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221.
We assessed the relationship between brain structure and function in 10 individuals with specific language impairment (SLI), compared to six unaffected siblings, and 16 unrelated control participants with typical language. Voxel-based morphometry indicated that grey matter in the SLI group, relative to controls, was increased in the left inferior frontal cortex and decreased in the right caudate nucleus and superior temporal cortex bilaterally. The unaffected siblings also showed reduced grey matter in the caudate nucleus relative to controls. In an auditory covert naming task, the SLI group showed reduced activation in the left inferior frontal cortex, right putamen, and in the superior temporal cortex bilaterally. Despite spatially coincident structural and functional abnormalities in frontal and temporal areas, the relationships between structure and function in these regions were different. These findings suggest multiple structural and functional abnormalities in SLI that are differently associated with receptive and expressive language processing.  相似文献   
222.
To understand the neural basis of human speech control, extensive research has been done using a variety of methodologies in a range of experimental models. Nevertheless, several critical questions about learned vocal motor control still remain open. One of them is the mechanism(s) by which neurotransmitters, such as dopamine, modulate speech and song production. In this review, we bring together the two fields of investigations of dopamine action on voice control in humans and songbirds, who share similar behavioral and neural mechanisms for speech and song production. While human studies investigating the role of dopamine in speech control are limited to reports in neurological patients, research on dopaminergic modulation of bird song control has recently expanded our views on how this system might be organized. We discuss the parallels between bird song and human speech from the perspective of dopaminergic control as well as outline important differences between these species.  相似文献   
223.
Researchers continue to debate the role of self-esteem in aggression, but research has shown a consistent association between narcissism and aggression in adults and adolescents [e.g., Barry et al., 2007; Bushman and Baumeister, 1998; Stucke, 2007]. The primary aim of the current study was to examine whether locus of control (LOC) moderated the relation between self-perception variables (i.e., self-esteem and narcissism) and aggression in adolescents. Participants were 174 youth (145 males, 26 females) between the ages of 16 and 19 who were enrolled in a voluntary residential program for youth who have dropped out of school. The results showed that LOC moderated the association between self-esteem and aggression such that low self-esteem was associated with higher levels of aggression for individuals with an external LOC. Contrary to expectations, LOC failed to moderate the narcissism-aggression relation. The implications of this study for understanding how self-perception is related to adolescent aggression are discussed.  相似文献   
224.
We describe a computational model to explain a variety of results in both standard and false recognition. A key attribute of the model is that it uses plausible semantic representations for words, built through exposure to a linguistic corpus. A study list is encoded in the model as a gist trace, similar to the proposal of fuzzy trace theory (Brainerd & Reyna, 2002), but based on realistically structured semantic representations of the component words. The model uses a decision process based on the principles of neural synchronization and information accumulation. The decision process operates by synchronizing a probe with the gist trace of a study context, allowing information to be accumulated about whether the word did or did not occur on the study list, and the efficiency of synchronization determines recognition. We demonstrate that the model is capable of accounting for standard recognition results that are challenging for classic global memory models, and can also explain a wide variety of false recognition effects and make item-specific predictions for critical lures. The model demonstrates that both standard and false recognition results may be explained within a single formal framework by integrating realistic representation assumptions with a simple processing mechanism.  相似文献   
225.
There are twice as many suicides as homicides in the United States, and the suicide rate is rising. Suicides increased 12% between 1999 and 2009. Mental health professionals often treat suicidal patients, and suicide occurs even among patients who are seeking treatment or are currently in treatment. Despite these facts, training of most mental health professionals in the assessment and management of suicidal patients is surprisingly limited. The extant literature regarding the frequency with which mental health professionals encounter suicidal patients is reviewed, as is the prevalence of training in suicide risk assessment and management. Most importantly, six recommendations are made to address the longstanding insufficient training within the mental health professions regarding the assessment and management of suicidal patients.  相似文献   
226.
Preschoolers who explore objects haptically often fail to recognize those objects in subsequent visual tests. This suggests that children may represent qualitatively different information in vision and haptics and/or that children’s haptic perception may be poor. In this study, 72 children (2½-5 years of age) and 20 adults explored unfamiliar objects either haptically or visually and then chose a visual match from among three test objects, each matching the exemplar on one perceptual dimension. All age groups chose shape-based matches after visual exploration. Both 5-year-olds and adults also chose shape-based matches after haptic exploration, but younger children did not match consistently in this condition. Certain hand movements performed by children during haptic exploration reliably predicted shape-based matches but occurred at very low frequencies. Thus, younger children’s difficulties with haptic-to-visual information transfer appeared to stem from their failure to use their hands to obtain reliable haptic information about objects.  相似文献   
227.
The purpose of the present study was to see if 7-10-year-old socially anxious children (n = 26) made systematic errors in identifying and sending emotions in facial expressions, paralanguage, and postures as compared with the more random errors of children who were inattentive-hyperactive (n = 21). It was found that socially anxious children made more errors in identifying anger and fear in children's facial expressions and anger in adults' postures and in expressing anger in their own facial expressions than did their inattentive-hyperactive peers. Results suggest that there may be systematic difficulties specifically in visual nonverbal emotion communication that contribute to the personal and social difficulties socially anxious children experience.  相似文献   
228.
We describe an ontology of philosophy that is designed to aid navigation through philosophical literature, including literature in the form of encyclopedia articles and textbooks and in both printed and digital forms. The ontology is designed also to serve integration and structuring of data pertaining to the philosophical literature, and in the long term also to support reasoning about the provenance and contents of such literature, by providing a representation of the philosophical domain that is oriented around what philosophical literature is about.  相似文献   
229.
Categories are learned and used in a variety of ways, but the research focus has been on classification learning. Recent work contrasting classification with inference learning of categories found important later differences in category performance. However, theoretical accounts differ on whether this is due to an inherent difference between the tasks or to the implementation decisions. The inherent-difference explanation argues that inference learners focus on the internal structure of the categories—what each category is like—while classification learners focus on diagnostic information to predict category membership. In two experiments, using real-world categories and controlling for earlier methodological differences, inference learners learned more about what each category was like than did classification learners, as evidenced by higher performance on a novel classification test. These results suggest that there is an inherent difference between learning new categories by classifying an item versus inferring a feature.  相似文献   
230.
The present study examined the flexibility with which people can adopt different category schemes in the spatial domain. In a location memory task, participants viewed and estimated the locations of four kinds of objects that were spatially grouped by object identity. This identity-based arrangement was either congruent or incongruent with the perceptually based, geometric categories that have been reported in previous research. Four experiments examined the conditions under which these different category schemes are used to inform estimates of locations. The results showed that use of identity information depended on the number of objects to be remembered during a trial: When one or two objects were remembered at a time, only geometric categories affected estimates, but when four objects were to be remembered, both geometric categories and identity groupings affected estimates. As memory load increases, participants rely on additional sources to inform their estimates of location.  相似文献   
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