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Jose Prados Beatriz Alvarez Joanna Howarth Katharine Stewart Claire L. Gibson Claire V. Hutchinson Andrew M. J. Young Colin Davidson 《Animal cognition》2013,16(2):177-186
The learning abilities of planarian worms (Dugesia tigrina) were assessed by using a number of Pavlovian conditioning paradigms. Experiment 1 showed that planaria were susceptible to basic conditioning in that they readily developed a conditioned response to a change in ambient luminance when it was consistently paired with an electric shock over a number of trials. In Experiment 2, the change in luminance was presented in a compound with a vibration stimulus during conditioning. Subsequent tests revealed poor conditioning of the elements compared with control groups in which the animals were conditioned in the presence of the elements alone, an instance of overshadowing. In Experiment 3, pre-training of one of the elements before compound conditioning resulted in blocking of learning about the other element. These results add to other studies that have reported cue competition effects in animal species belonging to different phyla (chordate, mollusk, arthropod), suggesting that learning in these phyla could be ruled by similar principles. The results are discussed adopting an evolutionary-comparative approach. 相似文献
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As a result of our technological advances in space exploration, human enterprise is no longer limited to the confines of planet Earth. Although several philosophical approaches to environmental ethics have already been advocated for human encounters with other planets such as Mars, it may be argued that various religious worldviews will significantly influence these suggested value systems. In this article, we present an Eastern Orthodox Christian interpretation of Creation and explore the theological meaning of the human vocation as Priests of Creation. An appropriate application of these two principles provides a theological basis for an interplanetary eco-praxis. 相似文献
787.
Alexei V. Nesteruk 《Theology & Science》2013,11(4):462-470
ABSTRACTThis paper addresses the question of the possibility of multiple species-specific incarnations of God in the societies of extraterrestrial beings (if they exist) on exoplanets, proposed for the debate in a recent volume on Astrlotheology. It gives a scientific, philosophical and theological assessment of some of its claims and concludes by formulating the position of the author on multiple incarnations in the context of modern cosmology and Orthodox theology. 相似文献
788.
David M. Sobel Jessica A. Sommerville Lea V. Travers Emily J. Blumenthal Emily Stoddard 《Journal of cognition and development》2013,14(4):262-284
Three experiments examined whether preschoolers recognize that the causal properties of objects generalize to new members of the same set given either deterministic or probabilistic data. Experiment 1 found that 3- and 4-year-olds were able to make such a generalization given deterministic data but were at chance when they observed probabilistic information. Five-year-olds reliably generalized in both situations. Experiment 2 found that 4-year-olds could make some probabilistic inferences, particularly when comparing sets that had no efficacy with sets in which some members had efficacy. Children had some difficulty discriminating between completely effective sets and stochastic ones. Experiment 3 examined whether 3- and 4-year-olds could reason about probabilistic data when provided with information about the experimenter's beliefs about causal outcomes. Children who were more successful on standard false-belief measures were more likely to respond as if the data were deterministic. These data suggest that children's probabilistic inferences develop into early elementary school, but preschoolers might have some understanding of probability when reasoning about causal generalization. 相似文献
789.
Chris A. Lawson Anna V. Fisher David H. Rakison 《Journal of cognition and development》2013,14(2):236-251
Young children are able to categorize animals on the basis of unobservable features such as shared biological properties (e.g., bones). For the most part, children learn about these properties through explicit verbalizations from others. The present study examined how such input impacts children's learning about the properties of categories. In a training study with thirty-six 2.5-year-olds (Mage = 2;9), we tested the prediction that a relatively small amount of input highlighting the importance of unobservable properties would lead to a gradual shift in children's use of these properties for categorization. Children with no initial categorization bias were trained to categorize either on the basis of shared unobservable properties or shared observable properties. During 3 days of training, children gradually developed a categorization bias in the direction of the property type for which they received training and sustained this bias more than a week after training. Also, a set of children who exhibited an initial perceptual bias showed an abrupt change in how they categorized after only 1 training session. 相似文献
790.
David Brang Luke E. Miller Marguerite McQuire V. S. Ramachandran Seana Coulson 《Cognitive processing》2013,14(4):429-434
Time-space synesthesia is a variant of sequence–space synesthesia and involves the involuntary association of months of the year with 2D and 3D spatial forms, such as arcs, circles, and ellipses. Previous studies have revealed conflicting results regarding the association between time-space synesthesia and enhanced spatial processing ability. Here, we tested 15 time-space synesthetes, and 15 non-synesthetic controls matched for age, education, and gender on standard tests of mental rotation ability, spatial working memory, and verbal working memory. Synesthetes performed better than controls on our test of mental rotation, but similarly to controls on tests of spatial and verbal working memory. Results support a dissociation between visuo-spatial imagery and spatial working memory capacity, and suggest time-space synesthesia is associated only with enhanced visuo-spatial imagery. These data are consistent with the time-space connectivity thesis that time-space synesthesia results from enhanced connectivity in the parietal lobe between regions supporting the representation of temporal sequences and those underlying visuo-spatial imagery. 相似文献