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291.
Fifth-grade children and college students were asked to remember some words and to forget others in an item-cued-directed-forgetting task. Taxonomically related pairs of words and control pairs that were unrelated in meaning were used as stimuli. Children found it more difficult than did adults to ignore forget-cued words that followed associatively related words that were remember-cued. The results provide support for D. F. Bjorklund and K. K. Harnishfeger's (1990) inefficient inhibition hypothesis (i.e., that the efficiency of inhibitory mechanisms improves as children develop). The results also suggest that the inhibition is occurring primarily in the early stages of processing.  相似文献   
292.
The dedifferentiation hypothesis is examined with respect to age-group differences, ability-group differences, attrition-group differences, and time. Cognitive and sensory data were analyzed from individuals (n = 1,823) who completed a clinical assessment on at least 1 of 3 occasions of measurement in the Australian Longitudinal Study of Ageing. Inconsistent dedifferentiation effects were associated with low ability and early attrition from the study, but age-related dedifferentiation was not found. Longitudinal analyses confirmed the cross-sectional analyses. Even though instances of dedifferentiation were identified between pairs of sensory and cognitive variables, consistent patterns of dedifferentiation were not found. These results do not support the view that shared biological factors become increasingly important for explaining within-individual change in cognitive and sensory function in later life.  相似文献   
293.
Although at the time of this article's publication, many anecdotes and cross-sectional studies had reported that law students experience significant distress during their 1st year, few researchers had controlled for prelaw school status (e.g., M. Garrison, B. Tomko, & I. Yip, 1996; L. Guinier, M. Fine, J. Balin, A. Bartow, & D. L. Stachel, 1994), and only a single group of researchers had explored a psychosocial factor that predicted these changes. The present authors tested 3 sets of potential predictors of adjustment: sources of stress, coping strategies, and relationship factors. The present data replicated declines in students' psychological health, physical health, and attitudes toward law over the 1st year of school. That result supports the generalizability and currency of previous studies. In contrast to other researchers, the present authors found few gender differences. Less relationship happiness, less emotional support, and use of less active coping tactics at the beginning of the year predicted poorer outcomes at the end of the year. Strain from academic pressures, lack of personal time, and social isolation were correlated with poorer outcomes.  相似文献   
294.
Solitude may be positive or negative, depending on situational and personal factors. From prior research, nine types of solitude were identified. Based on data from a questionnaire study of undergraduate participants, factor analysis suggests that these nine types can be reduced to three dimensions, two positive and one negative. These are, respectively, Inner-Directed Solitude (characterized by self-discovery and inner peace), Outer-Directed Solitude (characterized by intimacy and spirituality), and Loneliness. Personality and value correlates, as well as situational correlates, of the various types of solitude also were explored.  相似文献   
295.
296.
To address the lack of a simple and standardized instrument to assess overall illness severity of Tourette's disorder (TD), the authors developed and tested a 15-item scale to measure a broad range of common symptoms including tics, inattention, hyperactivity, obsessions, compulsions, aggression, and emotional symptoms. Independent investigators used the 15-item Tourette's Disorder Scale (TODS) to assess 60 TD patients who were taking part in a double-blind placebo-controlled multicenter 8-week treatment study. Interrater reliability, internal consistency, convergent and discriminant validity, and sensitivity to change were examined. The TODS was associated with good interrater reliability, excellent internal consistency, and favorable levels of validity and sensitivity to change. Individual TODS items showed good convergent and discriminant validity against other measures. The TODS is a simple, efficient way for clinicians and parents to rate the severity of multiple symptoms commonly found in patients with Tourette's disorder.  相似文献   
297.
In modern digital applications, users often interact with virtual representations of themselves or others, called avatars. We examined how these avatars and their perspectives influence stimulus–response compatibility in a Simon task. Participants responded to light/dark blue stimuli with left/right key presses in the presence of a task-irrelevant avatar. Changes in stimulus–response compatibility were used to quantify changes in the mental representation of the task and perspective taking toward this avatar. Experiments 1 and 2 showed that perspective taking for an avatar occurred in orthogonal stimulus–response mappings, causing a compatibility effect from the avatar’s point of view. In the following two experiments we introduced a larger variety of angular disparities between the participant and avatar. In Experiment 3, the Simon effect with lateralized stimulus positions remained largely unaffected by the avatar, pointing toward an absence of perspective taking. In Experiment 4, after avatar hand movements were added in order to strengthen the participants’ sense of agency over the avatar, a spatial compatibility effect from the avatar’s perspective was observed again, and hints of the selective use of perspective taking on a trial-by-trial basis were found. Overall, the results indicate that users can incorporate the perspective of an avatar into their mental representation of a situation, even when this perspective is unnecessary to complete a task, but that certain contextual requirements have to be met.  相似文献   
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299.
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   
300.
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