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981.
We examined the effects of behavioral procedures to modify the food choices of preschoolers during a snack period at school (training setting) and at home (generalization setting). In the first experiment, we evaluated the usefulness of nutrition training and a generalization programming strategy of cueing to improve healthy snacking; in the second experiment we investigated the effect of nutrition training alone. In addition, three cases are presented that illustrate individualized procedures to facilitate generalization of healthy snacking to home. Results indicated that children's healthy snack choices increased in the preschool training setting, that generalization to home was achieved only when procedures to program it were implemented, and that the best results were found when the generalization procedures were tailored to the individual child.  相似文献   
982.
Questionnaires concerning attitudes toward use of microcomputers at home, in school, and at video arcades were administered to 879 high school students. Direct observations of adolescent proxemics and sex differences, and of various parameters of video games in 18 video arcades were made. A thorough and representative content analysis of sex bias of microcomputer software advertising brochures was carried out. Results supported previous findings of overrepresentation of masculine culture in the adolescent world of microcomputers, particularly regarding video games. Various types of computer-related activity were not related to socioeconomic class of the parents or to academic grades except for use of home microcomputers, which was mildly positively related to socioeconomic class (r = .124, p less than .001). Nearly half the activity in the arcades was strictly solitary. None of the arcade video games allowed for cooperative play. Most allowed only for sequential competition (86%) or simultaneous competition (7%); as many as 7% did not provide a display of the scores for a second player.  相似文献   
983.
This paper attempts to: (1) provide a paradigm through which to understand the human self and, (2) bring some order out of the variety of theories of personality and strategies of change used in clinical practice today. Drawing on modern physics and general systems theory, a multi-leveled, systemic model incorporating physical, psychological, and spiritual dimensions is proposed and then applied to a representative clinical case. Implications of this model for clinical work and for a spiritual understanding of personality are elaborated.  相似文献   
984.
The Christian has a unique resource for responding to the problem of how competent adults can exercise responsibly the right to control the last stages of their living/dying. Recent natural death legislation offers only a partial solution, because it does not specify what counts as life-sustaining procedures which may be discontinued if the individual fills out a directive to the physician. One of the most troublesome questions continues to be whether the withholding or withdrawal of artificial feeding, or indeed natural feeding, is ever justifiable. An adaptation of principles included in the Christian idea of fasting seems to provide adequate criteria for determining when forgoing nourishment by the terminally ill adult is morally justifiable.  相似文献   
985.
Two experiments were designed to assess whether depriving rats of food would increase the reinforcement effectiveness of wheel running (Experiment 1) and whether satiation for wheel running would decrease the reinforcement effectiveness of food (Experiment 2). In Experiment 1, a progressive-ratio schedule was used to measure the reinforcement effectiveness of wheel running when rats were deprived or not deprived of food. Completion of a fixed number of lever presses released a brake on a running wheel for 60 s, and the response requirement was systematically increased until the rat stopped pressing or until 8 hr had elapsed. The ratio value reached (and the total number of lever presses) was an inverted-U function of food deprivation (percentage body weight). In Experiment 2, when wheel running preceded test sessions, fewer food-reinforced lever presses were maintained by the progressive-ratio schedule, and responding occurred at a lower rate on a variable-interval schedule. An interpretation of these results is that deprivation or satiation with respect to one event (such as food) alters the reinforcement effectiveness of a different event (such as access to wheel running).  相似文献   
986.
It is suggested that molar streams of behavior are constructed of various arrangements of three elementary constituents (elicited, evoked, and emitted response classes). An eight-cell taxonomy is elaborated as a framework for analyzing and synthesizing complex behavioral repertoires based on these functional units. It is proposed that the local force binding functional units into a smoothly articulated kinetic sequence arises from temporally arranged relative response probability relationships. Behavioral integration is thought to reflect the joint influence of the organism's hierarchy of relative response probabilities, fluctuating biological states, and the arrangement of environmental and behavioral events in time.  相似文献   
987.
Relationship between Knapp's metaphor scale of attitudes toward time and subjective estimation of fixed time intervals, measured by a modification of Lovett Doust's method, was described. Results were discussed within the framework of studies relating the measurements of cognitive styles and altered consciousness states to the dilated or accelerated perceptions of time.  相似文献   
988.
In previous studies subjects who have learned a positioning response with kinesthetic feedback tended to make greater errors when visual feedback was provided during later trials. These subjects have always performed with both kinesthetic and visual feedback available. This study determined whether subjects with only visual feedback would produce errors similar to those who received kinesthetic plus visual feedback. Blindfolded subjects learned to move a handle to a criterion location with knowledge of results following each trial. Subjects then were assigned to one of three experimental groups, with only kinesthetic feedback, with kinesthetic plus visual feedback, or with only visual feedback. Subjects had 9 trials without knowledge of results in these feedback conditions. When visual feedback was available, subjects tended to make longer response errors. This finding replicates previous studies. Also, the similarity of performances from the conditions with visual feedback indicated the dominance of visual information in the condition with kinesthetic plus visual feedback.  相似文献   
989.
A match-to-sample task and a preference-ranking procedure were used to provide predifferentiation experiences on a color discrimination for 6- and 8-yr.-old children. The subjects included an educable mentally retarded 8-yr.-old group, an average 8-yr.-old group, a gifted 6-yr.-old group, and an average 6-yr.-old group. Mental age was the best predictor of success on task. A significant interaction of sex and teaching method suggests an advantage of girls in this group in instructional situations in which the perceptual learning task and testing tasks are not exactly the same. Girls did better than boys when a different response for task content was required in testing from that in teaching. Boys and girls performed similarly when the training task was the same as the testing task.  相似文献   
990.
Parieto-occipital EEG alpha was recorded bilaterally, while 20 high- and 20 low-hypnotizable women performed one left-hemisphere and one right-hemisphere task of low difficulty and two other comparable tasks of high difficulty. Every task was performed twice, once with eyes open and once with eyes closed. All subjects were right-handed. The tasks were originally selected to be of high and low difficulty. The subjective rating of task-difficulty was also evaluated. The integrated amplitude alpha and the alpha ratio (R-L/R + L) were the dependent variables. The highly hypnotizable women showed significantly higher alpha amplitude in eyes-closed condition than the low scorers; this difference disappeared during task performance and in the eyes-open condition. The left-tasks showed lower alpha amplitude in both hemispheres than right-tasks and baseline. The right-hemisphere alpha amplitude was lower than left in all experimental conditions. On tasks of high and low difficulty there was different hemispheric behavior on right and left tasks. Performance reflecting the right and left hemispheres in the low-difficulty condition showed no changes between baseline, right- and left-tasks, while under high difficulty there was a decrease in alpha amplitude in the right and even more marked decrease in the left hemisphere during left-tasks. The pattern of task effects for ratio scores was the same as for alpha amplitude, however, despite the analysis of alpha scores, an interaction of hypnotizability X task-difficulty was detected. The highly hypnotizable women showed less negative alpha ratio during a task of low difficulty than during tasks of high difficulty; the reverse was true for the low-hypnotizable women. Finally, the highly hypnotizable subjects showed less subjective difficulty during performance than the low scorers.  相似文献   
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