RESUMEN
A methodology designed to identify potential application areas for use of networked simulations is presented. The technique, known as task and training requirements analysis methodology (TTRAM), has been independently applied to the analysis of numerous US military aircraft simulator networking requirements, and appears to effectively discriminate tasks that are prone to skill decay, that are critical to mission success, that require high levels of internal and external teamwork, and that require additional training support.
Asunto(s)
Redes de Comunicación de Computadores , Simulación por Computador , Instrucción por Computador , Análisis y Desempeño de Tareas , Aviación , Humanos , Personal MilitarRESUMEN
Electrolytic lesions were made in the medial preoptic area (MPOA) and bed nucleus of the stria terminalis (BNST) to evaluate their participation in the neural regulation of copulatory and chemoinvestigatory behaviors in male hamsters. Damage to either the MPOA or the BNST caused severe deficits in copulatory performance in a subset of the animals in each group. In the MPOA group all males displaying severe deficits had lesions which included a small central region of the caudal MPOA. In the BNST group, animals with severe copulatory deficits all had large lesions which covered most of both the medial and lateral parts of the nucleus. In contrast, MPOA and BNST lesions differentially affected chemoinvestigatory behaviors. MPOA lesions did not affect any of the males' anogenital investigation rates or attraction to female odors, even though some of these hamsters had stopped mating completely. Males with BNST lesions, on the other hand, all displayed significant reductions in their chemoinvestigatory responding even though the majority of them continued to mate normally. We suggest that the MPOA and BNST may in part regulate male sexual behavior by differentially responding to 'attractant' and 'mounting' substances within female hamster vaginal secretion.
Asunto(s)
Amígdala del Cerebelo/fisiología , Sistema Nervioso Central/fisiología , Vías Olfatorias/fisiología , Área Preóptica/fisiología , Conducta Sexual Animal/fisiología , Animales , Conducta Animal/fisiología , Copulación/fisiología , Cricetinae , Masculino , Mesocricetus , OdorantesRESUMEN
Two experiments investigated the effects of daylength on the emission of 35 kHz ultrasonic (US) calls among male hamsters. In Experiment 1, castrated males received Silastic implants subcutaneously that contained either low doses of testosterone in oil or oil alone; US calls were recorded when these males were paired with receptive females. Males exposed to eight hours of light per day (short photoperiod) called more often than males exposed to fourteen hours of light per day (long photoperiod). This was true whether or not they received testosterone. In Experiment 2, a similar testing and photoperiod exposure paradigm was used, but the subjects were gonadally intact. Among males exposed to short photoperiods, US call rates increased while endogenous testosterone levels decreased. In contrast, hamsters exposed to long photoperiods maintained stable calling rates and testosterone levels. These findings are related to recent studies concerning the neural mechanisms that regulate ultrasonic vocalizations and to the possible role of photoperiod in modulating conspecific aggression.
Asunto(s)
Luz , Periodicidad , Conducta Sexual Animal/fisiología , Testosterona/fisiología , Vocalización Animal/fisiología , Animales , Cricetinae , Hipotálamo Medio/fisiología , Masculino , Mesocricetus , Área Preóptica/fisiología , Factores de Tiempo , UltrasonidoRESUMEN
Male hamsters were tested for copulatory behavior (CB) with receptive females, for investigatory responses to the females' ano-genital region (A/G), and for attraction to female hamster vaginal secretion (FHVS). After castration, the males received Silastic capsules containing one of two doses of testosterone (T), 5 alpha-dihydrotestosterone (DHT), estradiol (E2) or DHT + E2, and the maintenance of their copulatory and chemoinvestigatory responsiveness was assessed during weekly tests for the next month. The major findings were: (1) T thresholds for the maintenance of CB were lower than they were for the maintenance of A/G behavior and FHVS attraction; (2) DHT + E2 or DHT alone were more effective in maintaining A/G and FHVS attraction than was E2 alone; (3) DHT + E2 or DHT alone maintained ejaculatory behavior in some animals but E2 did not; (4) the posttreatment maintenance of normal ejaculation latencies and intromissions to ejaculation shown by intact and T-treated males was not demonstrated by males receiving DHT or DHT + E2. These results are consistent with the hypothesis that copulatory and chemoinvestigatory behaviors may be subserved by distinct neuroendocrine mechanisms in male hamsters.
Asunto(s)
Conducta Sexual Animal/efectos de los fármacos , Testosterona/farmacología , Animales , Copulación/efectos de los fármacos , Cricetinae , Dihidrotestosterona/farmacología , Interacciones Farmacológicas , Estradiol/farmacología , Hipotálamo/efectos de los fármacos , Masculino , Mesocricetus , OrquiectomíaRESUMEN
In male hamsters, chemosensory responsiveness to sexually relevant female odors is facilitated by testosterone (T). Some evidence suggests that this is not a sexually dimorphic response in that adult females can respond similarly to males following administration of T. This was evaluated and additionally, the hypothesis that facilitation of chemosensory responsiveness by T might be mediated by the conversion of T to aromatized or 5 alpha-reduced metabolites was tested. In 2-min tests, we measured the time adult males or females investigated female hamster vaginal secretion (FHVS). These animals were gonadectomized and administered T, 5 alpha-dihydrotestosterone (DHT), estradiol (E2), or a combination of DHT and E2, by subcutaneous implantation of Silastic capsules. FHVS tests were conducted either 2 and 4 weeks, or 4 and 6 weeks subsequent to gonadectomy and hormone treatment. Comparisons among groups receiving different hormone doses indicated that (1) males and females are not equally responsive to the attractant properties of FHVS, and that (2) neither DHT, E2, nor their combination, can duplicate the effects of T in facilitating responsiveness to FHVS in either sex. The copulatory behavior of males under the hormone conditions described was also tested and it was found that variations in the rate at which the test males sniffed or licked the receptive female's anogenital region correlated with variations in measures of the males' sexual performance.