities and interests arise in part from sex differences in early androgens.

Auch in dieser Stunde Studie wurde deutlich, dass CH Frauen für Frauen ansonsten untypischere Präferenzen haben. Sie zeigen ein größeres Interesse an sie untypischen Tätigkeiten und Karrieren und ein reduziertes Interesse in für Frauen typische Aktivitäten und Karrieren. Zudem spielen sie anders.

Ralf Dittmann et all, 1990

Congenital adrenal hyperplasia I: Gender-related behavior and attitudes in female patients and sisters

Thirty-five female patients with congenital adrenal hyperplasia (CAH) were compared to a group of 16 healthy sisters in regard to gender-related behavioral patterns, present attitudes, and plans for the future. A semi-structured interview with the subjects, ages 11 to 41 yr, and their mothers concentrated on four to five age stages. Results of retrospective data from single items as well as from several related composite scales (“interests and behavior,” “appearance,” “overall scores”) revealed significant group differences: Both in mother-assessment and self-assessment, CAH patients showed a “more masculine” orientation than their sisters, but this was far from consistent across all age stages, especially for single items. Unexpectedly, the gender-behavior differences between CAH patients and sisters did not hold for certain items and scales of “social behavior” (e.g., assertiveness, dominance, acceptance in peer groups) and, in contrast to some of the existing literature, also not for “high-energy expenditure.” With regard to expectations for the future, CAH patients had less of a “wish to have their own children” and a higher preference for “having a career versus staying at home.”

Age, socioeconomic status, intelligence, and presence or absence of a sister as possibly intervening psychosocial/demographic factors could not explain the group differences in behavior. Degree of genital masculinization (Prader stages) or “onset and quality” of therapy as measures of pre- and postnatal androgenization, respectively, could also not account for the degree of the “more masculine” orientation in the CAH group. Nevertheless, the overall results are compatible with earlier findings on the masculinizing effects of prenatal androgens on behavior in humans and point to a time period after sexual differentiation of the genitalia and before birth as the most likely one for the effects of prenatal hormones on behavioral masculinization in humans.

Auch hier wieder eine Studie, die männlicheres Verhalten zeigt, diesem im direkten Vergleich mit Schwestern. Der Vergleich mit der Schwester dient natürlich insoweit zu, dass man bestimmte soziokulturelle Faktoren, etwa eine Beeinflussung aus dem Haushalt oder der näheren Umgebung untersucht. Hier zeigt sich, dass der Effekt auch unter diesen Gesichtspunkten zu beobachten ist. Die CA H Frauen hatten einen geringeren Wunsch nach eigenen Kindern und eine höhere Präferenz dafür, eine Karriere zu haben  statt zu Hause zu bleiben.

Jan Helleday et all, 1993

Personality characteristics and platelet MAO activity in women with congenital adrenal hyperplasia (CAH)

Personality traits and platelet monoamine oxidase (MAO) activity were studied in 22 women, 17–34 years old, with prenatal virilization due to congenital adrenal hyperplasia (CAH) (21-hydroxylase deficiency) and 22 healthy controls. The CAH group differed significantly on two of the eight scales of the Karolinska Scales of Personality (KSP), which have earlier shown significant gender differences. Both differences were in the masculine direction, with a high, male level, score for Detachment and a lower score for Indirect Aggression. The Detachment scale reflects distance in social relations, and has earlier been shown to be strongly gender differentiating. There was no significant difference in platelet MAO activity between the CAH group and the controls. Although an influence of psychosocial factors cannot be excluded, the results suggest a possible association between prenatal androgen exposure and the high Detachment score for the CAH group. Gender differences in empathy, affiliation motivation, intimacy and maternal behavior may be relevant parallels.

hier wurde also Persönlichkeitstests durchgeführt, die insbesondere auch ansonsten dazu führen, dass Geschlechterunterschiede festgestellt werden. Die CAH Mädchen weichen hier in die männliche Richtung ab, insbesondere im Bereich Distanziertheit.  zudem neigten sie weniger zu indirekter Aggression, die ansonsten bei Frauen einen höheren Wert hatten

Melissa Hines, 1994

Androgen and the Development of Human Sex‐typical Behavior: Rough‐and‐Tumble Play and Sex of Preferred Playmates in Children with Congenital Adrenal Hyperplasia (CAH)

We hypothesized that girls with congenital adrenal hyperplasia (CAH), who experience higher than normal levels of androgens prenatally, would show masculinization of behaviors that show sex differences. Therefore, we examined rough‐and‐tumble play and sex of preferred playmates in 3–8‐year‐old children with CAH and in unaffected 3–8‐year‐old male and female relatives. The hypothesized sex differences in rough‐and‐tumble play were seen, with unaffected boys showing more rough‐and‐tumble play than unaffected girls. However, CAH girls were similar to unaffected girls. Additionally, CAH boys showed reduced rough‐and‐tumble play. In contrast, sex of preferred playmates showed the hypothesized pattern of results. There were sex differences, with unaffected boys preferring boys and unaffected girls preferring girls. In addition, the preferences of girls with CAH were masculinized compared to those of unaffected girls. Results are discussed in terms of possible influences of social, hormonal, and illness factors.

Auch hier waren also die Spielpräferenzen der CAH Mädchen denen der Männer eher angeglichen und sie haben auch mit anderen Jungs gespielt.

RebeccaKnickmeyer, SimonBaron-Cohen et all, 2006

Androgens and autistic traits: A study of individuals with congenital adrenal hyperplasia

Testosterone promotes male-typical neural and behavioral development in non-human mammals. There is growing evidence that testosterone exerts similar influences on human development, although the range of behaviors affected is not completely known. This study examined the hypothesis that autistic traits are increased following prenatal exposure to abnormally high levels of testosterone caused by congenital adrenal hyperplasia (CAH). Sixty individuals with CAH (34 female, 26 male) and 49 unaffected relatives (24 female, 25 male) completed the Autism Spectrum Quotient (AQ). Females with CAH scored significantly higher than unaffected females on total AQ score, largely due to enhanced scores on subscales measuring social skills and imagination. These results suggest that prenatal exposure to high levels of testosterone influences some autistic traits and that hormonal factors may be involved in vulnerability to autism.

Simon Baron-Cohen ist ja einer der engagiertesten Vertreter der Theorie, dass Autismus eine Form von einem extrem männlichen Gehirn ist. Demnach ist es konsequent zu untersuchen, wie Mädchen mit CA H in diesem Bereich abschneiden. Wie erwartet liegen sie auf der Autismus Skala höher

Zucker et all, 1996

Psychosexual Development of Women with Congenital Adrenal Hyperplasia

Women with congenital adrenal hyperplasia (CAH) (N= 31) and their unaffected sisters or female cousins (N= 15) participated in a study of psychosexual development. All participants were ≥18 years of age (mean age, 25 years; range, 18–40). Comparisons were also made between the CAH women with the salt-wasting (SW) form of the disorder and those with simple virilization (SV). A psychosexual assessment protocol examined six variables: (1) sex assignment at birth (probands only); (2) recalled sex-typed behavior during childhood; (3) gender identity and gender role identification in adulthood; (4) relationship status; (5) sexual orientation in fantasy; and (6) sexual orientation in behavior. Salt-wasting status and sex assignment at birth were also ascertained for the CAH women who either refused to participate in the study (N= 10) or could not be traced (N= 13). Compared to the controls, the women with CAH recalled more cross-gender role behavior and less comfort with their sense of “femininity” during childhood. The two groups did not differ in degree of gender dysphoria in adulthood, although the probands showed more cross-gender role identification. Three of the nonparticipant probands were living, as adults, in the male social role (2 reared from birth as boys and 1 who changed from the female to the male social role during adolescence). The CAH women and the controls did not differ in relationship status (married/cohabiting vs. single). The CAH women had lower rates of exclusive heterosexual fantasy and fewer sexual experiences with men than the controls; however, the CAH women did not have more sexual experiences with women than the controls. Comparisons between the SW and SV revealed several differences: the SW were less likely to be assigned to the female sex at birth, recalled more cross-gender role behavior during childhood, were less likely to be married or cohabiting, and had lower rates of sexual experiences with men. The results were discussed in relation to the effects of prenatal androgens on psychosexual differentiation.

auch hier das Bild, das sich auch schon in den anderen Studien gezeigt hat. Die CAH Mädchen zeigten mehr Verhalten der männlichen Geschlechterrolle und waren weniger einverstanden mit der Bewertung von Weiblichkeit in ihrer Kindheit. Zudem waren CAH Frauen häufiger homosexuell und hatten demzufolge auch mehr sexuelle Erfahrung mit Frauen. Sie waren seltener verheiratet und lebten selten mit einem Partner zusammen und hatten weniger sexuelle Erfahrung mit Männern

Hines et all, 2003

Spatial abilities following prenatal androgen abnormality: targeting and mental rotations performance in individuals with congenital adrenal hyperplasia

In most mammals, behaviors that show sex differences are influenced by androgen during early life. In the current study, the hypothesis that androgen influences the development of human spatial abilities was investigated. Participants included 40 females and 29 males with congenital adrenal hyperplasia (CAH), a genetic disorder that causes overproduction of adrenal androgens beginning prenatally, and 29 unaffected female and 30 unaffected male relatives of individuals with CAH. Participants ranged in age from 12–45 years. Measures of spatial abilities included two mental rotations tasks and two targeting tasks, all of which showed large sex differences favoring males in the unaffected relative controls. Females with CAH (exposed to higher than normal levels of androgen prenatally) performed better than unaffected females on the targeting tasks, and resembled unaffected males and males with CAH in this respect. However, females with CAH did not perform better than unaffected females on the measures of mental rotations abilities. Males with CAH showed unaltered performance on the targeting tasks, and impaired performance on the mental rotations tasks. Results are discussed in terms of differences in experiential and hormonal contributions to different spatial abilities, as well as in terms of possible differences in critical periods for hormonal influences on targeting versus mental rotations abilities. Specifically, we speculate that, although androgen may influence targeting abilities prenatally, if hormones influence the development of mental rotations ability, they do so at some other time, perhaps during the first six months of postnatal life.

auch hier wird wieder der Unterschiede festgestellt, die CAH Mädchen hatten eher Leistungen, die denen der Männern entsprachen.

Servin et all, 2016

Prenatal androgens and gender-typed behavior: A study of girls with mild and severe forms of congenital adrenal hyperplasia.

Gender-typed behaviors and interests were investigated in 26 girls, aged 2-10 years, affected with congenital adrenal hyperplasia (CAH) and in 26 unaffected girls matched for age. Girls with CAH were more interested in masculine toys and less interested in feminine toys and were more likely to report having male playmates and to wish for masculine careers. Parents of girls with CAH rated their daughters‘ behaviors as more boylike than did parents of unaffected girls. A relation was found between disease severity and behavior indicating that more severely affected CAH girls were more interested in masculine toys and careers. No parental influence could be demonstrated on play behavior, nor did the comparison of parents‘ ratings of wished for behavior versus perceived behavior in their daughters indicate an effect of parental expectations. The results are interpreted as supporting a biological contribution to differences in play behavior between girls with and without CAH

und auch hier immer wieder das gleiche Bild. Mädchen mit CAH interessieren sich eher für Spielzeug, mit dem sonst Jungs spielen und sind weniger interessiert an Spielzeug, mit den sonst Mädchen spielen. Sie spielen lieber mit Jungs und sie stellen sich Karrieren vor, die sich sonst eher Jungs vorstellen. Die Eltern bewerten auch das Verhalten ihrer Töchter mit CAH eher als typisch für Jungs, gleichzeitig wurde kein elterliche Einfluss festgestellt und auch keine Übereinstimmung damit, was die Eltern gerne als Verhalten bei dem Kind gehabt hätten.

Nordenström et all, 2002

Sex-Typed Toy Play Behavior Correlates with the Degree of Prenatal Androgen Exposure Assessed by CYP21 Genotype in Girls with Congenital Adrenal Hyperplasia 

Previous studies have shown that girls with congenital adrenal hyperplasia (CAH), a syndrome resulting in overproduction of adrenal androgens from early fetal life, are behaviorally masculinized. We studied play with toys in a structured play situation and correlated the results with disease severity, assessed by CYP21 genotyping, and age at diagnosis. Girls with CAH played more with masculine toys than controls when playing alone. In addition, we could demonstrate a dose-response relationship between disease severity (i.e. degree of fetal androgen exposure) and degree of masculinization of behavior. The presence of a parent did not influence the CAH girls to play in a more masculine fashion. Four CAH girls with late diagnosis are also described. Three of the four girls played exclusively with one of the masculine toys, a constructional toy. Our results support the view that prenatal androgen exposure has a direct organizational effect on the human brain to determine certain aspects of sex-typed behavior.

in dieser Studie wurde das Ergebnis, dass die Kinder dann lieber mit männlichen Spielzeug spielen bestätigt und es wurde zudem festgestellt, dass auch eine Übereinstimmung mit der Menge an pränatalen Androgenen besteht.

Meyer-Bahlburg et al, 2008

Sexual Orientation in Women with Classical or Non-classical Congenital Adrenal Hyperplasia as a Function of Degree of Prenatal Androgen Excess

46,XX individuals with classical congenital adrenal hyperplasia (CAH) due to deficiency of the enzyme, 21-hydroxylase, show variable degrees of masculinization of body and behavior due to excess adrenal androgen production. Increased bisexuality and homosexuality have also been reported. This article provides a review of existing reports of the latter and presents a new study aimed at replicating the previous findings with detailed assessments of sexual orientation on relatively large samples, and at extending the investigation to the mildest form, non-classical (NC) CAH. Also, this is the first study to relate sexual orientation to the specific molecular genotypes of CAH. In the present study, 40 salt-wasters (SW), 21 SV (simple-virilizing), 82 NC, and 24 non-CAH control women (sisters and female cousins of CAH women) were blindly administered the Sexual Behavior Assessment Schedule (SEBAS-A, 1983 ed.; H. F. L. Meyer-Bahlburg & A. A. Ehrhardt, Privately printed). Most women were heterosexual, but the rates of bisexual and homosexual orientation were increased above controls not only in women with classical CAH, but also in NC women, and correlated with the degree of prenatal androgenization. Classifying women by molecular genotypes did not further increase the correlation. Diverse aspects of sexual orientation were highly intercorrelated, and principal components analysis yielded one general factor. Bisexual/homosexual orientation was (modestly) correlated with global measures of masculinization of non-sexual behavior and predicted independently by the degree of both prenatal androgenization and masculinization of childhood behavior. We conclude that the findings support a sexual-differentiation perspective involving prenatal androgens on the development of sexual orientation.

und in dieser Studie geht es um den Nachweis, dass auch die sexuelle Orientierung mit der Dosis an Androgenen korreliert.

 

Testo-kain oder Koka-steron? Zur Wirkung von Testosteron

Dies ist ein Gastartikel von Nina Radtke

Vor nicht all zu langer Zeit habe ich Testosteron mit Kokain verglichen. Zu diesem Schluss bin ich gekommen, da ich, im Gegensatz zu den meisten Menschen, in meinem Leben bereits verschiedenste Mengen an Testosteron im Blut hatte.

Dazu muss ich nun erst einmal kurz meine Vorgeschichte erklären: Bis ich 21 wurde, war ich der männlichen Adoleszenz unterworfen. Je mehr die Männlichkeit mein Ich bestimmte, umso schlechter fühlte ich mich. Das lag allerdings an meinem inneren Konflikt, dem Umstand, das ich trotz bereits lange vorher bestehendem andersartigem Bedürfnis, ein Mann werden sollte statt eine Frau.

Nun, ich habe dann, zuerst in Eigenregie und später mit ärztlicher Unterstützung eine Hormontherapie begonnen (und viele Operationen mitgemacht), dabei war mein Androgenspiegel oft signifikanten Änderungen unterworfen und ich habe inzwischen Alles erlebt von Testosteron quasi auf 0 bis hin zu den furchtbar hohen Testosteronspiegeln die ich angesichts meiner damals sehr ausgeprägten Muskulatur und Maskulinität gehabt haben muss.

Natürlich ist Testosteron nur ein Faktor, auch die Östrogenspiegel sowie mein weiterer Lebensweg hatten und haben sicher einen Einfluss auf mein Verhalten.

Dennoch ist es meine persönliche Empfindung, das Testosteron / Dihydrotestosteron (Wird mit Hilfe einer Aromatase zB in Prostata und Haarfolikeln aus Testosteron hergestellt und wirkt deutlich stärker) folgendermaßen wirkt:

  • Testosteron gibt Selbstvertrauen
    Wenn mein Testosteronspiegel sehr sehr niedrig ist, dann geht mir zunehmend das Selbstvertrauen flöten. Als mein Testosteronspiegel deutlich höher war, hatte ich im Umgang mit Menschen keine Selbstzweifel. Und auch keine Selbstzweifel (nur Verbitterung) beim Blick in den Spiegel. Bei sehr niedrigem Testosteron fühle ich mich einfach nicht sicher, aber es ist mehr. Mit viel Testosteron hat mein Selbstvertrauen oft dazu geführt, das Leute ohne Wiederworte Dinge mitgemacht haben, um die ich sie jetzt wirklich bitten müsste. Ich stand auch sehr viel mehr im Mittelpunkt.
  • Testosteron macht aktiv
    Kaum Testo – Lange Schlafen | „Normales Testo“ (Wert den ich die meiste Zeit hatte, etwas über weibl. Norm) – Halbwegs Aktiv | Hohes Testo – Aufgedreht (zB hin und her laufen beim Warten) ——- Hab aber glaub ich auch ADHS was sich überwiegend in sprunghaften Gedanken aber auch in physischer Unruhe äußert
  • Testosteron macht Unangreifbar
    Keine Angriff hätte mein Ego treffen können. Sowieso ist Ego glaube ich ein Produkt des zirkulierenden Testosterons, jedenfalls hat der Wettbewerbsgeist und der Geltungswahn mit der Hormontherapie schrittweise abgenommen und hat nun (T < weibliche Norm) Nichts mehr zu sagen. Ich bin jetzt auf mein Potential fokussiert und nicht auf den Vergleich mit Anderen. Ich ordne mich ohne Hierachiebewusstsein in eine Gruppe ein, früher undenkbar, aber vielleicht war mein Fokus auf Hierachie auch teilweise durch die Tipps in den Flirtratgebern statt nur durchs Testosteron bestimmt.
  • Testosteron macht Triebhaft
    Drogen, Party, Alkohol, Fressen – früher konnte ich mir den Driss jeden Tag geben und habs auch getan weil ich immer Bock drauf hatte. Eine neurobiologische Erklärung könnte sein, das Testosteron die Dopaminausschüttung stimuliert: Der gleiche Belohnungsreiz wirkt mit viel Testosteron deutlich stärker als mit wenig Testosteron. Vermutlich ein Grund, warum exzessives Verhalten bei Männern verbreiteter ist: Mehr Dopamin = Mehr Risikobereitschaft.
  • Testosteron macht gefühllos
    Schlimmer als unter Antidepressiva hat das Testosteron damals wie eine unsichtbare Mauer meine Gefühle eingesperrt. Ich konnte Gefühle ansatzweise fühlen, aber es gab immer einen Punkt, wo die Gefühle geblockt waren. Nur besonders starke „Einschläge“ konnten mich emotional aus der Ruhe bringen. Emotionen sind unter Östrogen ohne Testosteron weit fließender und natürlicher.

Mehr kann ich dazu nicht sagen, es ist noch heftig wie stark anabol Testosteron wirkt, ich merke es innerhalb weniger Wochen wenn mein Testosteron mal wieder sinkt oder steigt, das die Einkaufstasche mal schwerer und mal leichter ist. Aber das weiß glaub ich Jeder über das Hormon Testosteron^^

Zur Ergänzung des Gastartikels noch einige Links:

„Es ist nicht möglich festzustellen, was biologischer und was sozialer Anteil ist“

Ein Argument, welches in Diskussionen gerne kommt, ist, dass es quasi unmöglich ist zu sagen, was der biologische Anteil eines Verhaltens ist und was der soziale Anteil:

Hier kommt das Argument beispielsweise von Maren:

Die einzelnen Einflüsse sind schwer zu untersuchen/unterscheiden, weil auf Kinder/Erwachsene täglich so eine Masse an Informationen einströmt, und weil Menschenversuche unethisch sind. Von daher ist es relativ unklar, welche Aspekte biologisch und welche sozial bedingt sind.

Ich meine auch Joachim verwendet es des häufigeren, finde aber gerade keine passende Stelle.

Meiner Meinung nach ist das so nicht richtig. Oder würde jedenfalls dazu führen, dass man auch in der gesamten Soziologie keinerlei Theorien dazu aufstellen könnte, wodurch ein bestimmtes Geschlechterverhalten hervorgerufen wird. Denn wenn man dort eine gewisse Korrelation zu einem Erziehungsstil feststellt, dann muss man ja auch in irgendeiner Form diesen Erziehungsstil gewichten und und einordnen und dann die Auswirkungen zuordnen. Wenn man also zB feststellt, dass Erziehungsstil Y ein Verhalten auf einer Skala von 1 (weiblich) zu 5 (männlich) von 5 hervorruft, dann kann man eben auch biologische Faktoren hierzu in Bezug setzen. Wie reagieren dann Mädchen mit einem pränatalen Testosteronlevel von 10 statt den zB für Mädchen üblichen 1 auf den genau gleichen Erziehungsstil Y, den man vorher noch genau einordnen konnte? Zeigen sich hier deutliche Abweichungen untereinander, die in einer Übereinstimmung mit der Höhe des Testosteronspiegels sind, dann kann man zumindest eine entsprechende Korrellation feststellen. Überprüft man dann noch, ob Mädchen mit eine, pränatalen Testosteronlevel von 10 sich äußerlich stark von solchen mit einem pränatalen Testosteronlevel von 1 optisch abweichen und kommt man zu dem Ergebnis, dass das nicht der Fall ist, dann spricht alles dafür, dass der Testosteronlevel sich entsprechend auswirkt.

Wer nun anfängt, dass hier aber weitere ungeklärte Umstände vorliegen können, die das Ergebnis bewirken, der muss dies eben auch bezüglich der Erziehungsstile gelten lassen.

Sprich: Um so mehr Genauigkeit man der Forschung zum sozialen Anteil zubilligt um so mehr Genauigkeit muss man auch der Abgrenzbarkeit von sozialen und biologischen Faktoren zusprechen.

Androgenzeptoren und Verhalten

John Mannings Buch „The Finger Book“ enthält neben vielem zur Digit Ratio auch einen interessanten Beitrag zur Arbeitsweise der Androgenrezeptoren:

Testosterone influences the expression of many genes which in turn influence other genes, and so it has an immensely influential „cascade“ effect on the body. However, before this cascade can be activated testosterone must first bind to a receptor molecule, the androgen receptor; the hormone receptor complex then exerts its effect on the genes. The androgen receptor is therefore very important, as its structure determines our sensitivity to testosterone. Hte andorgen receptor is a protein which, in common with all other proteins, is made up of building blocks known as amino acids. One such amino acid, glutamine, is found in large numbers i an particular part of the receptor molecule. it is the length of this glutamine chain that is important in determining our sensitivity to testosterone. In general the average number of glutamines per receptor molecule is around twenty to twenty-two, altough the normal range is from eleven to thirty. If you have eleven glutamines ypur testosterone-receptor complex is very effective in switching on the testosterone cascade, but as the number of glutamines increases the sensitivity to testosterone reduces, so that an individual with thirty glutamines will have mild testosterone insensitivity.

Eine schwerer Form wäre es, wenn der Körper aufgrund sehr zahlreicher Wiederholungen überhaupt kein Testosteron mehr erkennt (CAIS). Eine andere Beschreibung habe ich auch noch hier gefunden:

The trait of interest in this article affects the transcription, or message-relaying effect of the androgen receptor. The androgen receptor binds testosterone normally, and travels to the cell nucleus (where the DNA is compartmentalized), but is unable to turn on and off the appropriate cell functions to the same degree as men who are more androgenized.

This trait, called the CAG repeat polymorphism (CAG), refers to a glutamine-tag attached to the androgen receptor. CAG refers to the DNA sequence of the gene that produces the androgen receptor.7 It takes three nucleotides (the building-block units of DNA) to code for one amino acid in protein chain; CAG is the sequence of cytosine-adenine-guanine, which codes for the amino acid glutamine.

Ironically, the androgen receptor gene is located on the X chromosome, which necessarily comes from the mother (assuming you are a male). Called the ‘sex chromosomes,’ females have 2 X (or XX), while men have an X and a Y (XY). One might think men who carry an extra X chromosome (XXY), a syndrome called Klinefelter’s, might be at an advantage— but in reality, these men have low serum (blood) testosterone concentration, small testicles, suffer from infertility, and are prone to gynecomastia.

The CAG would not appear to have a function, coding for a redundant stretch of glutamine inserted in a receptor that is otherwise identical to the androgen receptor of all normal men. However, as has been readily demonstrated, the longer the glutamine chain, the less efficient the androgen receptor is at turning on or off the genes that create the healthy male physiology. (…)

When testosterone enters a cell (for the biology geeks, this is restricted to the genomic effects of testosterone), it binds with an androgen receptor. There are different co-factors in the various cell types (skeletal muscle, fat, liver, etc.) that either enhance or impair the ability of the receptor to connect with and stimulate the cell to respond.9 These co-factors attach onto the testosterone-androgen receptor complex and travel as a unit to the nucleus, and bind to the chromosomes (DNA) at specific androgen response elements— think of it as assigned parking spaces. The complex then dimerizes (pairs up with another complex) to actually turn on the testosterone-sensitive genes.

Genes are information; they do not function as anything other than data storage. In order for the information they contain to become new cell structures or change function, the information has to re-enter the cell in a form that the machinery of the cell can understand. This occurs through transcription. Transcription creates a ‘chemical memo,’ or instructions from the head office. The longer the CAG repeat, the higher the degree of separation, and the less likely the message is to be affected.

Eine interessante Studie zu Hormonrezeptoren und Transsexualität ist die Folgende:

Studies of genetic males with single gene mutations that impair testosterone formation or action and consequently prevent development of the normal male phenotype provide unique insight into the control of gender role behavior. 46,XY individuals with either of two autosomal recessive mutations [17β-hydroxysteroid dehydrogenase 3 (17β-HSD3) deficiency or steroid 5α-reductase 2 (5α-R2) deficiency] have a female phenotype at birth and are raised as females but frequently change gender role behavior to male after the expected time of puberty. In contrast, genetic males with mutations that impair profoundly the function of the androgen receptor are also raised as females and have consistent female behavior as adults. Furthermore, the rare men with mutations that impair estrogen synthesis or the estrogen receptor have male gender role behavior. These findings indicate that androgens are important determinants of gender role behavior (and probably of gender identity) and that this action is mediated by the androgen receptor and not the result of conversion of androgen to estrogen. The fact that all genetic males with 17β-HSD3 or 5α-R2 deficiency do not change gender role behavior indicates that other factors are also important determinants of this process.

Quelle: Androgens, Androgen Receptors, and Male Gender Role Behavior

Zur Transsexualität hatte ich auch in dem Artikel „Transsexualität, Androgenrezeptoren und Gene“ etwas geschrieben.

Die Wirkung der Androgenrezeptoren wirkt sich auch auf die Digit Ratio aus:

The second to fourth digit ratio (2D:4D) is sexually dimorphic, with lower mean values in males compared to females. It has been suggested that the sex difference in 2D:4D is determined prenatally, 2D:4D is negatively related to prenatal testosterone and positively to prenatal oestrogen, and that 2D:4D is a marker for levels of sex steroids during brain organisation. There is growing evidence that many sex-dependent behaviours are correlated with 2D:4D. However, there is no direct evidence for an effect of prenatal sex steroids on the digit ratio. The response to prenatal testosterone is dependent on the amount produced and the foetal sensitivity to the hormone. Variation in the X-linked androgen receptor gene (AR) determines sensitivity to testosterone. Alleles of AR with low numbers of CAG triplets respond to testosterone with high transactivational activity, while high numbers of CAG’s are associated with increased insensitivity to testosterone. We show in a sample of 50 men (49 Caucasian subjects, 1 Caucasian/Chinese subject) that 2D:4D is a phenotypic correlate of AR structure. Right-hand 2D:4D was positively correlated with CAG number and individuals with low 2D:4D in their right hand compared to left hand had AR alleles with low CAG numbers. We discuss the implications of our findings for our understanding of the aetiology of 2D:4D, its relationships with sex-dependent behaviours, and the evolutionary implications of variation in 2D:4D and AR.

Quelle: The second to fourth digit ratio and variation in the androgen receptor gene (Manning)

Wenn man dann bedenkt, dass die Digit Ratio mit für das Geschlecht typischen Verhalten in Verbindung steht, dann wird deutlich, dass diese Faktoren Auswirkungen haben.

Auch in Tieren läßt sich ein Zusammenhang von Testosteron, den Rezeptoren und Verhalten nachweisen:

The purpose of this study was 2-fold: 1) to use gonadal steroid hormone exposures in the physiological range to assess the relative roles of testosterone (T), estradiol (E2), and dihydrotestosterone (DHT) in the expression of male sexual behavior, and 2) to determine whether androgen receptor (AR) or estrogen receptor (E2R) occupation is increased after exposure to these various gonadal steroid hormones. Sexually experienced, castrated male rats implanted sc with Silastic capsules containing T, 10% E2, DHT, 10% E2 plus DHT, or blanks provided hormone levels in the physiological range. Copulatory behavior was measured on days 2–4, 5–7, 10–12, and 14–16 of steroid treatment. Although T, E2, and E2 plus DHT treatments all activated mounting, only T was effective in restoring ejaculation in 100% of the males. DHT alone had no effect on any aspect of male sexual behavior. Brains of males given these various hormone treatments were assayed for both cell nuclear AR and cell nuclear E2R binding in the hypothalamus, preoptic area, amygdala, and septum. Results indicate that when hormone levels in the physiological range were employed, T and DHT bind primarily to AR, whereas E2 binds to E2R. In a second experiment, 0.5% E2 plus DHT was found to yield AR and E2R levels comparable to those in rats receiving T capsules. Male rats bearing these capsules showed virtually no sexual behavior, demonstrating that elevation of AR and E2R levels comparable to those generated by T is not sufficient to induce male sexual behavior. We then measured intact AR and E2R levels and determined that in intact males E2R levels were higher than in T-treated males. These E2R levels could be replicated using 1.0% E2. Males exposed to 1.0% E2 plus DHT failed to display male sexual behavior. These data suggest that 1) relatively high and prolonged levels of E2R occupation are required for estrogen activation of male sexual behavior, 2) high levels of AR occupation induced by DHT are not sufficient to activate male sexual behavior, and 3) in intact male rats T, acting via androgen receptors, plays a primary role in mediating the expression of masculine sexual behavior. (Endocrinology 124: 618–626,1989)

Quelle: Evidence for a Role of Testosterone-Androgen Receptor Interactions in Mediating Masculine Sexual Behavior in Male Rats

Und zu den körperlichen Effekten der verschiedenen Stärken der Rezeptoren:

The androgen testosterone and its metabolite dihydrotestosterone exert their effects on gene expression and thus effect maleness via the androgen receptor (AR). A diverse range of clinical conditions starting with complete androgen insensitivity has been correlated with mutations in the AR. Subtle modulations of the transcriptional activity induced by the AR have also been observed and frequently assigned to a polyglutamine stretch of variable length within the N-terminal domain of the receptor. This stretch is encoded by a variable number of CAG triplets in exon 1 of the AR gene located on the X chromosome. First observations of pathologically elongated AR CAG repeats in patients with X-linked spino-bulbar muscular atrophy showing marked hypoandrogenic traits were supplemented by partially conflicting findings of statistical significance also within the normal range of CAG repeat length: an involvement of prostate tissue, spermatogenesis, bone density, hair growth, cardiovascular risk factors and psychological factors has been demonstrated. The highly polymorphic nature of glutamine residues within the AR protein implies a subtle gradation of androgenicity among individuals within an environment of normal testosterone levels providing relevant ligand binding to ARs. This modulation of androgen effects may be small but continuously present during a man’s lifetime and, hence, exerts effects that are measurable in many tissues as various degrees of androgenicity and represents a relevant effector of maleness. It remains to be elucidated whether these insights are important enough to become part of individually useful laboratory assessments.

Quelle: The CAG repeat polymorphism within the androgen receptor gene and maleness

Die Unterschiedlichen Wirkungsgrade zeigen auch, dass auch innerhalb der Biologie alle Typen, von sehr geschlechtertypisch bis zu sehr untypisch vorhanden sein können.

Eine andere Studie stellt eine Verbindung zu Verbrechen her:

Androgens mediate their functions through androgen receptors (AR). The two triplet repeats in the AR gene (CAG and GGN) are highly polymorphic among various populations and have been extensively studied in diverse clinical conditions and antisocial personality disorders. Several studies have reported either higher levels of testosterone among rapists or the correlation of shorter CAG repeats with criminal activities. However, to date, no study has analyzed AR gene in rapists worldwide, and no study has been conducted on criminals from Indian subcontinent. Therefore, we have analyzed the AR-CAG repeat length in 645 men, of which 241 were convicted for rape, 107 for murder, 26 for both murder and rape, and 271 were control males. The aim was to explore if there was any correlation between CAG repeat length and criminal behavior. The study revealed significantly shorter CAG repeats in the rapists (mean 18.44 repeats) and murderers (mean 17.59 repeats) compared to the control men (mean 21.19 repeats). The criminals who committed murder after rape had a far shorter mean repeat length (mean 17.31 repeats) in comparison to the controls or those convicted of rape or murder alone. In short, our study suggests that the reduced CAG repeats in the AR gene are associated with criminal behavior. This, along with other studies, would help in understanding the biological factors associated with the antisocial or criminal activities.

Quelle: Reduced CAG repeats length in androgen receptor gene is associated with violent criminal behavior

Das passt zu den Ergebnissen, dass ein hoher Testosteronwert sich auf die Empathie auswirken kann. Bei einigen schlägt dann vielleicht diese niedrigere soziale Angepaßtheit, die daraus resultiert, in Gewalt um.

Zu den Auswirkungen pränataler Hormone vergleiche auch: Pränatales Testosteron und „genderbezogenes Verhalten“

Testosteron und Kooperation

Eine interessante Studie zur Wirkung von Testosteron auf Frauen:

Collaboration can provide benefits to the individual and the group across a variety of contexts. Even in simple perceptual tasks, the aggregation of individuals‘ personal information can enable enhanced group decision-making. However, in certain circumstances such collaboration can worsen performance, or even expose an individual to exploitation in economic tasks, and therefore a balance needs to be struck between a collaborative and a more egocentric disposition. Neurohumoral agents such as oxytocin are known to promote collaborative behaviours in economic tasks, but whether there are opponent agents, and whether these might even affect information aggregation without an economic component, is unknown. Here, we show that an androgen hormone, testosterone, acts as such an agent. Testosterone causally disrupted collaborative decision-making in a perceptual decision task, markedly reducing performance benefit individuals accrued from collaboration while leaving individual decision-making ability unaffected. This effect emerged because testosterone engendered more egocentric choices, manifest in an overweighting of one’s own relative to others‘ judgements during joint decision-making. Our findings show that the biological control of social behaviour is dynamically regulated not only by modulators promoting, but also by those diminishing a propensity to collaborate.

Quelle: Testosterone disrupts human collaboration by increasing egocentric choices (Full Text, PDF)

Aus der Diskussion in der Studie:

Our finding that testosterone increased egocentric choices accords with a broader literature concerning testosterone’s role in social choice, and in particular with an interpretation of that literature which proposes that testosterone’s role is to increase dominance or status-related behaviours [18,19]. High social status is associated with elevated testosterone in humans [13,19], chimpanzees [34] and other mammals [35]. A greater drive for social status leading to greater assertiveness during social interactions might reasonably be expected to impair an individuals’ ability to appropriately weight the opinion of another, consistent with our findings. Indeed, the increased egocentricity in an individual’s choices that we observe could be interpreted as a form of signalling, whereby the individual is signalling their dominance in the context of a collective decision. Increased dominance can be detrimental to collaborative decision-making, as shown previously during reasoning tasks where high variance in the verbal contributions of group members (i.e. groups with highly dominant individuals) led to a significantly attenuated performance benefit from collaboration [6]. Other possible effects of testosterone previously related to its role in status-related behaviour [18] may also contribute to less effective information aggregation in our dyads, for example in reducing trustworthiness ratings of faces [17] and decreasing the ability to infer emotional states through photographs of eyes [16]. In addition to potential status-related effects of testosterone, our finding of increased egocentricity has interesting parallels with testosterone’s role in sexual and reproductive behaviours, where testosterone relates to more self-orientated behaviour as evident in reduced parenting and increased courtship in birds [31,32], rodents [36] and rural Senegalese men [37]. Importantly, our task involves no conflict over resources as accurate integration of information is in the best interest of the dyad members, which suggests that the effects of testosterone we observed are not caused by it rendering individuals more selfish.

Und etwas später:

Social animals reap benefits from collaboration across a wide variety of tasks, ranging from those involving information aggregation (as seen here), reasoning [6] or the division of resources such as food or money [1–3]. Indeed, the potential benefits frominformation aggregation, for example, are used to support the use of juries (i.e. groups of observers) in the criminal justice system [5]. However, collaborating too freely is not always beneficial, and therefore the biological mechanisms controlling the balance between more collaborative and self-oriented behaviours must dynamically tune behaviour to the social environment. While a previous focus has been on factors promoting collaboration [9–11], here we highlight an opposing biological influence that increases self-orientated or status-related behaviours at the expense of collaboration. Our data show that the humoral agent testosterone modulates the delicate trade-off between collaboration and a more egocentric disposition.

Es scheint also, als würde Testosteron eine gewisse Wirkung haben, die sich in der Zusammenarbeit, zumindest bei Frauen auswirkt. Interessant ist, dass die Forscher hier selbst betonen, dass es in der Sache um nichts ging und das dies vielleicht Auswirkungen gehabt haben könnte. Eine andere Studie in der es um Verhandlungen ging, hat im Gegensatz dazu feststellt, dass Frauen, die Testosteron erhielten, fairer waren und daher besser miteinander verhandeln konnten.

Aus einer Besprechung der Studie in der Süddeutschen:

Bei dieser Abwägung sorgt Testosteron dafür, dass die eigenen Interessen nicht zu kurz kommen, wie die Forscher zeigten. In Zweierteams sollten sich die Probandinnen einigen, welches von zwei Bildschirm-Mustern die stärkeren Kontraste aufwies. Die Muster wurden kurz hintereinander präsentiert, und die Unterschiede waren sehr gering.

Dabei waren die Probandinnen ohne Testosteron deutlich im Vorteil. Sie diskutierten unvoreingenommener darüber, was jede von ihnen wahrgenommen hatte, und waren eher bereit, sich die Meinung der Partnerin anzuhören. In der Testosteron-Gruppe hingegen war eine solche Abstimmung die Ausnahme. Frauen, zuvor eine Hormonpille geschluckt hatten, ließen sich kaum von ihrer Meinung abbringen. Das egozentrische Verhalten führte zu deutlich schlechteren Trefferquoten als in der Placebo-Gruppe.

Wie eine frühere Studie gezeigt hat, kann Testosteron jedoch auch die Bereitschaft zur Kooperation erhöhen – aber nur, wenn sich die Beteiligten dadurch materielle Gewinne oder gesellschaftliches Ansehen erhoffen. Testosteron führt nämlich auch dazu, dass Menschen solche Verdienste stärker schätzen. In den Londoner Versuchen hingegen gab es keinerlei Belohnung für die richtige Antwort.

Es scheint also, also würde Testosteron insbesondere das Festhalten an der eigenen Meinung fördern, was eine Kooperation ohne besonderes Ziel erschweren kann. Ohne Testosteron schien die Bestätigung der eigenen Meinung egaler zu sein, was dann die Zusammenarbeit förderte. Es wäre interessant inwiefern das Ergebnis inbesondere bei Frauen auftritt oder aber auch auf Männer übertragbar ist.

Empathie, Testosteron und Digit Ratio

In einer Studie geht es darum, wie Testosteron bei Frauen die Empathie beeinflusst. Sowohl freies als auch pränatales Testosteron (gemessen über die Digit Ratio) führte zu einer Verminderung der Empathiefähigkeit.

During social interactions we automatically infer motives, intentions, and feelings from bodily cues of others, especially from the eye region of their faces. This cognitive empathic ability is one of the most important components of social intelligence, and is essential for effective social interaction. Females on average outperform males in this cognitive empathy, and the male sex hormone testosterone is thought to be involved. Testosterone may not only down-regulate social intelligence organizationally, by affecting fetal brain development, but also activationally, by its current effects on the brain. Here, we show that administration of testosterone in 16 young women led to a significant impairment in their cognitive empathy, and that this effect is powerfully predicted by a proxy of fetal testosterone: the right-hand second digit-to-fourth digit ratio. Our data thus not only demonstrate down-regulatory effects of current testosterone on cognitive empathy, but also suggest these are preprogrammed by the very same hormone prenatally. These findings have importance for our understanding of the psychobiology of human social intelligence.

Quelle: Testosterone administration impairs cognitive empathy in women depending on second-to-fourth digit ratio

Testosteron wirkt sich also nach dieser Forschung sowohl bei der ersten „Gehirnformatierung“ durch Testosteron aus als auch später bei dem Testosteronspiegel. Zumindest die im Gesicht erkennbare Empathie scheint davon betroffen zu sein.

Testosteron, Soziales Verhalten und Fairness

Eine interessante Studie zur Wirkung von Testosteron:

Both biosociological and psychological models, as well as animal research, suggest that testosterone has a key role in social interactions. Evidence from animal studies in rodents shows that testosterone causes aggressive behaviour towards conspecifics. Folk wisdom generalizes and adapts these findingsto humans, suggesting that testosterone induces antisocial, egoistic, or even aggressive human behaviours. However, many researchers have questioned this folk hypothesis, arguing that testosterone is primarily involved in status-related behaviours in challenging social interactions, but causal evidence that discriminates between these views is sparse. Here we show that the sublingual administration of a single dose of testosterone in women causes a substantial increase in fair bargaining behaviour, thereby reducing bargaining conflicts and increasing the efficiency of social interactions. However, subjects who believed that they received testosterone—regardless of whether they actually received it or not—behaved much more unfairly than those who believed that they were treated with placebo. Thus, the folk hypothesis seems to generate a strong negative association between subjects’ beliefs and the fairness of their offers, even though testosterone administration actually causes a substantial increase in the frequency of fair bargaining offers in our experiment.

Testosteron führt also im menschlichen Bereich dazu, dass insbesondere auf einen gerechten Austausch geachtet wird und bestimmte Regeln der Fairness eingehalten werden.

Ich vermute, dass der Effekt insbesondere aufgetreten ist, um intrasexuelle Aggression, also Aggression unter Männern, zurückzuschrauben. Männliche Aggression wurde häufig durch solche Regeln im Saum gehalten. Beispiele sind Ehrenkodexe bei Duellen, fairer Kampf etc. Testosteron mag zwar mit mehr Neigung zum Wettbewerb in Verbindung stehen, aber es schärft auch das Statusbewußtsein und das Hierarchiebewußtsein, was ebenfalls der Konfliktkontrolle gilt.