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861.
Patterns of friendship among girls with and without attention-deficit/hyperactivity disorder 总被引:5,自引:0,他引:5
Examined patterns of friendship participation, stability, and quality among previously unfamiliar, ethnically diverse girls with attention-deficit/hyperactivity disorder (ADHD; n = 140) and comparison (n = 88) girls, aged 6–12 years, who attended 5-week naturalistic summer camps. Each girl completed sociometric nominations during Weeks 1, 3, and 5 of the camps; friendships were indexed by examining patterns of reciprocal nominations. At each assessment point, girls with ADHD had fewer mutual friends and were more likely to have no friends. Girls with Combined-type ADHD exhibited difficulties maintaining friendships from the beginning to middle of camp, whereas girls with Inattentive-type ADHD demonstrated poor friendship stability from the middle to end of camp. In general, girls with ADHD had higher levels of negative relationship features—including conflict and relational aggression—than did comparison girls, but levels of positive relationship features did not differ across subgroups. Friendship status predicted positive and negative peer regard, controlling for Verbal IQ and diagnostic status. Overall, although girls with ADHD were able to make friends to some extent, they differed from comparison girls in terms of the likelihood of doing so, the ability to maintain the friendships that they did form, and the levels of negative features found in their friendships. 相似文献
862.
This study investigated the effect of noise masking on on-line syntactic processing. Ninety college students were tested on measures of working memory and on-line sentence comprehension. Subjects were divided equally into three listening conditions: no noise masking, -3 dB signal-to-noise ratio (S:N), -4.5 dB S:N. The auditory moving windows (AMW) paradigm was used to measure on-line sentence processing. In the AMW paradigm, subjects pressed a button for the successive presentation of each phrase in two types of sentences (syntactically simple and complex), and listening times were recorded for each phrase. Previous studies have shown that the verb in the more complex sentence type is the most capacity demanding portion of the sentence. Listening times were longer overall with increased noise masking, and listening times were longer overall at the verb of the harder sentence type. However, the increase at the verb was not larger with increased noise masking. All three groups showed similar effects of syntactic structure in the on-line data. The on-line syntactic effects were not due to problems in word recognition. Correlational analyses did not indicate a relationship between the increase in processing time at the capacity demanding region of the harder sentence types and any of the measures of working memory capacity in any of the three listening conditions. Results indicate that on-line sentence processing is not affected by noise masking if lexical access (e.g., word recognition) remains intact. 相似文献
863.
Neuroimaging can now provide information about structure and function. Despite new and improved neuroimaging technologies applicable to the newborn, predictions about later cognition, learning, social and emotional behavior, and neuromuscular capabilities, based on images of a fetus inside or a newborn outside the womb, are fraught with difficulties that go beyond technical ones. The interpretation of neuroimages may be necessary but it is not sufficient for decision-making related to the withholding or withdrawing of medical support for neonates. As the explanatory reach of neuroimaging increases, there will still need to be consideration of ethical issues as they relate to the best interests of the neonate and the neonate's parents, the quality of life of the neonate and non-beneficial treatment. Once this is appreciated, the boundary between the technical and the ethical will be less often disputed. 相似文献
864.
A meta-analysis in the form of Brinley plots was conducted on the mean reaction times of HIV+ and HIV- groups. HIV+ reaction times were regressed on HIV- reaction times across 122 task conditions from 29 studies, producing a highly linear function (r(2) = .94), with a slope b = 1.039, which was not significantly different than b = 1.00. Asymptomatic and symptomatic HIV+ reaction times were also separately regressed on HIV- reaction times across 67 task conditions from 13 studies. Both functions were highly linear (r(2) = .97 and.90 respectively), with slopes of 1.034 and 1.117 respectively. Only the slope for symptomatic HIV+ groups was significantly larger than b = 1.00, suggesting a modest generalized slowing of cognition in these adults. 相似文献
865.
Huber DE Shiffrin RM Lyle KB Quach R 《Journal of experimental psychology. Learning, memory, and cognition》2002,28(6):1120-1136
D. E. Huber, R. M. Shiffrin, K. B. Lyle, and K. I. Ruys (2001) tested two-alternative, forced-choice (2-AFC) perceptual identification in a short-term priming task. For repetition priming, passive viewing of primes resulted in a preference to choose repeated words, but actively responding to primes resulted in a preference against choosing repeated words. These results were explained with a computational model, responding optimally with unknown sources of evidence (ROUSE), using the offsetting mechanisms of source confusion and discounting. An analysis of ROUSE revealed conditions under which discounting efficacy should diminish, causing a preference for primed words even with active prime processing. Two new studies confirm 2 such conditions: very short target flash durations and very low similarity between primes and primed choice words. These a priori predictions contrast with the a posteriori data fits of a multinomial model developed by R. Ratcliff and G. McKoon (2001). 相似文献
866.
Attentional control: brief and prolonged 总被引:3,自引:0,他引:3
LaBerge D 《Psychological research》2002,66(4):220-233
The attention system can be viewed as a collection of modules each of which contains two components: the expression of attention and the controlling operations that produce that expression. Current theories place sites of attentional control in the anterior cortex and sites of expression in the posterior cortex. Attention to a particular location or appearance of an object is itself controlled by instruction from a supervisory system, by the pointing of an arrow cue, and by bottom-up abrupt onsets of stimuli. The control of attention is regulated by cognitive activities such a cognitive load, error monitoring, and current goals. A new development of the triangular circuit theory, together with supporting data, suggest the existence of two modes of activity in columns of attentional expression: brief enhancement of pulse processing that selects information, and prolonged fast oscillations that sustain attention during preparatory and maintenance attention. It is proposed that the direct pathway of the triangular circuit controls the selection of information in the brief attention mode while the indirect pathway through the thalamus controls the production of fast oscillations in the prolonged attention mode. 相似文献
867.
Maestripieri D Ross SK Megna NL 《Journal of comparative psychology (Washington, D.C. : 1983)》2002,116(3):219-227
This study investigated mother-infant interactions in lowland gorillas (Gorilla gorilla gorilla) with particular focus on the relative role of mothers and infants in creating situations that are potentially conducive to infant social learning. Eleven gorilla mother-infant dyads were focally observed in weekly 1-hr sessions for 12 months. Spatial relationships were affected by age as well as by ambient temperature. Although the youngest infant was encouraged by its mother to walk and climb, mothers showed little or no encouragement in other contexts. In contrast, infants were quite interested in their mothers' activities, on some occasions repeated their mother's behavior, and actively encouraged their mothers to share food, play, or follow them. These findings suggest that gorilla infants are more active than their mothers in creating situations that are potentially conducive to the acquisition of knowledge or skills. 相似文献
868.
Hempel AG Kownacki R Malin DH Ozone SJ Cormack TS Sandoval BG Leinbach AE 《Behavioral sciences & the law》2002,20(5):507-522
An archival study was performed in a maximum security forensic hospital to evaluate the effects of a total ban on smoking and all tobacco products. One hundred and forty patients were characterized as nonsmokers or light, moderate or heavy smokers. Patient records for the four weeks prior to the ban were compared with their records for the four weeks subsequent to the ban. Numbers of sick calls, total disruptive behaviors and verbal aggression declined markedly and significantly following the ban in those patients previously classified as moderate or heavy smokers. Weight increased significantly, but almost equally regardless of previous smoking status. Patients, and eventually staff, tolerated the smoking ban without significant negative effects. Patients relied very little on treatment modalities to alleviate nicotine withdrawal. Pre-ban apprehension by staff and patients dissipated with time after the smoking ban started. 相似文献
869.
Many researchers have hypothesized relationships between personality disorders and gender role (i.e., masculinity and femininity). However, research has not addressed if people who are masculine or feminine more often meet the criteria for personality disorders. The present study examined whether college students (N = 665, 60% women) higher in masculinity or femininity more often exhibited features of the 10 DSM-IV personality disorders. Feminine men exhibited more features of all the personality disorders except antisocial. Dependent traits were associated with higher femininity and lower masculinity. Antisocial traits were associated with masculinity. Both men and women who typically behaved consistent with their gender had more narcissistic and histrionic features, whereas participants who typically behaved unlike their gender had more features of the Cluster A personality disorders. 相似文献
870.
The authors compare older adults' lexical-decision data with younger adults' data reported in P. Allen, A. F. Smith, et al. (2002). On the basis of their work, it was proposed that consistent-case wordswould be processed by the faster holistic (magnodominated) stream, but that mixed-case words would be processed by the slower analytic (interblob-dominated or blob-dominated) steams. Hue mixing was predicted to have no effect on consistent-case performance, but mixed-hue/mixed-case words were predicted to be recognized faster than monochrome/mixed-case words. Younger adults showed the predicted results, but older adults did not. These results suggest that holistic central processes are maintained, but that older adults exhibited an analytic decrement 相似文献