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991.
Three experiments examining the information extraction processes are presented. In Experiments I and II, adults and children were presented paragraphs to read and search for specified targets, respectively. Two types of typographical (spatial) manipulations were used: case of the letters within the paragraphs was as normally experienced, or in alternating upper and lower case letters. Spacing between words was either as normal, filled with a neutral symbol, or absent. The response measures were reading and search speed in words per minute. Sensitivity to case (word shape) and space (word boundary) increased as a function of experience and was different for reading compared with search. In Experiment III subjects were asked to judge whether briefly presented pairs of letters were the same or different. Retinal (spatial) location was varied from trial to trial; dependent measure was reaction time. Results showed a developmental progression in response time with complex interactions. Theoretical interpretations of these data are discussed in support of the initial stage of Hochberg's peripheral to cognitive search guidance model.  相似文献   
992.
Token-mediated access to play and snacks was made contingent on completion of academic tasks in the Baseline Experiment. This contingency produced stable completion rates that were subsequently doubled, and then tripled, for four deviant children in a special preschool. A reversal design demonstrated that the contingency was functional in maintaining the children's rates of task completion. The Guidance Experiment examined the role of a social event, teacher guidance, in the acquisition of task-completion skills, in a multiple-baseline-across-tasks design (with reversals). The analysis demonstrated that teacher guidance was an important supplement to the token-mediated contingency in establishing significant increases in task completions for a second group of three deviant children in the special class. The importance of teacher guidance was related to the difficulty level of the children's tasks.  相似文献   
993.
Retardate use of retention strategies and the independence of color and form retention were compared with predictions of the Attention-Retention theory of retardate discrimination learning. Lists of two-choice discrimination problems were increased in length from one to capacity, which was defined through criterion retention across a 20-sec interval. It was demonstrated that (a) capacity and rate of adjustment of retentional strategy were directly related to intelligence, (b) at capacity limits the retention of problems in one dimension interfered with retention in a second dimension, and (c) results consistent with a capacity allocation strategy were obtained. The results were interpreted as reflecting short-term memory capacity constraints on the use of rehearsal.  相似文献   
994.
Human infants' discrimination of changes in internal and external elements of compound visual patterns was investigated in four experiments employing a familiarization-novelty paradigm in which visual reinforcing patterns were presented contingent upon rate of high-amplitude nonnutritive sucking. In Experiment 1, 4-month infants discriminated changes in the shape of internal, external and both internal and external figures. One-month infants discriminated external changes in both internal and external figures, but failed to show reliable response recovery when only internal figures were changed. Experiments 2 and 3 failed to explain the 1-month results on the basis of poor resolution of internal figures by showing comparable discrimination of small and large singly-presented figures and by failing to find improved internal discrimination with large separation between internal and external figures. In Experiment 4, 1-month infants showed response recovery to figure additions made adjacent to the initial figure, but not to internal additions. The results are interpreted in terms of attentiveness by young infants to external pattern elements and may indicate early processing of figure-ground information. The developmental differences observed suggest an increased breadth of attention to pattern elements.  相似文献   
995.
To assess the development of monocular slant perception as well as the relative effectiveness of different sources of information, children in first, third, and fifth grades and college adults were asked to make judgments of surface slant on the basis of monocular texture gradient information. Accuracy of judgment increased with increasing age. In addition, differences in gradient effectiveness were found. Compression gradients were relatively ineffective sources of information, whereas perspective and multiple gradients resulted in greater accuracy. The results suggest limitations on the specificity of certain forms of gradients.  相似文献   
996.
A total of 400 children at ages 5, 9, and 12 years were given a component selection task with stimuli differing in color and shape. Relative salience of these two stimulus components was manipulated across subjects in two ways: the standard shapes and colors from previous studies were compared with standard shapes in fluorescent colors, and the latter materials were compared with nonsense shapes in fluorescent colors. While fluorescence of color had little effect, the replacement of standard shapes with nonsense figures caused attention to be redirected from shape to color as the primary cue for learning. This effect was more pronounced at age 9 than at age 5. Apparently there is a greater tendency for older than for younger children to withdraw attention from a normally dominant component such as shape, when it is advantageous to adopt another feature such as color as the primary functional cue. An additional variable was integration of components (color within shape vs color as background for shape). Integration produced generally greater attention to color but did not affect the general pattern of salience effects.  相似文献   
997.
This study investigated the effects of arranging task events for interdependence, to increase the probability of social responding. During task interdependence, the subjects, participating in dyads and a four-person group, obtained task materials (a puzzle piece) from their partner before completing their task (appropriately placing the puzzle piece). The verbal contingency required a verbal request to precede a subject's receiving a task material from his partner. The verbal contingency yoked with task interdependence made task completion contingent on the appropriate verbalization. The findings from two experiments suggested that task interdependence was sufficient to increase partner-directed verbalizations for three of the four subjects. When the verbal contingency was added, all subjects increased their requests and other verbalizations to partner. Applied to a four-person group, the verbal contingency yoked with varying levels of task interdependence correspondingly affected the pattern and level of group communications. The greater the task interdependence, i.e., the more members each subject depended on to complete his task, the more complex the social network of verbal contacts, and the higher the level of both requests and other verbalizations for the group.  相似文献   
998.
Five parents of nonverbal children were trained in two home settings to modify antecedents and consequences to their children's vocalizations. Generalization effects of the parent training on both the parent's and children's behaviors under different stimulus conditions were investigated using multiple-baseline designs. Increases in parent prompting and reinforcing their children's vocalizations generalized only minimally to a new setting in the home where parent training had not occurred. Child increases in vocalizations produced by the parents in the training settings did generalize to this new setting in the home. There was minimal generalization of child vocalizations to a free-play setting at school. In a formal speech session conducted by a behavior specialist at school, only one child showed definite increases in acquisition rate as a function of the parents starting to train the sound at home.  相似文献   
999.
Undergraduate students had been assigned to a contingency managed course or a conventional lecture course (Du Nann and Fernald, Journal of Applied Behavior Analysis, 1976, 9 , 373–374). Two years later, some 35% (N = 86) of the original classes responded to a letter offering them $2.00 to participate in a study of their educational experiences. These students completed a multiple-choice test on material from the course, and answered questions about activities and attitudes that might have been affected by the experience in Introductory Psychology. In the contingency management course 2 yr past, students were tested each week on a chapter of textbook material with 10-item multiple-choice quizzes. The course employed a modified “Doomsday Contingency”, requiring each student to achieve 80% mastery on one of the four weekly quizzes or drop the course. Quizzes were given in small groups and scored individually, while the student stood near, by an undergraduate proctor assigned to that group. The proctor was asked to show interest in the students' quiz performances, help clear up difficult areas, and develop a friendly working relationship with each student. While many students passed the quiz on the first attempt, others were given individual tutoring, so that no one was in fact forced to drop the course. In addition to the weekly quiz assignment, students in the contingency managed group were asked to attend one lecture each week. While the contingency management course procedures had much in common with PSI (Keller, Journal of Applied Behavior Analysis, 1968, 1 , 79–89), several departures made them unique. First, self-pacing was curtailed because students were required to master one unit per week or drop the course. Second, proctors met with students in small groups, usually giving individual tutoring only to those students who did not pass the quiz on the first attempt. Finally, students were asked to attend one lecture per week. Students in the conventional lecture group were not asked to pass weekly quizzes, but instead attended three 50-min lectures each week. Two of these lectures followed the textbook material closely, while the third, which was also attended by students from the contingency management course, covered material only indirectly related to the text. This partition of lecture content allowed material to be similar across the two instructional groups. Although students in the lecture condition were told they could obtain copies of the quizzes, few of them did so. Course grades were determined by scores on two 45-item multiple-choice hourly exams, each covering half the semester material (each worth 25%), and by a 90-item final exam, which served as a measure of short-term retention. Before analyzing the follow-up data, several characteristics of the returning students were compared to determine the comparability of the sample from the two original classes. Most important, both attrition and the current mean GPAs of students from the two classes were very similar. These considerations, and others, suggested there was no systematic sampling bias to confound comparisons of student performance. A 2 (contingency management versus traditional lecture) by 3 (high, medium, and low GPA) analysis of variance was computed on the course final-exam scores and the follow-up measures. Instructional procedure and GPA interacted on the final exam such that low and medium GPA students performed significantly better under contingency management, but there was no significant effect of instructional procedure with high GPA students. On the 2-yr retention measures, students from the contingency management course performed significantly (p < 0.01) better on items drawn from quizzes used in their original course, and marginally better (p < 0.10) on items drawn from the final exams, but no interactions with GPA appeared. Furthermore, instructional method produced no significant main effects or interaction with how many students became majors or minors in psychology, how many psychology courses were later taken, how many books in psychology were reported to have been read, or on students' evaluation of the interest and importance of psychology.  相似文献   
1000.
Thirty-seven overweight subjects were recruited from the staff of a V. A. Hospital for a weight reduction program. A self-reinforcement (SR) test was administered prior to treatment and subjects were classified as high or low self-reinforcers. Subjects were then exposed to one of two behavioral weight-reduction programs or a minimal treatment control condition. One treatment program emphasized self-control (SC) and the other incorporated a therapist controlled financial contingency for weight loss (EC). A significant interaction was found between SR group and treatment condition. High SR subjects lost weight at the rate of 1.49 pounds per week in the SC condition and only 0.37 pounds per week in EC. Low SR subjects lost at the rate of 1.06 and 1.01 pounds per week respectively in SC and EC. Implications for treatment and future research were discussed. The financial contingency had either neutral or negative effects. Caution was advised for any future use of that procedure.  相似文献   
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