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981.
Reimers S Maylor EA 《Neuropsychology, development, and cognition. Section B, Aging, neuropsychology and cognition》2006,13(3-4):479-489
Deary and Der (2005) reported significant gender effects on intraindividual variability in choice reaction time (CRT), and suggested several potential causes. In their procedure it was not possible to examine RTs on a trial-to-trial basis. We therefore investigate an additional possible cause: that men and women differ in their rate of performance improvement across trials, creating an apparent difference in variability. Using data from a large online CRT study, we replicate the finding that women are more variable in RT than men. However, we also demonstrate an interaction between gender and trial number for RT: women were initially slower than men, but became faster than men across a block. When the first two trials of the block are excluded, the gender effects on RT variability disappear. 相似文献
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The purpose of the present study is to examine the applicability of a computer-generated, virtual animal to study animal cognition. Pigeons were trained to discriminate between movies of a real pigeon and a rat. Then, they were tested with movies of the computer-generated (CG) pigeon. Subjects showed generalization to the CG pigeon, however, they also responded to modified versions in which the CG pigeon was showing impossible movement, namely hopping and walking without its head bobbing. Hence, the pigeons did not attend to these particular details of the display. When they were trained to discriminate between the normal and the modified version of the CG pigeon, they were able to learn the discrimination. The results of an additional partial occlusion test suggest that the subjects used head movement as a cue for the usual vs. unusual CG pigeon discrimination.This contribution is part of the special issue ‘Animal Logics’ (Watanabe and Huber 2006) 相似文献
984.
In several species, the ability to locate a disappearing object is an adaptive component of predatory and social behaviour.
In domestic dogs, spatial memory for hidden objects is primarily based on an egocentric frame of reference. We investigated
the geometric components of egocentric spatial information used by domestic dogs to locate an object they saw move and disappear.
In experiment 1, the distance and the direction between the position of the animal and the hiding location were put in conflict.
Results showed that the dogs primarily used the directional information between their own spatial coordinates and the target
position. In experiment 2, the accuracy of the dogs in finding a hidden object by using directional information was estimated
by manipulating the angular deviation between adjacent hiding locations and the position of the animal. Four angular deviations
were tested: 5, 7.5, 10 and 15°. Results showed that the performance of the dogs decreased as a function of the angular deviations
but it clearly remained well above chance, revealing that the representation of the dogs for direction is precise. In the
discussion, we examine how and why domestic dogs determine the direction in which they saw an object disappear. 相似文献
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The idea of viewing human cognition as a rational solution to computational problems posed by the environment has influenced several recent theories of human memory. The first rational models of memory demonstrated that human memory seems to be remarkably well adapted to environmental statistics but made only minimal assumptions about the form of the environmental information represented in memory. Recently, several probabilistic methods for representing the latent semantic structure of language have been developed, drawing on research in computer science, statistics and computational linguistics. These methods provide a means of extending rational models of memory retrieval to linguistic stimuli, and a way to explore the influence of the statistics of language on human memory. 相似文献
989.
Two major non-invasive techniques in cognitive neuroscience, electroencephalography (EEG) and functional magnetic resonance imaging (fMRI), have complementary advantages with regard to their spatial and temporal resolution. Recent hardware and software developments have made it feasible to acquire EEG and fMRI data simultaneously. We emphasize the potential of simultaneous EEG and fMRI recordings to pursue new strategies in cognitive neuroimaging. Specifically, we propose that, by exploiting the combined spatiotemporal resolution of the methods, the integration of EEG and fMRI recordings on a single-trial level enables the rich temporal dynamics of information processing to be characterized within spatially well-defined neural networks. 相似文献
990.