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881.
Studies concerning the perceptual processes of animals are not only interesting, but are fundamental to the understanding of other developments in information processing among non-humans. Carefully used visual illusions have been proven to be an informative tool for understanding visual perception. In this behavioral study, we demonstrate that cuttlefish are responsive to visual cues involving texture gradients. Specifically, 12 out of 14 animals avoided swimming over a solid surface with a gradient picture that to humans resembles an illusionary crevasse, while only 5 out of 14 avoided a non-illusionary texture. Since texture gradients are well-known cues for depth perception in vertebrates, we suggest that these cephalopods were responding to the depth illusion created by the texture density gradient. Density gradients and relative densities are key features in distance perception in vertebrates. Our results suggest that they are fundamental features of vision in general, appearing also in cephalopods.  相似文献   
882.
How should one attribute epistemic credit to an agent, and hence, knowledge, when cognitive processes include an extensive use of human or mechanical enhancers, informational tools, and devices which allow one to complement or modify one's own cognitive system? The concept of integration of a cognitive system has been used to address this question. For true belief to be creditable to a person's ability, it is claimed, the relevant informational processes must be or become part of the cognitive character of the agent, as a result of a process of enculturation. We argue that this view does not capture the role of sensitivity to epistemic norms in forming true beliefs. An analysis of epistemic actions, basic and extended, is proposed as offering an appropriate framework for crediting an agent with knowledge.  相似文献   
883.
We herein explore the perception of the geographic environment and analyse the mechanisms that constrain the cognitive processing of spatial information in general. Our guiding theoretical background assumption is that the structure of the spatial environment is a cognitively robust and mutually constrained threefold system relating (1) cognitive topology (comprised of a path and place structure of spatial information and constrained by reference frame-based factors), (2) experience-based functional knowledge (including the effects of socio-economic factors, frequency and familiarity) and (3) linguistic representations (primarily encoded in the prepositional system of a natural language). Here, we focus on (2), i.e. the effect of functional knowledge on the process of acquiring spatial knowledge. We empirically tested adolescents aged 12–17 years to explore the interaction between frequency, familiarity and functional knowledge from a developmental point of view. The social factors we explore are precisely defined and parameterized in our results (exposure to a particular urban area, place of residence, gender, age and factors relating to the environmental and social quality of the local area). Our research shows that there are divergences between the so-called objective topology and the cognitive typology of the urban environment that are significantly constrained by intensity of interactions with environment, number of functionally significant places within particular area and age from a developmental perspective in terms of spatial knowledge acquisition.  相似文献   
884.
In a series of preferential-looking experiments, infants 5 to 6 months of age were tested for their responsiveness to crossed and uncrossed horizontal disparity. In Experiments 1 and 2, infants were presented with dynamic random dot stereograms displaying a square target defined by either a 0.5° crossed or a 0.5° uncrossed horizontal disparity and a square control target defined by a 0.5° vertical disparity. In Experiment 3, infants were presented with the crossed and the uncrossed horizontal disparity targets used in Experiments 1 and 2. According to the results, the participants looked more often at the crossed (Experiment 1), as well as the uncrossed (Experiment 2), horizontal disparity targets than at the vertical disparity target. These results suggest that the infants were sensitive to both crossed and uncrossed horizontal disparity information. Moreover, the participants exhibited a natural visual preference for the crossed over the uncrossed horizontal disparity (Experiment 3). Since prior research established natural looking and reaching preferences for the (apparently) nearer of two objects, this finding is consistent with the hypothesis that the infants were able to extract the depth relations specified by crossed (near) and uncrossed (far) horizontal disparity.  相似文献   
885.
Given the barriers to conducting long-term assessment of neurocognitive and psychosocial functioning of those treated in infancy for central nervous system (CNS) tumors, a multi-site feasibility study was conducted. The primary objective was to demonstrate that it is feasible to identify, locate and assess the functioning of children treated on the same protocol 10-years post-treatment. Six sites obtained institutional approval, identified and recruited subjects, and obtained comprehensive neurocognitive and psychosocial data. All feasibility objectives were met. Barriers to participation included length of time for Institutional Review Board submission and review, clinical demands, limited eligible participants at individual institutions, difficulty locating long-term subjects and stipend/reimbursement concerns. Results indicate that long-term studies are feasible and essential given the need to address long-term issues of children treated at a young age for CNS tumors, especially as they relate to later academic and vocational planning, but require significant coordination and commitment of cooperative group and institutional resources.  相似文献   
886.
Recent research is providing family therapists with new information about the complex interaction between an individual's biological makeup and his/her social and physical environment. Family and social relationships, particularly during sensitive periods early in life, can affect a child's biological foundation. Additionally, stress during the early years can have a lasting effect on an individual's physical and mental health and contribute to the onset of severe mental illness. Community programs have been developed to intervene early with families who have an at‐risk child to prevent or minimize the onset of mental illness including providing partnerships with at‐risk mothers of infants to shape attachment relationships. Programs are also developing individual and family interventions to prevent the onset of psychosis. Practicing family therapists can incorporate emerging neuroscience and early intervention research and leverage the growing base of community programs to enhance the effectiveness and sustainability of mental health outcomes for clients. Additionally, family therapy education programs should broaden student training to incorporate the growing body of information about how family relationships affect individual mental health development.  相似文献   
887.
888.
This randomized intervention trial examined the effects of yearly Family Check-Ups (FCUs) and tailored parent management training on parent report of problem behavior from age 2 to 5 years and teacher report of oppositional behavior at age 7.5. A multiethnic risk sample of 731 families in 3 distinct geographical settings who were receiving assistance from the Women, Infants, and Children Nutritional Supplement (WIC) program were randomly assigned to a yearly FCU. Intention to treat (ITT) analyses were used to examine overall intervention effects, and complier average causal effect (CACE) modeling was used to examine the effects of annual intervention engagement in the FCU on parent reports of child problem behavior from age 2 to 5 and teacher reports of problem behavior at age 7.5. ITT intervention effects were found regarding parent report at ages 2 to 5 and teacher report at age 7.5, indicating less growth in problem behavior for children in the intervention group than for those in the control group. CACE modeling of intervention engagement revealed that the effect sizes on parent- and teacher-reported problem behavior increased as a function of the number of yearly FCUs caregivers participated in. Findings suggest that embedding yearly FCU services within the context of social, health, and educational services in early childhood can potentially prevent early-onset trajectories of antisocial behavior. The increases in effect size with successive FCU engagement underscores the importance of a motivational approach to parenting support among high-risk families.  相似文献   
889.
We examine the use of the notion of natural selection in the philosophical debate on functions in biology. This debate has been largely shaped by the way in which different accounts assess various selective pressures in justifying claims about biological functions. Cummins (Functions: new essays in the philosophy of psychology and biology. Oxford University Press, Oxford, pp 157–172, 2002), one of the main proponents of the causal role account of biological functions, argues that a correctly understood neo-Darwinian notion of natural selection has nothing to do with functional talk in biology. In this paper, we counter Cummins’ account by showing that progress in the molecular approaches to evolutionary biology—specifically scientific data available in neo-functionalization research—offers valuable support to the etiological selectionist approach to functions in biological and biologically-related sciences. Finally, we use the presented data to build our own account of biological functions, which tries to avoid the wrong turns taken by both major strands in the biological function debate, namely causal role and etiological accounts. According to our account, the function of a certain gene or a protein in the biological system that contains it is a particular causal activity, or a group of causal activities whose manifestation is in a specific way determined by corresponding mechanisms of genetic expression. Also, we argue that in many important cases this particular expression of genetic activity was positively selected at a certain point in evolutionary history. Since we take selection as an important but not the only factor that grounds biological functions, we are committed to a weak etiological account.  相似文献   
890.
The aim of this paper is to offer an account of epistemic justification suitable for the context of theory pursuit, that is, for the context in which new scientific ideas, possibly incompatible with the already established theories, emerge and are pursued by scientists. We will frame our account paradigmatically on the basis of one of the influential systems of epistemic justification: Laurence Bonjour’s coherence theory of justification. The idea underlying our approach is to develop a set of criteria which indicate that the pursued system is promising of contributing to the epistemic goal of robustness of scientific knowledge and of developing into a candidate for acceptance. In order to realize this we will (a) adjust the scope of Bonjour’s standards—consistency, inferential density, and explanatory power, and (b) complement them by the requirement of a programmatic character. In this way we allow for the evaluation of the “potential coherence” of the given epistemic system.  相似文献   
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