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981.
A meaningful interaction with our environment relies on the ability to focus on relevant sensory input and to ignore irrelevant information, i.e. top-down control and attention processes are employed to select from competing stimuli following internal goals. In this, the demands for the recruitment of top-down control processes depend on the relative perceptual salience of the competing stimuli. In the present functional magnetic resonance imaging (fMRI) study, we investigated the recruitment of top-down control processes in response to varying degrees of control demands in the auditory modality. For this purpose, we tested 20 male and 20 female subjects with a dichotic listening paradigm, in which the relative perceptual salience of two simultaneously presented stimuli was systematically manipulated by varying the inter-aural intensity difference (IID) and asking the subjects to selectively attend to either ear. The analysis showed that the interaction between IID and attentional direction involves two networks in the brain. A fronto-parietal network, including the pre-supplementary motor area, anterior cingulate cortex, inferior frontal junction, insula and inferior parietal lobe, was recruited during cognitively demanding conditions and can thus be seen as a top-down cognitive control network. In contrast, a second network including the superior temporal and the post-central gyri was engaged under conditions with low cognitive control demands. These findings demonstrate how cognitive control is achieved through the interplay of distinct brain networks, with their differential engagement determined as a function of the level of competition between the sensory stimuli.  相似文献   
982.
The present study examined whether middle-aged participants, like young adults, learn movement patterns by preparing and executing integrated sequence representations (i.e., motor chunks) that eliminate the need for external guidance of individual movements. Twenty-four middle-aged participants (aged 55–62) practiced two fixed key press sequences, one including three and one including six key presses in the discrete sequence production task. Their performance was compared with that of 24 young adults (aged 18–28). In the middle-aged participants motor chunks as well as explicit sequence knowledge appeared to be less developed than in the young adults. This held especially with respect to the unstructured 6-key sequences in which most middle-aged did not develop independence of the key-specific stimuli and learning seems to have been based on associative learning. These results are in line with the notion that sequence learning involves several mechanisms and that aging affects the relative contribution of these mechanisms.  相似文献   
983.
The present study investigated verbal and spatial working memory (WM) functioning in individuals with the neuro-developmental disorder Williams syndrome (WS) using WM component tasks. While there is strong evidence of WM impairments in WS, previous research has focused on short-term memory and has neglected assessment of executive components of WM. There is a particular lack of consensus concerning the profile of verbal WM functioning in WS. Here, WS participants were compared to typically developing participants matched for (1) verbal ability and (2) spatial ability (N = 14 in each of the 3 groups). Individuals with WS were impaired on verbal WM tasks, both those involving short-term maintenance of information and executive manipulation, in comparison to verbal-matched controls. Surprisingly, individuals with WS were not impaired on a spatial task assessing short-term maintenance of information in memory (remembering spatial locations) compared to spatial-matched controls. They were, however, impaired on a spatial executive WM task requiring the manipulation of spatial information in memory. The present study suggests that individuals with WS show WM impairments that extend to both verbal and spatial domains, although spatial deficits are selective to executive aspects of WM function.  相似文献   
984.
Both working and immediate memories were assessed every 4h by specific short-term memory tasks over sustained wakefulness in 12 patients with obstructive sleep apnea and hypopnea syndrome (OSAHS) and 10 healthy controls. Results indicated that OSAHS patients exhibited lower working memory performances than controls on both backward digit span and complex Sternberg tasks. Speed and accuracy on Sternberg tasks were affected by memory load in both groups. However, immediate memory was not impaired in OSAHS patients. Diurnal and nocturnal SaO(2) were correlated with speed and accuracy high-speed memory scanning performance on Sternberg tasks in patients. These results suggest specific working memory deficits associated with OSAHS over sustained wakefulness with a possible deficiency in the central executive responsible for the higher information processing, in addition to a potentially insufficient storage capacity. Among OSAHS patients, working memory ability involved in high-speed memory scanning may be impaired by chronic hypoxemia.  相似文献   
985.
The main purpose of this study was to explore the dimensionality of the borderline personality disorder in nonclinical young adults by means of the Borderline Personality Questionnaire (BPQ; Poreh et al., 2006). We also studied the phenotypic expression of the borderline personality traits as a function of participants' gender and age, and the relationship between BPQ subscales and measures of depressive symptoms, anxiety, stress, hallucinatory predisposition, and paranoid ideation. The sample comprised 809 young adults, 562 (69.5%) were women, with a mean age of 20.2 years (SD = 2.9). The results indicate that the BPQ self-report has adequate psychometric properties. The levels of internal consistency for the BPQ subscales ranged between .78 and .93. Analysis of the internal structure of the BPQ subscales yielded a one-dimensional solution. In contrast, second-order principal components analysis at the item level yielded a five-dimensional solution. Likewise, statistically significant differences in the mean scores of the borderline personality traits as a function of participants' gender and age were found. The BPQ subscales correlated significantly with measures of depression, anxiety, stress, paranoid ideation, and hallucinatory predisposition. These results help to improve our understanding of the dimensional structure of the borderline personality in the general population. Future research should continue to identify participants who are at risk for the development of borderline personality disorder and facilitating the development of early detection and prevention programs.  相似文献   
986.
This study examined the associations between infant and childhood growth and severe personality disorders. Among 4,689 men and 4,200 women of the Helsinki Birth Cohort Study 1934-1944, 81 men and 68 women had been hospitalized with an ICD (-8, -9, -10) diagnosis of personality disorder in adulthood. Among men, slower gain in BMI between birth and 6 months, faster gain in weight and BMI between 6 months and 1 year, and slower gains in them between 7 and 11 years of age predicted an increased risk of hospitalization for personality disorders. Thinness at 6 months and again at 11 years also showed significant association with personality disorders among men. Among women, slower gain in height between 2 and 7 years predicted hospitalization for personality disorders. Our findings show the importance of early growth as a vulnerability factor of personality disorders severe enough to justify hospitalization.  相似文献   
987.
Over the last decade or so, the Internet has become a privileged media for advertisement. Despite this increase in popularity, several studies suggested that Internet users ‘avoid’ looking at ads (what is often referred to as the banner blindness phenomena). This conclusion, however, rests mostly on indirect evidence that participants do not remember the ad content. Therefore, it is unclear whether participants actually fixated the ads and how their gaze behaviour is related to memory for the ad. In the present study, we investigated whether Internet users avoid looking at ads inserted on a non‐search website using an analysis of eye movements, and if the ad content is kept in memory. Our results show that most participants fixate the ads at least once during their website visit. Moreover, even though the congruency between the ad and the editorial content had no effect on fixation duration on the ad, congruent ads were better memorised than incongruent ads. This study provides a novel and systematic method for assessing the processing and retention of advertisements during a website visit. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   
988.
Due to the risk of fetal anomaly, pregnant women of advanced maternal age are given the option to undergo amniocentesis. In our study we aimed to describe couples’ decision-making process regarding amniocentesis, and assess whether it is influenced by marital intimacy and men’s participation in genetic counseling. During pregnancy, 112 couples answered the Personal Assessment of Intimacy in Relationships questionnaire and scales regarding the decision to undergo amniocentesis. Most couples shared and reached an agreement regarding this decision. Higher levels of marital engagement and communication, but not men’s participation, were associated with higher agreement, influence, and decision-sharing. Clinical implications are discussed.  相似文献   
989.
We address the question as to whether judgmental overconfidence, as assessed by probability miscalibration, is related to positive illusions about the self. We first demonstrate that judgmental overconfidence measured with interval production procedures can be considered a trait, due to correlations observed in miscalibration scores in two sets of general‐knowledge questions of varying difficulty administered at different times. In addition, the hard‐easy effect operated in different ways on overprecision and self‐placement of one's performance relative to others: The more difficult the calibration task, the greater the over precision but the greater the under placement of one's performance. Finally, there was no evidence that miscalibration was related to dispositional optimism and self‐efficacy. A second study extended these results by including further measures of disposition to experience positive illusions such as unrealistic optimism, a general tendency to consider oneself “better‐than‐average,” and two indexes of dispositional perception of control. The positive illusion measures showed considerable inter‐correlations, but did not correlate with miscalibration on the interval production task, and correlated negatively with optimism concerning societal risks. A final study replicated this pattern of findings, but showed that disposition to positive illusions did predict miscalibration on the same questions measured with a probability evaluation technique. Our research demonstrates that “overconfidence” is not a unitary construct, but a series of overlapping ones. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   
990.
Theoretical perspectives and research in sociology, anthropology, sociolinguistics, and cultural psychology converge in recognizing the significance of children's time spent in various activities, especially in the family context. Knowing how children's time is deployed, however, only gives us a partial answer to how children acquire competence; the other part must take into account the culturally constructed meanings of activities, from the perspective of those who organize and direct children's daily lives. In this article, we report on a study of children's routine daily activities and on the meanings that parents attribute to them in six Western middle-class cultural communities located in Italy, The Netherlands, Poland, Spain, Sweden, and the United States (N = 183). Using week-long time diaries kept by parents, we first demonstrate similarities as well as significant differences in children's daily routines across the cultural samples. We then present brief vignettes--"a day in the life" --of children from each sample. Parent interviews were coded for themes in the meanings attributed to various activities. Excerpts from parent interviews, focusing on four major activities (meals, family time, play, school- or developmentally related activities), are presented to illustrate how cultural meanings and themes are woven into parents' organization and understanding of their children's daily lives. The results of this mixed-method approach provide a more reliable and nuanced picture of children's and families' daily lives than could be derived from either method alone.  相似文献   
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