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931.
The construct validity of psychopathy was examined in a sample of 114 male and female young offenders (Mage = 15.16) at a southeastern detention center. The interpersonal circumplex served as a framework of general personality from which to examine the construct of adolescent psychopathy. A supplementary analysis of the psychopathy measures and the Big 5 factors of personality was also conducted using a matrix approach. Measures included: (a) Antisocial Process Screening Device (P. J. Frick & R. D. Hare, 2001); (b) Child Psychopathy Scale (D. R. Lynam, 1996); (c) Psychopathy Checklist—Youth Version (A. E. Forth, D. S. Kosson, & R. D. Hare, 2003); and (d) Interpersonal Adjective Scales Revised—Big 5 Version (P. Trapnell & J. S. Wiggins, 1991; J. S. Wiggins, 1995). Results showed substantial convergence among the three psychopathy measures. In addition, meaningful associations between psychopathy and constructs within the interpersonal circumplex and broader domains of the Big 5 were obtained. Two psychopathy scales correlated to a higher degree than expected with neuroticism. These findings provide evidence linking personality theory to the concept of child and adolescent psychopathy, thereby adding to its construct validity. However, they do so with the caveat that youth may also be displaying some characteristics of neuroticism, suggesting that worry and anxiety may accompany psychopathic features in earlier developmental stages. The implications of the current study are discussed.  相似文献   
932.
The authors examined the prioritization of abruptly appearing objects in real-world scenes by measuring the eyes' propensity to be directed to the new object. New objects were fixated more often than chance whether they appeared during fixations (transient onsets) or saccades (nontransient onsets). However, onsets that appeared during fixations were fixated sooner and more often than those coincident with saccades. Prioritization of onsets during saccades, but not fixations, were affected by manipulations of memory: Reducing scene viewing time prior to the onset eliminated prioritization, whereas prior study of the scenes increased prioritization. Transient objects draw attention quickly and do not depend on memory, but without a transient signal, new objects are prioritized over several saccades as memory is used to explicitly identify the change. These effects were not modulated by observers' expectations concerning the appearance of new objects, suggesting the prioritization of a transient is automatic and that memory-guided prioritization is implicit.  相似文献   
933.
We investigated the effect of contextual cuing (M. M. Chun & Y. Jiang, 1998) within the preview paradigm (D. G. Watson & G. W. Humphreys, 1997). Contextual cuing was shown with a 10-item letter search but not with more crowded 20-item displays. However, contextual learning did occur in a preview procedure in which 10 preview items were followed by 10 new items. Repeating the new items alone did not generate contextual learning, but repeating the preview items alone did, as long as they had a consistent spatial relation with the target. This was not merely due to the onset of the preview items being associated with the target location. No learning effect took place with a preview of homogeneous items that competed less for selection with new stimuli. The results provide evidence for old items being processed in preview search and providing a context for subsequent search of new items.  相似文献   
934.
The aim of the experiment was to investigate how bi-phasic hitting movements are organized to comply with both impact and temporal precision constraints. 'Bi-phasic' refers to a sequential movement with a preparatory movement away from the interception location followed by a strike phase. The interception location was fixed, as the motion of the hitting device was constrained to follow a straight path orthogonal to that of the approaching balls. We manipulated the required temporal precision by projecting balls with different constant approach speeds (1, 1.5, and 2m/s). Different impact constraints were imposed by instructing participants first to simply hit the ball and subsequently to hit the ball to a designated target area located either 55 or 105 cm away from the interception location. We determined several kinematic variables and used Principal Component Factor Analysis to classify these variables. The analysis revealed two independent factors: a 'velocity' factor (formed by impact velocity, peak velocity of the preparatory phase, peak velocity of the strike phase, and amplitude of the strike) and a 'timing' factor (formed by onset of the preparatory phase, moment of peak velocity of the preparatory phase, and onset of the strike phase). The 'velocity' factor scaled significantly with the required impact constraint and the 'timing' factor scaled significantly with ball speed.  相似文献   
935.
We explore the relationship between ethnomethodology (EM), ethnography and the needs of managers and designers in industry, considering both ethnomethodological and industrial criteria of adequacy and explicating their relationship through the concept of “audience.” We examine a range of studies in this light, with a view to their possible candidacy as hybrid studies and identify three types of application of EM studies of work: market research, design, and business improvement. Application in the first of these fields we dub “anthropological,” in that it consists in studying and reporting back on the ways of exotic people (customers). This is the application most commonly found in studies of computer supported co-operative work (CSCW). A second CSCW application, “technomethodology,” involves the introduction of EM concepts into the design process. A further application, dubbed “holding-up-a-mirror,” involves reporting back to members of a setting upon their own activities. We argue that technomethodology and holding-up-a-mirror both offer the possibility of creating hybrid disciplines. We consider the objection that improvement and design involve the introduction of value judgements that threaten the practice of EM indifference, arguing that action research can serve as a guarantee of unique adequacy (UA) by testing the researcher’s understanding as analysis in action in the setting. Furthermore, the standard of reporting required by the UA criterion contributes to the effectiveness of proposed solutions.  相似文献   
936.
Judgments of learning (JOLs) made during multiple study-test trials underestimate increases in recall performance across those trials, an effect that has been dubbed the underconfidence-with-practice (UWP) effect. In 3 experiments, the authors examined the contribution of retrieval fluency to the UWP effect for immediate and delayed JOLs. The UWP effect was demonstrated with reliable underconfidence on Trial 2 occurring for both kinds of JOL. However, in contrast to a retrieval-fluency hypothesis, fine-grained analyses indicated that the reliance of JOLs on retrieval fluency contributed minimally to the UWP effect. Our discussion focuses on the status of the retrieval-fluency hypothesis for the UWP effect.  相似文献   
937.
The associative learning effects called blocking and highlighting have previously been explained by covert learned attention, but evidence for learned attention has been indirect, via models of response choice. The present research reports results from eye tracking consistent with the attentional hypothesis: Gaze duration is diminished for blocked cues and augmented for highlighted cues. If degree of attentional learning varies across individuals but is relatively stable within individuals, then the magnitude of blocking and highlighting should covary across individuals. This predicted correlation is obtained for both choice and eye gaze. A connectionist model that implements attentional learning is shown to fit the data and account for individual differences by variation in its attentional parameters.  相似文献   
938.
A cued, visuospatial attention task and a working memory task were administered to 89 healthy adults genotyped for a T-to-C polymorphism in CHRNA4, a nicotinic receptor subunit gene. Increasing gene dose of the C allele of the CHRNA4 gene (i.e., no C alleles, one C allele, two C alleles) was associated with increased reaction time (RT) benefits of valid attentional cuing and reduced RT costs of invalid cues, but was not associated with working memory performance. In a second experiment, 103 healthy persons were genotyped for a G-to-A polymorphism of the dopamine beta-hydroxylase (DBH) gene. Increasing gene dose of the G allele of the DBH gene was associated with increased working memory accuracy at a high memory load. However, there was no consistent association between the DBH gene and visuospatial attention. Thus, a double dissociation was observed, with visuospatial attention associated with CHRNA4 but not the DBH gene and, conversely, working memory associated with the DBH gene but not CHRNA4. The results show that normal allelic variations in single neurotransmitter genes modulate individual differences in processing components of cognitive functions in healthy individuals.  相似文献   
939.
BACKGROUND: This study investigated the nature and functioning of the visual-spatial inhibition of return (IOR) phenomenon in children with "pure" Tourette's syndrome (TS), and those with comorbid forms of TS. METHOD: Children with TS-only and "TS + comorbid" (TS + ADHD +/- OCD) and matched controls performed the inhibition of return (IOR) task, which involved responding to left and right visual targets appearing on a computer screen that were preceded by congruent or incongruent exogenous visual cues. RESULTS: The TS-only group performed similarly on the IOR task to the controls. When the TS-only group was subdivided into children with mild and severe TS symptoms, a post hoc comparison between the controls and severe TS symptom children revealed that these TS children had a reduced magnitude of IOR for targets appearing in the right visual field. The comparison between the TS + comorbid and controls revealed an atypical IOR pattern for the TS + comorbid group. They displayed a loss of normal facilitatory and inhibitory effects for right visual field targets. CONCLUSIONS: The findings suggest abnormalities in attentional "disengage" and "move" mechanisms in TS when directing attention to the right visual field, which may reflect left posterior parietal, superior colliculus, and midbrain pathology.  相似文献   
940.
Research on skilled memory has focused on organizational processes to the exclusion of item-specific processes, although theories of skilled memory do acknowledge the importance of both kinds of processes. Using the isolation methodology, we presented lists of American football team names to participants who had either a high or a low level of knowledge about American football. An isolation effect (greater recall of the target in the isolate list than in a homogeneous control list) was observed only with high-knowledge participants. When standard lists were used, an isolation effect was observed with both groups. These findings empirically validate the importance of both organizational and item-specific processing as the basis of distinctive processing underlying skilled memory performance.  相似文献   
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