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11.
This study has 2 objectives: (a) to explore typical paths of cognitive development associated with aging, terminal decline, and dementia and (b) to promote and illustrate an individual-oriented approach to the study of cognitive aging based on longitudinal panel data from a population-based sample (N = 500; age range-sub(T1)= 60-80, where T refers to time) tested at 3 occasions 5 years apart. Results document interindividual differences in multivariate patterns of change. Although cognitive changes generally covary, the present study indicates that subgroups of individuals develop along different paths characterized by selective changes in subsets of cognitive functions. Typical progression of dementia followed a developmental cascade from low declarative memory, via low functioning across all observed cognitive measures, to dementia diagnosis, and finally, death.  相似文献   
12.
Blood-oxygenation-level-dependent signal was measured with functional magnetic resonance imaging in 24 healthy young subjects (12 men and 12 women) during viewing of angry, fearful, and neutral male and female face pictures. Exposure to angry male as opposed to angry female faces activated the visual cortex and the anterior cingulate gyrus significantly more in men than in women. A similar sex-differential brain activation pattern was present during exposure to fearful but not neutral faces. Previous behavioral studies indicate enhanced physiological arousal in men but not in women during exposure to angry male as opposed to female faces, and brain imaging studies have shown that the occipital cortex and the anterior cingulate gyrus are influenced by activity in the autonomic nervous system as well as by visual attention. Hence, we suggest that the elevated occipital and anterior cingulate activation in men during confrontation with other angry and fearful males may reflect enhanced vigilance in a potentially dangerous situation.  相似文献   
13.
Selective sex differences in declarative memory   总被引:4,自引:0,他引:4  
Sex invariance of a six-factor, higher order model of declarative memory (two second-order factors: episodic and semantic memory; and four first-order factors: recall, recognition, fluency, and knowledge) was established for 1,796 participants (35-85 years). Metric invariance of first- and second-order factor loadings across sex was demonstrated. At the second-order level, a female advantage was observed for both episodic and semantic memory. At the first-order level, sex differences in episodic memory were apparent for both recall and recognition, whereas the differences in semantic memory were driven by a female superiority in fluency. Additional tests of sex differences in three age groups (35-50, 55-65, and 70-85 years of age) indicated that the female superiority in declarative memory diminished with advancing age. The factor-specific sex differences are discussed in relation to sex differences in hippocampal function.  相似文献   
14.
Symmetry properties have been shown to determine the perceived complexity of certain patterns. We used a paired-comparison method to obtain judgments of relative complexity for a family of two-dimensional regular patterns called band patterns. Although the complexity of these patterns is well predicted by their symmetry properties we were unable to explain an interaction observed between two of these properties for our experimental patterns. We discuss the implications of our results for two predominant approaches to the perceived complexity of patterns. Neither approach takes into account that the presence of grouping sometimes makes it difficult to perceive a relationship within the pattern that would--were it not for the grouping--simplify it. We conclude that grouping can mask simplicity and that this phenomenon is crucial to the understanding of perceived complexity.  相似文献   
15.
Findings from a study of 563 adolescents’ reactions following a discotheque fire that killed 63 young people in Göteborg in October 1998 are presented. The group answered a questionnaire seven months following the disaster. The questionnaire included the Impact of Event Scale (IES) and the Birleson Depression Self‐Rating Scale (DSRS). The level of trauma was found to be very high, while depression scores were less elevated. A little under a third of the students scored above a clinical cut‐off point (> 35) on the IES, indicating high posttraumatic stress levels. Girls evidenced more depression and traumatic stress reactions than boys. Levels of reactions increased with more closeness (knowing victims personally) and if the adolescents were of non‐Swedish origin.  相似文献   
16.
Cross-sectional differences and longitudinal changes in cognitive functioning in relation to mortality across a 7-year follow-up period, with 3 times of measurement, were examined in a population-based sample of very old adults. The authors also sought to determine whether cause of death (cerebro/cardiovascular disease [CVD]; non-CVD) modified the magnitude of mortality-related cognitive deficits. Cognitive performance was indexed by tests of general cognitive ability, episodic memory, primary memory, verbal fluency, and visuospatial ability. Results indicated cross-sectional differences on all domains of functioning, with persons who would die within 3 years after baseline testing performing more poorly. Longitudinally, greater decrements were observed on all domains for persons who would die after the first follow-up period, as compared with survivors. Cause of death failed to modify the magnitude of the cross-sectional and longitudinal deficits. The pattern of results point to the general nature of this phenomenon.  相似文献   
17.
Deficits in executive functioning and working memory associated with frontal lobe dysfunction are prominent in depression and work-related long-term sick leave (LTSL). This study used functional magnetic resonance imaging (fMRI) to investigate potential differences in brain activation patterns in these conditions. In addition, the function of the hypothalamic-pituitary-adrenal (HPA) axis was examined and compared between groups. Since there is a clear overrepresentation of women in these diagnostic groups, and to ensure a more homogenous sample population, only women were included. To examine the neural correlates of relevant cognitive processes in patients on sick leave >90 days due to work-related LTSL, recently diagnosed patients with major depression Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV criteria, untreated), and healthy controls (n?=?10, each group), a 2-back working memory task and a visual long-term memory task were administered during fMRI scanning. HPA axis functioning was investigated using a diurnal curve of saliva cortisol and a dexamethasone suppression test. Task performance was comparable among the three groups. Multivariate image analysis revealed that both memory tasks engaged a similar brain network in all three groups, including the prefrontal and parietal cortex. During the 2-back task, LTSL patients had significant frontal hypoactivation compared to controls and patients with depression. Saliva cortisol measurements showed a flattening of the diurnal rythmicity in LTSL patients compared to patients with depression and healthy contols. Taken together, these findings indicate that work stress-related LTSL and major depression are dissociable in terms of frontal activation and diurnal cortisol rhythmicity.  相似文献   
18.
Using a person-oriented approach the study examined whether bullying victimization at school continued into cyberspace victimization in a large sample of high school students in Lithuania (N = 1667, 58% girls), age 15-19 (M = 17.29, SD = 0.95). Three forms of traditional bullying (verbal, physical and relational) and seven forms of cyberbullying victimization through cell phones and computers were included in the analysis. The findings revealed that 35% of traditional bullying victims were also bullied in cyberspace. In particular, adolescents who experienced predominantly verbal and relational bullying at school, showed a higher risk of victimization in cyberspace a year later, while this was not observed for predominantly physical forms of traditional bullying. The findings point to the importance of a cross-contextual perspective in studies on stability of bullying victimization.  相似文献   
19.
Refugees have often been exposed to multiple traumas making them prone to mental health problems later. The aim of this study is to describe the prevalence and symptom load of psychiatric disorders in refugees admitted to psychiatric outpatient clinics and to investigate the relationship between multiple exposure to traumatic events, the severity of traumatic symptoms and post-migration stressors. A clinical sample of 61 refugee outpatients from psychiatric clinics in Southern Norway was cross-sectionally examined using three structured clinical interviews (SCID-PTSD, SIDES and MINI) and self-report psychometric instruments (HSCL-25, IES-R). Post-traumatic Stress Disorder (PTSD) was diagnosed in 82% of the patients, while Disorders of Extreme Stress Not Otherwise Specified (DESNOS) was present in 16% of them. Comorbidity was considerable; 64% of the patients had both PTSD and major depression disorder (MDD) and 80% of those who had PTSD had three or more additional diagnoses. Multi-traumatized refugees in outpatient clinics have high prevalence of PTSD, DESNOS, comorbid depression and anxiety disorders. A more severe symptomatology was found in patients diagnosed with both PTSD and DESNOS, than in those diagnosed with only PTSD. Higher rates of unemployment, weak social network and weak social integration were also prevalent in these outpatients, and related to increased psychiatric comorbidity and severity of symptoms. Further research may clarify the existence of a cumulative relationship between pre-resettlement traumas and post-resettlement stressors in the mental health of refugees, which in turn may help to improve therapeutic interventions.  相似文献   
20.
We perceive structure through a process of perceptual organization. Here we report a new perceptual organization phenomenon-the facilitation of visual grouping by global curvature. Observers viewed patterns that they perceived as organized into collections of curves. The patterns were perceptually ambiguous such that the perceived orientation of the patterns varied from trial to trial. When patterns were sufficiently dense and proximity was equated for the predominant perceptual alternatives, observers tended to perceive the organization with the greatest curvature. This effect is tantamount to visual grouping by maximal curvature and thus demonstrates an unprecedented effect of global structure on perceptual organization. We account for this result with a model that predicts the perceived organization of a pattern as function of its nonaccidentality, which we define as the probability that it could have occurred by chance. Our findings demonstrate a novel relationship between the geometry of a pattern and the visual salience of global structure.  相似文献   
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