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Biomedical subjects

David L Rowland

Publications and source records attributed to David L Rowland.

12 recordsLinked to original sources
PubMed2006

Retarded ejaculation.

Retarded ejaculation (RE) has a relatively low prevalence (<3%), yet this condition results in considerable distress, anxiety, and lack of sexual confidence for those suffering from it. Furthermore, men with partners often experience impairment of both the sexual and nonsexual aspects of their relationships, with such negative effects compounded when procreation is a consideration. The definition of RE is ambiguous, due to the variability and paucity of data regarding normal coital ejaculatory latency. RE is influenced by both biogenic and psychogenic components, which may vary over time both between and within individuals. While specific pathophysiology can often be identified, further elucidation of the biogenic components of this dysfunction will require greater understanding of the physiological mechanisms underlying ejaculation. Yet, the most useful strategies for understanding RE will integrate rather than isolate the various biogenic and psychogenic aspects of this dysfunction. Evidence based evaluation and treatment protocols for this disorder are lower than for other sexual dysfunctions, but reports suggest better treatment efficacy when the etiology is predominantly psychogenic. As with erectile dysfunction (ED) and premature ejaculation (PE), if safe and efficacious oral pharmaceuticals are eventually developed for this condition, the treatment algorithm is likely to undergo significant alteration. Even then, however, the most effective treatments are likely to result from a combination treatment that integrates sex coaching with pharmacotherapy.

Ejaculation↗
PubMed2006

Neurobiology of sexual response in men and women.

Sexual desire, arousal, and orgasm are mediated by complex--and as yet not fully understood--interactions of the somatic and autonomic nervous systems, operating at cerebral, spinal, and peripheral levels. Furthermore, neural activity within these systems is modulated by the presence of steroid and peptide hormones, which affect male and female response differentially. At the central level, dopaminergic and serotonergic systems appear to play a significant role in various components of sexual response, although adrenergic, cholinergic, nitergic, gamma-aminobutyric acidergic, and other neuropeptide transmitter systems may contribute as well. At the peripheral level, adrenergic, cholinergic, and nitergic activation mechanisms control vascular changes that underlie vaginal lubrication and penile erection. In addition, these systems respond to descending brain and spinal influences that generate orgasmic response. Disruption of endocrine, neural, or vascular response--caused by aging, disease, surgery, or medication--has the potential to lead to sexual inadequacy. At the same time, psychological and relationship factors play an important role in healthy sexual response and may enhance or impair sexual functioning.

Arousal↗
PubMed2005

Psychophysiology of ejaculatory function and dysfunction.

Psychophysiological research has attempted to understand the relationship between subjective psychological experiences (perceptive, affective, cognitive) and physical/physiological components of sexual response, including erection and ejaculation. Such research has enabled the investigation of a number of hypotheses related to the etiology and/or cause of premature ejaculation (PE), with a number of important clarifications resulting. For example, in PE men, genital stimulation (as opposed to erotic stimulation in general) is particularly germane to dysfunctional response. Autonomic (parasympathetic and sympathetic) response patterns may be altered during the sexual response cycle. Anomalous patterns of arousal are probably involved, though not necessarily in ways that had been conceptualized originally (e.g., hyperarousal). And psychosomatic interactions between negative emotion, autonomic response, and rapid ejaculation may sustain the dysfunctional response. The results of this research dispel long-standing hypotheses regarding the etiology of PE, help refocus attention to areas of importance, and raise entirely new questions regarding possible causes of PE.

Autonomic Nervous System↗
PubMed2005

Childhood sexual abuse and early menarche: the direction of their relationship and its implications.

PURPOSE: A relationship between childhood sexual abuse (CSA) and early menarche previously has been proposed and psychobiological mechanisms for the association have been suggested. Because it has serious implications for many disciplines, we attempted to confirm that association and explore its direction, first with hypothesis 1: the negative relationship between pubertal age and CSA is based on victims' increased target gratifiability at ages of high target vulnerability, and then with hypothesis 2: CSA and circumstances surrounding it are related causally to early menarche. METHODS: African-American and multi-ethnic Caucasian women (N = 323) were interviewed at several women's clinics at Johns Hopkins Bayview Medical Center; 64 women reported premenarcheal abuse. We assessed (1) ages of CSA and menarche to determine their relationships, (2) household characteristics and their relationships with CSA, (3) variables associated with CSA, to determine the independent effect of CSA and explore potential dose response (i.e., effects of increased stress). RESULTS: CSA and menarcheal age are related negatively (p < .05). Hypothesis 1 need not be rejected totally, but with most CSA events occurring long before puberty, hypothesis 2 is supported. Theoretically, stressful CSA characteristics increase victim/nonvictim differences in menarcheal age. Stress may derive from household characteristics often related to CSA but, even controlling for them, CSA has independent effects on menarcheal age. CONCLUSIONS: Hypothesis 1 may apply when CSA occurs within 2 years premenarche but, because hypothesis 2 is supported, continuing psychobiological effects and stress engendered by CSA are underscored. Mechanisms through which they impact the developing child require further exploration, and medical and psychological attention.

Adult↗
PubMed2005

The physiological basis of human sexual arousal: neuroendocrine sexual asymmetry.

Normal sexual arousal and response suppose an integrated process involving both physiological and psychological processes. However, the current understanding of sexual arousal does not provide a coherent model that accounts for the integration of multiple physiological systems that subsequently generate a coordinated sexual response at both the spinal peripheral and cerebral central levels. Herein we suggest a model that involves both sympathetic and parasympathetic activation during sexual arousal via the two classes of gonadal hormones, androgens and oestrogens. We discuss the manner in which gonadal hormones may activate such a system, transforming pre-pubertal (non-erotic) genital stimulation to post-pubertal erogenization of stimulation and subsequent sexual arousal. Finally, we indicate that the different balance of androgens and oestrogens in men and women may generate asymmetric effects on each of the components of the autonomic nervous system, thereby explaining some of the differences in patterns of sexual arousal and the responses cycle across the sexes.

Androgens↗
PubMed2005

Recognizing the risk of erectile dysfunction in a urology clinic practice.

OBJECTIVE: To determine the utility of simple patient-reported information in signalling erectile dysfunction (ED), as a challenge for the clinical urologist or related specialist is to quickly recognize risk factors for sexual dysfunction within the time constraints of an office visit. PATIENTS AND METHODS: In a sample of men visiting a urology clinic, we determined the utility of simple patient-reported information in signalling ED. RESULTS: Information readily obtained through a patient's self-report (that typically obtained in the office setting) can be very useful in understanding and predicting the likelihood of ED. Risk factors identified largely paralleled those identified in men generally, and included age, specific urological and non-urological somatic conditions, and tobacco use. Furthermore, knowing about even moderate levels of patient-reported psychological or relationship stress was useful in assessing the risk of ED. CONCLUSION: Understanding the relationship of such risk factors to ED among men visiting a urology clinic might be particularly useful in clinical situations where the patient, for whatever reason, is reluctant to disclose an erectile problem when scheduling an appointment or even during the consultation.

Ambulatory Care↗
PubMed2005

Premature ejaculation: an observational study of men and their partners.

INTRODUCTION: Premature ejaculation (PE) is the most common male sexual dysfunction affecting men and their partners. Lack of community-based data describing this condition limits understanding of PE and its outcomes. AIM: To characterize PE in a large population of men with and without PE using patient-reported outcome (PRO) measures elicited from men and their partners. METHODS: 4-week, multicenter, observational study of males (> or =18 years) and their female partners in monogamous relationships (> or =6 months). Screening, baseline, and follow-up visits scheduled at 2-week intervals. Clinicians diagnosed PE utilizing DSM-IV-TR criteria. Intravaginal ejaculatory latency time (IELT), measured by a stopwatch held by the partner, was recorded for each sexual intercourse experience. Subject and partner independently assessed PROs: control over ejaculation and satisfaction with sexual intercourse (0 = very poor to 4 = very good), personal distress and interpersonal difficulty (0 = not at all to 4 = extremely), and severity of PE (0 = none to 3 = severe). Results. Of the total study population (N = 1,587), 207 subjects were diagnosed with PE and 1,380 were assigned to the non-PE group. Median IELT (min) was 1.8 (range, 0-41) for PE and 7.3 (range, 0-53) for non-PE subjects (P < 0.0001). More PE vs. non-PE subjects gave ratings of "very poor" or "poor" for control over ejaculation (72% vs. 5%; P < 0.0001) and satisfaction with sexual intercourse (31% vs. 1%; P < 0.0001). More subjects in the PE vs. non-PE group gave ratings of "quite a bit" or "extremely" for personal distress (64% vs. 4%; P < 0.0001) and interpersonal difficulty (31% vs. 1%; P < 0.0001). Subject and partner assessments showed similar patterns and correlated moderately (0.36-0.57). CONCLUSIONS: PE subjects reported significantly shorter IELT. Overlap in IELT distributions was observed between the PE and non-PE groups, indicating the need for additional PRO measures to characterize PE. Shorter IELT was significantly associated with reduced ejaculatory control and sexual satisfaction and increased distress and interpersonal difficulty.

Adult↗
PubMed2003

An exploration of emotional response to erotic stimulation in men with premature ejaculation: effects of treatment with clomipramine.

Emotions presumably play an important role in sexual response and dysfunction in men. Yet, few studies have investigated differences in affect between sexually dysfunctional and functional men or changes in dysfunctional men resulting from successful treatment. We compared men having premature ejaculation (PE) with sexually functional counterparts on positive and negative affects, and examined changes in their affective response to pharmacotherapeutic treatment with clomipramine, an ejaculation-retarding agent. Results indicated higher levels of specific negative affects in PE men than controls. Positive affect also differed among groups, and showed variation in response to erotic stimulation and drug treatment. When specific positive affects were analyzed, they diverged in their response to stimulus and drug manipulations. For example, all groups exhibited a decrease in arousal/sensual during clomipramine treatment, but only PE men who responded positively to pharmacological treatment exhibited significant elevation in their enjoyment of the sexual experience. The fact that alleviation of the dysfunction improved positive affect in PE men responsive to clomipramine argues for the efficacy of pharmacotherapy in promoting positive emotional experiences associated with sexual response. But the failure of negative affects to approximate the low levels typical of sexually functional men also suggests the need to consider nonpharmacological methods to ensure complete reinstatement of healthy sexual response.

Adult↗
PubMed2003

Regression strategies for analyzing the study and pharmacological treatment of sexual response: ANOVA and beyond.

As the study of human sexual response becomes increasingly complex to meet the demands of this interdisciplinary field, the need for appropriate analytical tools has grown as well. In this review, we attempt to familiarize sexologists with the wide range of applications of regression analysis to the study of human sexual response. To this end, a typical experiment in human sexual response is described, and the basic regression model for the experiment is provided. Then, depending on the specific question under investigation, the nature of the study variables, and the design of the study, a number of different regression models are suggested, with each describing a specific variation from the basic regression model. Sample outputs are included to enable comparisons across several different models. With this information, researchers may develop a better understanding of the use and flexibility of the regression model in handling the kinds of problems often encountered in the experimental study of human sexual response.

Analysis of Variance↗
PubMedDate not supplied

A review of plant-derived and herbal approaches to the treatment of sexual dysfunctions.

Despite the increasing availability of effective conventional medical treatments, plant-derived and herbal remedies continue to provide a popular alternative for men and women seeking to improve their sex life. Nevertheless, the efficacy of most herbal agents in treating sexual problems remains uncertain. Therapists and consumers alike would benefit from an increased understanding of commonly used herbal agents on the market, their purported or supported effects, and their potential side effects. To this end, we cataloged the major prosexual herbal agents currently sold in several representative health food stores. We also specify the sexual problem purportedly ameliorated by each herbal agent. Finally, we evaluate eight herbal agents commonly promoted for the treatment of sexual problems. This evaluation includes a review of the research supporting the use, efficacy, dose, adverse effects, contraindications, and possible mechanism of action of each. We conclude by commenting on the quality of current research, pointing out gaps in our knowledge, and noting the need for rigorous research and product control to adequately address questions regarding the efficacy of these agents.

Brassica↗
PubMedDate not supplied

Aging and sexual response in the laboratory in patients with erectile dysfunction.

Aging places men at increased risk for erectile problems, particularly beginning around their fifties and sixties. Using a psychophysiological assessment procedure that included visual erotic stimulation, vibrotactile stimulation, and intracavernosal injection, this study tested for possible age effects on erectile response and self-reported sexual arousal in a group of men clinically diagnosed with erectile dysfunction. We controlled for three factors of purported importance to erectile functioning: existing comorbidities, use of specific medications, and current tobacco and alcohol use. Results indicated effects from both age and tobacco use on erectile response, although these effects were not uniform across age groups. For example, age had inconsistent effects on erectile response in patients aged 50 to 90 years; tobacco use had its strongest effect on patients under 50 years of age. In general, such covariates were less able to account for variation in erectile response among patients with more-severe ED. Despite these effects, ED men even in the oldest group showed average penile circumference increases of 28 mm under ICI, an erectile response typically sufficient for vaginal intercourse.

Aged↗