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181.
Most evidence for the role of regular inflection as a default operation comes from languages that confound the morphological properties of regular and irregular forms with their phonological characteristics. For instance, regular plurals tend to faithfully preserve the base's phonology (e.g., rat-rats), whereas irregular nouns tend to alter it (e.g., mouse-mice). The distinction between regular and irregular inflection may thus be an epiphenomenon of phonological faithfulness. In Hebrew noun inflection, however, morphological regularity and phonological faithfulness can be distinguished: Nouns whose stems change in the plural may take either a regular or an irregular suffix, and nouns whose stems are preserved in the plural may take either a regular or an irregular suffix. We use this dissociation to examine two hallmarks of default inflection: its lack of dependence on analogies from similar regular nouns, and its application to nonroots such as names. We show that these hallmarks of regularity may be found whether or not the plural form preserves the stem faithfully: People apply the regular suffix to novel nouns that do not resemble existing nouns and to names that sound like irregular nouns, regardless of whether the stem is ordinarily preserved in the plural of that family of nouns. Moreover, when they pluralize names (e.g., the Barak-Barakim), they do not apply the stem changes that are found in their homophonous nouns (e.g., barak-brakim lightning), replicating an effect found in English and German. These findings show that the distinction between regular and irregular phenomena cannot be reduced to differences in the kinds of phonological changes associated with those phenomena in English. Instead, regularity and irregularity must be distinguished in terms of the kinds of mental computations that effect them: symbolic operations versus memorized idiosyncrasies. A corollary is that complex words are not generally dichotomizable as regular or irregular different aspects of a word may be regular or irregular depending on whether they violate the rule for that aspect and hence must be stored in memory.  相似文献   
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There is evidence that exteroceptive cues associated with drug administration elicit conditional compensatory responding (e.g., hyperalgesia in organisms with a history of morphine administration). Recently it has become apparent that, within each administration, interoceptive early-drug onset cues (DOCs) may become associated with the later, larger drug effect (intraadministration associations). The present experiments evaluated DOC-elicited conditional hyperalgesia in rats intravenously infused with morphine. The results indicated that DOC-elicited hyperalgesia contributes to tolerance to the analgesic effect of morphine, and such DOC-elicited hyperalgesia is an associative phenomenon, rather than a sensitized response to the opiate. The findings suggest that associative analyses of tolerance should acknowledge the conditional responding elicited by DOCs, and extinction-based addiction treatments should incorporate extinction of DOC-elicited conditional responding.  相似文献   
183.
Women with disabilities have low employment rates and about one-third live in poverty. They represent half of the population using either services of the vocational rehabilitation (VR) system or the welfare system, and many use both. Although both systems have made gains in improving their employment status, neither comprehensively addresses the needs of this population. Welfare policy has encouraged state level innovation and moved large numbers of people into employment in as little as five years. State welfare agencies offer a range of services specifically addressing the needs of families with children. VR agencies have decades of specific experience assisting people with disabilities gain employment. Welfare reform has been the cruise ship moving large numbers of people across an ocean. VR agencies have been the kayak builders designing specialized small craft to move specific people along tributaries. What can they learn from each other? Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   
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This study examined the effectiveness ofvisuo-motor behavior rehearsal(VMBR) as a method of reducing acute stress and improving police officer performance. Fifty-four recruits were randomly assigned to a treatment and a nontreatment condition prior to undergoing a highly stressful, critical event training scenario involving live fire. A manipulation check showed that participants who received VMBR displayed significantly lower scores on the cognitive state anxiety subscale of the Competitive State Anxiety Inventory-2; somatic state anxiety and self-confidence were unaffected by the VMBR treatment. Most importantly, participants in the VMBR training condition displayed better performance on the critical event scenario, including significantly more assailant hits. The findings are discussed with respect to the four-stage model of stress and human performance of Salas and colleagues.  相似文献   
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This study examined predictors of anxiety symptomatology among immigrant Mexican migrant farmworkers in the Midwest. Its purposes were to assess the prevalence of anxiety symptoms, to examine the relationship between acculturative stress and anxiety, and to determine the variables that best predict anxiety. Heightened levels were found for overall anxiety and in the cognitive, affective, and physiological expressions of anxiety. Elevated acculturative stress, low self-esteem, ineffective social support, lack of control and choice in living a migrant farmworker lifestyle, low religiosity, and high education were significantly related to high anxiety. Findings suggest that migrant farmworkers who experience elevated acculturative stress are susceptible to the development of anxiety-related disorders and highlight the importance of establishing prevention and treatment services for migrant farmworkers.  相似文献   
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A closer look at unicellular organisms and their behavior as autonomous and social beings sheds new light on the nature of cognition. This allows, at the same time, a search for minimal conditions that help to identify the yet unknown appearance of cognition during evolution. Positive results might also serve as principles for the construction of intelligent artefacts as striven for in artificial intelligence and cognitive robotics research. Analyzing the abilities of prokaryotes and unicellular eukaryotes and comparing them to the abilities of "higher" organisms, we conclude that common definitions of cognition are not specific enough. The attempt to define cognition by focusing on the coupling between stimulus and response and asserting that (to have cognition) it has to be indirect and modifiable fails, simply because in all organisms every reaction to a stimulus is indirect and modifiable. A definition of cognition based on such a distinction cannot hold unless one is willing to ascribe cognitive capacities also to Escherichia coli bacteria, for instance. Viewing cognition as the sum of abilities necessary for coping with a complex physical and social environment is also highly questionable, i.e. unspecific. We show that functions comparable to the cognitive functions "perception" and "memory" in higher organisms can well be identified in unicellular beings. The "architecture" of the bacterial (prokaryotic) sensorimotor apparatus is also in some structures, but particularly at the functional level, comparable with that of higher organisms and should be, as a consequence, indicative of cognition. Furthermore, we discuss other, somewhat more delimitable, phenomena like detection of identity, counting, adaptation, habituation and learning in ethological categories and compare them to findings from the microorganismic world. In this context, we argue that so-called "true learning" and the appearance of nervous systems are not break-points in the evolution of cognition. The presence of nervous systems means only a huge amplification of the recognition power of individual organisms. The molecular net that realizes the regulation and transduction of signals in unicellular beings is comparable to the processes within a neural net, and a population of unicellular organisms can be viewed as an individual, multicellular net with amplified recognition power. Finally, we show that sophisticated forms of cooperation and competition developed also in populations of unicellular organisms. This seems not to be true for the phenomena imagination (rehearsal) and introspection, also to be seen as stemming from social problem-solving needs. As for these aspects, further research is needed, however, to put them on firm scientific grounds. Zusammenfassung. Eine genaue Betrachtung einzelliger Lebewesen und ihres Verhaltens als autonome und soziale Wesen wirft neues Licht auf die Natur von Kognition. Das erlaubt gleichzeitig eine Suche nach minimalen Bedingungen, die bei der Bestimmung des Erscheinens von Kognition in der Evolution helfen. Positive Ergebnisse könnten auch als Prinzipien für die Konstruktion intelligenter Artefakte dienen, wie sie in der Künstlichen Intelligenz und der kognitiven Robotikforschung angestrebt werden. Ein Vergleich der Fähigkeiten von Einzellern mit denen von "höheren" Organismen führt uns zu dem Schluß, daß gängige Definitionen von Kognition nicht spezifisch genug sind. Der Versuch, Kognition über die Indirektheit und Modifizierbarkeit der Kopplung zwischen Reiz und Reaktion zu definieren, scheitert, weil in allen Organismen Reiz-Reaktionsverbindungen indirekt und modifizierbar sind. Eine solche Definition ist nicht haltbar, es sei denn, man ist bereit, z.B. auch Escherichia coli-Bakterien kognitive Eigenschaften zuzubilligen. Die Definition von Kognition als Summe der Eigenschaften, die notwendig sind, um in einer komplexen physikalischen und sozialen Umgebung zu bestehen, ist ebenfalls hinterfragbar und unspezifisch. Wir zeigen, daß Leistungen, die mit den Kognitionsleistungen "Wahrnehmung" und "Gedächtnis" in höheren Organismen vergleichbar sind, in Einzellern nachweisbar sind. Die sensomotorische Komplexität von Einzellern ist auch in vieler Hinsicht strukturell, vor allem aber funktionell vergleichbar mit derjenigen höherer Organismen und kann deshalb als ein Hinweis auf Kognition gewertet werden. Darüber hinaus diskutieren wir andere, abgrenzbare Phänomene, wie Erfassung von Identität, Zählen, Adaptation, Habituation und Lernen, aus der Sicht der Verhaltensforschung und vergleichen sie mit Befunden aus der Welt der Mikroorganismen. In diesem Zusammenhang bestreiten wir, daß sogenanntes "echtes Lernen" und das Erscheinen von Nervensystemen Bruchstellen in der Evolution von Kognition sind. Die Anwesenheit von Nervensystemen bedeutet nur den Übergang von Systemen mit einem relativ begrenzten (Erkennungs-) Potential zu solchen mit einem riesigen Potential. Das molekulare Netz, das die Regulation und Transduktion von Signalen in Einzellern realisiert, ist vergleichbar mit den Prozessen innerhalb eines Nervennetzes. Eine Population von einzelligen Organismen kann als individuelles, multizelluläres Netz mit erhöhtem Erkennungspotential angesehen werden. Schließlich zeigen wir, daß raffinierte Formen von Kooperations- und Konkurrenzverhalten auch in Einzellerpopulationen vorhanden sind. Eine ähnliche Aussage scheint nicht für Phänomene wie Imagination (Probehandeln) und Introspektion möglich zu sein, die auch im Zusammenhang mit der Bewältigung sozialer Probleme zu sehen sind. Eine genaue naturwissenschaftliche Erfassung solcher Aspekte, die erst einen Vergleich zwischen Mehrzellern und Einzellern erlauben würde, ist allerdings noch zu leisten.  相似文献   
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