Thesis (Ph. D.)--Lehigh University, 1997. / Includes vita. Bibliography: leaves 136-160.

Thesis (Ph. D.)--Lehigh University, 1997. / Includes vita. Bibliography: leaves 113-118.

Thesis (Ph.D.) - University of St Andrews, March 2009.

The role of brain dopamine (DA) systems in the control of anticipatory and consummatory aspects of the sexual behavior of male rats was examined in the present experiments. Experiment I explored the statistical relationship among anticipatory and consummatory measures of male sexual behavior using multiple correlations and factor analysis. Level changing, a measure of anticipatory behavioral excitement, was not related statistically to any of the consummatory measures of copulation, whereas several consummatory measures were correlated. The factor analysis revealed the existence of five factors: copulatory rate, initiation, hit rate, mount count, and anticipation; given tentative names based on the measures that loaded most heavily onto each factor. These results established that anticipatory and consummatory measures of male sexual behavior are unrelated statistically. Experiment II examined the dose-response effects of several DA receptor antagonists on anticipatory and consummatory measures of male sexual behavior. Systemic administration of the typical neuroleptics haloperidol and pimozide, and the Dl-selective antagonist SCH 23390, significantly reduced the number of level changes, increased the intromission latencies, and decreased the number of intromissions and the total number of ejaculations. The atypical neuroleptic clozapine and the D2-selective antagonist sulpiride reduced the number of level changes and significantly increased the intromission latencies, but did not affect the number of intromissions or ejaculations. In almost every case, the doses required to reduce level changing were lower than those required to increase the intromission latencies, indicating that the measure of anticipatory sexual behavior was more sensitive to disruption by DA antagonists than were consummatory measures of sexual behavior. The antiemetic agent metoclopramide decreased the number of intromissions but did not affect other anticipatory or consummatory measures of sexual behavior significantly. High doses of haloperidol, pimozide, or clozapine delayed or abolished level changing and the initiation of copulation. These results indicated that anticipatory and consummatory measures of male sexual behavior are affected differentially by DA antagonists. Experiment III provided the first evidence that haloperidol affects anticipatory and consummatory measures of male sexual behavior selectively in different brain DA terminals. Bilateral infusions of haloperidol to the nucleus accumbens reduced level changing without affecting the initiation of copulation or other consummatory measures. Bilateral infusions of haloperidol to the striatum increased the total number of ejaculations but did not affect other consummatory or anticipatory measures. Unilateral infusions of haloperidol to the medial preoptic area (MPOA) produced nearly all of the effects of systemic administration, including reduced number of level changes, increased intromission latencies, and decreased number of intromissions and ejaculations. These results indicated that DA in the nucleus accumbens and striatum are involved in the display of anticipatory sexual behavior and copulatory rate, respectively, whereas DA in the MPOA is involved in anticipatory sexual behavior, the initiation of copulation, and copulatory rate. In Experiment IV, in vivo voltammetry revealed a differential pattern of DA efflux in the nucleus accumbens and striatum, and catecholamine efflux in the MPOA, during anticipatory and consummatory phases of sexual behavior in male rats. Increased DA efflux in the nucleus accumbens and increased catecholamine efflux in the MPOA were associated with the presentation of a receptive female behind a screen and with the initiation of copulation. Efflux in both regions decreased following ejaculation but increased prior to each reinitiation of copulation. DA efflux in the striatum increased nonspecifically during copulation. Use of in vivo microdialysis confirmed the general pattern of DA efflux in the nucleus accumbens and striatum observed with voltammetry. These results were interpreted as supporting a role of DA terminals in the nucleus accumbens and MPOA, but not the striatum, in the display of anticipatory sexual behavior and in the initiation of copulation. In particular, the increased release of DA in the MPOA was viewed as sensitizing hypothalamic mechanisms involved in the control of penile erection whereas the increased release of DA in the nucleus accumbens was viewed as sensitizing motor programs necessary for the execution of anticipatory sexual responses and the initiation of mounting. / Arts, Faculty of / Psychology, Department of / Graduate

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published_or_final_version / abstract / Social Work and Administration / Doctoral / Doctor of Philosophy

Yu, Hiu Yan. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2013. / Includes bibliographical references (leaves 178-186). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts also in Chinese.

This thesis investigates the relationship between identity, behaviour and desire to examine the nature of research among homosexually active men. The hypothesis is that samples of such men necessarily reflect the definitions of sexuality and homosexuality, and their interpretation, by both the researchers themselves and their research subjects, meaning that the research process itself is marked by the subjectivity of the field of sexuality. The relationship between the observer and the observed is intrinsic to research into homosexual subjectivity and the samples obtained, therefore, represent particular kinds of sexual subjects in a particular social and sexual cultural milieu. Research in this field has given pre-eminence to behaviour over identity and desire, and, as such, has usually failed to account for these differences in sexual subjectivities. To investigate this problem, I have reviewed the relevant literature both on subjectivity and on methodological approaches to research among homosexual men, and I have appraised my own ideological and personal relationships with the subject matter. I have examined the nature of the samples of homosexual men I have obtained during my work as a researcher within the Sydney gay community and reanalysed these with regard to the particular problematic I have identified. These investigations and analyses have shown that there are numerous differences within and between the various samples of homosexual men obtained, indicating that methodological frameworks can determine the nature of the samples obtained. These differences in samples also appear to reflect differences in the ways of enacting homosexual desire among the men in the studies. However, they also parallel differences in the definitions and understandings of the target population by the researchers themselves. These differences reflect differences in definition and understanding both of homosexuality and of the population of gay men, but they also represent differing patterns in the ways of being and living ?gay?, differences in sexual subjectivity. ?Gayness? and homosexuality, as concepts in research, are both the subjective basis on which the research endeavour itself is based, as well as its representational outcome.

published_or_final_version / Social Work and Social Administration / Doctoral / Doctor of Philosophy

No description available.