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221.
222.
Recent studies of adults have found evidence for consolidation effects in the acquisition of novel words, but little is known about whether such effects are found developmentally. In two experiments, we familiarized children with novel nonwords (e.g., biscal) and tested their recognition and recall of these items. In Experiment 1, 7-year-olds were then retested on either the same day or the following day to examine changes in performance after a short delay compared with a longer delay that included sleep. Experiment 2 used two age groups (7- and 12-year-olds), with all participants being retested 24h later. The 12-year-olds accurately recognized the novel nonwords immediately after exposure, as did the 7-year-olds in Experiment 2 (but not in Experiment 1), suggesting generally good initial rates of learning. Experiment 1 revealed improved recognition of the novel nonwords after both short (3- to 4-h) and longer (24-h) delays. In contrast, recall was initially poor but showed improvements only when children were retested 24h later, not after a 3- to 4-h delay. Similar improvements were observed in both age groups despite better overall performance in 12-year-olds. We argue that children, like adults, exhibit offline consolidation effects on the formation of novel phonological representations.  相似文献   
223.
In the present study, we showed that a representational disorder for words can dissociate from both representational neglect for objects and neglect dyslexia. This study involved 14 brain-damaged patients with left unilateral spatial neglect and a group of normal subjects. Patients were divided into four groups based on presence of left neglect dyslexia and representational neglect for non-verbal material, as evaluated by the Clock Drawing test. The patients were presented with bisection tasks for words and lines. The word bisection tasks (with words of five and seven letters) comprised the following: (1) representational bisection: the experimenter pronounced a word and then asked the patient to name the letter in the middle position; (2) visual bisection: same as (1) with stimuli presented visually; and (3) motor bisection: the patient was asked to cross out the letter in the middle position. The standard line bisection task was presented using lines of different length. Consistent with the literature, long lines were bisected to the right and short lines, rendered comparable in length to the words of the word bisection test, deviated to the left (crossover effect). Both patients and controls showed the same leftward bias on words in the visual and motor bisection conditions. A significant difference emerged between the groups only in the case of the representational bisection task, whereas the group exhibiting neglect dyslexia associated with representational neglect for objects showed a significant rightward bias, while the other three patient groups and the controls showed a leftward bisection bias. Neither the presence of neglect alone nor the presence of visual neglect dyslexia was sufficient to produce a specific disorder in mental imagery. These results demonstrate a specific representational neglect for words independent of both representational neglect and neglect dyslexia.  相似文献   
224.
The current study provides naturalistic data documenting the pathways-to-care to vocational services for 155 veterans who were receiving some form of mental health care from the Veterans Health Administration and had a vocational need but were not currently enrolled in vocational services. Of the participants, 94.2% had recognized their vocational need, 80.6% reported that they or someone else had sought help to alleviate the need, and 77.4% had previously received some form of vocational services. The median length of the participants' vocational need was more than 4.2 years. Delays associated with recognition, help-seeking, and treatment entry all contributed to the overall delay in entering appropriate care. Filtering factors associated with quicker recognition, seeking help, and receiving services included diagnosis, level of disability, type of vocational need, and support from primary providers, family, and friends. The results provide information for designing interventions to improve service entry by adults with mental health problems and vocational needs.  相似文献   
225.
The role of epigenetic mechanisms in control of gene expression during mammalian development is well established. Associations between specific DNA or histone modifications and numerous neurodevelopmental and neurodegenerative disorders implies significant consequences of epigenetic dysregulation in both the developing and mature brain, the latter of which is the general focus of this review. Accumulating evidence suggests that epigenetic changes are involved in normal cognitive processes in addition to neurological and psychiatric disorders. Recent investigations into the regulation of epigenetic modifications in the adult brain have revealed novel and surprisingly dynamic mechanisms for controlling learning and memory-related behaviors as well as long-term synaptic plasticity. DNA methylation and histone acetylation have also been implicated in the modulation of basal synaptic transmission and the balance between excitation and inhibition in various brain regions. Studies have begun to uncover some of the alterations in gene expression that appear to mediate many of these effects, but an understanding of the precise mechanisms involved is still lacking. Nevertheless, the fundamental importance of epigenetic processes in influencing neuronal activity is becoming increasingly evident.  相似文献   
226.
Gender segregation is often explained by children being interested in interacting with other children who behave similarly to themselves. Children??s beliefs about girls and boys (i.e., their gender cognitions) may also play a role in gender segregation, but this idea has received little attention. In this study, we proposed a model of gender segregation that included similarity on gender-typed behavioral qualities (e.g., rough and tumble play) and gender cognitions concerning perceived similarity to same-gender others, and we assessed whether this more comprehensive heuristic model predicted observed peer interactions in young U.S. children (n?=?74; M age = 51 m; middle-class families). A multi-method design was employed including observations of behavior and child reports of gender cognitions. Support was found for the linkages proposed in this comprehensive model for boys; partial support was found for girls. Specifically, the inclusion of gender cognitions was supported for both genders: gender cognitions about perceived similarity related to interactional partner choices for both girls and boys, and accounted for variance in observed partner choices even after behavioral similarity was included in the model. The traditional link concerning behavioral similarity on rough-and-tumble play predicted boys?? but not girls?? interactions. The findings extend knowledge about the role of social cognitions in social behavior, and are consistent with ideas proposed by gender schema theory and other constructivist theories.  相似文献   
227.
Two experiments examined the hypothesis that developing visual attentional mechanisms influence infants' Visual Short-Term Memory (VSTM) in the context of multiple items. Five- and 10-month-old infants (N = 76) received a change detection task in which arrays of three differently colored squares appeared and disappeared. On each trial one square changed color and one square was cued; sometimes the cued item was the changing item, and sometimes the changing item was not the cued item. Ten-month-old infants exhibited enhanced memory for the cued item when the cue was a spatial pre-cue (Experiment 1) and 5-month-old infants exhibited enhanced memory for the cued item when the cue was relative motion (Experiment 2). These results demonstrate for the first time that infants younger than 6 months can encode information in VSTM about individual items in multiple-object arrays, and that attention-directing cues influence both perceptual and VSTM encoding of stimuli in infants as in adults.  相似文献   
228.
Oregon Violent Death Reporting System data were linked with Veterans Affairs (VA) administrative data to identify and describe veterans who completed suicide in Oregon from 2000 to 2005 (n = 968), and to describe their VA health care utilization in the year prior to death. Twenty-two percent had received health care in the VA system. Of these, 57% did not have mental health diagnoses and 58% had not seen mental health professionals. A larger proportion of those who accessed care were VA-enrolled and received service-connected disability benefits. Fifty-five veterans were hospitalized during the year prior to death. Of these, 33% completed suicide within 30 days of a hospitalization. Further development of suicide prevention strategies for veterans in the community, including general medical treatment settings, is indicated.  相似文献   
229.
Headache is the most common neurological symptom presenting to general practitioners (GPs). Identifying factors predicting outcome in patients consulting their GPs for headache may help GPs with prognosis and choose management strategies which would improve patient care. We followed up a cohort of patients receiving standard medical care, recruited from 18 general practices in the South Thames region of England, approximately 9 months after their initial participation in the study. Of the baseline sample (N=255), 134 provided both full baseline and follow-up data on measures of interest. We determined associations between patients' follow-up scores on the Headache Impact Test-6 and baseline characteristics (including headache impact and frequency scores, mood, attributions about psychological/medical causes of their headaches, satisfaction with GP care and illness perceptions). Greater impact and stronger beliefs about the negative consequences of headaches at baseline were the strongest predictors of poor outcome at follow-up.  相似文献   
230.
The serial reaction time (SRT) task is a simple procedure in which participants produce differentiated responses to each of a series of stimuli presented at varying locations. Learning about stimulus order is revealed through decreased latencies for structured versus randomized sequences. Although widely used with humans and well suited to nonhumans, this paradigm is little used in comparative research. In the present article, we describe an SRT procedure that uses colored circles as stimuli, a circular layout of locations, and symmetrical joystick deflections as responses. In two experiments, we showed that four rhesus macaques (Macaca mulatta) learned to track sequences up to eight items long, with three animals showing faster responding to repeating sequences than to randomized versions. After extended training, these participants also showed evidence of faster responding at all positions within repeating sequences. This method minimizes response effort, equates effort and travel distance across stimulus locations, and is applicable to any joystick-capable species.  相似文献   
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