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981.
Previous studies on visual working memory (VWM) have primarily investigated memory for an array presented for a single moment. Here, we examined VWM for two arrays separated by a 1,100-msec interval. We focused on the allocation of VWM capacity to the two arrays as a function of dynamic events inserted between them. During the interval, irrelevant dots moved to form three types of motion: (1) coherent (apparent) motion that connected Arrays 1 and 2, (2) jumpy motion, or (3) coherent motion with two disconnected segments. Results showed that VWM for Array 2’s locations was better than for Array 1’s, especially when the arrays were connected by coherent motion. We suggest that coherent motion between two temporally disparate arrays connects the arrays into a single visual event VWM is then biased toward remembering the more recent state of the event.  相似文献   
982.
The inhibition of predatory behavior observed during the "prawn-in-the-tube" procedure has been extensively used in studies of cuttlefish learning. The present study examines the effect of age on the conditioning of this response in the cuttlefish, Sepia officinalis. Data show that a significant increase in acquisition performance occurs between 15 and 21 days of age. The retention curves in 8- and 15-day-old cuttlefish show a monotonic memory process, presumably reflecting the presence of only short-term memory. In 21-day-old cuttlefish, there are two distinct processes which could be a labile short-term memory, and a subsequent intermediate memory. These mnesic systems seem to become more effective over the course of post-embryonic development. Moreover, the retention curves obtained in the oldest cuttlefish (30- and 90-day-old) bear a close resemblance to that observed in adults. These behavioral findings will allow further work on the cellular and molecular mechanisms of learning and memory in the cuttlefish.  相似文献   
983.
Several evidences suggest that brain histamine is involved in memory consolidation but the actual contribution of the hippocampal histaminergic system to this process remains controversial. Here, we show that when infused into the CA1 region of the dorsal hippocampus immediately after training in an inhibitory avoidance task, but not later, histamine induced a dose-dependent promnesic effect without altering locomotor activity, exploratory behavior, anxiety state or retrieval of the avoidance response. The facilitatory effect of intra-CA1 histamine was mimicked by the histamine N-methyltransferase inhibitor SKF-91844 as well as by the H2 receptor agonist dimaprit and it was blocked completely by the H2 receptor antagonist ranitidine. Conversely, the promnesic action of histamine was unaffected by the H1 receptor antagonist pyrilamine, the H3 receptor antagonist, thioperamide, and the NMDAr polyamine-binding site antagonist ifenprodil. By themselves, ranitidine, pyrilamine, thioperamide, and ifenprodil did not affect IA memory consolidation. Our data indicate that, when given into CA1, histamine enhances memory consolidation through a mechanism that involves activation of H2 receptors; however, endogenous CA1 histamine does not seem to participate in the consolidation of IA memory at least at the post-training times analyzed.  相似文献   
984.
In this study the authors used cluster analysis to create racial identity profiles for a sample of Asian Americans using the People of Color Racial Identity Attitudes Scale (PCRIAS). A four-cluster solution was chosen: each cluster corresponded to one PCRIAS subscale and was named accordingly. Scores on the Asian American Racism-Related Stress Inventory and the Color-Blind Racial Attitudes Scale were compared across clusters. As expected, the Dissonance and Immersion clusters were characterized by relatively high racism-related stress and low levels of color-blind attitudes; the Conformity cluster showed roughly the opposite pattern. Surprisingly, the Internalization cluster showed a pattern similar to that for Conformity and thus may reflect "pseudoindependence" as discussed by Helms.  相似文献   
985.
In this cross-sectional study the authors examine condom use attempts and condom use among 305 high-risk, low-income African American women who reported having a main partner. Women who had recently attempted to convince their main partner to use condoms were almost 10 times more likely to have recently used condoms with their partner than women who had not made an attempt. Among the subsample of 116 women who had recently made a condom use attempt with their main partner, having a history of childhood abuse and having one's main partner raise infidelity questions in response to the condom use attempt were negatively associated with recent condom use with this partner. Findings provide initial insights into the importance of women's condom use attempts, as well as subgroups of women who may encounter special challenges convincing their main partner to use condoms.  相似文献   
986.
This study investigated cardiovascular reactivity of hypertensive adults during periods of emotional stress. Two types of instructions were given at different moments, to the same subject, either to express or to suppress feelings during role-play. Expressing, but not inhibiting, emotions elicited significantly higher reactivity during responding to negative scenes, followed by responding during the positive interactions. Blood pressure increases in both expressing and inhibiting conditions, were also found during the instruction periods. Results indicated that socially demanding situations represent a stressor whose effects may vary depending on whether or not respondents regulate expression of emotions. It is suggested that the difficulty in expressing emotions found in some hypertensive individuals may have the function of controlling or reducing blood pressure reactivity.  相似文献   
987.
The inhibitor of monoaminooxydase isatin and the ligand of B-receptors cholecystokinin-4 play a significant role in the suppression and induction of depressive and anxiety states. We induced the formation of auto-antibodies to these compounds against their conjugates with antigen-carrier by immunization of white rats. The result was long-term (more than 2 months) stimulation of depressive and anxiety behavior after immunization to isatin and, in contrast, the suppression of such behavior after immunization to cholecystokinin. The perspective of immunochemical approach to long-term correction of behavior is discussed.  相似文献   
988.
The paper describes the development of a short Spanish-language version of the General Well-Being Questionnaire (GWBQ; Cox and Gotts, 1987), based on the 12 items of its Worn Out scale. Research has shown the English-version Worn Out scale to be sensitive to aspects of the design and management of work. This study aimed to test its cross-cultural consistency in a Spanish-language workplace context. The data were collected from a sample of 229 workers in Valencia (Spain). Confirmatory Factor Analyses showed the factorial validity, reliability, and concurrent validity of the new Spanish version to be adequate. The sensitivity of the new measure to safety behavior and the reporting of accidents was also assessed and shown to be good. The new questionnaire extends the usefulness of the parent questionnaire to occupational health psychology research in the Spanish language by offering a short assessment tool appropriate for workplace studies.  相似文献   
989.
This exploratory study was an in-depth examination of Mexican American adolescents' relationships with nonparental adults. Qualitative interviews with 10 Mexican American adolescents revealed 23 nonparental adults who served a mentoring function in their lives. Six of these nonparental adults were also interviewed. Data analyses were conducted using a grounded theory approach so that the relationships were described in participants' words and experiences. The nonparental adults identified by adolescents included siblings, extended family members, older peers, and institutional figures. The support provided took many different forms, from emotional to informational/experiential support, to modeling behavior, for example. Further, adolescents were supported in eight different areas of their lives. Participants also discussed the perceived benefits of these relationships for adolescents. Future research directions and implications for youth programming are discussed.  相似文献   
990.
This paper explores the role of maternal influences on the acquisition of a tool-using task in wild chimpanzees (Pan troglodytes schweinfurthii) in order to build on and complement previous work done in captivity. Young chimpanzees show a long period of offspring dependency on mothers and it is during this period that offspring learn several important skills, especially how to and on what to forage. At Gombe National Park, one skill that is acquired during dependency is termite-fishing, a complex behavior that involves inserting a tool made from the surrounding vegetation into a termite mound and extracting the termites that attack and cling to the tool. All chimpanzees observed at Gombe have acquired the termite-fishing skill by the age of 5.5 years. Since the mother is the primary source of information throughout this time period, I investigated the influence of mothers' individual termite-fishing characteristics on their offsprings' speed of acquisition and proficiency at the skill once acquired. Mother's time spent alone or with maternal family members, which is highly correlated to time spent termite-fishing, was positively correlated to offspring's acquisition of critical elements of the skill. I also investigated the specific types of social interactions that occur between mothers and offspring at the termite mound and found that mothers are highly tolerant to offspring, even when the behavior of the offspring may disrupt the termite-fishing attempt. However, no active facilitation by mothers of offsprings' attempts were observed. Electronic Supplementary Material Electronic supplementary material Supplementary material is available for this article at http://dx.doi.org/10.1007/s10071-005-0002-7 and accessible for authorised users.  相似文献   
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