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This investigation compared the neural correlates of inhibition in normal older adults (OAs) and OAs with mild cognitive impairment (MCI). It was hypothesized the MCI group would require a greater amount of resources for inhibition, and therefore display greater functional activation in specific regions of interest (ROIs). Twenty-six OAs without and 17 with MCI completed the Stroop task during functional neuroimaging, and completed additional out-of-scanner neuropsychological measures. During inhibition, there were minimal functional Magnetic Resonance Imaging (fMRI) differences found between groups in a priori specified ROIs and with post-hoc multiple regression analyses. However, these minimal differences did not survive corrected thresholds. Robust differences were found with several tasks of a neuropsychological screening battery. The results of this study suggest only very minimal group differences in fMRI activation during inhibition which may not reliably identify MCI, and this condition may be best detected by traditional neuropsychological techniques.  相似文献   
994.
Cerebral lateralization has been suggested to convey a selective advantage to individuals by enhancing their cognitive abilities. Few, however, have explicitly compared the cognitive ability of animals with strongly contrasting laterality. Here, we examined the influence of laterality on learning performance in the crimson spotted rainbowfish, Melanotaenia duboulayi, using a classical conditioning paradigm. We also compared the learning ability of wild caught and captive-reared fish to examine the influence of rearing environment on cognitive performance. Laterality was established by observing which eye fish preferred to use while viewing their mirror image. Subjects were then conditioned to associate the appearance of a red light with a food reward over 7 days. Our results revealed that left-lateralized fish learned the conditioning task faster than right-lateralized. These results provide further evidence that cerebral lateralization can play important roles in cognitive function which likely have diverse fitness consequences for animals in their natural environments.  相似文献   
995.
When stockouts restrict consumers' freedoms, two independent responses can occur: product desirability, or a reactance-based increase in the desire for the unavailable option, and source negativity, or general frustration with the source of the restriction. In four studies, we provide a novel investigation of consumer responses to stockout-restoration and examine how these two forces combine to affect consumer responses after freedoms are restored. To do so, we investigate two moderators that influence the activation and strength of product desirability and source negativity, respectively: trait reactance and attributions. While all consumers experience source negativity in response to stockouts, only consumers high in reactance experience product desirability, leading to differential responses to stockout-restoration. Compared to an in-stock condition, high reactance consumers respond positively to stockout-restoration, while low reactance consumers respond negatively to stockout-restoration, in terms of store and product evaluations and store choice. However, when high reactants attribute a stockout to the store, thereby increasing source negativity relative to product desirability, they respond negatively to stockout-restoration.  相似文献   
996.
This research examined the impact of affectivity and coping on state anxiety and positive emotions among young adults living in the Washington, DC metro area both during and after the Washington, DC sniper killings. Participants completed questionnaires during three waves of data collection: (1) during the sniper attacks (n=92); (2) within two weeks after the snipers were captured (n=45); and (3) six months later (n=43). Affectivity (measured by neuroticism) was significantly associated with state anxiety and positive emotions during all three time periods. Coping (measured by constructive thinking) predicted state anxiety and positive emotions during the shootings, but was unrelated to either outcome immediately after the attacks, and marginally related to them six months later. Consistent with the Dynamic Model of Affect, state anxiety and positive emotions were more strongly (and negatively) correlated with each other during the killings than they were after the snipers were apprehended. Taken together, these results support transactional models of stress that emphasize the interaction between dispositional and situational influences, and they suggest that affectivity reflects a fundamental set of reactions to one's environment, while coping dispositions result in more stress-specific responses. Additional theoretical and practical implications of these findings are also discussed.  相似文献   
997.
The purpose of this research was to examine the impact of worker characteristics (e.g., time spent caring for others), workplace support, and child characteristics on work family conflict among parents of atypically developing children. Participants (N = 51) were employed parents of atypically developing children who completed measures of work family conflict, workplace supports (i.e., supervisory support and organizationally supportive cultures), the availability and use of family supportive workplace programs, child characteristics, and worker characteristics. Hierarchical multiple regression analyses indicated that worker and child characteristics significantly predicted work family conflict, work in family interference, and family in work interference. In addition, workplace supports significantly predicted work family conflict and family in work interference. Implications of the results for managing the work family life interface are discussed.  相似文献   
998.
It is often the case that stimuli (or aspects of a stimulus) are referred to as being “task-irrelevant.” Here, we recount where this label originated and argue that the use of this label is at odds with the concept of “relevance” that has arisen in the contingent-capture literature. This is not merely a matter of labels, but a matter of inference: When people describe a flanker stimulus as being “task-irrelevant,” they may be (and sometimes are) tempted to infer that the conditions that were studied in the flanker task generalize to other tasks and other types of stimuli. Here, we show that this generalization is not warranted. The flanker effect exists not because attention has failed at selecting only the target from the display, but rather, the effect arises precisely because attention succeeded at selecting target-like (i.e., attentionally relevant) stimuli from the display. As a result, the flanker effect should not be used to infer how stimuli that are entirely unrelated to a participant’s main task would be processed. We propose the use of a new terminology to replace this potentially misleading label.  相似文献   
999.
Human participants searched in a dynamic three-dimensional computer-generated virtual-environment open-field search task for four hidden goal locations arranged in a diamond configuration located in a 5 × 5 matrix of raised bins. Participants were randomly assigned to one of two groups: visual pattern or visual random. All participants experienced 30 trials in which four goal locations maintained the same spatial relations to each other (i.e., a diamond pattern), but this diamond pattern moved to random locations within the 5 × 5 matrix from trial to trial. For participants in the visual pattern group, four locations were marked in a distinct color and arranged in a diamond pattern that moved to a random location independent of the hidden spatial pattern from trial to trial throughout the experimental session. For participants in the visual random group, four random locations were marked with a distinct color and moved to random locations independent from the hidden spatial pattern from trial to trial throughout the experimental session. As a result, the visual cues for the visual pattern group were consistent but not coincident with the hidden spatial pattern, whereas the visual cues for the visual random group were neither consistent nor coincident with the hidden spatial pattern. Results indicated that participants in both groups learned the spatial configuration of goal locations and that the presence of consistent but noncoincident visual cues facilitated the learning of spatial relations among locations.  相似文献   
1000.
Haines Brown 《Axiomathes》2014,24(3):291-312
The paper assumes that to be of practical interest process must be understood as physical action that takes place in the world rather than being an idea in the mind. It argues that if an ontology of process is to accommodate actuality, it must be represented in terms of relative probabilities. Folk physics cannot accommodate this, and so the paper appeals to scientific culture because it is an emergent knowledge of the world derived from action in it. Process is represented as a contradictory probability distribution that does not depend on a spatio-temporal frame. An actuality is a probability density that grounds the values of probabilities to constitute their distributions. Because probability is a conserved value, probability distributions are subject to the constraint of symmetry and must be zero-sum. An actuality is locked-in by other actualities to become a zero-sum symmetry of probability values. It is shown that the locking-in of actualities constructs spatio-temporal locality, lends actualities specificity, and makes them a contradiction. Localization is the basis for understanding empirical observation. Because becoming depends on its construction of being, processes exist as trajectories. The historical trajectories of evolution and revolution as well as the non-historical trajectory of strong emergence are how processes are observed to exist.  相似文献   
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