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991.
In this target article the following hypotheses are discussed: (1) Colour is autonomous: a perceptuolinguistic and behavioural universal. (2) It is completely described by three independent attributes: hue, brightness, and saturation: (3) Phenomenologically and psychophysically there are four unique hues: red, green, blue, and yellow; (4) The unique hues are underpinned by two opponent psychophysical and/or neuronal channels: red/green, blue/yellow. The relevant literature is reviewed. We conclude: (i) Psychophysics and neurophysiology fail to set nontrivial constraints on colour categorization. (ii) Linguistic evidence provides no grounds for the universality of basic colour categories. (iii) Neither the opponent hues red/green, blue/yellow nor hue, brightness, and saturation are intrinsic to a universal concept of colour. (iv) Colour is not autonomous. 相似文献
992.
993.
MJ Stillman B Shukitt-Hale BP Coffey A Levy HR Lieberman 《Stress (Amsterdam, Netherlands)》1997,1(4):191-200
Hippocampal extracellular acetylcholine (ACh) and choline levels were evaluated using in vivo microdialysis in male Fischer 344 rats before, during, and following an 80-min exposure to two different stress conditions. Measurements were taken in rats restrained and immersed in a water bath containing either 37 degreesC (normothermic-restraint) or 20 degreesC (cold-restraint) water. Results were compared to normothermic-freely-moving rats. Cold-restrained rats displayed decreased ACh levels during cold exposure relative to both normothermic-restrained and normothermic-freely-moving rats. By the end of the cold exposure period and following removal from cold, ACh levels had returned to near-baseline values. Normothermic-restrained rats had levels similar to those of normothermic-freely-moving rats, except for a marked increase in ACh following removal from restraint. Cold-restrained rats displayed a gradual elevation in choline levels during cold stress, followed by a gradual decline after stress termination, whereas both normothermic-restrained and normothermic-freely-moving rats displayed gradual decreases during the microdialysis session. These findings demonstrate that central cholinergic neurotransmission can be altered by the application of, and removal from, acute stressors. In addition, the results suggest a possible relationship between the magnitudes of both the stressor and its cholinergic consequences. 相似文献
994.
995.
During the past decade the application of elementary principles of behavior have become a standard in the classroom teacher's repertoire of behavior change strategies. Unfortunately, the application of more advanced principles of behavior derived through basic behavioral research lies as an untapped resource for classroom teachers. Nowhere is this more apparent than in the use of systematic procedures to deliver reinforcers to enhance academic performance. In this paper we provide educators with information on the use of reinforcement schedules in academic settings. Various schedules of reinforcement are presented along with examples of their application in applied settings. 相似文献
996.
Thirty-five current therapy clients, 47 former clients, and 42 college students with no therapy experience rated 27 items in terms of importance for inclusion in informed consent discussions. The current and former client samples rated information about inappropriate therapeutic techniques, confidentiality, and the risks of alternative treatments as most important, and information about the personal characteristics of the therapist and the therapist's degree as least important. The results of this study provide evidence for differential informed consent disclosure practices. 相似文献
997.
Smith DH 《Ethics & behavior》1997,7(2):137-147
Religious traditions can be drawn on in a number of ways to illuminate discussions of the moral standing of animals and the ethical use of animals in scientific research. I begin with some general comments about relevant points in the history of major religions. I then briefly describe American civil religion, including the cult of health, and its relation to scientific research. Finally, I offer a critique of American civil religion from a Christian perspective. 相似文献
998.
999.
Ruben C. Gur J.Daniel Ragland Lyn Harper Mozley P.David Mozley Robin Smith Abass Alavi Warren Bilker Raquel E. Gur 《Brain and cognition》1997,33(3):388-414
Functional neuroimaging has been used to investigate neural substrates of mnemonic processes, and cerebral blood flow (CBF) measures have been sensitive to activation with memory tasks. Studies of memory with two-dimensional133Xenon clearance techniques found that word and face recognition tasks produced contralateral CBF changes in mid-temporal cortical regions. This study replicated the activation paradigm, expanding to the three-dimensional resolution of positron emission tomography (PET). Word and face recognition, and a control baseline task were administered to 19 healthy right-handed volunteers (11 men, 8 women) during successive 10 min PET15O-water measures of CBF. Quantitative CBF rates were calculated with the arterial input function and the equilibrium model. Redistributions of blood flow were compared across tasks using both absolute and relative (region/whole brain) CBF.Replicating the133Xenon clearance findings, CBF was “appropriately” lateralized during task performance (left–right for words > left–right for faces) in the mid-temporal region. Contrary to predictions, the recognition tasks did not activate expected mesolimbic or prefrontal areas. The task-induced CBF changes also correlated with performance. Bilateral CBF in mid-temporal and parahippocampal gyrus regions of interest correlated with the ability to correctly identify word targets (sensitivity). Left-lateralized CBF in the amygdala and hippocampus correlated with better word sensitivity as well as specificity (ability to correctly reject foils). Complementally, right-lateralized CBF in the parahippocampal gyrus correlated with better face specificity performance. In addition, left-lateralized CBF in the amygdala and right-lateralized CBF in the parahippocampal gyrus and hippocampus correlated with “mental effort” indices (task performance relative to basal ability) for word and face memory tasks, respectively. Thus, whereas this recognition task showed the expected lateralized increase in the mid-temporal region and not in frontal and limbic areas, lateralized activation in some of these areas was associated with better performance. Exploratory analyses on other regions showed lateralized changes in one additional temporal region, the occipital-temporal, and several limbic regions. 相似文献
1000.
Socializing Epistemology: The Social Dimensions of Knowledge, Frederick F. Schmitt, Ed., 1994. Lanham, MD, Rowman and Littlefield, ix + 315 pp., US$22.95, ISBN: 0847679594
A Dynamic Systems Approach to the Development of Cognition and Action, Esther Thelen & Linda B. Smith. Cambridge, MA, MIT Press, xxii + 376 pp., $50, ISBN 0–262–20095–3 cloth
From Kant to Hilbert: A Source Book in the Foundations of Mathematics, William B. Ewald, Ed., 1996. Oxford, Oxford University Press. xviii+ 1340 pp., £195.00, two volumes, ISBN 0–19–853271–7 (the set) 相似文献