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931.
The MMPI-2 is often used for screening job applicants when public safety or security are at risk. Inherent in such applications is concern for profile validity and test defensiveness. In this study, we examine the impact of revised instructions on profile validity for a group of job applicants who initially produced invalid profiles. Participants were 271 male applicants for airline pilot positions. Of these, 72 produced invalid defensive MMPI-2 profiles during preemployment screening. The MMPI-2 was readministered to these applicants with instructions informing them of validity scales and instructing them to respond in a more open, honest manner. Comparisons were made between valid and invalid profiles for initial administrations and between valid and invalid profiles at readministration. Some clinical scales were more elevated for valid, nondefensive profiles. Most content scales showed more elevation for valid profiles, and 12% of the applicants who were retested produced significant elevations (T>or=65) on the content scales. Profiles were similar to those produced by employed pilots of a previous study. 相似文献
932.
Comparing Locomotion With Lever-press Travel In An Operant Simulation Of Foraging 总被引:2,自引:2,他引:0
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An operant model of foraging was studied. Rats searched for food by pressing on the left lever, the patch, which provided one, two, or eight reinforcers before extinction (i.e., zero reinforcers). Obtaining each reinforcer lowered the probability of receiving another reinforcer, simulating patch depletion. Rats traveled to another patch by pressing the right lever, which restored reinforcer availability to the left lever. Travel requirement changed by varying the probability of reset for presses on the right lever; in one condition, additional locomotion was required. That is, rats ran 260 cm from the left to the right lever, made one response on the right lever, and ran back to a fresh patch on the left lever. Another condition added three hurdles to the 260-cm path. The lever-pressing and simple locomotion conditions generated equivalent travel times. Adding the hurdles produced longer times in patches than did the lever-pressing and simple locomotion requirements. The results contradict some models of optimal foraging but are in keeping with McNair's (1982) optimal giving-up time model and add to the growing body of evidence that different environments may produce different foraging strategies. 相似文献
933.
934.
Studies in Philosophy and Education - 相似文献
935.
In studies using Averbach and Coriell’s (1961) partial-report bar-probe paradigm with linear arrays, most errors involve the naming of an item that was in the display but in a position other than the cued one. Up to now, there is no general agreement on the origin of these location errors. Point of departure in this paper is that part of the location errors arises from inappropriate application of the cue. It is tested whether this originates from problems to perceive the position of the cue (“cue-displacement hypothesis”) or from confusion about the order of the items in the array (“item-order hypothesis”). The results of two bar-probe experiments are reported. A novel, crucial, finding in both experiments is that, among the location errors, there was a preponderance of response letters that came from the central side of the cued item. In the second experiment, this was observed not only in the usual postcue conditions but also when the cue preceded the array. These results positively corroborate the cue-displacement hypothesis and do not support the item-order hypothesis: The cue tends to be perceived more toward the center of the visual field than it actually is exposed—that is, there is a central drift of the cue. 相似文献
936.
Craig R. Colder John E. Lochman Karen C. Wells 《Journal of abnormal child psychology》1997,25(3):251-263
Parenting practices have been previously linked to childhood symptomatology. However, little consideration has been given to the potential effect of individual differences within the child on this relation. The current study assessed the moderating effects of children's activity level and fear on relations between parenting practices and childhood aggression and depressive symptoms using a sample of 64 fourth-, and fifth-grade boys. The findings showed that poorly monitored active boys and fearful boys who were exposed to harsh discipline exhibited high levels of aggression. Boys characterized by high fear who were exposed to harsh discipline or whose parents were extremely overinvolved showed elevated levels of depressive symptoms. These findings suggest that integrating children's individual differences with parenting models enhances our understanding of the etiology of childhood symptomatology. The intervention implications of such an integration are discussed. 相似文献
937.
938.
The study of unimanual performance as a measure of laterality has ranged from simple concepts such as tests of handedness to highly complex conceptualizations interrelating anthropologic, cultural, genetic, and neurological aspects, including difference between unimanual performance in brain injured versus normal samples. This paper traces measures of unimanual performance through behavioral correlates of natural and unnatural sinistrality as related to cerebral organization, and concludes that unimanual performance represents a robust phenomenon with implications for understanding of neuropsychological correlates of behavior. 相似文献
939.
Ruben C. Gur J.Daniel Ragland Lyn Harper Mozley P.David Mozley Robin Smith Abass Alavi Warren Bilker Raquel E. Gur 《Brain and cognition》1997,33(3):388-414
Functional neuroimaging has been used to investigate neural substrates of mnemonic processes, and cerebral blood flow (CBF) measures have been sensitive to activation with memory tasks. Studies of memory with two-dimensional133Xenon clearance techniques found that word and face recognition tasks produced contralateral CBF changes in mid-temporal cortical regions. This study replicated the activation paradigm, expanding to the three-dimensional resolution of positron emission tomography (PET). Word and face recognition, and a control baseline task were administered to 19 healthy right-handed volunteers (11 men, 8 women) during successive 10 min PET15O-water measures of CBF. Quantitative CBF rates were calculated with the arterial input function and the equilibrium model. Redistributions of blood flow were compared across tasks using both absolute and relative (region/whole brain) CBF.Replicating the133Xenon clearance findings, CBF was “appropriately” lateralized during task performance (left–right for words > left–right for faces) in the mid-temporal region. Contrary to predictions, the recognition tasks did not activate expected mesolimbic or prefrontal areas. The task-induced CBF changes also correlated with performance. Bilateral CBF in mid-temporal and parahippocampal gyrus regions of interest correlated with the ability to correctly identify word targets (sensitivity). Left-lateralized CBF in the amygdala and hippocampus correlated with better word sensitivity as well as specificity (ability to correctly reject foils). Complementally, right-lateralized CBF in the parahippocampal gyrus correlated with better face specificity performance. In addition, left-lateralized CBF in the amygdala and right-lateralized CBF in the parahippocampal gyrus and hippocampus correlated with “mental effort” indices (task performance relative to basal ability) for word and face memory tasks, respectively. Thus, whereas this recognition task showed the expected lateralized increase in the mid-temporal region and not in frontal and limbic areas, lateralized activation in some of these areas was associated with better performance. Exploratory analyses on other regions showed lateralized changes in one additional temporal region, the occipital-temporal, and several limbic regions. 相似文献
940.
The etiology of the observed relationship between general cognitive ability and reading performance was investigated by analyzing data from samples of twin pairs tested in the Colorado Learning Disabilities Research Center. Bivariate phenotypic and genetic structural equation models were fitted to data from 486 twin pairs selected for reading deficits (276 identical and 210 same-sex fraternal) and 314 control pairs (195 identical and 119 same-sex fraternal). Subtests of the Peabody Individual Achievement test (Reading Recognition, Reading Comprehension, and Spelling) were used as measures of reading performance, and verbal and performance IQ scores from the Wechsler Intelligence Scale for Children-Revised (WISC-R) or Wechsler Adult Intelligence Scale-Revised (WAIS-R) were used as indices of general cognitive ability. The results of these confirmatory factor analyses indicate that shared environmental influences do not contribute significantly to covariation between general cognitive ability and reading performance. In contrast, genetic influences contribute substantially to the relationship between the two latent factors. Moreover, the genetic and phenotypic variances of reading performance in the proband group are larger than those in controls, whereas both the genetic and phenotypic correlations between reading performance and general cognitive ability are lower in probands. These results are consistent with recent reports that reading disability may be caused by one or more genes with major effects. 相似文献