Salivary testosterone and self-report aggressive and pro-social personality characteristics in men and women

Measures of salivary testosterone and the personality dimensions of aggression and pro-social behavior were obtained in 306 (155 male and 151 female) university students. Each participant provided two samples of saliva and completed ten self-report personality scales from multiple inventories. A factor analysis of the personality scales produced two factors, an aggression factor and a pro-social behavior factor. Men averaged five times the amount of salivary testosterone as women (99 pg/ml vs. 18.5 pg/ml) and rated themselves as more aggressive and less nurturant. Within each sex, testosterone was positively correlated with aggression and negatively correlated with pro-social personality. Structural equation modelling analyses suggested that a direct effect model best described the relationship between salivary testosterone and the latent personality dimensions of aggression and pro-social behavior. © 1996 Wiley-Liss, Inc.     

Testosterone intake and aggressiveness: Real effect or anticipation?

In a double-blind experiment, human males (n = 27) were given either testosterone (40 mg/day), placebo, or no treatment, over a one week period. Subjective and observer assessed mood estimations were conducted before and after treatment. Testosterone levels in saliva were measured with radioimmunoassay. The results revealed a significant placebo effect [c. f. Medicine and Science in Sports 4: 124–126]: After treatment, the placebo group scored higher than both the testosterone and the control group on self-estimated anger, irritation, impulsivity, and frustration. Observer-estimated mood yielded similar results. The lack of a placebo effect in the testosterone group is intriguing, and may be due to secondary effects caused by suppression of the body's own testosterone production, since recorded non-protein bound testosterone did not significantly rise due to treatment. The resultss suggest that androgen usage causes expectations, rather than an actual increase of aggressiveness. © 1994 Wiley-Liss, Inc.     

Anger and aggression in women: Influence of sports choice and testosterone administration

We report on two studies of anger and aggression in women. One study concerns an experimental study of anger induction in aggressive and non-aggressive sportswomen. It was found that sports choice in itself, contrary to expectation, does not predict anger arousal and aggressive behavior in the laboratory. However, at an individual level the anger proneness of the subject, as measured by a questionnaire we developed, was related to the intensity of aggressive behavior and subjectively reported anger. The second study concerns the activating effects of androgens on aggression and anger proneness. In a group of 22 female-to-male transsexuals, a battery of anger proneness and aggression questionnaires was administered twice: shortly before and 3 months after the start of androgen treatment. Administration of androgens was clearly associated with an increaese in anger proneness, although there were no changes in several aspects of overt aggressive behavior. © 1994 Wiley-Liss, Inc.     

Effect of chronic ethanol administration on intermale aggression in rats

An experiment was performed to study the effect of chronic ethanol administration on intermale aggression in rats using a 24-hour resident-intruder test. During the resident-intruder test residents displayed virtually all of the agonistic behaviors, and intruders displayed virtually all of the defensive behaviors. Intruders treated with ethanol displayed more defensive behavior and elicited more agonistic behavior than control intruders. Twenty minutes into the resident-intruder test intruders showed the greatest increase in corticosterone (338% vs. 129%), while residents showed the greatest increase in testosterone (103% vs. 18%). On the 2nd day of the resident-intruder test intruders lost more weight than residents (21.5 g vs. 10.2 g). Plasma corticosterone levels remained elevated for the intruders, and in particular for those intruders displaying defensive behaviors regardless of the resident's behavior. Plasma testosterone levels remained elevated for those residents that were paired with intruders that displayed defensive behaviors regardless of the resident's behavior. The frequency and severity of biting attacks by ethanol residents was significantly greater than that of control residents. In addition, the locus of biting attack shifted from the upper back of intruders paired with control residents to the flanks, tail, lower feet, and ventral surface on intruders paired with ethanol residents.     

Variation in aggressive behavior and anatomo-physiological correlates generated by crowding without physical contact in the house mouse

Behavioral, physiological (i.e., endocrine), and anatomical consequences of crowding in mice were studied in a situation where animals were in auditory, visual, olfactory, and tactile contact but restrained from full physical interactions, to prevent overt aggression. Males that cohabited with females undisturbed by neighboring conspecifics showed greater propensity to attack same-sex intruders and had higher plasma testosterone levels than did their “crowded” counterparts, that is, males cohabiting with females and housed adjacent to other male/female pairs. In this respect, the latter animals resembled submissive males. However, a significant increase in weight of androgen-dependent target organs (i.e., seminal vesicles and preputial glands) was found in crowded males. These data indicate that despite the observed inhibition of social aggression these males are not physiologically comparable (homologous) to male mice that experienced defeat and the stress of submission during fighting. The intriguing possibility that different conversion pathway of testosterone are accelerated, as a result of social communication, in males living in these two environments and the behavioral implications of these possibilities are discussed. Finally, the parental behavior of crowded animals, although not freely interacting with each other, was disrupted, causing a marked decrease in reproductive success. In this situation a high incidence of infanticide of their offspring by both parents was observed, whereas this behavior was virtually absent in non-crowded male/female pairs.     

Sex and ear differences in spontaneous and click-evoked otoacoustic emissions in young adults

Effects of sex and handedness on the production of spontaneous and click-evoked otoacoustic emissions (OAEs) were explored in a non-hearing impaired population (ages 17-25 years). A sex difference in OAEs, either produced spontaneously (spontaneous OAEs or SOAEs) or in response to auditory stimuli (click-evoked OAEs or CEOAEs) has been reported in infants and children, but healthy young adults seldom have been the target of study. In the current data, a robust sexual dimorphism was confirmed, with women producing more numerous and stronger SOAEs, and CEOAEs with greater response amplitude compared to men. A right-ear advantage was found for the number of SOAEs produced and, in women, for SOAE power. Although handedness did not moderate the ear asymmetry in production, exploratory analyses revealed that departures from strong right hand preference were associated in the present sample with reduced numbers or strengths of OAEs. The results are discussed with respect to differential exposure to androgens during prenatal development.     

Immobility reaction at birth in newborn infant

Objective

To describe an immobility reaction (IR) that was not previously reported at or immediately after birth in human newborns.

Method

We analyzed 31 videos of normal term vaginal deliveries recorded from Time 0 of birth defined as the as the moment that lies between the birth of the thorax and the pelvis of the infant. We searched for perinatal factors associated with newborn's IR.

Results

IR at birth was observed in 8 of the 31 newborns. The main features of their behavior were immobilization, frozen face, shallow breathing and bradycardia. One of the 8 newborns had sudden collapse 2 h after birth. We found significant relationships between maternal prenatal stress (PS) and IR (p = .037), and a close to significant one between infants’ lividness at Time 0 and IR (p = .053). The first breath of the 31 newborns occurred before and was not associated with the first cry (p < .001).

Discussion

The main features of IR at birth are similar to those of the universal most severe response to severe stress or danger. The relationship with PS suggests that children who had IR at birth might be at risk for similar disorders as those associated with PS. Sudden neonatal collapse of one of the IR newborns needs further research to determine if they are at risk for sudden infant death syndrome.

Conclusion

This first report of an IR reaction at birth in human infants could open up new paths for improving early neonatal care. Further research is needed for maternal PS, stress hormones, umbilical cord blood pH measurements in IR newborns. The challenge of education and support for parents of IR newborns is outlined.     

Individual Differences in Antisocial Punishment in Public Goods Situations: The Interplay of Cortisol with Testosterone and Dominance

This research investigates which endocrinological and psychological factors are associated with individuals' tendency to engage in destructive antisocial punishment, that is, to costly punish cooperative individuals in public goods situations. In this work, we focus on the interplay of endogenous cortisol with testosterone and dominance. We applied the dual‐hormone hypothesis according to which testosterone is positively associated with destructive and dominant behavior but only in individuals with low levels of cortisol. Study 1 shows that individuals are more likely to engage in destructive antisocial punishment in a public goods game with the option to punish when their testosterone level is high, given that their level of cortisol is low, which bolsters the dual‐hormone hypothesis. In contrast, no significant interaction effect of testosterone and cortisol emerges for the punishment of uncooperative free‐riders (altruistic punishment). In a second study, we build on these findings and document that self‐reported dominance is only positively associated with antisocial punishment (but not with altruistic punishment) when cortisol is low. In sum, the results indicate the importance of taking endocrinological and psychological factors (and their interactions) into account in order to reach a comprehensive understanding of individuals' behavior in social dilemma situations. Copyright © 2013 John Wiley & Sons, Ltd.     

Effectiveness of testosterone therapy for masculinizing voice in transgender patients: A meta-analytic review

Background: Testosterone therapy is the predominant treatment for voice masculinization in transgender patients. Although lowering of voice fundamental frequency (f₀) occurs with testosterone therapy, evidence suggests voice and gender identity may not fully align—i.e., voice-gender congruence may not be achieved—with its use.

Aim: This meta-analytic review evaluates the effectiveness of testosterone therapy to masculinize voice in transgender patients.

Methods: Multiple electronic databases were queried (inclusion dates: from database inception up to October 27, 2017) to identify original research on voice masculinization using testosterone therapy. Nineteen articles were included in this meta-analytic review, which followed PRISMA guidelines. In addition to qualitative analyses, random effects proportion meta-analyses were performed on data related to f₀, voice-gender congruence, voice problems, and satisfaction with voice.

Results: A meta-analysis on f₀ data showed after 1 year of testosterone therapy a combined estimate of 21% of participants (95% confidence interval [CI]: 5%–43%; I²: 59.9%) did not achieve cisgender male normative frequencies (f₀ ≤ 131 Hz). Meta-analyses on incomplete voice-gender congruence and voice problems indicated combined estimates of 21% (95% CI: 10%–34%; I²: 0.0%) and 46% (95% CI: 14%–79%; I²: 90.2%), respectively. Regarding incomplete satisfaction with voice, a meta-analysis showed a combined estimate of 16% (95% CI: 7%–28%; I²: 0.0%).

Discussion: We found that not all transgender patients using testosterone therapy to masculinize voice should expect f₀ lowering to cisgender male normative frequencies after 1 year. The vocal transition may involve voice problems for many patients, and some might not achieve voice-gender congruence without additional, voice-specific intervention. Given these findings, a voice evaluation should occur prior to initiating testosterone therapy and involve counseling on expectations for voice. Transgender patients who pursue voice masculinization may need management from laryngology and speech and language therapy to improve voice-gender congruence, mitigate voice problems, and increase satisfaction with voice.