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211.
The acquisition of observing.   总被引:6,自引:6,他引:0       下载免费PDF全文
Pigeons were exposed to stimuli correlated with the presence or absence of a variable-interval 60-second schedule of reinforcement only while they depressed a crossbar or "perch." In the first experiment, the stimuli were different tilts of a line displayed on the key. When the difference in brightness between the line and the background (salience) was maximal, seven of eight birds acquired the discrimination, but when the difference was reduced by 50%, only one succeeded. In the second experiment, wavelength of chamber illumination served as the relevant dimension. Neither experiment showed a large effect attributable to the magnitude of the difference (disparity) between the positive and the negative stimulus. Individual differences in time spent observing were positively correlated with level of discrimination in the presence of the stimuli. All birds produced the positive stimulus for a greater proportion of the available time than they did the negative stimulus. This may be the mechanism that provides selective reinforcement of observing. Finally, the formation of a discrimination was analyzed in terms of changes in the proportion of time spent in contact with the discriminative stimuli.  相似文献   
212.
This paper presents a strategy for pairwise assessment which may be used to evaluate the nature of both prerequisite and transference relations existing among a set of traits. This strategy is appropriate for use both within a confirmatory context, in which an attempt is made to establish the validity of some specified set of relations among traits, as well as within an exploratory context, in which a search is made for unconjectured prerequisite and transference relations existing between pairs of traits. Both uses of this strategy are based on a variety of latent class models which are representative of various possible relational states existing between pairs of traits. Thus, the nature of trait relations may be investigated through the use of statistical assessments of both absolute and relative fit attained by these models. An application is presented to exemplify how this strategy may be used within the exploratory context.The author is obliged to Clifford Clogg, C. Mitchell, Dayton, and William Schafer for helpful comments made regarding a previous draft of this paper as well as to Mary Papageorgiou who provided access to the data which was considered in this study.  相似文献   
213.
214.
Within the last few years, considerable attention has been devoted to the possibility that the amelioration of stuttering in many novel speaking conditions is a function of vocal changes with or without accompanying modifications in prosodic expression. These formulations have made reference primarily to conditions in which stutterers were induced into one or another novel speech pattern by an external stimulus such as masking noise, a rhythmic cue, or by instructions to sing, or read in unison with another speaker. In contrast, far less attention has been paid to other ameliorative conditions that lack a novel external stimulus or special instructions that direct the stutterer to speak in some unique manner. Speaking or reading to a child is an example of this latter type of condition. The present study was conducted to see if nine adult stutterers and a matched group of nonstutterers would evince vocal changes as they read aloud to another adult, a child, and a child and adult together. There was also a fourth control condition wherein the subjects read to one of the experimenters. Dependent measures of disfluency and stuttering, fundamental frequency, fundamental frequency deviation, fluent reading rate, and peak vocal sound pressure level were made and treated statistically. The major findings of this study indicated that, relative to the control condition, both subject groups exhibited several vocal changes when reading to a child alone and to a child and adult together. In addition, the stutterers experienced a reduction in disfluency, but only when reading to the child alone. The normal speakers exhibited too few disfluencies in the control condition for any meaningful change to occur in that dependent variable. The fact that the stutterers evinced vocal changes in both experimental conditions but a significant drop in disfluency in just one bears importantly on hypotheses that emphasize vocal changes in conditions that ameliorate stuttering.  相似文献   
215.
Language functioning in Alzheimer's disease is reviewed and the performance of 25 Alzheimer patients on a standard battery is reported. All these hospitalized patients were aphasic to some degree. As a group, they differed from normals on all language variables, and from stroke patients in terms of higher fluency and lower comprehension. Spontaneous speech showed high incidence of circumlocutions and semantic jargon, but no phonemic paraphasias or target approximations. Syllabic perseverations, shouting, inappropriate laughter, and mutism were late-appearing features. Transcortical Sensory, and Wernicke's aphasias were frequent, but Broca's and Transcortical Motor aphasias notably absent. Extent of language impairment correlated with current length of hospitalization but not age. Reading, writing, and performance scores except praxis, were lower than oral language scores. Findings were discussed in relation to previous results, methodology, and language organization in the brain.  相似文献   
216.
This article proposes a model that integrates various factors influencing early childhood stuttering. The factors interact in a synergistic manner and can be subsumed under three macrofactors: physiological, psycholinguistic, and psychosocial. Such a model can be clinically applied toward an integrated approach to the assessment and treatment of the young stutterer.  相似文献   
217.
Bloodstein recently wrote that “the most vital part of science is not accurate measurement or the insistence on empiricism. It is an attitude of inquiry into the how and why of things” [Bloodstein, O. Foreword. In: Maintenance of Fluency (E. Boberg ed.). New York: Elsevier, 1981, p. vii]. In the paper below, I present some unsubstantiated and no doubt controversial thoughts on the how and why of relapse in stuttering. The overall thrust of these thoughts is that stutterers have different propensities to stutter because of the inherent variability in their speech production systems. For this reason, for therapy to have long-range success, stutterers must learn to accept and deal with the inherent variability in their speech production mechanisms.  相似文献   
218.
Twelve children with early intense reading and superior word recognition skills coupled with disordered language and cognitive behavior are described. Cognitive, linguistic, and reading measures evidenced a generalized cognitive deficit in forming superordinate schemata which was not specific to visual or auditory modalities. Positive family histories for reading problems were present for 11 of the 12 children, suggesting a relationship between hyperlexia and dyslexia.  相似文献   
219.
The development of a test to measure Elli's concept of rationality is described. In the first study discussed, a 58-item test is developed to measure rationality, and the reliability and convergent validity of the test is described. In a second study, the discriminant validity of the test is examined. An attempt is also made to reduce social-desirability content in the test by eliminating items most highly correlated with a Social Desirability Scale. The final 44-item test is found to be high in both reliability and validity. The factor structure of the test is also examined.  相似文献   
220.
The purpose of the present study was to evaluate the effectiveness of an intervention program designed to train preschool children in interpersonal problem solving skills. Forty preschool age children were randomly assigned to an experimental or control group. Experimental subjects were trained in interpersonal problem solving skills for ten weeks, four days per week, for a total of 10–13 hours. Problem-solving skills were assessed at pretest, posttest, and three months after training was completed. Seventy-eight percent of the children who participated in pretest and posttest were tested at follow-up. Results indicated that the experimental group, compared to the control group, showed a significant increase in both cognitive—verbal and behavioral interpersonal problem-solving skills from pretest to posttest and that these changes were maintained at follow-up testing. Discussion focuses on suggestions for future research and implications for applied settings.  相似文献   
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