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911.
Experimental approaches require researchers in a variety of applied business disciplines to design experimental materials. This research is often busy and difficult to secure high-level professionals; thus, researchers must ensure sufficient attention to experimental materials to provide usable data. The current study suggests an experimental design feature to encourage participants to thoroughly process information contained in experimental materials. Based on Reynolds' (1992) selective attention strategy (SAS) model, variations in presentation format were expected to influence the relative salience of information presented. Two aspects of presentation format were manipulated to increase salience: display (paragraph vs. bullet point) and typeface (standard vs. bold underlined). Results indicate display improved ability to retrieve information, but typeface did not. Implications for the design of experimental materials are discussed.  相似文献   
912.
In earlier experiments using interactive computer animation with healthy subjects, it was found that displaying compulsive-like repeated checking behavior affects memory. That is, checking does not alter actual memory accuracy, but it does affect 'meta-memory': as checking continues, recollections are experienced as less vivid and less detailed while confidence in memory is undermined. This procedure provides a model of OCD checking and suggests that checking is a counterproductive strategy to reduce memory distrust. The present experiment was carried out to specify the phenomenological quality of memory distrust after checking and to see if repeated checking produces a shift in the memory source that is used to decide about the outcome of checking: from 'remembering' to 'knowing' (Tulving, 1985). Using the same interactive computer-animation, the earlier findings on vividness, detail and confidence were replicated. In addition, it was found that checking made participants endorse quotations from OCD patients (Reed, 1985) expressing a specific ambivalence about memory: 'It is as though the memory is there, but is isn't definite enough', 'I remember doing it in a way, but it's all fuzzy....' And 'I can remember that I've done it. But the memory isn't clear somehow'. This finding adds to the validity of the experimental model. Furthermore, after checking subjects' beliefs about the outcome of checking became based on (general) knowing instead of (specific) remembering. It is suggested that OCD checkers feel a general and relatively strong need to be certain about the veracity of recollections and that they have high standards for memory performance. This may explain earlier findings that OCD checkers have a general tendency to distrust their episodic memory. A need for certainty and a critical attitude towards memory performance may not be problematic or abnormal. It is suggested that clinical problems arise when the patient tries to fight memory distrust by repeated checking. The latter does not reduce distrust but rather increases distrust and the patient may get trapped in a spiral of mutually reinforcing checking behavior and memory distrust.  相似文献   
913.
The aims of this study of 24 normotensive subjects were: to compare a free-operant with a discrete-trials training format; to determine the most effective training procedure by comparing instrumental conditioning with instructional set and a control; to see if both increases and decreases in blood pressure could be brought under discriminative control, and to examine the maintenance of acquired self-control of blood pressure. A 2 × 3 design was employed in which two trial formats (free operant and discrete trials) were factorially compared with three training conditions (instrumental conditioning, instructional set, and control). Instrumental conditioning was found superior to both the instructional set and control conditions in producing increases and decreases in mean diastolic blood pressure. The free-operant format led to a greater degree of learned BP control in that subjects were able to increase and decrease their blood pressure by 10% to 15% of basal value and to maintain the blood-pressure operant after contingent auditory feedback/reinforcement was removed. Training was discontinued when subjects in the other five groups failed to reach criterion after 10 consecutive acquisition sessions.  相似文献   
914.
Home-observation data on 5- to 7-yr-old boys collected over 2 yr were examined for systematic variations in rates of desirable and undesirable behaviors associated with several temporal and climatic variables. Significant effects associated with time of day, day of the week, precipitation, and temperature were found. No significant effects on the naturalistic observation data were found for environmental factors associated with lunar phase. It was noted that the correlational nature of the findings did not obviate the necessity for control of the influence of temporal and climatic variables. Several methodological strategies for such control were discussed.  相似文献   
915.
In each of three components of a multiple schedule, monkeys were required to emit a different sequence of four responses in a predetermined order on four levers. Sequence completions produced food on a fixed-ratio schedule. Errors produced a brief timeout. One component of the multiple schedule was a repeated-acquisition task where the four-response sequence changed each session (learning). The second component of the multiple schedule was also a repeated-acquisition task, but acquisition was supported through the use of a stimulus-fading procedure (faded learning). In a third component of the multiple schedule, the sequence of responses remained the same from session to session (performance). At higher doses, d-amphetamine, cocaine, and phencyclidine decreased the overall rate of responding and increased the percent errors in all three components. At lower doses, however, the three drugs produced selective effects on errors. Errors were increased in the learning component at lower doses than those required to disrupt the behavior in the faded-learning component. The performance component tended to be the least sensitive to disruptive drug effects. The data are consistent with the view that stimulus fading can modulate the effects of drugs on acquisition.  相似文献   
916.
The present experiments were designed to test whether initial excitatory conditioning to a stimulus was obtained, using a within-subject design of the truly random control (TRC) procedure, and to examine the effects of the density of the conditioned stimulus on it. In Experiment 1, the effect of the three levels of CS density (50%, 25%, 20%) was assessed at six different stages of training, using the conditioned suppression of licking in rats. Although all of the groups given the TRC procedure showed evidence of initial excitatory conditioning, it was more marked in the group with the highest CS density than in the other groups. Experiment 2 confirmed the results of Experiment 1, using a between-subject design. The findings are in line with predictions from the Rescorla-Wagner model, and are discussed with reference to other contemporary theories of associative learning.  相似文献   
917.
The present study evaluated the efficacy of using contingent-interrupted music in treating the disruptive bus-riding behavior of an 8-year-old profoundly retarded female. Music was played during each bus ride as long as the subject was sitting appropriately, and interrupted contingent upon each response defined as disruptive bus riding, during an ABCDCDCDA design. A significant reduction in disruptive bus riding occurred with each introduction of contingent-interrupted music. The treatment procedure described in this report was easy to administer, produced rapid treatment gains, and showed virtually no regression during an 8-week follow-up period.  相似文献   
918.
In this study we refer to Craik and Bialystok's model distinguishing the “knowledge” (cultural learning experience that forms the basis for knowledge of the world) and the “executive control” (set of operations that control and regulate cognitive performance) as two main factors susceptible accounting for the age-related negative effects on the cognitive functioning, and for a possible age-related protective effect. Thus, the aim of the present study was to examine the possible protective effect of these two factors on the age-related decline in a cued-recall task. Four age groups of participants (20–39 years, 40–59 years, 60–74 years and 75–90 years) were administered with a word-stem cued-recall test to assess episodic memory, a “vocabulary” sub-test of the WAIS-R to assess knowledge and a reading span test to assess control. Results showed an age-related effect on the episodic memory, the control performance and the knowledge measure, indicating that performance decreases with age. A GLM analysis revealed a positive effect of the knowledge and the control factors on the cued-recall performance, and interaction between age and the knowledge factor resulting from a positive effect of the knowledge level only for the youngest group of participants (20–39 years). Furthermore, results revealed an interaction between age and the control factor, indicating a positive effect of the control level for the two oldest groups of participants (60–74 years and 75–90 years). These results suggest that, contrary to the knowledge, the control factor could be an effective protection against the age-related negative effects on the episodic memory.  相似文献   
919.
This study investigated whether external locus of control, as measured with the Rotter Internal-External Locus of Control Scale, is a specific feature of agoraphobia or whether it characterizes neurosis in general. Forty agoraphobic patients, 81 nonagoraphobic neurotic controls, and 49 normal controls completed the Dutch version of the Rotter Internal-External Locus of Control Scale. Agoraphobic patients were found to have a more external orientation as compared to the normal controls, but as a group, they could not be identified as being different from neurotic controls.This study was supported in part by a grant from the Dutch Organization for Fundamental Research (ZWO/Psychon 560-268-001).  相似文献   
920.
Rats repeatedly acquired the performance of selecting only the four baited arms in an automated eight-arm radial maze, with the arms containing food pellets randomly assigned prior to each session. During each 14-trial (trial: obtain all four pellets) daily session, the number of errors (selecting nonbaited arms or repeating arm selections) showed a within-session decline, and choice accuracy for the first four arm selections showed a positive acceleration across trials for all rats. An index-of-curvature statistic, calculated for total errors, was used to quantify both the within- and between-session improvement of performance. Scopolamine (0.03 to 0.3 mg/kg, ip), but not methylscopolamine (0.3 mg/kg), reduced the accuracy of the first four selections of each trial and increased total within-session errors for all rats. Session times also were increased by scopolamine. An examination of within-session accuracy showed only slight signs of improvement at the higher dosages of scopolamine. The results indicate that behavior in transition states maintained by reinforcement contingencies in the radial maze is similar to that maintained by extended chained schedules, despite the fact that some of the stimuli controlling behavior in the maze are absent at the moment behavior is emitted.  相似文献   
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