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961.
In the behavior systems view, a long CS–US interval should differentially condition a general search mode and related behavior, while a short CS–US interval should differentially condition a focal search mode and related behavior. Two experiments paired a long or a short CS with food, and then, during an extinction test, compounded the CS with an unconditioned probe-stimulus of a rolling ball-bearing. Presuming that the long CS differentially conditions a general search mode, and that unconditioned contact of a moving stimulus is characteristic of that mode, presentation of the long CS should facilitate interaction with the ball-bearing. Similarly, presuming that a short CS differentially conditions a focal search mode, and that feeder-directed responses are characteristic of this mode, presentation of a short CS should facilitate nosing in the food-tray. Consistent with these predictions, ball-bearing contact increased in rats receiving the long CS, while nosing in the food-tray was higher with the short CS.  相似文献   
962.
This paper discusses two forms of separability of item and person parameters in the context of response time (RT) models. The first is separate sufficiency: the existence of sufficient statistics for the item (person) parameters that do not depend on the person (item) parameters. The second is ranking independence: the likelihood of the item (person) ranking with respect to RTs does not depend on the person (item) parameters. For each form a theorem stating sufficient conditions, is proved. The two forms of separability are shown to include several (special cases of) models from psychometric and biometric literature. Ranking independence imposes no restrictions on the general distribution form, but on its parametrization. An estimation procedure based upon ranks and pseudolikelihood theory is discussed, as well as the relation of ranking independence to the concept of double monotonicity.I am indebted to Wim van der Linden for bringing Thissen's (1983) paper to my notice, and to Martijn Berger, Frans Tan, and the anonymous reviewers for their constructive comments on earlier drafts of this paper.  相似文献   
963.
Davidson's explanation of first-person authority in utterance of sentences of the form 'I V that p ' derives first-person authority from the requirements of interpretation of speech. His account is committed to the view that utterance sentences are truth-bearers, that believing that p is a matter of holding true an utterance sentence, and that a speaker's knowledge of what he means gives him knowledge of what belief he expresses by his utterance. These claims are here faulted. His explanation of first-person authority by reference to the requirements of interpretability is committed to the view that all understanding involves interpretation. This is argued to be a misconception of understanding and of speaker's meaning. Davidson's account involves acceptance of the cognitive assumption that normally when a person V s that p , he knows that he does. This assumption is challenged. Throughout, Davidson's conception is compared and contrasted with Wittgenstein's.  相似文献   
964.
In a replication of a quasi-experiment by Skarlicki and Latham (1996), we investigated the effect of training union leaders ( N = 25) in the administration of organizational justice principles on union members' ( N = 177) perceptions of their leaders' fairness and the members' subsequent citizenship behavior toward their union. Despite the fact that the union members were also shareholders of the company, the results were replicated. Union leader training increased members' perceptions of their leaders' fairness as well as union members' citizenship behavior directed both toward the union as an organization (OCBO) and fellow union members (OCBI). Organizational justice was found to partially mediate the effect of the training on OCBO, but not OCBI.  相似文献   
965.
Receiver-operating characteristics (ROCs) were examined in three recognition memory experiments. ROCs for item information (i.e., was this word presented?) were found to be curvilinear. However, ROCs for associative information (i.e., were these two words presented together?) were found to be linear. The results are in agreement with the predictions of a dual-process model that assumes that recognition judgments are -based on familiarity and recollection. Familiarity reflects the assessment of a continuous strength dimension and is well described as a signal detection process, whereas recollection reflects the retrieval of qualitative information about the study episode and behaves like a discrete threshold process. The results showed that memory judgments about items relied on a combination of recollection and familiarity, but that judgments about associations relied primarily on recollection. Further examination of the associative ROCs suggested that subjects were able to recollect that old pairs of items were in the study list, and, under some conditions, that new pairs were not in the study list.  相似文献   
966.
Hartman and Hasher (1991) used a garden-path task in which younger and older adults generated the final word for each of a series of high-cloze sentences. Under instructions to remember the final word, the experiment included critical sentences for which the generated word was replaced by a new, to-be-remembered target. Using an implicit priming task, the first experiment replicated a basic finding: Younger adults showed priming only for the target words, whereas older adults showed priming for both the generated and target words. Two experiments explored boundary conditions. One showed that an additional sentence that interpreted the new target word enabled older adults to narrow access to only the target word. The provision of additional time following the introduction of the new target word did not. Specific information, not more time, is required for inefficient inhibitory mechanisms to clear the recent past from memory.  相似文献   
967.
In the area of child psychosocial intervention research, substantial progress in addressing challenging methodological issues has been made. In this article we suggest that continued movement forward requires maintaining a balance between methodological and theoretical issues, and that it would be advantageous to begin to think about matching advances in methodological sophistication by similar advances in theoretical sophistication. The need to advance our understanding of theoretical issues is especially important in light of the challenges raised by postmodernism, particularly as these challenges relate to knowledge development. We discuss these challenges and describe how a pragmatic orientation may be a useful way to respond to them. We also describe how a pragmatic orientation has been useful in our work in developing, implementing and evaluating psychosocial interventions for children with phobic and anxiety disorders.  相似文献   
968.
The ability to compensate for fixation of the jaw by a bite block was investigated in 6 nonfluent aphasics, 6 fluent aphasics, and 10 normal control subjects. Acoustic analyses of the vowels [i u a æ] and fricatives [s s] revealed substantial but incomplete compensation for the perturbation in all three subject groups. Perceptual identification scores and quality ratings by naive and phonetically trained listeners indicated poorer identification of the high vowels [i u] under compensatory conditions relative to normal production. Of particular interest was the fact that all three groups of subjects exhibited similar patterns of results. The findings suggest that any deficit in speech motor programming demonstrated by the nonfluent aphasic patients did not affect compensatory abilities. Results are discussed with respect to normal speech adaptation skills and the nature of articulatory breakdown in nonfluent aphasia.  相似文献   
969.
The purpose of the present study was to develop the Toddler Behavior Screening Inventory (TBSI) for rapidly assessing maternal reports of toddler behavior problems. The TBSI is a 40-item measure intended for use by pediatricians, psychologists, and other child-care professionals. A group of mothers (n = 312) rated the initial 93-item TBSI in terms of behavior frequency and parental perception of the behavior as problematic. Following item elimination, 40 items were retained due to being both frequent and problematic at all toddler age levels. Data were obtained with a new sample of mothers (n = 581) and showed the TBSI to possess good reliability and validity.  相似文献   
970.
The hippocampus, which is critically involved in learning and memory processes, is known to be a target for the neuromodulatory actions of steroid hormones produced by the adrenal glands and gonads. Much of the work of B.S. McEwen and collaborators has focused on the role of glucocorticosteroids and estrogen in modulating hippocampal plasticity and functions. In addition to hormones derived from the endocrine glands, cells in the hippocampus may be exposed to locally synthesized neurosteroids, including pregnenolone, dehydroepiandrosterone and their sulfated esters as well as progesterone and its reduced metabolites. In contrast to hormones derived from the circulation, neurosteroids have paracrine and/or autocrine activities. In the hippocampus, they have been shown to have trophic effects on neurons and glial cells and to modulate the activity of a variety of neurotransmitter receptors and ion channels, including type A gamma-aminobutyric acid, N-methyl-D-aspartate and sigma receptors and N- and L-type Ca2+ channels. There is accumulating evidence that some neurosteroids, in particular pregnenolone sulfate, have strong influences on learning and memory processes, most likely by regulating neurotransmission in the hippocampus. However, the hippocampus is not the only target for the mnesic effects of neurosteroids. Associated brain regions, the basal nuclei of the forebrain and the amygdaloid complex, are also involved. Some neurosteroids may thus be beneficial for treating age- or disease-related cognitive impairments.  相似文献   
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