Effects of a nutritional supplement on coprophagia: a study of three cases.

The cases of three individuals with profound mental retardation and long histories of coprophagia (ingestion of feces) were studied to determine if fecal material could be providing a nutrient that was unavailable from a standard institutional diet. In each case the individual was provided with a daily oral supplement of an "elemental diet," which, at twice the dose administered, would provide all the nutrients necessary for sustenance. The frequency of coprophagia was decreased in all three cases when they received the supplemental nutrients as compared to when they were maintained on a balanced institutional diet alone.

A comparison of volumetric and circumferential measures of penile erection.

Objective measurements of sexual arousal in men most commonly involve monitoring changes in penile size. Although changes in circumference are most often used, volumetric changes have been reported to be more sensitive and thus more effective. Six men volunteered to observe an erotic videotape while circumferential and volumetric changes of their penises were recorded. The two measures were significantly correlated (r = .68) but the volumetric device was more difficult to use, displayed considerably more artifacts, and was not more sensitive than a mercury-in-rubber strain gauge.

Labial and vaginal blood volume responses to visual and tactile stimuli.

Five women volunteers participated in two experimental sessions designed to evaluate the response patterns of two objective psychophysiological measure of women's sexual arousal to different methods (and intensities) of sexual stimulation (i.e., an erotic film and manual self-stimulation). A vaginal photoplethysmograph was used to measure vaginal blood volume response and a labial thermistor-clip was used to measure temperature changes of one of the minor labia. Both measures usually covaried in a highly significant manner during both types of stimulation, with the largest responses typically being evoked by the physical stimulation. The response patterns for the two measures were also similar following both methods of stimulation if the woman did not experience orgasm; both measures decreased to some extent after the stimulation ended but usually remained well above the prestimulatory baseline. Orgasm, however, affected the two genital measures differently. The vaginal blood volume measure decreased dramatically during the reported orgasm, possibly because of vaginal contractions, and then increased to at least the preorgasmic level that occurred during the stimulation. The labial measure did not change during the reported orgasm but decreased relatively rapidly soon after.

Women's sexual arousal concurrently assessed by three genital measures.

The relationship among three objective measures of genital vasocongestion in women was evaluated both during and after an erotic film using simultaneous recording of both vaginal pressure pulse and vaginal blood volume responses by means of photoplethysmography and of labial temperature change by means of a thermistor clip. During the film each of the genital measures increased for most subjects, resulting in highly significant positive correlations between measures. However, following the erotic film presentation there was considerably less direct correspondence among the three measures; although the genital reactions of most subjects subsided to some extent following the film, none of the three measures consistently returned to prestimulation levels. Periodic estimates of subjective levels of sexual arousal were significantly correlated with each of the genital measures during the erotic film but were not significantly correlated with any after the film.

Color as a variable in making an erotic film more arousing.

Eight adult male subjects participated in a counterbalanced, repeated-measures design to determine the relative efficacy of color and black-and-white visual sexual stimuli in eliciting sexual arousing, as objectively measured by a mercury-in-rubber strain gauge transducer. There were no consistent or significant differences in either the intensity of the pattern of penile responding during color and black-and-white presentations of the same film.

Analysis of the consistency of objective measures of sexual arousal in women.

Eight adult women volunteers viewed the same erotic film in two different sessions. Their resulting genital responses were recorded simultaneously by three different measures: vaginal pressure pulse, vaginal blood volume, and labial temperature change. During the erotic stimulation, the vaginal pressure pulse and labial responses always increased, and the vaginal blood volume response increased on all but two occasions. Although there was considerable intersubject variability in each genital measure, all three measures were found to have some intrasubject consistency over sessions with respect to either their response amplitudes or patterns, with labial temperature being the most consistent on both parameters. The relationship between the response patterns of the three measures during the film was also relatively consistent across sessions, as was the correspondence between subjective ratings of arousal and both vaginal pressure pulse and labial responses but not vaginal blood volume response. To overcome the problem of considerable intrasubject variability of response amplitudes, it was suggested that the inclusion in the data analysis of several parameters of response patterns, which were relatively stable over sessions, might facilitate the evaluation of a treatment.

Effects of alcohol on male sexual responding.

Sixteen adult males participated in a repeated measures design in which they served as their own control to determine the effects of various amounts of alcohol on: (1) their sexual arousal elicited by erotic motion-pictures, as measured by a penile transducer, (2) the ability to voluntarily inhibit their arousal to those same films in accordance with instructions, and (3) the ability to become voluntarily aroused in the absence of overt stimuli. The ingestion of a low (0.5 or 0.6 ml/kg) or a moderate (1.0 or 1.2 ml/kg) amount of alcohol resulted in a small, but significant, depression of mean sexual arousal, but other measures were not affected. However, the ingestion of a high (1.5 or 1.8 ml/kg) amount of alcohol resulted in every measure of evoked arousal being depressed by a comparatively large degree. The high level of alcohol also affected a very large decrease in sexual arousal when subjects were instructed to become sexually aroused in the absence of overt erotic stimuli. In contrast, none of the three amounts of alcohol caused a significant impairment in the ability of subjects to voluntarily inhibit their sexual arousal, even though most subjects experienced some deterioration in that ability after ingesting a moderate amount of alcohol. The actions of alcohol on sexual responses were not significantly correlated with its effects on a nonsexual matching task, were not related to subjective reports of how alcohol usually affects sexual behavior, and were generally not related to reported drinking history.

Myelolipoma of the adrenal gland. Angiographic findings and review of the literature.

Myelolipoma of the adrenal gland is a rare tumor. It has been surgically excised in only five cases, including the one described in this report. However, review of the literature reveals a total of one hundred thirty cases. Although more than 96 per cent of these lesions were found incidentally at autopsy and more than half could be appreciated only microscopically, it is clear that these tumors can grow sufficiently to become symptomatic, undergo hemorrhage, and require operation. The clinical angiographic and pathologic features of myelolipoma are described. Although endocrine function of this tumor has never been demonstrated, related experimental evidence of others is summarized because it suggests that complete endocrinologic evaluation of patients with suspected myelolipoma is indicated. Despite the rarity of the tumor, we believe that the radiologic and clinical features of myelolipoma that we have described may allow preoperative diagnosis in the future.

Voluntary control of eroticism.

A recent study reported that motivated human male subjects were able voluntarily to inhibit penile erection in the presence of effective erotic stimulation (Laws and Rubin, 1969). However, because this study required attendance only to the display area of erotic stimuli, there was a possibility that inhibition resulted from their subjects not attending to the content of the stimuli. The present study utilized a procedure that guaranteed subjects' attendance to the content of the erotic stimulation, i.e., a description of the behavioral content of the erotic stimulus film. Nevertheless, every subject was able to inhibit penile erection almost as effectively as when no film description was required. Furthermore, the verbal description prevented the production of competing asexual stimuli; a technique that all subjects, in both the Laws and Rubin study (1969) and the present study, reported using to inhibit penile erection when no description was required. This suggests that although concentration on asexual stimuli may be the preferred method of reducing sexual arousal to erotic stimulation, penile erection can be inhibited by other methods.

Instructional control of an autonomic sexual response.

Four of seven human male subjects developed full penile erections when exposed to erotically stimulating motion pictures. Changes in penile size were detected by a mercury strain gauge transducer and automatically recorded on a continuous paper record. When instructed to inhibit penile erection in the presence of such effective stimulus films, every subject was able to reduce his erection by at least 50%. This inhibition was apparent as long as the instructions were in effect; when the instructions were removed and the film reshown, the erection returned almost to its maximum state. This was true whether the films were presented as few as three or as many as nine times in succession. When instructed to develop an erection in the absence of a film, every subject was able to do so, each reaching a peak of about 30% of his maximum. Such erections had longer latencies to the peak produced and lower maximum levels than those elicited by a film.

The rabbit as a subject in behavioral research.

Domestic rabbits were exposed to a wide variety of variables employed in behavioral research. It was found that: (1) Although food could be used as a reinforcer, the long periods of severe deprivation required to reduce body weight made its use impractical. (2) Water was an efficient reinforcer in that it maintained high rates of behavior after 22 hr of deprivation. (3) Except that rates of responding were higher, fixed-ratio and variable-interval schedules of reinforcement produced patterns of behavior similar to those demonstrated by rats and pigeons. (4) Although the duration of the post-reinforcement pause was a function of the duration of the interval under fixed-interval schedules, scalloping, as defined as a gradually increasing rate of responding between reinforcement, was not evident. (5) When provided with the means to both turn on and turn off intracranial stimulation, the duration of the stimulation and the frequency with which it was turned on and off was a function of the intensity of the stimulation. (6) Electric shock could suppress behavior and maintain escape responding, but would maintain avoidance responding only in a few subjects.

Biting attack by rats in response to aversive shock.

Paired rats are known to behave aggressively when given painful electric shocks. The present study developed a procedure whereby individual rats given shocks might bite an inanimate target object. Unavoidable shock was delivered to the rat while it was restrained in a position close to, and facing a target object. Biting of the target was recorded automatically. Shock caused the rat to bite metal, wood, or rubber targets. Biting was most frequent immediately after shock and decreased as a direct function of time since the shock. Almost every shock produced biting and the behavior continued as long as the shocks were delivered. Biting ceased within and between sessions when shocks were discontinued. These results show how the pain-aggression relation can be studied objectively with rats.

Temporal patterns of sexual behavior in rabbits as determined by an automatic recording technique.

Sexual behavior between rabbits was automatically recorded by means of electrodes attached externally to the unrestrained animals. Current flowed only when the animals came into physical contact; the duration and amplitude of the current flow provided a means of automatic differentiation between sexual and other types of physical contact. Various temporal aspects of sexual behavior were revealed: (1) copulation was preceded by a series of thrusts that occurred at a constant frequency of 13 to 14 thrusts per sec; (2) the duration of a copulation was about 1.5 sec and could be as brief as 0.3 sec; (3) copulation was much more likely during the hours between dusk and dawn despite constant illumination; (4) copulations occurred in groups or "runs" characterized by many copulations within a few hours; (5) each run began with a high rate of copulation that often decreased over time; (6) between runs, several hours or days passed with little or no sexual activity; and (7) a run of copulations was noted at the end of every 16- to 20-day period (which corresponds to the known period of pseudopregnancy in rabbits) whether or not other runs occurred within this period.