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971.
Reichelt AC Lin TE Harrison JJ Honey RC Good MA 《Neurobiology of learning and memory》2011,96(2):248-253
Instrumental performance in rats with hippocampal lesions is insensitive to the degradation of action-outcome contingencies, but sensitive to the effects of selective devaluation by satiation. One interpretation of this dissociation is that damage to the hippocampus impairs the formation of context-outcome associations upon which the effect of contingency degradation, but not selective satiation, relies. Here, we provide a direct assessment of this interpretation, and showed that conditioned responding to contexts did not show sensitivity to selective satiation (Experiment 1), and confirmed that instrumental performance was sensitive to selective satiation (Experiment 2) following hippocampal cell loss. 相似文献
972.
Sanderson DJ Hindley E Smeaton E Denny N Taylor A Barkus C Sprengel R Seeburg PH Bannerman DM 《Learning & memory (Cold Spring Harbor, N.Y.)》2011,18(3):181-190
Deletion of the GluA1 AMPA receptor subunit impairs short-term spatial recognition memory. It has been suggested that short-term recognition depends upon memory caused by the recent presentation of a stimulus that is independent of contextual-retrieval processes. The aim of the present set of experiments was to test whether the role of GluA1 extends to nonspatial recognition memory. Wild-type and GluA1 knockout mice were tested on the standard object recognition task and a context-independent recognition task that required recency-dependent memory. In a first set of experiments it was found that GluA1 deletion failed to impair performance on either of the object recognition or recency-dependent tasks. However, GluA1 knockout mice displayed increased levels of exploration of the objects in both the sample and test phases compared to controls. In contrast, when the time that GluA1 knockout mice spent exploring the objects was yoked to control mice during the sample phase, it was found that GluA1 deletion now impaired performance on both the object recognition and the recency-dependent tasks. GluA1 deletion failed to impair performance on a context-dependent recognition task regardless of whether object exposure in knockout mice was yoked to controls or not. These results demonstrate that GluA1 is necessary for nonspatial as well as spatial recognition memory and plays an important role in recency-dependent memory processes. 相似文献
973.
Adding to the Mix: Integrating ELSI into a National Nanoscale Science and Technology Center 总被引:1,自引:0,他引:1
This paper describes issues associated with integrating the study of Ethical, Legal and Social Issues (ELSI) into ongoing scientific and technical research and describes an approach adopted by the authors for their own work with the center for nanophase materials sciences (CNMS) at the Oak Ridge national laboratory (ORNL). Four key questions are considered: (a) What is ELSI and how should it identify and address topics of interest for the CNMS? (b) What advantages accrue to incorporating ELSI into the CNMS? (c) How should the integration of ELSI into the CNMS take place? (d) How should one judge the effectiveness of the activity? We conclude that ELSI research is not a monolithic body of knowledge, but should be adapted to the question at hand. Our approach focuses on junctures in the R&;D continuum at which key decisions occur, avoids topics of a purely ethical nature or advocacy, and seeks to gather data in ways that permit testing the validity of generalization. Integrating ELSI into the CNMS allows dealing with topics firmly grounded in science, offers concrete examples of potential downstream applications and provides access to the scientists using the CNMS and their insights and observations. As well, integration provides the opportunity for R&;D managers to benefit from ELSI insights and the potential to modify R&;D agendas. Successful integration is dependent on the particular ELSI question set that drives the project. In this case questions sought to identify key choices, information of value to scientists, institutional attributes, key attributes of the CNMS culture, and alternatives for communicating results. The opportunity to consult with scientists on ELSI implications is offered, but not promoted. Finally, ELSI effectiveness is judged by observing the use to which research products are put within the CNMS, ORNL, and the community of external scholars. 相似文献
974.
The developing infant learns about the physical and the social world by engaging with objects and with people. In the study reported here, we investigated the relationship between infants' interactions with the physical and the social world. Three-month-old infants were trained for 2 weeks and experienced either actively manipulating objects themselves or passively having objects touched to their hands. Following active or passive experiences, spontaneous orienting towards faces and objects was compared between the trained groups and untrained 3- and 5-month-olds. It is known that the onset of reaching behavior increases infants' interest in objects. However, we report that active, self-produced reaching experiences also increase infants' spontaneous orienting towards faces, while passive experiences do not affect orienting behavior. Regression analyses provide evidence for a link between manual engagement and the development of orienting towards faces. Implications of orienting towards faces for the development of triadic interactions, joint attention, and social cognition in general are discussed. 相似文献
975.
Social responsibility is a value orientation, rooted in democratic relationships with others and moral principles of care and justice, that motivates certain civic actions. Given its relevance for building stronger relationships and communities, the development of social responsibility within individuals should be a more concerted focus for developmental scholars and youth practitioners. During childhood and adolescence, the developmental roots of individuals' social responsibility lie in the growth of executive function, empathy and emotion regulation, and identity. Efforts to cultivate children and adolescents' social responsibility in the proximal settings of their everyday lives should emphasize modeling prosocial behaviors, communicating concerns for others, and creating opportunities to practice civic skills. 相似文献
976.
Sailor KM Zimmerman ME Sanders AE 《Quarterly journal of experimental psychology (2006)》2011,64(12):2383-2391
The degree to which the typical age of acquisition (AoA) of words and word frequency have separable influences on verbal production tasks has been strongly debated. To examine the overlap between these factors in verbal fluency tasks, the performance of Alzheimer's disease (AD) patients (N = 34) and normal elderly controls (N = 36) was compared on semantic (e.g., vegetables) and letter (e.g., words that begin with F) fluency tasks. These comparisons revealed that words generated for the semantic fluency task had an earlier AoA while words generated for the letter fluency task had a higher word frequency. Differences in AoA between AD patients and controls were larger for semantic than letter fluency. These results suggest that AoA has an effect on verbal production that is independent of word frequency and that AoA has a semantic locus. 相似文献
977.
Jackson SR Parkinson A Pears SL Nam SH 《Quarterly journal of experimental psychology (2006)》2011,64(5):839-854
The intention to execute a movement can modulate our perception of sensory events, and this modulation is observed ahead of both ocular and upper limb movements. However, theoretical accounts of these effects, and also the empirical data, are often contradictory. Accounts of "active touch", and the premotor theory of attention, have emphasized how movement intention leads to enhanced perceptual processing at the target of a movement, or on the to-be-moved effector. By contrast, recent theories of motor control emphasize how internal "forward" model (FM) estimates may be used to cancel or attenuate sensory signals that arise as a result of self-generated movements. We used behavioural and functional brain imaging (functional magnetic resonance imaging, fMRI) to investigate how perception of a somatosensory stimulus differed according to whether it was delivered to a hand that was about to execute a reaching movement or the alternative, nonmoving, hand. The results of our study demonstrate that a somatosensory stimulus delivered to a hand that is being prepared for movement is perceived to have occurred later than when that same stimulus is delivered to a nonmoving hand. This result indicates that it takes longer for a tactile stimulus to be detected when it is delivered to a moving limb and may correspond to a change in perceptual threshold. Our behavioural results are paralleled by the results of our fMRI study that demonstrated that there were significantly reduced blood-oxygen-level-dependent (BOLD) responses within the parietal operculum and insula following somatosensory stimulation of the hand being prepared for movement, compared to when an identical stimulus was delivered to a nonmoving hand. These findings are consistent with the prediction of FM accounts of motor control that postulate that central sensory suppression of somatosensation accompanies self-generated limb movements, and with previous reports indicating that effects of sensory suppression are observed in higher order somatosensory regions. 相似文献
978.
The organizational justice literature has consistently documented substantial correlations between organizational justice and employee depression. Existing theoretical literature suggests this relationship occurs because perceptions of organizational (in)justice lead to subsequent psychological health problems. Building on recent research on the affective nature of justice perceptions, in the present research we broaden this perspective by arguing there are also theoretical arguments for a reverse effect whereby psychological health problems influence perceptions of organizational justice. To contrast both theoretical perspectives, we test longitudinal lagged effects between organizational justice perceptions (i.e., distributive justice, interactional justice, interpersonal justice, informational justice, and procedural justice) and employee depressive symptoms using structural equation modeling. Analyses of 3 samples from different military contexts (N? = 625, N? = 134, N? = 550) revealed evidence of depressive symptoms leading to subsequent organizational justice perceptions. In contrast, the opposite effects of organizational justice perceptions on depressive symptoms were not significant for any of the justice dimensions. The findings have broad implications for theoretical perspectives on psychological health and organizational justice perceptions. 相似文献
979.
Lamborn AB 《Journal of religion and health》2011,50(1):108-119
This article explores one of C. G. Jung’s generally neglected essays, his psychological interpretation of the Trinity, and
links up key theoretical notions with several more mainstream psychoanalytic concepts. It further uses the notions of oneness,
otherness, thirdness, and the fourth to consider the recent points of convergence between psychoanalysis and religion. 相似文献
980.
Delay to delivery of a reinforcer can decrease responding for that reinforcer and increase responding for smaller reinforcers that are available concurrently and delivered without delay; acute administration of drugs can alter responding for large, delayed reinforcers, although the impact of chronic treatment on delay discounting is not well understood. In this experiment, the effects of repeated administration of the benzodiazepine flunitrazepam were studied in 6 pigeons responding on one key to receive food that was delivered immediately and on a second key to receive a larger amount of food that was delivered following delays which increased across a single session. Pigeons responded predominantly for the large reinforcer when there were no delays and when delays were short; however, as delays increased, responding for the large reinforcer decreased. Acutely, flunitrazepam (0.32, 1.0 and 3.2 mg/kg) dose-dependently increased responding for the large reinforcer, shifting the discounting curve rightward and upward. Repeated administration of flunitrazepam (0.32, 1.0 and 3.2 mg/kg, each for six sessions, separated by one session during which vehicle was administered) did not markedly alter its effects on responding for the large reinforcer, indicating that the development of tolerance to this effect of flunitrazepam is modest under these conditions. 相似文献