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131.
Infants under 7 months of age fail to reach behind an occluding screen to retrieve a desired toy even though they possess sufficient motor skills to do so. However, even by 3.5 months of age they show surprise if the solidity of the hidden toy is violated, suggesting that they know that the hidden toy still exists. We describe a connectionist model that learns to predict the position of objects and to initiate a response towards these objects. The model embodies the dual-route principle of object information processing characteristic of the cortex. One route develops a spatially invariant surface feature representation of the object whereas the other route develops a feature blind spatial–temporal representation of the object. The model provides an account of the developmental lag between infants’ knowledge of hidden objects and their ability to demonstrate that knowledge in an active retrieval task, in terms of the need to integrate information across multiple object representations using (associative) connectionist learning algorithms. Finally, the model predicts the presence of an early dissociation between infants’ ability to use surface features (e.g. colour) and spatial–temporal features (e.g. position) when reasoning about hidden objects. Evidence supporting this prediction has now been reported. 相似文献
132.
Julie Aitken Harris Robert Saltstone Maryann Fraboni 《Journal of business and psychology》1999,13(3):447-455
A modified version of Caplan's Job Stress Questionnaire (JSQ) was administered to 169 male and 56 female entrepreneurs. Entrepreneurs were found to have higher levels of stress associated with workload than with role ambiguity and underutilization of skills. Compared to scores reported previously for various occupational categories, the entrepreneurs scored significantly higher than did white collar, blue collar, and professional groups on the workload scale and significantly lower on scales measuring role ambiguity and under-utilization of skills. These results may be due to the nature of entrepreneurial activity, which is often characterized by heavy workloads, long hours, and a self-established role in the organization. Additionally, the factorial composition of the JSQ and its internal consistency were examined. Evidence of convergent and discriminant validity at the item and subscale level confirmed the a priori dimensions of the JSQ, although the internal consistency of the scales were low to moderate. The need for various improvements in the measurement of occupational stress is briefly discussed. 相似文献
133.
This study examined the relations between maternal criticism and externalizing and internalizing symptoms in adolescents who varied in their risk for psychopathology. Both maternal-effects and child-effects models were examined. The sample consisted of 194 adolescents (mean age = 11.8~years) and their mothers; 146 mothers had a history of depressive disorders and 48 did not. When adolescents were in 6th and 8th grade, maternal criticism was measured with the five-minute speech sample and adolescents symptoms were assessed with the Child Behavior Checklist. Maternal criticism was significantly associated with both adolescents externalizing and internalizing symptoms, beyond the contribution of the chronicity/severity of mothers depression history. Maternal criticism did not mediate the relation between maternal depression and adolescent symptoms. In contrast, adolescent externalizing behaviors mediated the relation between chronicity/severity of maternal depression history and maternal criticism in 6th grade. Prospective analyses showed that adolescents externalizing symptoms in 6th grade significantly predicted maternal criticism in 8th grade, controlling for maternal depression history and prior maternal criticism. Results are discussed in terms of the importance of examining child-effects models in studies of maternal criticism. 相似文献
134.
Alice A Keyl-Austin Andrew L Samaha Sarah E Bloom Megan A Boyle 《Journal of applied behavior analysis》2012,45(3):637-641
We examined correspondence between preference assessment outcome and within‐session patterns of responding in one subject with autism. Responding maintained by a single highly preferred item resulted in a greater total number of responses, a slower decline in within‐session response rates, and a greater proportion of short interresponse times compared to responding maintained by varied moderately preferred (MP) stimuli. Presenting varied MP stimuli within the same session produced greater levels and more sustained responding than presenting those same stimuli individually. 相似文献
135.
Michael D. Young Alice F. Healy Cleotilde Gonzalez Varun Dutt Lyle E. Bourne Jr. 《Applied cognitive psychology》2011,25(3):395-407
Three experiments simulating military RADAR detection addressed a training difficulty hypothesis (training with difficulty promotes superior later testing performance) and a procedural reinstatement hypothesis (test performance improves when training conditions match test conditions). Training and testing were separated by 1 week. Participants detected targets (either alphanumeric characters or vehicle pictures) occurring among distractors. Two secondary tasks were used to increase difficulty (a concurrent, irrelevant tone‐counting task and a sequential, relevant action‐firing response). In Experiment 1 , involving alphanumeric targets with rapid displays, tone counting during training degraded test performance. In Experiment 2, involving vehicle targets with both sources of difficulty and slower presentation times, training under relevant difficulty aided test accuracy. In Experiment 3, involving vehicle targets and action firing with slow presentation times, test accuracy tended to be worst when neither training nor testing involved difficult conditions. These results show boundary conditions for the training difficulty and procedural reinstatement hypotheses. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
136.
137.
Diane J. Harris 《Journal of multicultural counseling and development》1992,20(4):158-167
The Afrocentric model is an approach to identify problems and develop strategies to enhance the sense of belonging, identity, and control in African-American females. 相似文献
138.
Four experiments examined the memory processes used to maintain location in a counting sequence. In Experiment 1, subjects who rapidly counted forward omitted many repeated-digit numbers (e.g., 77), as found previously with backward counting. Subjects in Experiment 2 counted backward with normal auditory feedback or with headphones through which white noise was channeled. In both cases, repeated-digit errors predominated, suggesting that the contents of short-term memory, rather than auditory sensory memory, are checked during counting. In Experiment 3, subjects silently wrote counting responses, and the omission errors resembled those in vocal counting. Repetition errors were also found and attributed to phonological recoding failures. Articulatory suppression in Experiment 4 greatly increased the number of repetition errors in the written counting task. A model of the counting process was proposed according to which subjects keep track of their location in the counting sequence by monitoring phonologically coded short-term memory representations of the numbers. 相似文献
139.
Gould MS Greenberg T Munfakh JL Kleinman M Lubell K 《Suicide & life-threatening behavior》2006,36(6):601-613
The purpose of this study was to examine the attitudes toward the use of telephone crisis services (hotlines) among 519 adolescents in 9th through 12th grade mandatory health courses in six high schools in New York State. Few adolescents (2.1%) used hotlines and negative attitudes were stronger toward hotlines than they were toward other formal sources of help. The most common reasons for hotline nonuse related to feelings of self-reliance and shame. Objections to hotlines were strongest among students most in need of help by virtue of impaired functioning or feelings of hopelessness. The results underscore needed outreach efforts to youth. 相似文献
140.
L J Harris 《Brain and language》1991,40(1):1-50
According to several recent historical accounts, Broca (1865a) stated that left-handers are the mirror-reverse of right-handers for cerebral control of speech, with the right hemisphere being dominant in left-handers, and the left hemisphere dominant in right-handers. The same accounts then note Broca's error in light of current evidence that the majority of left-handers are left-dominant for speech just as are nearly all right-handers. Eling (1984) has called such statements misrepresentations of Broca's position and has argued that Broca's analysis actually was more compatible with the current view that there is a disjunction, meaning an absence of an intimate anatomical relationship, between cerebral control for handedness and speech. The current paper looks again at Broca's work, describes the context in which his views were first articulated, and traces the development of the mirror-reversal principle. The conclusion is reached that, judged by a narrow reading of the 1865 paper, Broca's views could indeed be construed as an anticipation of the modern disjunction principle. However, judged by a broader reading, by consideration of his other writing, and in the context of the philosophical and scientific tradition that shaped his work, it is suggested that it was the mirror-reversal principle to which Broca was actually disposed. 相似文献