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991.
This study explored the relationship among love deprivation, Performance greater than Verbal discrepancy, and violent crime in a sample of juvenile probationers. Love deprivation and P greater than V discrepancy was significantly related to violent delinquency after adjusting for the effects of both race and social class, two variables often closely associated with violent delinquency. Also, love deprivation was strongly related to P greater than V discrepancy. We speculated that high performance IQ scores relative to verbal scores are a function of a lack of disruption in the short-term memory mechanisms of high P greater than V subjects, that this nondisruption is a function of hyporeactive autonomic nervous systems, and that this hyporeactivity could itself be a function of early love deprivation.  相似文献   
992.
The purpose of this study was to explore differences in body satisfaction among female adolescents 14 to 18 years of age. Principal components analysis of a body cathexis measure completed by 751 high school cheerleaders indicated that six factors defined the adolescents' attitudes toward their bodies: satisfaction with the midsection and overall appearance, peripheral body parts, hair and face, mouth, hands, and height. An Age X Body Satisfaction multivariate analysis of variance (MANOVA) was conducted; a Bonferroni adjusted alpha of .007 was established for subsequent ANOVAs. Satisfaction with the mouth increased significantly as age increased, and a similar but nonsignificant trend was found for peripheral body parts. The findings contradict previous research reporting no age differences in the body satisfaction of adolescents. Role demands and physical maturation of the cheerleaders may explain differences based on age.  相似文献   
993.
The Threat Index and the Death Anxiety Scale were administered to 228 subjects. Based on the high/low criterion scores, 105 subjects were assigned to the following four groups: (a) high death threat/high death anxiety, (b) high death threat/low death anxiety, (c) low death threat/high death anxiety, and (d) low death threat/low death anxiety. During the experimental phase of the study, subjects viewed a filmstrip on death rituals in various cultures. A recall test was then administered. Results indicated no significant group differences on recall performance. Initial no-show rates for the second part of the experiment were observed in the four groups reflecting a significant negative relationship between death anxiety and initial no-show rates. The possibility of defensive responding on the Death Anxiety Scale was suggested.  相似文献   
994.
The nature of the relationship between obsessive-compulsive personality and obsessive-compulsive disorder has been the subject of considerable debate. The present article dealt with clinical opinion and reviewed empirical data bearing on this issue. It was concluded that, although the two clinical entities bear a surface similarity in terms of shared behavioral features and defenses, obsessive-compulsive personality is neither a necessary nor sufficient factor in the development of obsessive-compulsive disorder, though the latter appears to be more frequently associated with premorbid obsessive-compulsive personality patterns than with other personality patterns. Suggestions for future research study are made.  相似文献   
995.
Stimulus class membership established via stimulus-reinforcer relations   总被引:4,自引:4,他引:0  
In an arbitrary matching-to-sample procedure, two mentally retarded subjects learned conditional discriminations with two sets of stimuli. Each set included a spoken name (N1 or N2), an object (O1 or O2), and a printed symbol (S1 or S2). One subject selected conditionally (a) O1 upon N1, and O2 upon N2, and (b) S1 upon O1, and S2 upon O2. The other subject selected conditionally (a) S1 upon N1, and S2 upon N2, and (b) O1 upon S1, and O2 upon S2. For both subjects, selections of O1 and S1 produced one type of food, F1; selections of O2 and S2 produced a different type of food, F2. Both subjects also learned identity-matching performances, selecting O1, O2, S1, S2, F1, and F2 conditionally upon those stimuli as samples; F1 followed selections of O1, S1, and F1; F2 followed selections of O2, S2, and F2. Matching performances consistent with stimulus class formation involving the names, objects, symbols, and foods were demonstrated on probe trials, even though these performances had not been taught explicitly. Next, new objects, X1 and X2, were presented on identity-matching trials, producing F1 and F2, respectively. Without further training, X1 was selected conditionally upon N1, S1, and O1, and X2 was selected upon N2, S2, and O2. When the contingencies were changed so that selections of X1 and X2 were now followed by F2 and F1, respectively, X2 was selected conditionally upon N1, S1, and O1, and X1 was selected upon N2, S2, and O2. Class membership of X1 and X2 had apparently changed. This study provides evidence that reinforcers may become members of stimulus classes, and that new stimuli may become class members through relations with reinforcers.  相似文献   
996.
Six pigeons were trained in a discrete-trials signal-detection procedure to discriminate between a fixed-duration stimulus (5 s or 20 s) and a set of variable durations ranging from 2.5 s to 57.5 s in steps of 5 s. For each fixed-duration stimulus, the ratio of reinforcer frequencies contingent upon reporting the fixed versus the variable stimulus was systematically manipulated. Detection performance was well controlled by both the stimulus value and the reinforcer ratio. Both the discriminability between the fixed duration and the set of variable durations, and the discriminability between the fixed duration and each of the variable durations, were independent of the reinforcer-frequency ratio when discriminability was measured as log d. The sensitivity of response bias to reinforcement-ratio changes was independent of the value of the fixed duration, but was not independent of the discriminability of the variable durations from the fixed durations. Under current models, discriminability measures in complex temporal discrimination may be independent of biasing manipulations, but bias measures are not independent of stimulus values.  相似文献   
997.
Pigeons' choices between alternatives that provided different percentages of reinforcement in mixed schedules were studied using the concurrent-chains procedure. In Experiment 1, the alternatives were terminal-link schedules that were equal in delay and magnitude of reinforcement, but that provided different percentages of reinforcement, with one schedule providing, reinforcement twice as reliably as the other. All pigeons preferred the more reliable schedule, and their level of preference was not systematically affected by variation in the absolute percentage values, or in the magnitude of reinforcement. In Experiment 2, preference for a schedule providing 100% reinforcement over one providing 33% reinforcement increased systematically with increases in the duration of the terminal links. In contrast, preference decreased systematically with increases in the duration of the initial links. Experiment 3 examined choice with equal percentages of reinforcement but unequal delays to reinforcement. Preference for the shorter delay to reinforcement was not systematically affected by variation in the absolute percentage of reinforcement. The overall pattern of results supported predictions based on an extension of the delay-reduction hypothesis to choice procedures involving mixed schedules of percentage reinforcement.  相似文献   
998.
Effects of delayed conditioned reinforcement in chain schedules.   总被引:3,自引:3,他引:0  
The contingency between responding and stimulus change on a chain variable-interval 33-s, variable-interval 33-s, variable-interval 33-s schedule was weakened by interposing 3-s delays between either the first and second or the second and third links. No stimulus change signaled the delay interval and responses could occur during it, so the obtained delays were often shorter than the scheduled delay. When the delay occurred after the initial link, initial-link response rates decreased by an average of 77% with no systematic change in response rates in the second or third links. Response rates in the second link decreased an average of 59% when the delay followed that link, again with little effect on response rates in the first or third links. Because the effect of delaying stimulus change was comparable to the effect of delaying primary reinforcement in a simple variable-interval schedule, and the effect of the unsignaled delay was specific to the link in which the delay occurred, the results provide strong evidence for the concept of conditioned reinforcement.  相似文献   
999.
1000.
We develop a simple model of switching between the initial links of a concurrent-chain procedure. Behavior is determined by four parameters μ1, μ2, q1, and q2. The first two are the basic rates of switching from Schedule 1 and Schedule 2, respectively. The second two are the probabilities of leaving Schedule 1 and Schedule 2 after the corresponding terminal link has been completed. We show that for fixed values of these four parameters, the relative allocation on the initial links may change as a result of changes in initial-link schedules. The effect can be quite large if the switching rates are low. An implication is that relative allocation is not necessarily a good measure of behavior.  相似文献   
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