Endogenous testosterone and competition: the effect of "fasting".

Salivary testosterone was measured among male college wrestlers (n = 12), some of whom fasted before their matches while others did not. Nonfasting wrestlers had increasing testosterone on the day of their match, whereas fasting wrestlers had decreasing testosterone. Apparently, fasting perturbs the normal pattern of testosterone fluctuation associated with competition. As used here, the term "fasting" does not necessarily imply 100% abstinence from nourishment.

Salivary testosterone measurements: collecting, storing, and mailing saliva samples.

Salivary testosterone measurements can be especially useful in field studies, but reliable ways of collecting and handling samples need to be established. Using cotton dental rolls to collect saliva leads to inflated testosterone scores. Sugarfree gum can be used satisfactorily to stimulate saliva among both male and female subjects. Leaving unpreserved saliva samples at room temperature for 2 weeks or mailing them unrefrigerated is satisfactory for male subjects but leads to inflated scores for female subjects.

Testosterone and pupillary response to auditory sexual stimuli.

Low-, medium-, and high-testosterone subjects listened to four 30-s recorded stimuli while a computer system continuously measured their pupil size. The stimuli dealt with sex, aggression, and two neutral topics. Subjects dilated more to sex than to the other topics. Male and female subjects responded similarly, although low-testosterone males did not dilate as long as other subjects to the sexual stimulus. Auditory stimuli avoid a brightness artifact associated with visual stimuli. Auditory stimuli can be used in a variety of pupillometry studies, including studies of ongoing conversation and social interaction.

Salivary testosterone measurements: reliability across hours, days, and weeks.

Salivary testosterone measurements would appear to be useful in behavioral research, where subjects are often reluctant to provide serum samples. The usefulness of salivary measurements depends upon their reliability, however, which was the focus of the present investigation. In four studies, 270 male and 175 female subjects collected saliva samples at times ranging from 30 min to 8 weeks apart. Subjects collected samples on at least two days, at time of awakening, midmorning, late afternoon, and late evening. Mean testosterone concentration dropped about 50% from morning to evening for both sexes, with largest drops early in the day. Mean reliability was r = .64 across two days and r = .52 across seven-eight weeks. Menstrual cycle effects were negligible. Reliability can be increased by using more than one measurement, and it is probably desirable to combine measurements taken several weeks apart. Salivary assays offer a practical way of measuring testosterone in free-ranging subjects outside the laboratory.

Male and female salivary testosterone concentrations before and after sexual activity.

Salivary testosterone concentrations were measured in male and female members of four heterosexual couples on a total of 11 evenings before and after sexual intercourse and 11 evenings on which there was no intercourse. Testosterone increased across the evening when there was intercourse and decreased when there was none. The pattern was the same for males and females. Early evening measured did not differ on the two kinds of days, suggesting that sexual activity affects testosterone more than initial testosterone affects sexual activity.

Testosterone and sex role identification in lesbian couples.

Within the lesbian community there exists a common perception that lesbians comprise two types, "butch," having more masculine characteristics, and "femme," having more feminine characteristics. The present study investigated the question of whether these perceptions are reflected in different levels of the predominantly male hormone testosterone. Salivatory testosterone levels and "butch/femme" ratings were obtained from 28 lesbian couples. Individuals within couples tended to be opposite in "butch/femme" ratings [intraclass r(26) = -0.77, p < 0.0001] but similar in testosterone levels [intraclass r(26) = 0.47, p <0.01]. Also within couples, individuals with higher "butch" ratings had significantly higher testosterone levels, although across all individuals as a whole (ignoring couple pairing) there was no correlation between testosterone and "butch/femme" ratings. The results indicate that testosterone is related to "butch/femme" characteristics, but only when regarded within the couple relationship.

Testosterone changes during vicarious experiences of winning and losing among fans at sporting events.

Basking in reflected glory, in which individuals increase their self-esteem by identifying with successful others, is usually regarded as a cognitive process that can affect behavior. It may also involve physiological processes, including changes in the production of endocrine hormones. The present research involved two studies of changes in testosterone levels among fans watching their favorite sports teams win or lose. In the first study, participants were eight male fans attending a basketball game between traditional college rivals. In the second study, participants were 21 male fans watching a televised World Cup soccer match between traditional international rivals. Participants provided saliva samples for testosterone assay before and after the contest. In both studies, mean testosterone level increased in the fans of winning teams and decreased in the fans of losing teams. These findings suggest that watching one's heroes win or lose has physiological consequences that extend beyond changes in mood and self-esteem.

Lesbian erotic role identification: behavioral, morphological, and hormonal correlates.

Lesbian scholars hotly debate the validity of "butch" and "femme" erotic roles. Although some dismiss them as social constructs, others maintain they are natural expressions of lesbian sexuality. The authors compared self-described butch and femme lesbians on gender-discriminating behavioral, morphological, and hormonal measures. Butch and femme lesbians did not differ from heterosexual women on sex role personality traits, depressive symptomology, eating disorders, or body dissatisfaction. Butch lesbians, however, recalled more childhood gender-atypical behavior and had higher waist-to-hip ratios, higher saliva testosterone levels, and less desire to give birth. These findings support the validity of butch-femme classification and suggest that butch lesbians are more male-typical compared to femme lesbians. The butch-femme classification may reflect a within-group difference caused by differential exposure to prenatal androgens.

Age and seasonal variation in serum testosterone concentration among men.

Serum testosterone concentrations from 4.462 military veterans, ages 32-44, were examined for age and seasonal variation. Testosterone concentrations were assayed from a single serum sample from each subject. All samples were drawn before breakfast, at about 8:00 a.m., from subjects recruited over a 16-month study period. Mean levels declined with age (P less than .001), from 864 ng/dl at age 32 to 602 ng/dl at age 44. Mean levels also varied with month of testing (P less than .01), with a seasonal peak in December (the seasonal peak was in November for men in their early 30s). The age effect was greater than the seasonal effect. Both effects may bear upon behaviour and should be treated as possible sources of error in studies of testosterone.

Salivary testosterone and cortisol among late adolescent male offenders.

The relationship of salivary testosterone and cortisol concentrations to personality, criminal violence, prison behavior, and parole board decisions was examined among 113 late-adolescent male offenders. Offenders high in testosterone committed more violent crimes, were judged more harshly by the parole board, and violated prison rules more often than those low in testosterone. No main effects for cortisol emerged. However, as expected, a significant interaction between testosterone and cortisol was found, in which cortisol moderated the correlation between testosterone and violence of crime. Cortisol may be a biological indicator of psychological variables (e.g., social withdrawal) that moderate the testosterone-behavior relationship. Paper and pencil measures of personality and behavior showed little relationship to hormones.

Salivary testosterone and cortisol in a delinquent and violent urban subculture.

Salivary testosterone and cortisol levels were measured in 36 U.S. college students and 29 delinquent participants of a similar age. Both groups of participants were made up of White men and women. The delinquent group, which was characterized by flamboyant dress, drug use, and violence, had significantly higher testosterone levels than the college students did, but the two groups did not differ regarding cortisol levels. Testosterone and cortisol were positively correlated in the women.

Age, testosterone, and behavior among female prison inmates.

OBJECTIVE: The objective of the study was to determine how testosterone levels, both alone and interacting with age, were associated with criminal behavior and institutional behavior among female prison inmates. METHOD: Subjects were 87 female inmates in a maximum security state prison. Criminal behavior was scored from court records. Institutional behavior was scored from prison records and interviews with staff members. Testoster-one levels were scored from radioimmunoassay of saliva samples. RESULTS: Product-moment correlations revealed first-order relationships among age, testosterone, criminal behavior, and institutional behavior. Structural equation analysis suggested a causal model in which age leads to lower testosterone, which in turn leads to less violent crime and less aggressive dominance in prison. CONCLUSION: Testosterone is related to criminal violence and aggressive dominance in prison among women, as has been reported among men. Changes in these behaviors with age are in part explained by a decline in testosterone levels.