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161.
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   
162.
Three experiments investigated the effects of naming pictures of objects during study on the subsequent recognition of physically identical, name-match, and new objects. Prior naming improved correct classification of all three item types at recognition. For line drawings and for photographs of functionally distinct objects, prior naming reduced the tendency to confuse identical and same-name alternatives. In Experiment 2, prior naming eliminated the right visual field/left hemisphere advantage for speeded recognition of name-match pictures, suggesting that prior naming reduces the likelihood that pictures are named at recognition. The implications of these results for dual-encoding (Paivio, 1971) and sensory-semantic (Nelson, Reed, & McEvoy, 1977) models of picture and word processing are discussed. The results suggest that the semantic representations of objects that are perceptually distinct but share a common name are not identical, and that the effect of naming such objects is to insure that a distinct semantic representation becomes a part of the resulting memory code.  相似文献   
163.
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   
164.
165.
Various writers have considered madness to be a religious experience. On the basis of the literature in the area and conversations with psychiatric patients, it is argued that madness as a religious experience can be viewed as a four-stage developmental process. The four stages are: 1) The hurt-and-be-hurt state of being, 2) The self-induced psychedelic experience, 3) The confusion-and-dread reaction, and 4) The reconstruction-with-insight world view. To clarify how these four stages make up a religious experience, the poet Allen Ginsberg's so-called psychotic episode is organized around each of the stages.  相似文献   
166.
Helgesen MW 《America》1979,141(21):426-427
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167.
The technique of Waugh & Norman (1965) is widely used in measuring the capacity of primary memory. Watkins (1974) has proposed a modification of the technique which takes into account registration failure. A further modification is proposed which takes into account findings of negative recency in delayed recall.  相似文献   
168.
The development of taste aversion learning to novel cues contained in mother's milk was examined in rat pups. Pups receiving distinctive mild by experimenter-delivered oral infusions followed by toxicosis formed an aversion to the dam's diet. Robust aversions were learned as early as Day 10 and were retained for at least 11 days. When the same distinctive milk was obtained directly from a foster mother through nursing, however, only weanling-age pups (over 20 days) formed an aversion. X-ray analysis of nipple location in the mouths of suckling pups suggested that pups between the ages of 10 and 21 days receive milk at a similar tongue locus. Flavored milk was then delivered at specific time intervals in controlled quantities through tongue cannulas implanted at loci corresponding to the nipple position shown by the X-rays. Cannulated preweanling pups that were attached to a nipple during milk delivery failed to associate the taste cue with illness, whereas both preweanlings off the nipple and weanlings on the nipple acquired aversions to the taste cue in the milk. The evidence obtained in these experiments suggests that pups of all ages are incapable of expressing a taste aversion in a nursing situation and that preweanling pups in particular are also dificient in acquiring aversions within a suckling context. The inability of preweanling pups to acquire taste aversions in a nursing situation appears to result from a failure to associate taste cues with illness rather than a failure to detect taste cues obtained from a nipple.  相似文献   
169.
Two experiments confirmed sequential mediation of social interaction by investigating the effects of generalized expectancies on specific expectancies and the effects of specific expectancies on performance. Both experiments used a simulated tutoring task in which the subject took the role of tutor while a confederate took the role of student. In Experiment 1 subjects combined generalized expectancies about the effectiveness of certain tutoring responses with specific situational information to produce specific expectancies about the results of the tutoring responses under the experimental circumstances. Experiment 2 replicated this finding and showed that specific expectancies of the relative effectiveness of different responses influenced which response was performed more. Results were discussed in terms of cognitive motivation theory and social learning theory.  相似文献   
170.
This study investigated auditory discrimination as a function of ethnic group membership within the same socioeconomic status (SES). Subjects were 126 randomly selected six-year-old students attending schools in the lower SES community of southeast San Diego. Only students with no known speech or hearing defects and of normal intelligence were included. They were assigned to one of three categories: Black, Chicano, or Anglo.Subjects were administered four tests in a counterbalanced design: the Wepman, the Gross, and the Ott. The latter two were developed for use with Black dialect and Spanish-speaking youngsters, respectively. The ANOVA results indicated a reliable difference between the main effects of the groups (F=40.34,p<.001) and tests (F=72.82, p<.001), with a significant interaction between tests and groups (F=44.91, p<.001). Interaction effects were evaluated with the Dunn theorem. Significant differences were found among Anglo, Black, and Chicano students on the discrimination list for Spanish sounds (Ott) and a significant Anglo/Black difference on the discrimination test for Black dialect (Gross). Contrary to previous findings, there were no differences between the groups on the Wepman Test of Auditory Discrimination (WTAD). However, there are significant differences between groups on separate items of this test.  相似文献   
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