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241.
Rats submitted to a chronic variable stress regime exhibited more inactivity during inescapable shock as compared with unstressed rats. Besides, chronic treatments with desipramine, imipramine, clomipramine, or phenelzine reduce the amount of inactivity exhibited during this aversive experience. Furthermore, the combination of both chronic treatments--stress and antidepressants--resulted in a potentiation of the antidepressant effect alone. This higher antidepressant efficacy may result from the interaction of the neural mechanisms triggered by chronic stress exposure and antidepressant drugs. 相似文献
242.
Norway rat fetuses (Rattus norvegicus) exhibit a stereotypic behavioral response when the umbilical cord is experimentally compressed with a vascular clamp. In this study, the development of the fetal behavioral response to cord compression was compared in altricial and precocial rodents, which differ markedly in neural and motor maturity at the time of birth. Both altricial and precocial species showed some form of behavioral response to umbilical cord compression. Fetuses of two altricial species, Norway rats and Mongolian gerbils (Meriones unguiculatus), expressed hyperactivity in response to cord compression throughout the last third of gestation. In contrast, precocial cotton rats (Sigmodon hispidus) and spiny mice (Acomys cahirinus) did not respond to cord compression until relatively late in gestation. Thus, altricial and precocial species do not express the cord compression response during comparable periods of neural development: precocial species are much more mature at the earliest expression of this behavior than altricial species. These findings are consistent with the interpretation that the cord compression response is a behavioral adaptation that can promote survival of the fetus in utero. 相似文献
243.
W Epstein T Babler S Bownds 《Journal of experimental psychology. Human perception and performance》1992,18(2):503-511
The hypothesis that representation of projective shape is preattentive whereas representation of objective shape in three-dimensional space requires allocation of attention was tested in 2 visual search and 2 precuing experiments. In the visual search experiments, the slope for projective shape search was expected to approach 0 and that for objective shape search was expected to be a positive monotonic function of set size. In the precuing experiments, the effects of precuing were expected to be largely limited to the task requiring representation of objective shape. The overall pattern of results conformed to expectations. The findings are interpreted in the context of a model of shape-at-a-slant processing set out by Epstein and Lovitts (1985) and Epstein and Babler (1989, 1990). 相似文献
244.
According to a conditioning analysis of the orientation-contingent color aftereffect (McCollough effect, ME), orientation stimulus (grids) become associated with color. Contrary to this interpretation are reports that simple forms cannot be used to elicit illusory color and that the ME is not degraded by decreasing the grid-color correlation. The present results indicate: (a) Form stimuli can contingently elicit color aftereffects; (b) even a non-patterned stimulus--the lightness of a frame surrounding a colored area--can contingently elicit color aftereffects; (c) this frame lightness-contingent aftereffect, like the ME, persists for at least 24 hr; and (d) the frame lightness-contingent aftereffect can be used to demonstrate that correlational manipulations affect the ME, as they affect other types of conditional responses. 相似文献
245.
J E Cutting K Springer P A Braren S H Johnson 《Journal of experimental psychology. General》1992,121(1):41-72
People find their way through cluttered environments with ease and without injury. How do they do it? Two approaches to wayfinding are considered: Differential motion parallax (DMP) is a retinal motion invariant of near and far objects moving against fixation; the information in optical flow (IOF) is a radial pattern of vectors, relying on decomposition of retinal flow. Evidence is presented that DMP guides wayfinding during natural gait, accounting for errors as well as correct responses. Evidence against IOF is also presented, and a space-time aliasing artifact that can contaminate IOF displays is explored. Finally, DMP and IOF are separated, showing they can yield different results in different environments. Thus, it is concluded that (a) DMP and IOF are different, (b) DMP and not IOF is used for wayfinding, (c) moving observers do not usually decompose retinal flow, and (d) optical flow may be a mathematical fiction with no psychological reality. 相似文献
246.
S L Young M S Fanselow 《Journal of experimental psychology. Animal behavior processes》1992,18(4):400-413
Conditional stimuli (CS) associated with painful unconditional stimuli (US) produce a naloxone-reversible analgesia. The analgesia serves as a negative-feedback regulation of fear conditioning that can account for the impact of US intensity and CS predictiveness on Pavlovian fear conditioning. In Experiment 1 training under naloxone produced learning curves that approached the same high asymptote despite US intensity. Shifting drug treatment during acquisition had effects that paralleled US intensity shifts. In Experiment 3 naloxone reversed Hall-Pearce (1979) negative transfer using a contextual CS, indicating that conditional analgesia acquired during the CS-weak-footshock phase retards acquisition in the CS-strong-footshock phase. Experiment 5 used a tone CS in both a latent-inhibition and a negative-transfer procedure. Only negative transfer was blocked by naloxone. Therefore, negative transfer but not latent inhibition is mediated by a reduction of US processing. 相似文献
247.
The global threat of AIDS requires massive public educational campaigns that employ social and behavioral sciences such as psychology, sociology, and anthropology because sexual behavior possesses a social dimension. Research is concerned with what stimulates behavioral change, what are the prerequisites of learned behavior, and what enables personal control over the environment and future. Educational programs designing strategies for AIDS prevention require social and behavioral science content and input. Interdisciplinary provides general principles with psychological, social, and cultural aspects of human behavior. Without knowledge about psychological processes (thinking, perception, speech, aspects of personality, and interactive behavior) and social processes (economic conditions, social networks, and resources) which are implicated in health problems and also in AIDS, these educational programs cannot produce credible results. These programs and their subsequent implementation require their application in practice in a systemic and consistent fashion. Evaluations are also needed to make sure that the applied processes for behavioral change conform to methodological criteria that ensure their effectiveness. These types of studies are more complex than pure AIDS research which is aimed at finding a cure. 相似文献
248.
Laird S. Cermak Mieke Verfaellie Marie Sweeney Larry L. Jacoby 《Brain and cognition》1992,20(2):367-377
To examine the relative contribution of fluency and recollection to the word completion performance of amnesics, we administered a task in which patients were told specifically not to utilize previously presented words during stem completion (an Exclusion condition). This condition was contrasted with a standard word completion task in which patients were encouraged simply to complete the stem with the first word that came to mind (an Inclusion condition). Since the exclusion condition necessitated controlled respecification of the initial presentation, it was hypothesized that amnesics would be less able than controls to exclude study list items. Consistent with this hypothesis, the results indicated that the amnesics' performance, unlike that of the alcoholic controls, did not significantly differ as a function of task condition. To examine whether amnesics' conscious recollection could be enhanced, Experiment 2 presented the study list five times. The amnesics now were able to exclude a significant number of items from the study list; however, they still did so considerably less frequently than alcoholic controls. For the alcoholic controls, increasing the number of study trials had little additional effect on their exclusion performance, but it significantly enhanced their inclusion performance. Taken together, these findings suggest that for control subjects, word completion performance is likely mediated by a combination of fluency and recollection, while for amnesic patients, performance is almost exclusively based on the fluency with which an item comes to mind. 相似文献
249.
The current study investigates sources of between-subjects variation in asymmetry scores on visual half-field and dichotic listening tasks. For each of these presentation modalities, subjects were given multiple laterality tasks. Results indicate that about 50% of the between-subjects variations in asymmetry scores in each modality is attributable to individual differences in perceptual asymmetries that are not stimulus-specific, referred to as "characteristic perceptual asymmetries" in this paper. In addition, the question of whether individual differences in characteristic perceptual asymmetries are modality specific, modality general, or both was investigated by entering subjects' asymmetry scores from visual half-field and dichotic listening tasks into a principal component analysis. The results of this analysis indicate that there are both modality specific and modality general influences on subjects' characteristic perceptual asymmetries. 相似文献
250.
Hardiness: a review of theory and research. 总被引:7,自引:0,他引:7
S C Funk 《Health psychology》1992,11(5):335-345
Although a large body of research on hardiness (a personality construct with dimensions of commitment, control, and challenge) has accumulated, several fundamental issues remain unresolved. Although there are several hardiness scales, the properties of these scales have not been compared. There is debate as to whether hardiness is one or several characteristics. Research studying the pathways through which hardiness exerts its effects has not been comprehensively evaluated. Whereas critics have argued that hardiness does not buffer stress, others have suggested that hardiness buffers for working adults, for males, and in prospective analyses. There is also growing concern that hardiness is related to neuroticism. A review of the literature supports the following conclusions: The Dispositional Resilience Scale (DRS) has several advantages over alternative scales; DRS items form three factors that are consistent with hardiness theory; hardiness dimensions generally show low to moderate intercorrelations; the most common way of categorizing subjects as high or low in hardiness is not consistent with hardiness theory; hardiness does not buffer stress, and it does not buffer stress for working adults, for males, or in prospective analyses; both old and new hardiness scales inadvertently measure neuroticism. Recommendations for future research are provided. 相似文献