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111.
Watowich Marina M. MacLean Evan L. Hare Brian Call Josep Kaminski Juliane Miklósi Ádám Snyder-Mackler Noah 《Animal cognition》2020,23(4):795-805
Animal Cognition - Across mammals, increased body size is positively associated with lifespan. However, within species, this relationship is inverted. This is well illustrated in dogs (Canis... 相似文献
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The purposes of the present study were threefold: (a) to assess the prevalence levels of anxiety and depression in a sample of Mexican migrant farm workers in the midwestern United States; (b) to explore the relationships among acculturative stress, anxiety, and depression; and (c) to examine the variables that best predict anxiety and depression. The overall sample revealed elevated levels of anxiety and depression. Migrant farm workers with heightened levels of acculturative stress were more likely to report high levels of anxiety and depression. Family dysfunction, ineffective social support, low self-esteem, lack of agreement with the decision to migrate, high education levels, high levels of acculturative stress, and high levels of anxiety were significantly associated with high depression levels. The overall findings suggest that migrant farm workers who experience elevated levels of acculturative stress may be at risk for experiencing high levels of anxiety and depression. The findings highlight the importance of establishing prevention and treatment services for migrant farm workers that aim to increase levels of emotional support, self-esteem, and coping skills. 相似文献
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Gutiérrez G. de Guzmán I. P. Martínez J. Ojeda-Aciego M. Valverde A. 《Studia Logica》2002,72(1):85-112
The tree-based data structure of -tree for propositional formulas is introduced in an improved and optimised form. The -trees allow a compact representation for negation normal forms as well as for a number of reduction strategies in order to consider only those occurrences of literals which are relevant for the satisfiability of the input formula. These reduction strategies are divided into two subsets (meaning- and satisfiability-preserving transformations) and can be used to decrease the size of a negation normal form A at (at most) quadratic cost. The reduction strategies are aimed at decreasing the number of required branchings and, therefore, these strategies allow to limit the size of the search space for the SAT problem. 相似文献
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Variability and detection of invariant structure 总被引:2,自引:0,他引:2
Gómez RL 《Psychological science》2002,13(5):431-436
Two experiments investigated learning of nonadjacent dependencies by adults and 18–month–olds. Each learner was exposed to three–element strings (e.g., pel–kicey–jic) produced by one of two artificial languages. Both languages contained the same adjacent dependencies, so learners could distinguish the languages only by acquiring dependencies between the first and third elements (the nonadjacent dependencies). The size of the pool from which the middle elements were drawn was systematically varied to investigate whether increasing variability (in the form of decreasing predictability between adjacent elements) would lead to better detection of nonadjacent dependencies. Infants and adults acquired nonadjacent dependencies only when adjacent dependencies were least predictable. The results point to conditions that might lead learners to focus on nonadjacent versus adjacent dependencies and are important for suggesting how learning might be dynamically guided by statistical structure. 相似文献
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The contextual modulation of conditioned taste aversions by the physical environment and time of day is similar
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Morón I Manrique T Molero A Ballesteros MA Gallo M Fenton A 《Learning & memory (Cold Spring Harbor, N.Y.)》2002,9(5):218-223
In a pair of experiments, we have compared the ability of changes of place (Exp. 1) and changes of time of day (Exp. 2) to separately modulate learned saline-aversion memory phenomena in rats. Neither a spatial nor a temporal change disrupted latent inhibition using the present behavioral procedure. However, pre-exposure to the taste increased the contextual control of the learned aversion expression. The aversion reappeared in the place or at the time of conditioning after extinction in a different context. The results indicate that environmental and temporal contexts can independently, but similarly modulate taste aversion learning. 相似文献
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The positive effect of postlearning sleep on memory consolidation as well as the relationship between sleep-related memory processes and the hippocampal formation are increasingly clarified topics in neurobiology. However, the possibility of a stable relationship between waking mnemonic performance and sleep-dependent hippocampal electric activity is unexplored. Here we report a correlative analysis between sleep-dependent parahippocampal-hippocampal (pHip-Hip) electric activity recorded by foramen ovale (FO) electrodes and different types of memory performances in epileptic patients. Psychological testing was performed days or weeks before electrophysiological recordings. The relative spectral power of the slow activity (below 1.25 Hz) during deep non-REM (NREM) sleep at the right pHip-Hip region correlated positively with the visual memory performance according to Rey-Osterrieth Complex Figure Test (ROCFT). Along the posterior-anterior direction of the hippocampal formation a linear increasing of correlations was observed. The relative power of the activity below 1.25 Hz at the left pHip-Hip during phasic REM sleep correlated positively with verbal learning performance and mnemonic retention values according to ROCFT. It is concluded that the pHip-Hip structures' capacity of producing high amplitude and synchronized slow (< 1 Hz) oscillation during deep NREM sleep is related to the functional power of these structures. We hypothesize that the asymmetric (side-specific) propagation of ponto-geniculo-occipital (PGO) activity to the pHip-Hip region is related to the memory correlates of phasic REM sleep. 相似文献