Alcohol and nicotine intake and prenatal level of androgens measured by digit ratio

The purpose of this study was to examine the associations between using unhealthy substances and the digit ratio (2nd to 4th digit length ratio, 2D:4D) which is supposed to indicate the prenatal testosterone level. The subjects were 455 students, 225 women and 230 men. Participants declared their frequency of smoking and alcohol drinking. There was no significant difference in digit ratios between subjects regularly using both nicotine and alcohol and those who took none of them. When analyzing the two substances separately, there was no relationship between 2D:4D and alcohol drinking, whereas left hand 2D:4D was positively related to smoking only for women (nonsignificant trend was observed for right hand). Contrary to the previous study, our results indicate that there is no relationship between 2D:4D and alcohol drinking. There is, however, a subtle influence of prenatal testosterone levels for cigarette smoking habits in the case of women.     

Foetal trauma,body memory and early infant communication: a case illustration

This paper presents the complex case of a male patient who started life as an unwanted pregnancy and adoptee in an era of socio‐cultural shame and blame. When able to contact his birth mother later in life, he experienced a number of confronting synchronicities as well as visions which he felt were related to failed abortion attempts and to other pre‐ and post‐natal events. The case material lends weight not only to Freud's, Ehrenwald's and FitzHerbert's assertions that the earliest form of mother‐infant communications is telepathic in nature but that this mode of communication can be retained if emotional trauma inhibits normal developmental processes. Contemporary neuroscience research is presented supporting the hypothesis that emotional memory can become imbedded in the psyche/soma of the foetus. Such memory traces can later emerge into imagery and/or words if the traumatic impingement has been substantial enough and if other defensive strategies are in place. Clinical implications are then suggested regarding analysts’ attention to the emotional conditions underpinning their patients’ conceptions and foetal development; the connection to projective identification components of the countertransference as being aspects of the earliest telepathic mother/infant communication channel and the need for reductive analyses in analyst training programmes.     

Testosterone,Risk Taking,and Religiosity: Evidence from Two Cultures

Miller and Stark (2002) argued that worldwide tendencies for males to be less religious than females must have a physiological foundation. In the same year, Stark (2002) proposed that males are more prone to risk taking than females (thereby becoming less religious) due to their higher testosterone levels. The present study was undertaken to assess the merits of these proposals using questionnaire data obtained from Malaysian and U.S. college students. Seven religiosity traits were factor analyzed into a single factor, two risk‐taking traits were averaged into a single variable, and five traits were factor analyzed into two factorial measures of androgens. The usual gender differences in religiosity and risk taking were confirmed. However, contrary to Miller and Stark's suggestion, risk taking was not found to be inversely correlated with religiosity. Regarding the two androgen factors, most of the findings were inconsistent with Stark's proposal that negative correlations would be found. Aside from females being more religious and less prone to take risks than males, most of the other theoretical ideas offered by Miller and Stark were not supported by findings from this study.     

The 2nd to 4th digit ratio (2D:4D) and eating disorder diagnosis in women

Eating disorders are more common in females than in males and are believed to be caused, in part, by biological and hormonal factors. Digit ratio or 2D:4D (the ratio of the 2nd to the 4th digit) is considered to be a proxy for prenatal testosterone (PT) and prenatal oestrogen (PE) exposure. However, how 2D:4D may be related to type of eating pathology is unknown. The relationship between 2D:4D and eating disorder diagnosis was investigated in recovered and currently eating disordered (n = 31) and control (n = 99) women. Mean 2D:4D ratio was significantly lower (indicating higher levels of PT and lower levels of PE) in anorexic (AN) compared to bulimic (BN) women, with controls intermediary. In eating disordered women, 2D:4D was positively and significantly related to current weight, lowest weight and current BMI, with strongest associations for right 2D:4D. Among women, low 2D:4D is related to AN and high 2D:4D to BN, suggesting a differential causal influence of prenatal sex hormones on later eating pathology.     

Importance of considering testosterone-cortisol interactions in predicting human aggression and dominance

A novel "field" study recently published in Aggressive Behavior found that individual differences in baseline testosterone concentrations were positively correlated with endorsement of political aggression and that baseline cortisol concentrations were negatively correlated with self-reported aggression among Palestinian boys living in Gaza. Here, we discuss recent evidence indicating that testosterone and cortisol interact to predict competitive, aggressive, and dominant behaviors and urge researchers collecting both hormones to perform and report analyses that formally test for such interaction effects.     

2D:4D in men is related to aggressive dominance but not to sociable dominance

It has been shown that a smaller ratio between the length of the second and fourth digit (2D:4D) is an indicator of the exposure to prenatal testosterone (T). This study measured the 2D:4D of men and assessed dominance as a personality trait to investigate indirectly if the exposure to prenatal T is related to a dominant personality later in life. Results showed that men had a more aggressive dominant personality when having a more masculine (lower) 2D:4D, while there was no relationship between sociable dominance and 2D:4D. Findings from this study indicate that it is important to distinguish different forms of dominance since other studies failed to find relationships between dominance and 2D:4D.     

Agonistic rank,aggression, social context,and testosterone in male pigtail monkeys

Two groups of pigtail monkeys were merged, a third was formed, and individual males were introduced into a group in a series of experiments examining the effects of social context upon agonistic rank, aggressive expression, and testosterone levels. In the first experiment, two heterosexual groups, containing adult males unfamiliar to the other group, were merged. The two groups fought, and the smaller group was defeated. The alpha and beta males of the defeated group were singled out for repeated attack and both showed significant drops in circulating levels of testosterone. Both males were removed from the group during the first day, but testosterone levels did not recover to baseline levels for several days. The alpha male of the victorious group, on the other hand, showed a significant rise in testosterone, which was apparent only on the day following the merger. In order to study the influence of previous social familiarity on male reception into a group, another group was formed by removing males from the victorious group and placing them in a separate enclosure. The males in the new group established a dominance hierarchy unrelated to their previous social ranks with one another. Three months later, each of the six adult males remaining in the parent group was individually introduced into the new group for one day or less. Each of the males introduced into the new group accepted a social position at the lower end of the dominance hierarchy without regard to his previous rank relationships with the host males when they were all in the parent group. Even the alpha and beta males of the parent group were relegated to low rank positions in the new group, despite having ranked over each of the host males since birth. In contrast to the aggression directed at the unfamiliar males in the first experiment, a minimum of aggression was directed to the familiar males introduced into the new group in the second experiment. Although the males introduced accepted low social ranks, it appeared that each was readily integrated into the group with a minimum of aggressive interaction during the time he was scheduled to remain in the group. There were no significant changes in circulating levels of testosterone in any of the males during the introductions of familiar males to one another.     

Adrenal mediation of intermale aggression maintained by aromatized and reduced metabolites of testosterone

Individually housed CD-1 mice were either sham castrated or castrated and treated with testosterone (T), estradiol benzoate (EB), dihydrotestosterone (DHT), a combination of EB and DHT (EB+DHT), or the injection vehicle. Following 16 days of isolation and subcutaneous injections, animals were tested repeatedly for fighting behavior in paired encounters with nonaggressive stimulus males. Results indicated that the T and EB+DHT groups fought to the same extent as the gonadally intact group. Both the EB and DHT groups fought more than the vehicle-treated group but less than the T, EB+DHT and sham castrated groups. A similar study was subsequently performed with adrenalectomized animsls. Adrenalectomy eliminated agonistic responses in animals receiving metabolites of testosterone (EB, DHT, EB+DHT) but had only slight effects in gonadally intact and T-treated, castrated mice. The results suggested that a) EB and DHT, either singly or in combination, maintain aggression through a synergism with adrenal steroids; b) the combined effects of EB and DHT reflect an additive action rather than synergistic interaction, notwithstanding the synergism with adrenal steroids; c) metabolism of testosterone to estrogen and dihydrotestosterone does not sufficiently account for the action of testosterone.     

The expression of the genes of aggressiveness in mice: The effect of androgen on aggression and sexual behavior in females

Female mice of strains selectively bred for aggressiveness or nonaggressiveness were injected with testosterone propionate (TF′) at the age of 2 days and as adults, or they were injected as adults only. Aggressive and sexual behavior was then tested with female, receptive female, and male partners before, during, and after the latter TP treatment. The females that had received both TP treatments displayed as much or as little aggression as males of the same strain, leading to the conclusion that aggressiveness genes are not linked with the male sex chromosome, even though they depend on it for their expression. The sexual behavior of the females of both strains that had received both TP treatments was altered to the male type. In the females of the aggressive strain even adult treatment alone was sufficient for this change. Aggressiveness and male sexual behavior would seem to be determined separately, although aggressiveness facilitates the display of male sexual behavior.     

Investigating digit ratio (2D:4D) in a highly male‐dominated occupation: The case of firefighters

Voracek, M., Pum, U. & Dressler, S. G. (2009). Investigating digit ratio (2D:4D) in a highly male‐dominated occupation: The case of firefighters. Scandinavian Journal of Psychology, 51, 146–156. Second‐to‐fourth digit ratio (2D:4D), a widely studied putative marker for masculinization through prenatal androgen exposure, is lower (more masculinized) in athletes than in general population controls, and athletes with lower 2D:4D have higher sporting success. Occupations differ markedly in perceived masculinity and actual maleness (sex ratios), but these givens have not yet been picked up and utilized in 2D:4D research. Accordingly, this study extended existing accounts on 2D:4D in athletes to a novel approach: 2D:4D and possible relationships to a variety of candidate variables (demographic, fertility‐related, psychological, and other) were investigated in firefighters, a highly male‐dominated occupation. Contrary to expectation, 2D:4D in firefighters (N = 134) was not lower than in local male population controls. Lower 2D:4D corresponded to lower service ranks. Replicating previous findings either unequivocally or partly, lower 2D:4D was associated with larger family size, later sibling position, left‐handedness, and higher scores in the disinhibition component of sensation seeking. Not replicating prior evidence, 2D:4D was unrelated to body‐mass index, offspring sex ratio, and sporting performance level. Novel findings included low 2D:4D in those with low relationship satisfaction and in cigarette smokers, especially among heavy smokers. Absolute finger length, a positive correlate of pubertal‐adolescent androgen levels, was also considered. This marker showed negative associations with relationship consensus and satisfaction and positive ones with perceived quality of relationship alternatives and the experience seeking component of sensation seeking. The merits of this additional marker, relative to 2D:4D, for supplementing studies of possible sex‐hormonal effects on personality and directions for future inquiry along these lines are discussed.