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Penile plethysmography (PPG) is a measure of sexual interests that relies heavily on the stimuli it uses to generate valid results. Ethical considerations surrounding the use of real images in PPG have further limited the content admissible for these stimuli. To palliate this limitation, the current study aimed to combine audio and visual stimuli by incorporating computer-generated characters to create new stimuli capable of accurately classifying sex offenders with child victims, while also increasing the number of valid profiles. Three modalities (audio, visual, and audiovisual) were compared using two groups (15 sex offenders with child victims and 15 non-offenders). Both the new visual and audiovisual stimuli resulted in a 13% increase in the number of valid profiles at 2.5 mm, when compared to the standard audio stimuli. Furthermore, the new audiovisual stimuli generated a 34% increase in penile responses. All three modalities were able to discriminate between the two groups by their responses to the adult and child stimuli. Lastly, sexual interest indices for all three modalities could accurately classify participants in their appropriate groups, as demonstrated by ROC curve analysis (i.e., audio AUC = .81, 95% CI [.60, 1.00]; visual AUC = .84, 95% CI [.66, 1.00], and audiovisual AUC = .83, 95% CI [.63, 1.00]). Results suggest that computer-generated characters allow accurate discrimination of sex offenders with child victims and can be added to already validated stimuli to increase the number of valid profiles. The implications of audiovisual stimuli using computer-generated characters and their possible use in PPG evaluations are also discussed. [ABSTRACT FROM AUTHOR]

The current study examined the extent to which 1136 men were able to inhibit their sexual arousal on a phallometric assessment, when instructed to do so. Although the observed changes between the two conditions (i.e., Normal and Suppression) were small to moderate in magnitude, the change was not more than what would be expected by measurement error for most participants (e.g., 83% of pedophilic sex offenders against children did not successfully inhibit their sexual arousal in the Suppression condition). There were very few variables that were associated with the ability to suppress. Higher Pedophilia Index scores in the Suppression condition predicted a greater likelihood of sexual recidivism among sex offenders (hazard ratio = 1.17, 95% CI [1.04, 1.32]), but the ability to suppress sexual arousal was not found to predict sexual recidivism. The current study highlights the importance of accounting for measurement error and found that, when doing so, most sex offenders against children are unable to successfully inhibit their sexual arousal to children when instructed to do so, and that the ability to suppress sexual arousal is not associated with recidivism. [ABSTRACT FROM AUTHOR]

A false feedback paradigm was used to produce a discrepancy between expected and "actual" tumescence among 57 sexually dysfunctional and 58 sexually functional men randomly assigned to one of four false tumescence feedback conditions: negative (NEG), neutral (NEU), positive (POS), or no (NO) feedback. Participants predicted an erection score before viewing an erotic film and then received false tumescence feedback based on this score. Tumescence and cognitive ratings were obtained before and after the feedback. It was predicted that discrepancies would differ between dysfunctional and functional participants such that functional participants would have the ability to overcome discrepancies, whereas dysfunctional participants would not. As expected, POS decreased tumescence for dysfunctional participants and NO did not influence tumescence for either group. Unexpectedly, NEU decreased tumescence for dysfunctional participants and NEG decreased tumescence for functional participants. Despite tumescence changes, cognitive ratings generally followed the feedback that was given. These results only partially support current models of sexual dysfunction and behavioral regulation. Anxiety, self-focused attention, cognitive interference, and unexpectedness of the feedback could not account for the partial support. However, most feedback that was outside of the realm of the status quo for both functional and dysfunctional participants did decrease tumescence, despite outcome expectancies. These results suggest that both functional and dysfunctional men may be at risk for erectile failure should feedback about their performance be discrepant from what they expect. Prevention and treatment should focus on preparing men for occasional erectile failure and on helping them overcome discrepant feedback.

Sex differences in patterns of sexual arousal have been reported recently. Men's genital arousal is typically more category-specific than women's, such that men experience their greatest genital arousal to stimuli depicting their preferred sex partners whereas women experience significant genital arousal to stimuli depicting both their preferred and non-preferred sex partners. In addition, men's genital and subjective sexual arousal patterns are more concordant than women's: The correlation between genital and subjective sexual arousal is much larger in men than in women. These sex differences could be due to low response-specificity in the measurement of genital arousal in women. The most commonly used measure of female sexual arousal, vaginal photoplethysmography, has not been fully validated and may not measure sexual arousal specifically. A total of 20 men and 20 women were presented with various sexual and non-sexual emotionally laden short film clips while their genital and subjective sexual arousal were measured. Results suggest that vaginal photoplethysmography is a measure of sexual arousal exclusively. Women's genital responses were highest during sexual stimuli and absent during all non-sexual stimuli. Sex differences in degree of category-specificity and concordance were replicated: Men's genital responses were more category-specific than women's and men's genital and subjective sexual arousal were more strongly correlated than women's. The results from the current study support the continued use of vaginal photoplethysmography in investigating sex differences in patterns of sexual arousal.

Three experiments supported the idea that alcohol fosters sexual risk-taking in men and women, in part, through its effects on sexual arousal. In Experiment 1, increasing alcohol dosage (target blood alcohol levels of .00, .04, .08%) heightened men's and women's risk-taking intentions. Alcohol's effect was indirect via increased subjective sexual arousal; also, men exhibited greater risk-taking than women. In Experiment 2, an extended dosage range (target blood alcohol levels of .00, .06, .08, .10%) heightened men's risk-taking intentions. Alcohol's effect again was indirect via subjective arousal. Physiological sexual arousal, which was unaffected by alcohol, increased risk-taking via increased subjective arousal. In Experiment 3, alcohol increased women's risk-taking indirectly via subjective arousal, but alcohol-attenuated physiological arousal had no effect on risk-taking. Implications for alcohol myopia theory and prevention interventions are discussed.

The past few years have seen an increased awareness of the relevance of studying the role of sexual response, emotion, and traits such as sensation seeking and the propensity for sexual inhibition in risky sexual behavior. The current study examined the association between self-reported sexual risk taking and psychophysiological response patterns in 76 heterosexual and homosexual men. Measures included genital, electrodermal, startle eyeblink, and cardiovascular responses, and stimuli included threatening (depicting coercive sexual interactions) and nonthreatening (depicting consensual sexual interactions) sexual film excerpts. Sexual risk taking was hypothesized to be associated with decreased inhibition of sexual arousal and hyporeactive affective and autonomic responses to threatening sexual stimuli. Controlling for age and number of sexual partners in the past year, sexual risk taking (number of partners during the past 3 years with whom no condoms were used) was found to be associated with stronger genital responses and smaller eyeblink responses to both threatening and nonthreatening sexual stimuli. Correlations between genital and subjective sexual arousal were relatively low. Sexual risk taking was related to sensation seeking but not to the propensity for sexual inhibition. The findings suggest that risky sexual behavior may involve a role for psychophysiological mechanisms that are specific to sex as well as for ones that are associated with more general approach/avoidance response tendencies.

The term pedophilia denotes the erotic preference for prepubescent children. The term hebephilia has been proposed to denote the erotic preference for pubescent children (roughly, ages 11 or 12-14), but it has not become widely used. The present study sought to validate the concept of hebephilia by examining the agreement between self-reported sexual interests and objectively recorded penile responses in the laboratory. The participants were 881 men who were referred for clinical assessment because of paraphilic, criminal, or otherwise problematic sexual behavior. Within-group comparisons showed that men who verbally reported maximum sexual attraction to pubescent children had greater penile responses to depictions of pubescent children than to depictions of younger or older persons. Between-groups comparisons showed that penile responding distinguished such men from those who reported maximum attraction to prepubescent children and from those who reported maximum attraction to fully grown persons. These results indicated that hebephilia exists as a discriminable erotic age-preference. The authors recommend various ways in which the DSM might be altered to accommodate the present findings. One possibility would be to replace the diagnosis of Pedophilia with Pedohebephilia and allow the clinician to specify one of three subtypes: Sexually Attracted to Children Younger than 11 (Pedophilic Type), Sexually Attracted to Children Age 11-14 (Hebephilic Type), or Sexually Attracted to Both (Pedohebephilic Type). We further recommend that the DSM-V encourage users to record the typical age of children who most attract the patient sexually as well as the gender of children who most attract the patient sexually.

This study aimed to clarify the role of positive, negative, and ambivalent (i.e., co-occurring positive and negative) affect in predicting subjective sexual arousal, sexual desire, and genital response. A total of 26 women and 19 men observed three erotic film excerpts and a film excerpt depicting a coercive sexual encounter. Genital responses were recorded throughout the study, and participants rated their mood and subjective sexual arousal and desire following each excerpt. Results showed that positive affect was strongly and positively related to subjective sexual response. Although negative affect was generally a poor predictor of subjective sexual arousal, for women, it was positively associated with genital response in some conditions. Ambivalent affect was consistently associated with relatively high levels of subjective sexual arousal and desire. Results point to the importance of recognizing the role of ambivalent or mixed emotional states when evaluating the relationship between affect and sexual response.

Test-retest reliability and concurrent validity studies on the Adolescent Sexual Interest Card Sort (ASIC) were conducted in two samples of 38 juvenile sexual offenders, each. Of the 64 items of the ASIC, 60 were found to be significantly correlated across test administrations. Cronbach's coefficient alpha was employed to determine the internal consistency of ASIC items. Coefficients ranged from .62 to .96 across categories, with an overall alpha of .97. Client ratings of sexual interests via the Card Sort were correlated with phallometric response to similar categories of stimuli. Significant correlations were found for only 4 of the 14 categories examined, suggesting little correspondence between client report of sexual interest on the ASIC and phallometric assessment of the same. Findings are consistent with the adult sex offender literature suggesting that self-report measures are particularly vulnerable to dissimulation and often at variance with more objective measurement. Clinical and research issues pertinent to the measurement of sexual arousal and interest in juvenile sexual offenders are discussed.

Functional relationships between the penis, vagina, and cervix during copulation in the chimpanzee were studied. In 11 adult males, penile length during full erection ranged from 10.0-18.0 cm (mean +/- SD = 14.4 +/- 2.02). In 19 parous adult females examined during the early follicular phase of the cycle, or during lactation, vaginal depth (from the introitus to the os cervix) ranged from 9.8-16.5 cm (mean +/- SD = 12.6 +/- 1.69). However, when the sexual skin was maximally swollen, vaginal depth increased by up to 52% in some cases and ranged from 15.2-20.1 cm (mean +/- SD = 16.9 +/- 1.68). Under such conditions males vary in their ability to achieve maximal depth of intromission. Observations made on 6 females after natural matings revealed that in some cases males had deposited copulatory plugs in contact with the cervix, while in others plugs were lower down in the vagina. Direct observations under fluoroscopy using an artificial "penis" loaded with radio-opaque medium showed that the filiform tip can make contact with the os cervix. However, expulsion of radio-opaque medium under these conditions failed to demonstrate any immediate transfer of fluid through the cervix into the uterus. These studies indicate that, aside from its functions as a visual signal, the female chimpanzee's sexual skin swelling adds considerably to the distance males must negotiate during copulation to place spermatozoa at the cervical os. Evolution of the male's elongated, filiform penis may therefore be the result of sexual selection, to negotiate the long vagina of the female and to penetrate copulatory plugs deposited during previous copulations.

The sexual arousal profile of a subgroup of rapists with a history of low-level physical violence during their offenses was assessed. Twenty subjects participated: 10 rapists and 10 nonrapists. Stimuli consisted of audiotapes with the following five thematic contents: mutually consenting sexual activities; rape involving physical violence; rape involving humiliation; physical aggression without sexual activities; neutral. Penile responses were recorded during stimuli presentation using a mercury-in-rubber strain gauge. Data showed no differences between both groups for the rape stimuli involving physical violence. For the rape stimuli involving humiliation, however, the penile responses of the two groups differed. With those stimuli the average penile response of the rapists was higher than that of the nonrapists. Therefore, for this subgroup of rapists the association between sexual activities and humiliation presents a higher erotic value than the association between sexual activities and physical violence. Implication of these results as to the discriminant validity and classificatory accuracy of phallometry in rapists is discussed.

Sexual function, and in particular erectile capacity, declines with age in men. The present study attempted to identify possible sensory/neural and autonomic factors related to this decline. Data on self-reported sexual activity and functioning, as well as erectile response to visual erotic stimulation, were gathered from 39 healthy, sexually functional men ranging in age from 21 to 82. In addition, four parameters of putative significance to sexual functioning were measured: penile electrical and vibrotactile thresholds, pudendal somatosensory evoked potentials, penile autonomic response to ischemia, and blood testosterone. Results indicated significant age-related decreases in self-reported frequency of sexual activity and in erectile response to erotica. Furthermore, penile sensitivity, response to penile ischemia, and somatosensory evoked potentials showed age-related changes. In contrast, self-reported erectile capacity, ratings of overall sex life, and levels of testosterone did not change over age groups. These findings suggest that decreasing erectile capacity in aging men may be related to decreasing sensory/neural and autonomic functioning, but they also indicate that factors other than the frequency of and potency for sexual response are important to the overall rating of sex life.

Two experiments were conducted testing reliability of expansion chamber determined gauge element breakage ranges; 20 trials with sexually functional males provided comparative data on the gauge in actual application. Circumference of the expansion chamber and increases in penile circumference were simultaneously monitored via a mercury strain gauge. Results for both experiments indicated considerable overlap at gauge element breakpoints, and yielded an overall misdiagnosis rate of 15.5% in a young, healthy population.

To study the serial effect in phallometric experiments, several sexual stimuli (film scenes) were presented in different orders to 56 subjects in four groups. All stimuli were presented at a relatively constant basal level of penile volume after the subjects' engagement in a nonsexual cognitive task. Serial effects occurred. At the beginning of the session, the magnitude of penile response did not depend on the content of sexual stimuli, the second stimulus eliciting a higher effect than the first. The differential effect of stimuli occurred only when they were shown in the third or fourth position. Finally, it was demonstrated that the effect of the stimulus depends to some extent on the effect of the preceding stimulus.

The use of penile tumescence to categorize and assess the treatment of sex offenders has gained increasing popularity. Recent publications have expanded the use of tumescence measures for the classification of rapists. The majority of studies in the past using mainly subjects seeking treatment or admitting to difficulties in controlling rape urges have shown the technology to be a valuable asset in classification. The present investigation, however, points out the limitations of using this technology in certain populations. The responses of incarcerated rapists and incarcerated nonrape offenders were compared. Analysis of the data indicated that there were no significant differences between the responses of rapists and nonrapists and that the rape index proposed by Abel et al. (1978) did not reliably classify incarcerated rapists. This paper points out the limitations of penile tumescence assessment with certain populations and discusses possible reasons for the failure to discriminate in this investigation.

The measurement characteristics of two transducers which record penile circumference changes were compared. The subject wore two transducers simultaneously while viewing a section of an erotic film. Examination of the data revealed discrepancies in measurement between the two units, but these differences were shown to be statistically nonsignificant. Various measurement characteristics of the devices such as durability, ease of handling, and cost are discussed and recommendations are made to guide the worker in choosing a unit most suitable for clinical and research applications.

Volunteer characteristics and volunteer rates across several laboratory experiments of sexual arousal were compared. Conditions were created to assess which component of the experimental setting was responsible for low volunteer rates in experiments using genital measurement. Subjects were 324 male and 424 female undergraduate students who had volunteered for an experiment on sexuality and personality. After completing several measures of sexual experience and attitude, subjects received a written description of one of the following conditions and were asked if they wished to volunteer: sexual film, sexual film and subjective rating of arousal, sexual film and assessment through forehead temperature, sexual film and assessment with a device that was placed over the clothes and measured genital heat flow, sexual film and assessment with the heat flow device while partially undressed, or sexual film and assessment with the vaginal photoplethysmograph or penile strain gauge while partially undressed. Men were significantly more likely to volunteer than women, and volunteer rates for both men and women decreased significantly when and only when subjects were required to undress. Multivariate analyses of variance revealed that both male and female volunteers were more sexually experienced, reported more exposure to erotic materials, and worried less about their sexual performance than nonvolunteers. No differences in volunteer characteristics occurred across the increasingly intrusive conditions for women while a few differences occurred for men. The present findings suggest that researchers should be cautious about discussing the generality of findings of studies involving exposure to a sexually explicit film alone as well as of experiments that involve self-report or physiological measures of sexual arousal.

Patterns of sexual arousal were examined for eight male and eight female homosexuals. Comparisons were made in terms of physiological and subjective arousal. The results indicate that for each group there exists very distinct arousal responses, with each group showing the greatest response to same-gender homosexual activity. Results are discussed in relationship to establishing normative data for assessment and clinical function.

Copulatory behavior of wild-born individually caged laboratory stumptail monkeys (Macaca arctoides) was investigated. The monkeys were paired daily for 20 min, and altogether 536 pairings were observed. The influence of the female's menstrual cycle and social factors of male sexual activity was determined. The reactions of the other monkeys during a pairing, and masturbation behavior of the males were observed and described. It was found that when a male and female were paired daily their sexual activity remained on a rather constant and high level for months provided the pair could not see, touch, or smell each other between pairings. In these conditions the most common copulatory behavior consisted of 3-4 ejaculations. When the couple lived continuously in adjacent cages, which allowed them visual, tactual, and olfactory communication between pairings, the male ejaculated, on the average, only once during five successive pairings. Thus separation and reunion was potent in triggering sexual activity. When the couple was visually separated between sessions the male's sexual activity did not depend on the menstrual cycle of the female. The males initiated copulation and the females were always willing, except in later stages of pregnancy, to cooperate. All males masturbated to ejaculation and it was often triggered by copulation, masturbation, or any happening causing arousal in the colony. The females were never seen to masturbate outside of the heterosexual context.

The sexually arousing effects of short film scenes showing a naked actress's seductive behavior were phalloplethysmographically measured in 14 sexual deviates. These were males who had offended adult women, predominantly exhibitionists. Controls were 14 normal men. Deviates responded positively to the scenes and differentiated strong and weak seduction scenes similarly to normals. Consequently, the question arises of why deviates avoid their victim's erotic cooperation and why they do not offend their regular sexual partners. Post hoc analysis of five scenes which elicited a strikingly higher response in deviates than in normals suggested that these scenes contained reduced seductive behavior but unrestrained presentation of the genitals. This finding further encourages the laboratory study of stimulus conditions for abnormal sexual arousal which occurs during the sexual offense.

The effects of manipulating attentional focus (self-versus partner-focus) and level of partner responsiveness (high, low, and ambiguous) on sexual responding were examined with sexually functional (N = 8) men. These manipulations were embedded in six standardized 3-minute erotic audiotapes. When the partner was displaying high sexual responsiveness, partner-focus resulted in significantly higher levels of penile responding than did self-focus. Post-stimuli questionnaires indicated that, although not statistically significant, self-reported attentiveness was consistently higher under partner-focus conditions. These findings are discussed in regard to their relevance to the concept of spectatoring as discussed by Masters and Johnson (1970). A comparison to previous research that examined the same variables using videotapes is included.

The structural patterns of sexual arousal are examined for eight male and eight female heterosexuals. Comparisons are made in terms of physiological and subjective arousal. The results indicate (1) that males and females differ in both the direction and magnitude of their arousal response to a variety of erotic stimuli and (2) that there is a stronger correspondence between subjective and physiological measures of sexual arousal for males than for females. A social acceptability and/or unacceptability theory is suggested to account for similarities and differences between the male and female structural patterns of arousal. Several methods of assessing subjective arousal are included to represent those most frequently used in clinical research settings. It is demonstrated that each of the subjective measures discriminates between erotic conditions and that the information provided by each of the measures are comparable.

Instrumentation has been developed which promises to further our understanding of the relationship between cognitive and physiological factors in the sexual arousal process. Past research has examined this relationship by continuous measurement of genital response, and discrete posttest measurement of subjective arousal. The self-report or "cognitive lever" allows individuals to rate feelings of arousal continuously throughout a stimulus interval by positioning a lever device along a calibrated scale. In this way, structural patterns of physiological and cognitive response can be examined. However, since attention has been shown to be an important cognitive operation in the processing of sexual stimuli, there is concern that this subjective measuring task may confound laboratory assessment by altering genital responsivity through distractive or possibly facilitative mechanisms. In order to test the methodological limitations of the cognitive lever, 14 male and female college students were exposed to duplicate viewings of erotic videotapes while alternately using and not using the self-report device. Results indicated that lever usage was not obtrusive in females, but was in males to the point of altering physiological response. In addition, the study took advantage of the continuous, concurrent measurements and examined patterns of convergence and divergence between the two. Results of correlational analyses indicated, in line with past research, that for men greater degrees of erection result in significantly higher subjective-objective agreement. Patterns for women as a group were much less clear, with only two significant correlations appearing. Finally, the limitations of the cognitive lever were discussed.

The effects of two levels of stimulus intensity (medium and high) and two levels of stimulus variability (varied stimuli and constant stimuli) on the habituation of subjective and physiological sexual arousal were investigated in a 2 X 2 factorial design. Forty male volunteers served as subjects. It was hypothesized that, as compared to constant stimuli, varied stimuli would produce higher rates of response attenuation on indices of sexual arousal. This hypothesis was confirmed for both penile response and a subjective measure of sexual arousal. Second, it was hypothesized that stimuli of medium intensity would produce higher rates of response of attenuation on subjective and physiological indices of sexual arousal than would stimuli of high intensity. This hypothesis was partially confirmed for subjective arousal but was not confirmed for the physiological measure of sexual arousal. These results were interpreted as supporting the notions that sexual arousal to erotic stimuli decreases with repeated stimulus presentations and, since the experimental design properly controlled for physiological fatigue, that a habituation process is involved in this observed decrement. The implications of habituation for sex research are discussed.

Clinical programs for the treatment of impotence generally have been successful but without experimental verification of their individual components or factors associated with the development of impotence. Twenty-four normal males participated in an investigation comparing factors believed to inhibit or facilitate penile tumescence. The effects of demand for performance, self-monitoring of erection, and increased SNS activity, were evaluated. Subjects were exposed to sexual stimuli under these conditions and measurements of penile responses were taken. Results indicated that there were no differential effects on penile responses between demand and no-demand or between self-monitoring and no self-monitoring. Increased SNS activity appeared to facilitate loss of erection, but only after, and not during, the sexual stimulus. The clinical and theoretical implications of these findings are discussed, and suggestions are made for future research.

The purpose of the research was to determine (1) the difference in the rate of penile circumference increase per unit time between a group of young and a group of old normal males when exposed to the same erotic movie and (2) the correlation coefficient between penile shaft temperature increase and penile circumference increase. Ten males aged 19-30 years and ten males aged 48-65 years served as subjects. Each subject placed a thermistor and strain gauge on his penis and both outputs were recorded simultaneously on a two-channel recorder. The younger group responded at an erection rate 5.8 times faster than that of the older group. The correlation coefficient, based on the percent approach to oral temperature (98.6 degrees F) and the percent increase in penile circumference, was 0.75.

Androphilic, ephebophilic, and homosexual pedophilic males were compared on heterosexual interest and arousal potential. The former was measured by the subjects' retrospective reports and the latter by penile responses to pictures of females. The penile responses of the ephebophilic and homosexual pedophilic groups to pictures of physically mature females were not different from those of androphilic males. In the present study as well as in an earlier one, the ephebophilic males responded significantly more to physically mature males than to physically mature females. Homosexual pedophilic males showed little difference in responses to physically mature males and females. In retrospective reports of heterosexual interest and experience and of development of homosexual interest and activities, there were only two differences among the groups: as opposed to androphilic males, a relatively greater number of ephebophilic and homosexual pedophilic males indicated that up to age 15 or later they had felt attracted exclusively to females and that they had been seduced in childhood or early adolescence by a male. These results will have to be replicated before being accepted as reliable. As in some earlier studies, there was a weak but significant correlation of degree of "feminine gender identity" with age at onset of homosexual interest and with heterosexual interest or experience. A higher degree of feminine gender identity went together with less heterosexual interest and experience and with an earlier onset of homosexual interest and experience.

Forty-two male patients and their sexual partners were studied: 16 patients with "psychogenic" erectile failure (eight each with the primary and secondary forms), 16 premature ejaculators, and 10 patients with diabetes-related impotence. Due to the higher mean age of the diabetics, an age-matched older control group (eight healthy males and their sexual partners) and an age-matched younger control group (16 healthy males and their sexual partners) were also studied. In an experimental situation various psychophysiological parameters were evaluated. The viewing of films depicting sexual behavior produced psychophysiological reactions in all subjects. The patient groups and the controls differed on the following five parameters: amount of increase in systolic blood pressure, amount of increase in number of spontaneous fluctuations in skin resistance, erection amplitude, latency of erection, and duration of erection. In the diabetic group the three erection parameters were very depressed. In the group with primary psychogenic erectile impotence all five parameters were lower than in the controls, with the greatest difference in spontaneous fluctuations in skin resistance. The psychophysiological profile of the group of patients with secondary psychogenic erectile impotence was surprisingly similar to the profile of the diabetics, with a sharp increase in systolic blood pressure and in spontaneous fluctuations in skin resistance, but very depressed erection parameters. There were no marked differences between the controls and the premature ejaculators. There were only a few correlations between self-rated sexual arousal and psychophysiological measures of sexual stimulation and these were not very high. They were found mainly in the patient groups.

Twenty-four men were exposed to erotic material of matched content across five sessions, each separated by 24 hours or more. The stimulation within a session consisted of eight 12-minute episodes depicting heterosexual activities. Both penile circumference and subjective sexual arousal varied significantly across the segments within a session. However, neither response measure showed habituation across sessions. Participation in the study did not modify the extralaboratory sexual behaviors of subjects. These results are discussed with reference to stimulus, subject, context, and measurement variables that potentially influence the extent to which repeated exposure to erotic material affects sexual arousal within the laboratory and sexual activity outside the laboratory.

Variations of plasma LH and testosterone in relation to sleep-related penile tumescence were assessed. Plasma LH and testosterone were measured at 10-20 min intervals in five normal adult men during 2 nights of sleep. Blood samples were obtained by means of an indwelling venous catheter while sleep was monitored polygraphically and penile tumescence recorded with a penile mercury strain gauge. Tumescent episodes were recorded in all subjects during 9 of the 10 nights of the study, and the percentage of time during sleep, which was associated with tumescence, ranged from 13% to 34%. Simultaneous REM and tumescence comprised 57.7% of total tumescent time. Abrupt elevations of plasma LH and testosterone were observed during the night without a significant relationship to stages of sleep. The mean of all hormonal determinations for the five subjects did not show significant differences in plasma LH and testosterone between fully and partially tumescent episodes and nontumescent periods. Mean testosterone during REM sleep with tumescence, a state of autonomic activation involving sexual function, was consistently higher for the five subjects than during periods free from REM and tumescence.

In reports of identical twins discordant for homosexuality, the homosexual twins showed the effeminacy syndrome in childhood. This has been considered evidence that the homosexuality comes from the twin himself. The possibility that the heterosexual twin was denying homosexuality has never been excluded. A pair of identical male twins discordant for homosexuality are reported. They showed significant differences in their penile volume responses to moving pictures of male and female nudes indicative of sexual orientations consistent with their statements. The homosexual twin showed the effeminacy syndrome. Aspects of the syndrome can be induced in mammals by altering their hormonal environment during some critical period in their intrauterine development. Discordance for homosexuality in identical twins could be due to one's being exposed to a different hormonal level during such a critical period.

The belief that it is impossible for males to respond sexually when subjected to sexual molestation by women is contradicted. Previous research indicating that male sex response can occur in a variety of emotional states, including anger and terror, are corroborated. Eleven cases of male sexual molestation by females are classified and described. A post-trauma reaction occurs in which sexual function and psychological state are affected. The men were all personally interviewed. Recognition of this phenomenon should lead to increased identification of male victims as well as to better medical, psychological, and legal services for them.