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951.
952.
The paper states the goal of this special issue and briefly summarizes the topics of the papers addressed in this issue. 相似文献
953.
954.
Malkki HA Donga LA de Groot SE;NeuroBSIK Mouse Phenomics Consortium Battaglia FP Pennartz CM 《Neurobiology of learning and memory》2011,96(2):280-287
Extinction of instrumental responses is an essential skill for adaptive behavior such as foraging. So far, only few studies have focused on extinction following appetitive conditioning in mice. We studied extinction of appetitive operant lever-press behavior in six standard inbred mouse strains (A/J, C3H/HeJ, C57BL/6J, DBA/2J, BALB/cByJ and NOD/Ltj) and eight recombinant inbred mouse lines. From the response rates at the end of operant and extinction training we computed an extinction index, with higher values indicating better capability to omit behavioral responding in absence of reward. This index varied highly across the mouse lines tested, and the variability was partially due to a significant heritable component of 12.6%.To further characterize the relationship between operant learning and extinction, we calculated the slope of the time course of extinction across sessions. While many strains showed a considerable capacity to omit responding when lever pressing was no longer rewarded, we found a few lines showing an abnormally high perseveration in lever press behavior, showing no decay in response scores over extinction sessions.No correlation was found between operant and extinction response scores, suggesting that appetitive operant learning and extinction learning are dissociable, a finding in line with previous studies indicating that these forms of learning are dependent on different brain areas. These data shed light on the heritable basis of extinction learning and may help develop animal models of addictive habits and other perseverative disorders, such as compulsive food seeking and eating. 相似文献
955.
Valladolid-Acebes I Stucchi P Cano V Fernández-Alfonso MS Merino B Gil-Ortega M Fole A Morales L Ruiz-Gayo M Del Olmo N 《Neurobiology of learning and memory》2011,95(1):80-85
It has been suggested that hyperglycemia and insulin resistance triggered by energy-dense diets can account for hippocampal damage and deficits of cognitive behaviour. We wonder if the impairment of learning and memory processes detected in diet-induced obese (DIO) mice is linked to diet composition itself. With this purpose we have evaluated learning performance in mice undergoing a short-term high-fat (HF) treatment, which leads to a pre-obese state characterized by increased adiposity without significant changes of glucose and insulin plasma levels. C57BL/6J mice were fed either a HF (45 kcal% from fat) or control diet (10 kcal% from fat) during 8 weeks. Learning performance was evaluated by using the four-arm baited version of the eight-arm radial maze test (RAM). Mice were trained to learn the RAM protocol and then memory was tested at different time-points. Time spent to consume food placed in baited arms and errors committed to find them were measured in all sessions. DIO mice significantly spent more time in learning the task and made a greater number of errors than controls. Moreover, retention tests revealed that both working and total memory errors were also more numerous in DIO mice. The current results show that short-term DIO impairs spatial learning and suggest that impairment of hippocampal learning elicited by HF diets might be perceptible before metabolic alterations linked to obesity develop. 相似文献
956.
Maton KI Wimms HE Grant SK Wittig MA Rogers MR Vasquez MJ 《Cultural diversity & ethnic minority psychology》2011,17(1):68-78
A national, Web-based survey of 1,219 African American, Latina/o, Asian American, and European American psychology graduate students revealed both similarities and differences in experiences and perspectives. Mentoring was found to be the strongest predictor of satisfaction across groups. Academic supports and barriers, along with perceptions of diversity within the academic environment, were also important predictors of satisfaction. Students of color perceived less fairness of representation of their ethnic group within psychology than European American students, and a greater linkage between aspects of the graduate school experience and their ethnicity. Limitations of the study and implications for future research and action are discussed. 相似文献
957.
ROBIN I. M. DUNBAR 《Personal Relationships》2011,18(3):439-452
Communication is important in preventing social relationships from decaying over time. This study examined the effects of social network size, emotional closeness, and type of relationship (kinship vs. friendship) on communication patterns in the social networks of 251 women. Participants with large kin networks had longer times to last contact to both kin and friends. Participants with high levels of emotional closeness in their networks had shorter times to last contact. The effect of emotional closeness on time to last contact was greater for kin than for friends. These results demonstrate that time to last contact is closely tied to emotional closeness and suggest that the costs of maintaining kin relationships are lower than the costs of maintaining friendships. 相似文献
958.
In communities of high biodiversity, the ability to distinguish predators from non-predators is crucial for prey success.
Learning often plays a vital role in the ability to distinguish species that are threatening from those that are not. Many
prey animals learn to recognise predators based on a single conditioning event whereby they are exposed to the unknown predator
at the same time as alarm cues released from injured conspecifics. The remarkable efficiency of such learning means that recognition
mistakes may occur if prey inadvertently learn that a species is a predator when it is not. Latent inhibition is a means by
which prey that are pre-exposed to an unknown species in the absence of negative reinforcement can learn that the unknown
animal is likely not a threat. Learning through latent inhibition should be conservative because mistakenly identifying predators
as non-predators can have fatal consequences. In this study, we demonstrated that a common coral reef fish, lemon damselfish,
Pomacentrus moluccensis can learn to recognise a predator as non-threatening through latent inhibition. Furthermore, we showed that we could override
the latent inhibition effect by conditioning the prey to recognise the predator numerous times. Our results highlight the
ability of prey fish to continually update the information regarding the threat posed by other fishes in their vicinity. 相似文献
959.
The trap tube is a classic test of causal reasoning abilities in animals in the physical domain. Recently, a modified version
of this task improved its diagnostic capacity and allowed testing of non-tool-using animals. We used this modified two-trap
tube task to compare the cognition of two Darwin’s finch species: the woodpecker finch, Cactospiza pallida, a tool-using species, and the small tree finch, Camarhynchus parvulus, a closely related non-tool-using species. Not all woodpecker finches use tools in nature, and we therefore also tested non-tool-using
individuals to assess the effect of experience on trap tube performance. No small tree finches and only two non-tool-using
woodpecker finches solved the initial task which was operated using a pre-inserted piston. One tool-using woodpecker finch
solved the task when allowed to use its own tool instead of the pre-inserted piston. The fact that none of these subjects
transferred their knowledge when the features of the task changed, suggests that in this species, neither experience using
tools nor the genetic composition of a tool-user are associated with the general physical cognitive skills required to solve
the trap tube task. 相似文献
960.
A Tuesday in the life of a flourisher: the role of positive emotional reactivity in optimal mental health 总被引:1,自引:0,他引:1
Flourishing--a state of optimal mental health--has been linked to a host of benefits for the individual and society, including fewer workdays lost and the lowest incidence of chronic physical conditions. The aim of this paper was to investigate whether and how routine activities promote flourishing. The authors proposed that flourishers thrive because they capitalize on the processes featured in the broaden-and-build theory of positive emotions, specifically by experiencing greater positive emotional reactivity to pleasant events and building more resources over time. To test these hypotheses, the Day Reconstruction Method (DRM) was administered to a prescreened community sample of adults (n = 208), and they were recontacted two to three months later. Results showed that relative to those who did not flourish or were depressed, people who flourish generally responded with bigger "boosts" in positive emotions in response to everyday, pleasant events (helping, interacting, playing, learning, spiritual activity), and this greater positive emotional reactivity, over time, predicted higher levels of two facets of the cognitive resource of mindfulness. In turn, these higher levels of mindfulness were positively associated with higher levels of flourishing at the end of study, controlling for initial levels of flourishing. These results suggest that the promotion of well-being may be fueled by small, yet consequential differences in individuals' emotional experience of pleasant everyday events. Additionally, these results underscore the utility of the broaden-and-build theory in understanding the processes by which flourishing is promoted and provide support for a positive potentiation perspective. 相似文献