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991.
It is reported that (1) a new coordinate estimation routine is superior to that originally proposed for ALSCAL; (2) an oversight in the interval measurement level case has been found and corrected; and (3) a new initial configuration routine is superior to the original. 相似文献
992.
Characterizing cognition in ADHD: beyond executive dysfunction 总被引:19,自引:0,他引:19
The hypothesis that Attention-Deficit/Hyperactivity Disorder (ADHD) reflects a primary inhibitory executive function deficit has spurred a substantial literature. However, empirical findings and methodological issues challenge the etiologic primacy of inhibitory and executive deficits in ADHD. Based on accumulating evidence of increased intra-individual variability in ADHD, we reconsider executive dysfunction in light of distinctions between 'hot' and 'cool' executive function measures. We propose an integrative model that incorporates new neuroanatomical findings and emphasizes the interactions between parallel processing pathways as potential loci for dysfunction. Such a reconceptualization provides a means to transcend the limits of current models of executive dysfunction in ADHD and suggests a plan for future research on cognition grounded in neurophysiological and developmental considerations. 相似文献
993.
Visual working memory depends on attentional filtering 总被引:2,自引:0,他引:2
Working memory holds information actively being used in cognitive performance. Two important aspects of working memory are how many items it can hold, and how efficiently it can be used. Recently, Vogel and colleagues used event-related brain potentials to show that these two things are related. People who could remember more objects from a spatial array also more efficiently excluded irrelevant objects. The results raise important questions about what aspect of working memory is most fundamental. 相似文献
994.
Story Recall and Narrative Coherence of High-Functioning Children with Autism Spectrum Disorders 总被引:5,自引:0,他引:5
Previous research has found few quantitative differences between children with high-functioning autism spectrum disorders (ASDs) and well-matched controls in the length, complexity, and structure of their narratives. Researchers have noted, however, that narratives of children with ASDs have an unusual and idiosyncratic nature. This study provides an analysis of narratives in 17 children with high-functioning ASDs and 17 typically developing children matched on age, gender, language abilities, and cognitive abilities. We examined story recall and narrative coherence. The study revealed no group differences in story length or syntactic complexity. Children with ASDs also did not differ from controls in their use of the gist of a story to aid recall, or in their sensitivity to the importance of story events. Children with ASDs did, however, produce narratives that were significantly less coherent than the narratives of controls. Children with ASDs appeared less likely to use the gist of the story to organize their narratives coherently. These findings are discussed with regard to their relationship to other cognitive and linguistic difficulties of children with ASDs. 相似文献
995.
At the time of this writing, a widely publicized, waived-consent trial is underway. Sponsored by Northfield Laboratories, Inc. (Evanston, IL) the trial is intended to evaluate the emergency use of PolyHeme, an oxygen-carrying resuscitative fluid that might prevent deaths from uncontrolled bleeding. The protocol allows patients in hemorrhagic shock to be randomized between PolyHeme and saline in the field and, still without consent, randomized between PolyHeme and blood after arrival at an emergency department. The Federal regulations that govern the waiver of consent restrict its applicability to circumstances where proven, satisfactory treatments are unavailable. Blood-the standard treatment for hemorrhagic shock-is not available in ambulances but is available in hospitals. The authors argue that the in-hospital stage of the study fails to meet ethical and regulatory standards. 相似文献
996.
Scores on the Clock Drawing Test have long been considered a useful screening tool for neuropsychological dysfunction, and a number of scoring methods have been developed to evaluate various aspects of performance. This study compared quantitative and qualitative scoring by briefly trained students on 145 clock drawings produced by patients in a geriatric psychiatry outpatient clinic to estimate the interrater reliability of the methods, user's acceptance of the methods, and whether the methods provide differential diagnosis. Both systems showed acceptable interrater reliability. Using the quantitative method, raters scored drawings by patients with organic mental disease as more impaired than those patients diagnosed as depressed or schizophrenic. Results suggest that the Clock Drawing Test is a reliable screening tool for cognitive impairment in a geropsychiatric population, but the scoring methods examined do not yet appear psychometrically sound enough to provide a differential diagnosis. 相似文献
997.
Children's questions may reveal a great deal about the characteristics of objects they consider to be conceptually important. Thirty-two preschool children were given opportunities to ask questions about unfamiliar artifacts and animals. The children asked ambiguous questions such as "What is it?" about artifacts and animals alike. However, they were more likely to ask about the functions of artifacts, but about category membership, food choices, and typical locations of animals. They never asked questions about either artifacts or animals that would be considered inappropriate by adults. The results indicate that children hold different expectations about the types of information important for categorizing living and artifact kinds. Young children conceive of artifacts in terms of functions, but conceive of animals in terms of biologically appropriate characteristics. Such results speak to debates about the role of function in children's biological reasoning and to accounts of children's artifact concepts. 相似文献
998.
People often choose intuitive rather than equally valid nonintuitive alternatives. The authors suggest that these intuitive biases arise because intuitions often spring to mind with subjective ease, and the subjective ease leads people to hold their intuitions with high confidence. An investigation of predictions against point spreads found that people predicted intuitive options (favorites) more often than equally valid (or even more valid) nonintuitive alternatives (underdogs). Critically, though, this effect was largely determined by people's confidence in their intuitions (intuitive confidence). Across naturalistic, expert, and laboratory samples (Studies 1-3), against personally determined point spreads (Studies 4-11), and even when intuitive confidence was manipulated by altering irrelevant aspects of the decision context (e.g., font; Studies 12 and 13), the authors found that decreasing intuitive confidence reduced or eliminated intuitive biases. These findings indicate that intuitive biases are not inevitable but rather predictably determined by contextual variables that affect intuitive confidence. 相似文献
999.
1000.
This research addressed three issues. First, we examined whether retrospective confidence judgments (RCJs) and judgments of learning (JOLs) assess memory differently. Second, we examined the relative accuracy of JOLs and RCJs at predicting future recall performance. Third, we examined whether making JOLs improves subsequent recall better than making RCJs or making no metacognitive judgment. Results suggest that RCJs and JOLs are both based on retrievability, but that participants use their memory differently when making JOLs. RCJs were more accurate than JOLs at predicting future recall for some subsets of items, but the reverse was true for other subsets of items. Finally, eventual recall performance was facilitated when participants made JOLs but not when they made RCJs, suggesting that the JOL task helps to improve people's learning of the items. 相似文献