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131.
Simultaneous prompting (a type of antecedent prompt and test procedure) and constant time delay were compared with four students with moderate mental retardation learning expressive sight words. A parallel treatments design across word sets and replicated across students was used. For acquisition, the simultaneous prompting procedures required fewer trials, sessions, and training time to criterion and resulted in fewer student errors during daily probe and training sessions. However, maintenance data indicated mixed results across the two procedures. Reliability data (both dependent and independent variables) revealed no differences between the two procedures in terms of the teacher's accuracy in recording student responses and implementing each procedure. Future research issues are discussed.  相似文献   
132.
The purpose of this research was to examine the relationship between parents' perceptions of marital satisfaction and family stress and their third grade children's classroom behavior. Twenty-one married couples completed questionnaires during home visits. Behavior observations were made from videotapes of children recorded in their classroom during lunch and group academic periods on each of three days. Frequencies of peer interactions, solitary behaviors, and teacher interactions were coded. Regression analyses showed that mothers' level of marital satisfaction (but not fathers') predicted their children's frequency of peer interactions during lunch. Fathers' level of perceived family stress (but not mothers') predicted their children's frequency of peer interactions during lunch. Neither measure for either parent was related to the frequency of peer interactions, solitary behaviors, or teacher interactions observed during the academic sessions. These findings highlight the importance of assessing the potential differential relation of parent variables to children's trans-situational behaviors, and the examination of these variables in relation to different social-environmental contexts in which children participate outside the home.  相似文献   
133.
Thirsty rats were used in order to determine whether a vinegar solution, which had been paired with an injection of lithium chloride, could block the formation of an association between a pentobarbital- and a lithium chloride-induced state. During phase 1 the rats in the blocking group had a 2.0% vinegar solution paired with an injection of 240 mg/kg of lithium chloride, during phase 2 these rats were reexposed to the vinegar prior to each injection of 20 mg/kg of pentobarbital and 240 mg/kg of lithium chloride, and during phase 3 these rats were given access to a novel 0.75% saccharin solution and were injected with pentobarbital after saccharin removal. Animals with this history did not form an association between the pentobarbital- and lithium chloride-induced states during phase 2 as evidenced by their refusal to consume the saccharin solution over repeated pairings of saccharin with pentobarbital during phase 3. Control groups that received forward pairings of pentobarbital and lithium chloride, in the absence of a previously conditioned vinegar solution during phase 2, formed an association between pentobarbital and lithium chloride. These findings indicate that drug states and flavors can interfere with each others' capacity to predict the occurrence of lithium chloride.  相似文献   
134.
Varieties of size-specific visual selection   总被引:1,自引:0,他引:1  
Compared time to evaluate stimuli of varying sizes. When Ss expect an upcoming stimulus to be a certain size, response time increases with the disparity between expected and actual size. There are, however, 2 size adjustment processes, and they reflect 2 types of visual selection. In the first, a shape-specific image representation is used to separate a visual object from a superimposed distractor. These representations require the type of slow size scaling demonstrated in imagery experiments. The second size scaling process is faster and not shape-specific. At any given time the visual system is set to process information at a particular scale, and that scale can be adjusted to match an object's size. Because both selection mechanisms depend on size, they probably occur at a relatively low, spatially organized processing level. These findings lead to a new explanation for results that had been taken as evidence for attentional selection at the level of object representations.  相似文献   
135.
136.
154 autopsy cases of alcoholics (120 men and 34 women) were investigated from a neuropathological viewpoint. In only 19 cases could typical diseases of the nervous system caused by alcoholism be found (Wernicke's encephalopathy, central pontine myelinolysis, Marchiafava-Bignami's disease and disorders of the peripheral nerves and muscles). In comparison liver diseases occurred almost five times more frequently in our own material. Diseases caused by alcoholism of the nervous system, the question of brain shrinkage and its partial reversibility, the up to now not completely known effects on the neurophil and cortical cytoarchitectonic are discussed according to the literature.  相似文献   
137.
In several studies attributing positive health benefits to running, the benefits include reduced depression, fatigue, anger, and increased vigor. Until now, little research has focused on Masters track and field athletes. The present study reports on 587 men and women Masters who participated in a mailed survey measuring mood states using the Profile of Mood States. In comparison to other groups of athletes, these Masters tend to be less depressed, less angry, and less fatigued. Attribution to lifestyle and maturity with their sport is discussed.  相似文献   
138.
The purpose of this study was to measure subjects' ability to detect deliberate stressed, front-vowel misarticulations embedded in two-syllable words. Reaction times to words with various vowel-height misarticulations were examined for 25 women to assess the effect of a specific vowel height change on listeners' ability to recognize a word. Statistical analysis indicated no significant differences between reaction times to initial, stressed vowel changes along the height dimension, suggesting that subjects responded similarly to all vowel errors on the detection task. This finding provides further evidence that stressed-vowel information may serve as a perceptual anchor in guiding a listener during word recognition.  相似文献   
139.
When a formant transition and the remainder of a syllable are presented to subjects' opposite ears, most subjects perceive two simultaneous sounds: a syllable and a nonspeech chirp. It has been demonstrated that, when the remainder of the syllable (base) is kept unchanged, the identity of the perceived syllable will depend on the kind of transition presented at the opposite ear. This phenomenon, called duplex perception, has been interpreted as the result of the independent operation of two perceptual systems or modes, the phonetic and the auditory mode. In the present experiments, listeners were required to identify and discriminate such duplex syllables. In some conditions, the isolated transition was embedded in a temporal sequence of capturing transitions sent to the same ear. This streaming procedure significantly weakened the contribution of the transition to the perceived phonetic identity of the syllable. It is likely that the sequential integration of the isolated transition into a sequence of capturing transitions affected its fusion with the contralateral base. This finding contrasts with the idea that the auditory and phonetic processes are operating independently of each other. The capturing effect seems to be more consistent with the hypothesis that duplex perception occurs in the presence of conflicting cues for the segregation and the integration of the isolated transition with the base.  相似文献   
140.
The continuous approach to optic-flow processing shows that the curvature of a moving surface is related to a second spatial derivative of the velocity field, the spin variation (Droulez & Cornilleau-Pérès, 1989). With this approach as a theoretical framework, visual sensitivity to the curvature of a cylinder in motion was measured using a task of discrimination between cylindrical and planar patches. The results confirm the predictions suggested by the theory: (1) Sensitivity to curvature was always greater when the cylinder axis and the frontal translation were parallel than when they were orthogonal. The ratio of curvature detection thresholds in the two cases was between 1.3 and 2.5; the value predicted from the spin variation theory is about 2. (2) Sensitivity to curvature increased strongly with the velocity of the motion but was only weakly affected by its amplitude and the duration of viewing for the range of values used in our experiments.  相似文献   
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