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221.
Courtship learning in Drosophila melanogaster: Diverse plasticity of a reproductive behavior
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Mechanisms for identifying appropriate mating partners are critical for species propagation. In many species, the male uses multiple sensory modalities to search for females and to subsequently determine if they are fit and receptive. Males can also use the information they acquire in this process to change their courtship behavior and reduce courtship of classes of targets that are inappropriate or unreceptive. In Drosophila, courtship plasticity, in the form of both nonassociative and associative learning, has been documented—the type of learning depending on the nature of the trainer. The conditions in which the male is presented with the training target can profoundly alter the cues that he finds salient and the longevity of the memory that he forms. With the exception of habituation and sensitization, these types of plasticity have an operant component in that the male must be courting to respond to the behavior-altering cues. Courtship plasticity is therefore a complex and rich range of behaviors rather than a single entity. Our understanding of these plastic behaviors has been enhanced by recent advances in our understanding of the circuitry underlying courtship itself and the identification of chemical cues that drive and modify the behavior. Courtship learning is providing a window into how animals can use a variety of sensory inputs to modulate a decision making process at many levels.When confronted with a potential mate, Drosophila melanogaster males perform a stereotyped courtship ritual. This behavior serves at least two obvious functions for the male. The first is to prime conspecific females for copulation. During courtship, the female is assessing the male''s suitability, and if the song he sings (Burnet et al. 1971; von Schilcher 1976a) and pheromones he emits (Grillet et al. 2006; Kurtovic et al. 2007) are correct for her species and of sufficient quality, her willingness to copulate is increased. She will slow her locomotion, present her abdomen to the male, and then spread her wings and genital plates to allow him to mount (Lasbleiz et al. 2006). A second function of courtship is that it allows a male to accumulate information about the target courtship object to assess its suitability and receptiveness. The male uses auditory, mechanosensory, visual, and chemosensory signals from the target to make this assessment (for review, see Villella and Hall 2008; Ejima and Griffith 2009).Since D. melanogaster males will avidly initiate courtship of a wide variety of inappropriate and/or unreceptive targets, including immature males, sexually immature virgin females, mated females, and heterospecific females, the information obtained during courtship is critical to deciding whether to increase the intensity of his effort or terminate pursuit of the target. In the last several years, courtship has become a favored model for those researchers interested in how the nervous system specifies “innate” behaviors. While it is true that a male does not have to be instructed to produce adequate courtship (Hall 1994; Clyne and Miesenbock 2008), this apparently stereotyped behavior is far from static: It can be modified in a dizzying number of ways by experience. In this paper, we will discuss how information gathered during courtship can allow males to learn about specific types of courtship objects and broadly modify future behavioral responses to a particular class of target. 相似文献
222.
An abundance of literature exists concerning the marital relationship. While most research focuses on divorce and the social consequences of this phenomenon, more recently social scientists have focused on the marriages that remain intact. The purpose of this study was to gain insight into what factors make marriages last. This study used qualitative methodology to gain further insight into long-term marriages. Interviews were conducted with 15 heterosexual couples who had been married for at least 35 years and who identified their marriage as happy. Results indicate that for each couple the factors contributing to the longevity of their happy marriage were numerous and unique. While the most commonly mentioned factors included friendship, love, and similar backgrounds or interests, a wide range of responses were elicited. 相似文献
223.
Alan M. Leslie 《Current directions in psychological science》2001,10(4):124-127
The fundamental nature of learning is a central problem in psychology. Traditionally, psychologists have assumed that learning must involve the formation of associations. Early last century, the pioneering work of Pavlov on conditioned learning in animals seemed to put this assumption beyond doubt. More recently, many psychologists came to believe that a different kind of process must underlie complex learning, such as language learning in humans, and that this process must be described as computational rather than associative. Whether complex human learning is associative or computational continues to be a subject of intense research. The articles in this Special Section turn this debate on its head by asking whether simple animal learning is associative or computational. Surprisingly, the question is still very much open, and excitingly, it appears quite tractable. 相似文献
224.
The Psychological Record - Treatment with 8.0 mg/kg fluprazine hydrochloride had no effect on the acquisition of a step-down avoidance response but retarded its extinction. The drug also impaired... 相似文献
225.
Dissociations of writing and praxis: Two cases in point 总被引:2,自引:0,他引:2
H. Branch Coslett Leslie J. Gonzalez Rothi Edward Valenstein Kenneth M. Heilman 《Brain and language》1986,28(2):357-369
For normal writing it is essential that both motoric and linguistic competence be present; disruption of one or the other of these faculties may result in qualitatively different types of agraphia. Two right-handed patients became agraphic after left hemisphere lesions; pure apraxic agraphia in the absence of limb apraxia developed in one patient and pure linguistic agraphia in association with severe ideomotor limb apraxia in the other. The performance of these patients not only serves to illustrate the dissociation between the motoric and linguistic faculties that underlie writing but also confirms that ideomotor limb apraxia and apraxic agraphia are distinct and dissociable entities. 相似文献
226.
The present study examined factors with the potential to affect sensitivity of the tail flick measure of thermal nociception in rats. The length of the habituation period before testing began, the apparatus ramp speed, and the light:dark cycle were manipulated in a within-subjects design to determine which factors minimize the variability between baseline trials. Factors had little effect on mean baseline latencies, but standard deviations were affected. Lower variability occurred after 0- and 15-min habituation periods than after 60-min periods, after a constant light cycle than after a light:dark cycle, and after a higher temperature thermal apparatus than after a lower temperature. Although statistically significant, these effects were modest in size. These results may be of some use to those comparing studies that used very different parameters and to those designing studies and trying to optimize conditions. 相似文献
227.
The degree to which infant and maternal characteristics were related to maternal psychological distress and play competence was examined in 40 mother preterm and full-term dyads. Measures of maternal psychological distress, self-efficacy, infant temperament, and mother-infant interaction in a play situation, were obtained at 4 months corrected for prematurity. Results revealed that maternal self-efficacy was the strongest correlate of maternal psychological distress but was not related to maternal play competence. Interaction effects for unadaptable temperament and infant behavioral involvement were found in the regressions predicting both maternal psychological distress and maternal play competence. Mothers of more adaptable and less behaviorally involved infants reported greater psychological distress and exhibited greater play competence than mothers of more adaptable and involved infants. The results suggest that a lack of concordance between mothers' perceptions of their infants' behavior and actual behavioral experiences adversely affects mothers' affect and the quality of their play interactions. 相似文献
228.
Thirty-one first-time attenders for marriage guidance counselling were given a non-schedule standardised interview and a client questionnaire. The main aim was to identify the counselling and counsellor characteristics which clients considered would be most helpful in dealing with their problems. Traditional counselling skills such as the ability to be warm, supportive, understanding and a good listener were seen to be important by most clients. However, the vast majority of clients indicated that it would be helpful to receive the counsellor's opinion about their marriage, their personal problems and marriage in general: this is incompatible with a non-directive approach to counselling. Whilst clients may not know best how they should be helped, counsellors who fail to address their preconceptions risk mutual disappointment and premature termination of counselling. 相似文献
229.
Sex and age differences in the quality and intensity of children's emotional attributions to affect-laden stories were explored. Seventy-two 7-, 9-, and 11-year-old children, with equal numbers of boys and girls of each age, were individually told 10 affect-laden stories. After each story, children were asked to indicate how they would feel as the story protagonist by pointing to angry, sad, happy, and scared faces, each of which had three degrees of intensity. The results revealed that boys attributed anger to themselves more frequently than did girls; girls attributed sadness and fear to themselves more frequently than did boys. Boys' first responses to the stories were more intensely angry and more intensely happy than were girls' first responses; and the intensity of both boys' and girls' emotional attributions decreased with age.This research was funded by a grant from the Graduate School of Boston University, #GRS-661-PS. The author expresses appreciation to the faculty and students of the Bartlett School, Lowell, Massachusetts, and to the Lowell-Lesley College Teacher Corps Project, especially to Allan Alson, John Cronin, and Edna Robinson. The author would also like to thank Shirley Brody, Emily Flynn, Benjamin Gozun, and Richard Simon for their help in various phases of this project. 相似文献
230.