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861.
Experiments were conducted in which observers learned to classify simple perceptual stimuli into low-variability and high-variability categories. Similarities between objects were measured in independent psychological-scaling tasks. The results showed that observers classified transfer stimuli into the high-variability categories with greater probability than was predicted by a baseline version of an exemplar-similarity model. Qualitative evidence for the role of category variability on perceptual classification, which could not be explained in terms of the baseline exemplar-similarity model, was obtained as well. Possible accounts of the effects of category variability are considered in the General Discussion section.  相似文献   
862.
Exposure to electrical current via industrial or residential accidents or lightning strikes is a serious and growing concern in today's medical community. The sequelae that result are referred to as electrical injury (EI) or lightning injury (LI). The relevant principles in electricity are reviewed with particular attention given to their damaging capabilities on the body. Specific neuropsychological, psychiatric, and neurological signs and symptoms as well as objective measures of psychological and neuropsychological functioning and brain imaging in victims of EI and LI, are reviewed from past research. Important issues relevant to researchers in the field are discussed. Finally, the role that neuropsychology might play in this area is outlined.  相似文献   
863.
In the West, we have adoped the word calligraphy to describe Chinese and Japanese writing out of the recognition that there is an aesthetic component inherent in the written characters. The author shows how Chinese and Japanese calligraphy is much more than writing; it must be approached as one would any piece of art. A brief history of Chinese and Japanese calligraphy is explored, including the elements and methods of brushwork and overall creation of the expressions themselves. The article concludes by looking at how calligraphy is a mode of self-discovery and self-development that opens us to a substantial dialogue between cultures and the paths of inner conversation.  相似文献   
864.
865.
The purpose of this study was to determine whether an association exists between neuropsychological deficits and conduct disorder (CD) with and without concurrent attention-deficit–hyperactivity disorder (ADHD). In addition, we explored the differential neuropsychological performance of aggressive and nonaggressive CD adolescents and the combined effect of this behavioral status and ADHD on performance. Fifty-nine adolescents (mean age of 15.4 years) who met the criteria for CD were compared with 29 controls comparable in age, gender, and socioeconomic status. A neuropsychological battery of current tests measuring executive functions and a battery of language tests were used in the study. Multivariate analyses showed that, compared with controls, CD adolescents had significantly lower verbal skills but did not differ on executive function measures. However, the lower verbal performance of CD adolescents is not explained by the existence of a CD subgroup with concomitant ADHD or aggressiveness. The study confirms with a sample of CD adolescents the association between verbal deficits and antisocial behavior when socioeconomic status is controlled. Our results also demonstrate that CD per se can be a sufficient condition for such deficits.  相似文献   
866.
Pino  Nathan W.  Meier  Robert F. 《Sex roles》1999,40(11-12):979-990
This paper compares male and female rapereporting behavior. Participants from National Crime andVictimization Survey data (90% female, 10% male) aremuch like victims of other violent crimes (25%non-white, higher than average unemployment, young, andunmarried). The data indicate that the situationalcharacteristics of rape, and factors that influence arape reporting decision, differ by sex. Whereas men fail to report rape when it jeopardizes theirmasculine self-identity, women fail to report rape whenthe rape does not fit the classic stereotypical rapesituation. Women reported victimization more frequently than did men. It is asserted that furthercomparative research on rape reporting behaviorutilizing qualitative methods is needed in order tofully understand rape victimization for bothsexes.  相似文献   
867.
Zusammenfassung. Das hier vorgestellte Modell lernt graduell, Planungsaufgaben aus der Klasse der Maschinenbelegungsprobleme (job-shop-scheduling problems) zu lösen. Mit Hilfe des Chunking-Mechanismus von Soar wird episodisches Wissen über die Belegungsreihenfolge von Aufträgen auf Maschinen memoriert. Bei der Entwicklung des Modells wurden zahlreiche qualitative (z. B. Transfereffekte) und quantitative Befunde (z. B. Bearbeitungszeiten) aus einer früheren empirischen Untersuchung berücksichtigt. In einer Validierungsstudie wurden dieselben Aufgaben von 14 Probanden und dem Modell bearbeitet. Die Passung von Simulationsdaten und empirischen Ergebnissen fiel insgesamt gut aus. Allerdings löst das Modell die Aufgaben schneller und zeigt auch einen etwas besseren Lernverlauf als die Probanden. Das Modell liefert eine Erklärung für das Rauschen, das typischerweise bei Bearbeitungszeiten zu beobachten ist: es handelt sich um erworbenes Wissen, das mehr oder weniger gut und auch unterschiedlich häufig auf neue Situationen übertragen wird. Der Lernverlauf der Probanden entspricht nur für aggregierte Daten einer Potenzfunktion (power law). Der vorgestellte Mechanismus zeigt, wie ein symbolisches Modell der Informationsverarbeitung graduelle Verhaltensänderungen generiert und wie der offensichtliche Erwerb allgemeiner Prozeduren ohne explizites Lernen von deklarativen Regeln erfolgen kann. Es wird nahegelegt, daß es sich hier um die Modellierung einer Form impliziten Lernens handelt. Summary. The model presented here gradually learns how to perform a job-shop scheduling task. It uses Soar's chunking mechanism to acquire episodic memories about the order to schedule jobs. The model was based on many qualitative (e.g., transfer effects) and quantitative (e.g., solution time) regularities found in previously collected data. The model was tested with new data where scheduling tasks were given to the model and to 14 subjects. The model generally fit these data with the restrictions that the model performs the task (in simulated time) faster than the subjects, and its performance improves somewhat more quickly than the subjects' performance. The model provides an explanation of the noise typically found in problem solving times - it is the result of learning actual pieces of knowledge that transfer more or less to new situations but rarely by an average amount. Only when the data are averaged (i.e., over subjects) does the smooth power law appear. This mechanism demonstrates how symbolic models can exhibit a gradual change in behavior and how the apparent acquisition of general procedures can be performed without resorting to explicit declarative rule generation. We suggest that this may represent a type of implicit learning.  相似文献   
868.
869.
870.
Linguistics must again concentrate on the evolutionary nature of language, so that language models are more realistic with respect to human natural languages and have a greater explanatory force. Multi-agent systems are proposed as a possible route to develop such evolutionary models and an example is given of a concrete experiment in the origins and evolution of word-meaning based on a multi-agent approach.  相似文献   
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