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101.
Meryl J. Wall C. Woodruff Starkweather Helen S. Cairns 《Journal of Fluency Disorders》1981,6(4):283-298
This study examined the location and rate of stuttering in the spontaneous speech of nine young stutterers (4.0–6.6 yr) in relation to certain aspects of syntax. It was designed to answer the following questions: Is there more stuttering at clause onset (boundary) than at other points in the clause? Does the type of clause influence rate of stuttering? Is there more stuttering on complex than on simple sentences? The syntactic analysis defined 10 clause types (seven pertaining to complex sentences and three pertaining to simple sentences); clause boundaries (taking into account “filler” words occuring in such positions); and hierarchical constituent structure within sentences. Stuttering was found with significantly greater frequency at clause boundaries than at internal (nonboundary) positions of clauses. This was apparent for nine of the 10 clause types, the exception being complement clauses. The word “and” at the beginning of simple and complex sentences provoked a high rate of stuttering. The hierarchical structure within the clause did not influence the location of stuttering, and sentence complexity was not a factor in the rate of stuttering. 相似文献
102.
D. G. Williams 《Personality and individual differences》1981,2(4):303-309
The scores of 33 subjects of the neuroticism scale of the Eysenck Personality Questionnaire correlated more highly with mood levels averaged over the 12 occasions studied than, on average, with mood scores on single occasions, and more highly with mood described in global terms than with scores on each of the original 18 mood scales. Subjects with high neuroticism scores had poorer mood on average and showed greater variation in mood pattern from one occasion to another than did more stable subjects. It is suggested that forms of relatively poor mood may be more varied than forms of good mood, and that, although neuroticism makes a poor mood more likely, the precise composition of this mood on any occasion may be determined by the combination of situation characteristics and person variables. Psychoticism scores correlated significantly, though weakly, with the average scores for some mood scales independently of neuroticism. 相似文献
103.
The following schedule of reinforcement as a fundamental determinant of steady state contrast in multiple schedules 总被引:5,自引:5,他引:0 下载免费PDF全文
Williams BA 《Journal of the experimental analysis of behavior》1981,35(3):293-310
Two experiments investigated whether steady-state interactions in multiple schedules depend exclusively on the following schedule of reinforcement. Experiment 1 used a four-component multiple schedule in which two components were associated with the same constant schedule of reinforcement, and where rate of reinforcement was varied in the component that followed one of these. Contrast effects were reliable only in the component that preceded the point of reinforcement variation, although some contrast did occur otherwise. In those instances where contrast other than the following-schedule effect did occur, it was accounted for by the effect of the preceding schedule, an effect for which there were consistent individual differences among subjects, and which varied with component duration. Experiment 2 used a three-component schedule, in which reinforcement rate was varied in the middle component. The results were consistent with Experiment 1, as the following-schedule effect was the only consistent effect that occurred, although an effect of the preceding schedule did occur for some subjects under some conditions, and was especially evident early in training. The conclusion from both experiments is that there is no general effect of relative rate of reinforcement apart from the sum of the effects of the preceding and following schedules, and that the following-schedule effect is the fundamental cause of steady-state interactions. 相似文献
104.
Many basic psychophysical functions offer promise as clinical tests of vision. Here, we discuss problems that one encounters in the clinical setting, how one identifies a psychophysical test for potential clinical development, and an orderly approach to development of suitable test paradigms. Parameters are selected which are relatively insensitive to variables encountered in the field (clinic) in a normal population, but which are sensitive to changes in the response system being studied. Initial data on two hyperacuity tests are presented. These tests are adaptations of hyperacuity paradigms (Westheimer, 1979) to a clinical environment. This particular test set offers promise because it exhibits a unique threshold which is dependent upon neural data processing and is relatively independent of retinal image degradation. 相似文献
105.
A method for identifying eggs laid by different subsections or individual members of groups of domestic hens is described. Fat-soluble dyes are placed in gelatin capsules and fed to selected birds. These dyes produce discrete colored bands in the yolks of eggs laid by those birds. The presence of dye in eggs can be detected through the shell, and different patterns of rings can be distinguished by boiling and sectioning eggs. Application of the method to other species and other circumstances is considered. 相似文献
106.
Multiple role juggling and daily mood states in working mothers: an experience sampling study 总被引:2,自引:0,他引:2
K J Williams J Suls G M Alliger S M Learner C K Wan 《The Journal of applied psychology》1991,76(5):664-674
The effects of multiple role juggling (i.e., simultaneously attending to demands of different roles) on daily mood states of employed mothers were examined. Ss completed activity and mood questionnaires 8 times a day for 8 days. Multiple role juggling had immediate negative effects on task enjoyment and mood. However, contrast effects and habituation to role juggling occurred when mood and satisfaction were examined over time. Furthermore, mood states tended to spill over from one episode to the next within a day, but contrast effects were found across days. These results reflect the complex nature of psychological adjustment to multiple role occupancy. 相似文献
107.
B A Williams 《Journal of the experimental analysis of behavior》1991,56(3):455-473
Rats were trained on a discrete-trial probability learning task. In Experiment 1, the molar reinforcement probabilities for the two response alternatives were equal, and the local contingencies of reinforcement differentially reinforced a win-stay, lose-shift response pattern. The win-stay portion was learned substantially more easily and appeared from the outset of training, suggesting that its occurrence did not depend upon discrimination of the local contingencies but rather only upon simple strengthening effects of individual reinforcements. Control by both types of local contingencies decreased with increases in the intertrial interval, although some control remained with intertrial intervals as long as 30 s. In Experiment 2, the local contingencies always favored win-shift and lose-shift response patterns but were asymmetrical for the two responses, causing the molar reinforcement rates for the two responses to differ. Some learning of the alternation pattern occurred with short intertrial intervals, although win-stay behavior occurred for some subjects. The local reinforcement contingencies were discriminated poorly with longer intertrial intervals. In the absence of control by the local contingencies, choice proportion was determined by the molar contingencies, as indicated by high exponent values for the generalized matching law with long intertrial intervals, and lower values with short intertrial intervals. The results show that when molar contingencies of reinforcement and local contingencies are in opposition, both may have independent roles. Control by molar contingencies cannot generally be explained by local contingencies. 相似文献
108.
109.
Experimentally induced failure sometimes produces helplessness and sometimes facilitation on subsequent tasks. A model which accounts for this in terms of variations in perceived task difficulty and importance and variations in the cost of effort is proposed. Predictions from the model were confirmed in two experiments using the finger shuttlebox. When subjects expected the test task to be easy, importance of test outcome did not affect performance. However, when they expected the test task to be difficult, low outcome importance led to debilitation, and high importance to facilitation. If, in this condition, subjects experienced initial failure on the task perceived as difficult and important, helplessness rather than facilitation was observed. The model proposed may account for some of the conflicting results obtained in laboratory studies of human helplessness. 相似文献
110.
Thirty-six 3- and 4-year-old children were given a battery of six metalinguistic tasks and two measures of language development: the Peabody Picture Vocabulary Test and a sentence comprehension test. The results clearly showed that the majority of preschoolers were able to make at least some metalinguistic judgments, and that metalinguistic performance improved with age. Furthermore, overall performance on the metalinguistic tasks was significantly correlated with each language measure when the effects of age were partialed out. In contrast, the correlation between age and metalinguistic performance was not significant once the effects of both language measures were partialed out. These data demonstrate that preschoolers' metalinguistic abilities are more extensive than has been previously acknowledged, and that they are closely tied to other aspects of language development at this time. 相似文献