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231.
Although geometric information is altered when a picture’s viewing point is changed, such changes often do not affect perception. Two experiments assessed pictorial perception relative to the distortions introduced by viewing point dislocation. Results provide a psychophysical demonstration of pictorial compensation and suggest that it is based on the discrepancy between the actual and an assumed-correct viewing position. An explanation of pictorial compensation is offered that could be applied to direct picture perception and to picture-in-a-picture perception.  相似文献   
232.
Special difficulties are encountered when attempting to provide intracranial cannulation of small animals that have floating or fragile skull bones. The technique described was developed for mice but seems applicable to other species. The cannula system is inexpensive and easy to use. A wound clip anchor seems superior to either skull screws or bonded acrylic, producing less damage to the brain and no necrosis of bone or tissue on the wound margin. Patency data up to 25 days is presented, and the system is as efficacious as other techniques.  相似文献   
233.
The effect of contextual stimuli on proactive interference in the rat was investigated in three experiments. The task was a modified delayed alternation procedure in which the rat was initially forced to one side of a T maze (the interfering forcing) followed by a forcing to the opposite side (the target forcing). A free choice run followed the target forcing in which a turn in either direction could be made. In order to obtain reinforcement on the free choice run, the rat was required to turn in the direction opposite that of the target forcing (i.e., in the same direction as the interfering forcing). Manipulation of the context prevailing during the interfering forcing, target forcing, and free choice runs revealed that free choice accuracy was (a) greater when the interfering and target forcings were conducted in different contexts than when they were conducted in the same context and (b) influenced only slightly, if at all, by whether the free choice context coincided with that prevailing during the interfering forcing or with that prevailing during the target forcing.  相似文献   
234.
In a pilot study, a multielement design was used to assess the effectiveness of a response cost procedure on a 7-year-old child's hyperactive behavior and academic performance across days. The procedure was effective in reducing off-task behavior and in increasing academic assignment completion. In Experiment 2, three strategies were compared to a no-treatment baseline in treating an 8-year-old hyperactive child: drug (Ritalin) alone, response cost alone, and drug plus response cost. The cost program alone and the cost program combined with medication were effective in reducing off-task behavior and in increasing academic performance. In both studies, the procedure was viewed by the teachers as practical and effective for use in a classroom setting. The subjects liked the cost system and believed that they completed more academic work when it was operative.  相似文献   
235.
The purpose of this study was to compare a non-clinic sample of mothers and children to two groups of clinic-referred children and their mothers. The two clinic-referred groups differed from one another in that the selection criterion for one group of children (Clinic Deviant) was that they were significantly more deviant and non-compliant than the non-clinic group whereas the selection criterion for the second group of children (Clinic Non-deviant) was that they did not differ significantly from the non-clinic group on deviant and non-compliant behavior. Home observations by independent observers and parent questionnaires examining parental adjustment and parental perceptions of child adjustment were completed. The results indicated that both clinic groups perceived their children as more maladjusted than parents in the non-clinic groups perceived their children. Parents of the children in the Clinic Non-deviant group were significantly more depressed than those in the remaining two groups, whereas parents in the Clinic Deviant group issued more vague, interrupted commands than those in the Clinic Non-deviant group. Implications of the findings are discussed.  相似文献   
236.
Behavioral interventions for primary dysmenorrhea are reviewed under four categories: hypnotherapy; Lamaze exercises; biofeedback training; and desensi found in only the last category and even here, the extent to which positive results stem from desensitization-based treatments themselves as opposed to nonspecific factors associated with these treatments is unresolved. Additional issues that bear upon behavioral treatments for primary dysmenorrhea are: (a) the need for further taxonomic refinement; and (b) the need to incorporate pathophysiological findings within the treatment of this disorder.  相似文献   
237.
In 14 experiments, subjects had to “point to” surrounding environmental locations (targets) while imagining themselves in a particular spot facing in various directions (orientations). The spatial information was either committed to memory (cognitive maps) or directly presented on each trial in the visual or tactile modality. Reaction times (RT) indicated that orientation shifts were achieved through mental rotation in the visual task, but not in the cognitive map or tactile tasks. Further, in the latter two tasks targets were located most quickly when they were adjacent to or opposite the imagined orientation. Several explanations of this finding were tested. Various aspects of the data suggest that cognitive maps are not strictly holistic, but consist of orientation-specific representations, and—at least in part—of relational propositions specific to object pairs.  相似文献   
238.
Children of 8 and 11 years were assessed in two experiments for their sensitivity to textual anomaly. In Experiment 1, subjects read stories containing two target lines, one appropriate and the other anomalous in relation to previously given information. Both age groups read the anomalous line more slowly than the appropriate line, but in a subsequent test of comprehension monitoring, the older group was more likely than the younger group to pick out the anomalous line as not fitting in with the rest of the story. Experiment 2 produced similar results: both 8- and 11-year-old children read an anomalous line more slowly, but 11-year-olds were more likely than 8-year-olds to cite the anomalous line or part of it when questioned about the possible presence of a line that did not fit in with the rest of the story. The results indicate that an age change in comprehension monitoring as indexed by citation or selection of a textual anomaly need not be contingent upon a parallel age change in constructive processing as indexed by modulation of reading rate.  相似文献   
239.
240.
The way in which the apparent magnitude of numbers grows with their absolute magnitude was measured with a modified version of the direct technique Marks and Slawson (1966) used to determine the psychophysical exponent for loudness. This modified technique required subjects to estimate how evenly and randomly a sequence of integers appeared to sample the numerical continuum. The results indicate that the apparent magnitude of numbers increases with a decelerated power function of their arithmetic magnitude when a series samples from an open-ended range. However, when an upper boundary of the range is specified, the subjective scale seems to be linear. Random productions of numbers parallel the results found with judgments of presented sequences. The two scales of number provide the basis for an interpretation of the difference between magnitude and category scales: that subjects use numbers differently when the response scale is open-ended Imagnitude estimation than when it has a fixed upper limit tcategory scale. Given the assumption that subjects use numbers in this way in the two tasks, the qualitative relation between magnitude and category scales is predicted.  相似文献   
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