Ethical evaluation of hypnosis research: a survey of investigators and their institutional review boards.

We surveyed hypnosis researchers and Institutional Review Boards (IRBs) with regard to the ethical evaluation of research protocols. Researchers and IRB administrators were independently surveyed within the same institutions. Both objective and free response items were used to address substantive issues such as deception and at-risk populations, as well as practical matters such as paperwork. Parallel questions allowed a point-counterpoint between researchers and IRBs. Overall, the results suggest that IRBs do not treat hypnosis research differently than other types of research. We end with recommendations for facilitating interactions between hypnosis researchers and their IRBs.

Reliability of salivary testosterone measurements: a multicenter evaluation.

The reliability of salivary testosterone assays was evaluated by nine laboratories in four countries. Each laboratory used its own RIA procedures to assay samples from a set of 100 male and 100 female subjects. Agreement among the laboratories on mean scores was within the range reported by Read (Ann N Y Acad Sci 1993; 694: 161-76). Overall agreement on individual scores, as indicated by the intraclass correlation coefficient computed within subjects across laboratories, was r = 0.87 for men and r = 0.78 for women. Mean agreement between each laboratory and the combined set of all other laboratories (via Fisher's Z-transformation) was r = 0.61 for men and r = 0.58 for women. We take these latter values to be the best estimates of the average reliability of laboratories in their ordering of individual samples.

Aggressiveness, competitiveness, and human sexual orientation.

Previous research has suggested that homosexual men are less aggressive than heterosexual men, but limitations of available studies prevent them from being conclusive. The empirical evidence is even more mixed regarding the relation of aggressiveness to female sexual orientation. We examined the relation between self-reported physical and verbal aggressiveness, interpersonal competitiveness, and sexual orientation in both men and women. The aggressiveness and competitiveness scales yielded significant sex differences, with men being more aggressive and competitive. Consistent with past findings, heterosexual men were more physically aggressive than were homosexual men; no other within-sex relationship was significant. We discuss the implications of our findings for developmental theories of sexual orientation, aggressiveness, and competitiveness.

Spatial ability, handedness, and human sexual orientation.

We investigated the relations among mental rotations and spatial perception abilities, handedness, and sexual orientation in both men and women. The present study included a relatively large sample and attempted to control statistically for important covariates such as general intelligence. Significant sex differences were obtained for mental rotations and spatial perception, but not for handedness. None of these measures was significantly related to sexual orientation within either sex.

Effects of gender and sexual orientation on evolutionarily relevant aspects of human mating psychology.

Sexual selection theory provides a powerful model for the analysis of psychological sex differences. This research examined (a) tests of several sex differences in mating psychology predicted from sexual selection theory, (b) broad developmental hypotheses about sex differences in mating psychology--through the relationship of mating psychology to sexual orientation, and (c) the structure of within-sex differences in mating psychology. Scales measuring aspects of mating psychology were administered to heterosexual and homosexual Ss of both sexes. The structure of scale intercorrelations was similar across groups. All scales yielded sex differences consistent with sexual selection theory. Homosexual Ss generally obtained scores similar to those of same-sex heterosexual Ss, though several scales were significantly related to sexual orientation. Findings constrain hypotheses concerning the origins of sex differences.

Winning, losing, mood, and testosterone.

In two experiments, male college students either won or lost $5 on a task controlled entirely by chance. In both studies, winners reported a more positive mood change than did losers and, in Experiment 2, winners reported a more positive mood change than a neutral group that did not win or lose money. After the task was completed, winners exhibited significantly higher testosterone levels than losers. Levels of cortisol, a hormone associated with stress and arousal, did not differ among the groups, suggesting that a hormone-behavior response pattern for winning and losing is specific to testosterone. These data suggest that winning can alter testosterone levels in men and that mood may mediate such changes.

Psychophysiological and endocrine responses to sexual arousal in women.

The unexplored possibility that a sexually induced endocrine response might prime further sexual arousal in women guided the current investigation. Healthy, premenopausal, heterosexual women in the follicular phase of their menstrual cycle were randomly assigned to either an experimental or a control group. The experimental group was exposed to a sexually explicit videotape, while the control group saw a nonerotic videotape. Ninety minutes later both groups saw a sexually explicit videotape. Vaginal vasocongestion and hormones (cortisol, prolactin, luteinizing hormone, testosterone) were measured continuously and subjective responses were sampled at 20-min intervals. Compared to controls, experimental subjects showed a greater amplitude and longer duration vaginal response to the second videotape. Subjective measures showed greater sexual response to the second erotic videotape compared to the first, an effect that was not mediated by the hormones measured here. Prolactin decreased significantly across the session for both groups, and several behavioral and affective responses were significantly correlated with hormonal levels. Commonalities and divergence with results of prior research point to the complexity and subtlety of endocrine interactions with sexual response as well as likely sex differences in hormone-behavioral interactions.

Qualitative and quantitative sex differences in self-reported aggressive behavioral characteristics.

Aggressive behavioral characteristics were assessed in a large group of men and women by a self-report instrument, the Aggression Inventory. Significant gender differences appeared on four factors in which men reported more physical aggression and verbal aggression than did women. Further, men had higher scores on measures of impulsiveness and lack of patience than women, while women reported being more likely to avoid confrontation. In addition to these quantitative sex differences in self-reported behavior, factor analyses indicated qualitative differences by sex, wherein most of the variance for women centered on verbal aggression, while physical aggression was the first factor for men.

Endocrine, psychological and genital response to sexual arousal in men.

The endocrine, genital, and cognitive--affective responses of sexually functional men were compared under sexually arousing and non-arousing conditions. Sexually aroused subjects showed significantly higher serum luteinizing hormone concentrations than non-aroused subjects. Testosterone concentration was correlated with higher levels of penile response, but it did not prime further sexual arousal. Cortisol and prolactin concentrations decreased in both groups, more in the non-aroused group, and appeared to both inhibit and facilitate sexual response, depending on the level of anxiety reported by the subjects. Cortisol was correlated with self-reported worry, and testosterone with relaxation. These results support a multidimensional approach to the endocrine study of sexual arousal that includes both cognitive and genital response components.

Lordotic behavior in male rats: genetic and hormonal regulation of sexual differentiation.

The male offspring of Long-Evans rats treated with the aromatization inhibitor ATD (1,4,6-androstatriene-3,17-dione) during pregnancy show high levels of lordotic behavior when treated with estrogen and progesterone in adulthood. The male offspring of Sprague-Dawley dams treated in the same way show only a slight facilitation of lordotic potential. These strain differences could reflect strain differences in gestation length and therefore differences in the timing of the sensitive period of sexual differentiation; they could reflect differences in the sensitivity to the defeminizing actions of gonadal hormones; or they could reflect differences in the sensitivity to ATD treatment. We therefore directly compared the effects of prenatal and early postnatal treatment with ATD on the potential of male Long-Evans and Sprague-Dawley rats to show lordosis when given estrogen and progesterone in adulthood. In both strains ATD treatment facilitated adult lordotic behavior. Treatment appeared to have a greater effect in the Long-Evans strain. However, control Long-Evans males were substantially more responsive to hormone treatment in adulthood than were Sprague-Dawley males. In the Long-Evans strain short-term ATD treatment (Days 20-23 of pregnancy) was as effective as long-term treatment (Days 10-23). In the Sprague-Dawley strain, ATD treatment was most effective when given prenatally and postnatally. Strain differences in hormonal sensitivity best account for the present findings.

Neuroendocrine response to estrogen and sexual orientation.

A neuroendocrine component, the positive estrogen feedback effect, thought to be related to sexual orientation and, indirectly, to sexual differentiation, was evaluated in healthy, noninstitutionalized research volunteers. Men and women with a lifelong heterosexual orientation and men with a lifelong homosexual orientation were administered an estrogen preparation known to enhance the concentration of luteinizing hormone in women but not in men. The secretory pattern of luteinizing hormone in the homosexuals in response to estrogen was intermediate between that of the heterosexual men and that of the women. Furthermore, testosterone was depressed for a significantly longer period in the homosexual men than in the heterosexual men. These findings suggest that biological markers for sexual orientation may exist.

Dihydrotestosterone stimulates mounting behavior but not lordosis in female rats.

The ability of androgens to stimulate masculine sexual behavior is thought to depend on the aromatization of such androgens to estrogens. In this scheme, reduced androgens such as dihydrotestosterone (DHT) which cannot be aromatized, are thought to exert major peripheral but little or no central nervous system influences on the display of masculine sexual behavior. Further, an early report that DHT can induce lordosis, an estrogen (E) dependent behavior, led to a notion that DHT may effect behavior through metabolic intermediates such as 5 alpha-androstane-3 beta, 17 beta-diol (ADIOL) which then binds to estrogen receptors eliciting the E-dependent lordotic response. The present study reexamined and compared the relative effectiveness of a range of DHT dosages in stimulating a characteristic masculine (mounting) and feminine (lordosis) sexual behavior. Adult ovariectomized rats were randomly assigned to either 250 micrograms or 1 mg daily injections of DHT or DHTP. Other animals received OIL injections or crystalline DHT delivered by two different lengths (20 mm or 40 mm) of Silastic capsules. Animals were tested once weekly (for 5 weeks) for mounting behavior (20 minute test). Then animals were tested thrice (once weekly) for lordosis 4 hrs after the addition of 500 micrograms Progesterone (P). Finally, all females were tested for lordotic potential to respond to 10 micrograms EB plus P. 1 mg DHT or DHTP dosages and the 40 mm-Silastic condition significantly increased mounting behavior over that of lower dosages and OIL controls. A significant correlation existed between mounting frequency and circulating level of serum DHT. Treatment with DHTP was not different than DHT in eliciting mounting behavior.(ABSTRACT TRUNCATED AT 250 WORDS)

Development of feminine sexual behavior in the rat: androgenic and temporal influences.

The contributions of prenatal and postnatal androgen exposure upon the development of sexual behavior in rats were examined by prenatal treatment of pups with an androgen antagonist (flutamide) and postnatal androgenization or castration. Male and female rats were exposed to the androgen receptor-blocker flutamide (FLU) in utero via prenatal injections to the mother on Days 10 through 22 of gestation. At birth (Day 1) males were castrated. Both males and females were injected with either 100 micrograms testosterone propionate (TP) or oil on Day 1. In adulthood all gonadectomized animals were tested for the display of feminine sexual behavior (lordosis) in response to a range of estrogen dosages. Prenatal exposure to FLU enhanced lordosis in both sexes when compared to vehicle-treated controls. Postnatal TP treatment decreased lordotic potential as expected. However, in animals given TP postnatally, those receiving prenatal flutamide had higher lordosis quotients than animals receiving vehicle treatment. These data confirm (1) that the development of feminine sexual behavior is inhibited by androgen exposure, (2) that such exposure occurs prenatally, (3) that the potential for feminine behavioral differentiation occurs prenatally as well as postnatally, and (4) that androgen acts perinatally to affect estrogen sensitivity in adulthood.

5 alpha-androstane-3 beta, 17 beta-diol binds to androgen and estrogen receptors without activating copulatory behavior in female rats.

The ability of the androgen metabolite 5 alpha-androstane-3 beta, 17 beta-diol (3 beta-A-diol) to facilitate copulatory behavior was assessed directly in adult ovariectomized rats. Neither the highest dosage of 5 mg/day for three days, nor 2 mg/day for 15 days could induce lordosis behavior in females that displayed typically high lordosis quotients with low dosages of estradiol (E). Furthermore, prolonged administration of 5 alpha-dihydrotestosterone (DHT) induced a low but significant level of male-typical mounting behavior in females, whereas 3 beta-a-diol administered for 20 days (2 mg/day) had no effect on mounting behavior. However, this reduced androgen metabolite did compete moderately well for DHT and E binding sites on androgen and estrogen receptors respectively in hypothalamic cytosol preparations. We conclude that in spite of its ability to bind to these receptors in the brain 3 beta-A-diol, a major metabolite of DHT, is totally inert with respect to sexual behavior.

Androgenic influences on feminine sexual behavior in male and female rats: defeminization blocked by prenatal antiandrogen treatment.

The prenatal influence of androgen on the development of female sexual behavior in rats was investigated. The nonsteroidal antiandrogen, flutamide (4'-nitro-3'-trifluoromethylisobutyrylanilide; SCH), was administered to pregnant female rats from days 10--22 of gestation in dosages of either 1 mg/mother-day or 5 mg/mother-day. Males and females were gonadectomized in adulthood and tested for the display of lordosis in response to estradiol benzoate (EB) alone or EB with progesterone (P). Males exposed prenatally to either the 1- or 5-mg dosage of flutamide exhibited significantly higher lordosis quotients than controls when given EB alone. The addition of P was without effect in all male groups with regard to estrogen-induced lordosis. Females exposed prenatally to flutamide had significantly higher lordosis quotients than controls when given either 0.175 or 0.25 micrograms EB daily for 3 days. Addition of P to EB treatment significantly facilitated lordosis display in control and flutamide-treated females. The increase of feminine sexual behavior in both males and females of feminine sexual behavior in both males and females resulting from prenatal antiandrogen treatment suggests that androgen, prenatally, inhibits development of female sexual behavior. This androgenic inhibition of sexual receptivity (defeminization) seems to be related to the animal's sensitivity to estrogen in adulthood.