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291.
292.
293.
If rats are overtrained on a visual discrimination they generally learn the reversal of the discrimination faster than non-overtrained rats. In position discriminations, however, this effect does not generally hold—indeed several investigators have found overtraining to retard position reversal. One of the important differences between the two types of problem seems to be the presence of irrelevant cues in visual discriminations, and their absence in position discriminations. It is suggested that a second important feature of position discriminations is that overtraining usually causes control of the maze running habit to be transferred from external to proprioceptive stimuli, and that successful reversal cannot normally occur until external control is re-established. In two experiments a study by Krechevsky and Honzik (1932) is repeated with certain modifications, with results that support this hypothesis; and a third experiment provides direct evidence of transfer to proprioceptive control in a T-maze. It is shown that this analysis will explain the apparently conflicting results of all recent position reversal experiments. 相似文献
294.
Previous training studies of fluid intellectual abilities have involved training on either figural relations or induction tasks. In the present study, young, middle-aged, and elderly adults were given training on another measure of fluid ability--Raven's Progressive Matrices. The training involved a strategy-modeling technique that lasted no more than a few minutes. The results indicated that (a) performance on the Raven decreased with increasing age, (b) training significantly improved performance, and (c) the effect of training did not differ as a function of the age or sex of the subjects. Thus, the results indicate that performance on the Raven can be significantly improved in a single, brief training session. 相似文献
295.
Systematic 24-hr behavioral observations of sleep and wakefulness in a skilled-care nursing facility
Sleep patterns of aged, infirm, demented, chronically institutionalized residents of a skilled-care nursing facility were studied. The purpose of this naturalistic study was to describe sleep and wakefulness (S/W) within the limits afforded by brief behavioral observations and to examine homeostasis and diurnal rhythmicity of S/W as a function of psychoactive drug intake. Observers noted S/W every 15 min, 24 hr a day for 10 days in 24 Ss. Results indicated substantial individual variation in daytime hours. Daily and weekly variation within Ss was minimal. Sleep was least likely near sunset. Ss on psychoactive drugs showed dampened diurnal variation in S/W rhythms. In Ss not on such drugs, there was a suggestion of homeostasis of S/W between sleep during the morning and evening hours. Results are discussed methodologically (viability of approach), theoretically (age-related change in sleep), and practically (potential treatments). 相似文献
296.
Teaching the Use of Cost-Benefit Reasoning in Everyday Life 总被引:1,自引:0,他引:1
297.
Kimary N. Shahin 《Argumentation》1990,4(3):347-361
Problems with regard to the analysis of argumentative partly discourse arise from definitorial disconformity. In this article, Informal argument is taken as the primary definition to study the basic structure of argument from a fragment of an Agatha Christie novel. Bilmes' account of the notions of Formulation (F) and Decision (D+/D-) are adapted to describe the relations of opposition which are displayed in informal argument. The minimal structure of argument is represented by the formula F/D-/D-, in which F is a speaker's personal composition of a fact, the first D- is the disconfirming uptake of it by another speaker and the second D- is the completing disconfirming uptake by the initial speaker. Some of the speaker's possibilities to initiate an argument by expressing a Formulation are explored, as well as the social and cultural norms which play a role in argument-initiation and the concepts of win and loss. 相似文献
298.
The orienting response (OR) is a specific behavioral act directed towards extraction of information from the environment. Head and eye movements represent only the tip of the iceberg of internal responses, which includes vascular modifications, EEG changes, and event-related potentials. Two mechanisms of the OR have to be differentiated: voluntary and involuntary. In the event-related potential, such a differentiation is expressed in mismatch negativity (involuntary effect) and processing negativity (voluntary effect). Single unit studies have shown that hippocampal neurones are simulating specific features of the OR as a response to novelty. Repeated presentation of stimuli results in a selective habituation of novelty detectors in hippocampus and of the OR. The trace of a standard stimulus formed at the level of hippocampal neurones matches the features of the standard stimulus and can be called a “neuronal model of the stimulus.” The OR is triggered by mismatch between the test stimulus and the elaborated neuronal model, and is activated by verbal instruction, by reinforcement during the initial stage of conditioned reflex elaboration, and by differentiation of signal and non-signal stimuli. A promising new area of practical application of the OR lies in the evaluation of a corridor of optimal functional state for efficient computer-based learning. Registration of the OR and defensive responses can be used for an objective evaluation of the functional state of the student, or, in a wider sense, of the industrial operator. New avenues of OR research are opened by recent techniques that isolate single-trial event related potentials, and their correlation with autonomic and behavioral manifestations of the OR. The combination of single unit recording with such isolated event related potentials can elucidate the neuronal basis of OR generation. Intracellular recording combined with dye injection can be used for analysis of the synaptic contacts involved in generation of the OR. Integration of macro and micro levels of OR organization can be achieved in a computerized model that can be used for simulation and planning of experiments. A step-by-step improvement of the model will accumulate knowledge about the OR as an important mechanism of information processing. 相似文献
299.
Larrick Richard P. Nisbett Richard E. Morgan James N. 《Organizational behavior and human decision processes》1993,56(3)
We find three factors to be associated with use of cost-benefit rules in everyday decisions. These are effectiveness in achieving desirable life outcomes, intelligence, and training in economics. We argue that these empirical findings support the claim that cost-benefit reasoning is normative. 相似文献
300.
Recommendations for improving consultation research include (a) strengthening consultation analogue research by incorporating “boundary” conditions into research designs and (b) extending the outcome measures used. 相似文献