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151.
Older adults are slower than young adults to think of an item they just saw, that is, to engage or execute (or both) the simple reflective operation of refreshing just-activated information. In addition, they derive less long-term memory benefit from refreshing information. Using functional magnetic resonance imaging (fMRI), we found that relative to young adults, older adults showed reduced refresh-related activity in an area of dorsolateral prefrontal cortex (left middle frontal gyrus, Brodmann's Area 9), but not in other refresh-related areas. This provides strong evidence that a frontal component of the circuit that subserves this basic cognitive process is especially vulnerable to aging. Such a refresh deficit could contribute to poorer performance of older than young adults on a wide range of cognitive tasks.  相似文献   
152.
Evidence suggests that autism is associated with impaired emotion perception, but it is unknown how early such impairments are evident. Furthermore, most studies that have assessed emotion perception in children with autism have required verbal responses, making results difficult to interpret. This study utilized high-density event-related potentials (ERPs) to investigate whether 3-4-year-old children with autism spectrum disorder (ASD) show differential brain activity to fear versus neutral facial expressions. It has been shown that normal infants as young as 7 months of age show differential brain responses to faces expressing different emotions. ERPs were recorded while children passively viewed photos of an unfamiliar woman posing a neutral and a prototypic fear expression. The sample consisted of 29 3-4-year-old children with ASD and 22 chronological age-matched children with typical development. Typically developing children exhibited a larger early negative component (N300) to the fear than to the neutral face. In contrast, children with ASD did not show the difference in amplitude of this early ERP component to the fear versus neutral face. For a later component, typically developing children exhibited a larger negative slow wave (NSW) to the fear than to the neutral face, whereas children with autism did not show a differential NSW to the two stimuli. In children with ASD, faster speed of early processing (i. e. N300 latency) of the fear face was associated with better performance on tasks assessing social attention (social orienting, joint attention and attention to distress). These data suggest that children with ASD, as young as 3 years of age, show a disordered pattern of neural responses to emotional stimuli.  相似文献   
153.
Two studies compared young and older adults' memory for location information after brief intervals. Experiment 1 found that accuracy of intentional spatial memory for individual locations was similar in young and older participants for set sizes of 3 and 6. Both groups also encoded individual locations in relation to the larger configuration of locations. Experiment 2 showed that like young adults, older adults' latency to respond to a test probe in a letter working memory task was negatively influenced by spatial information that was irrelevant to the task. This interference effect indicated preserved incidental memory for spatial information in older adults. Together, these data suggest that initial encoding of spatial information for relatively small numbers of items is largely preserved in healthy older adults and that representations of spatial information persist over short intervals.  相似文献   
154.
Pigeons and humans were trained to discriminate between pictures of three-dimensional objects that differed in global shape. Each pair of objects was shown at two orientations that differed by a depth rotation of 90° during training. Pictures of the objects at novel depth rotations were then tested for recognition. The novel test rotations were 30°, 45°, and 90° from the nearest trained orientation and were either interpolated between the trained orientations or extrapolated outside of the training range. For both pigeons and humans, recognition accuracy and/or speed decreased as a function of distance from the nearest trained orientation. However, humans, but not pigeons, were more accurate in recognizing novel interpolated views than novel extrapolated views. The results suggest that pigeons’ recognition was based on independent generalization from each training view, whereas humans showed view-combination processes that resulted in a benefit for novel views interpolated between the training views.  相似文献   
155.
The effect of attention during adaptation on subsequent negative afterimages was examined. One of 2 overlapped outline figures was attended during a 7-10-s adaptation period. When the figures were readily perceptually segregated (on the basis of color or motion), the subsequent afterimages were initially weaker for the previously attended figure. This effect was confirmed by demonstrations that the onset of a single afterimage was delayed when an afterimage inducer was attended during adaptation compared with when a central digit stream or an overlapped (brightness-balanced) figure that did not generate an afterimage was attended. The attention effect was further confirmed using a criterion-independent (dot-integration) paradigm. The fact that selective attention during adaptation weakened or delayed afterimages suggests that attention primarily facilitates the adaptation of polarity-independent processes that modulate the visibility of afterimages rather than facilitating the adaptation of polarity-selective processes that mediate the formation of afterimages.  相似文献   
156.
This article provides background information and an overview on Resources for Enhancing Alzheimer's Caregiver Health (REACH) a multisite intervention trial for caregivers of persons with Alzheimer's disease designed to reduce caregiver burden and depression. REACH is the largest randomized controlled clinical trial to date, involving 1,222 caregiver and care recipient dyads recruited from 6 different sites in the United States. The authors describe the design of the study, summarize the interventions implemented at each site, and provide an overview of the 4 articles in this special section.  相似文献   
157.
The Resources for Enhancing Alzheimer's Cargiver Health (REACH) project was designed to test promising interventions for enhancing family caregiving for persons with dementia. The purpose of this article is to describe the research design, interventions, and outcome measures used in REACH and to characterize the sample recruited for the study. Nine interventions and 2 control conditions were implemented at 6 sites; 1,222 dyads were randomly assigned to an intervention or a control condition. The caregiver sample was 18.6% male with an average age of 62.3 years (56% Caucasian, 24% Black, and 19% Hispanic). Caregivers reported high levels of depressive symptoms and moderate burden. Care recipients were older, with a mean age of 79, and were moderately to severely impaired with mean Mini-Mental State Exam scores of 13/30.  相似文献   
158.
The American Journal of Psychoanalysis -  相似文献   
159.
The main task of generativity–stagnation, Erik Erikson's seventh stage of normative psychosocial development, is to establish and guide the next generation through one's acts of care. Five statuses, or prototypic styles of resolving the issues of this stage, determined using a new, semistructured interview measure, are defined using combinations of (1) an individual's level of involvement, or active concern for the growth of the self and others; and (2) an individual's inclusivity, or scope of caregiving concern. Construct validation efforts sought concurrent validity using two different scale measures of generativity, and discrimination between status profiles using the NEO Personality Inventory and Loevinger's Sentence Completion Test of ego development. Results generally support the new status model and point to areas of conceptual convergence and divergence between this approach and other generativity measures.  相似文献   
160.
This study examined the psychological consequences and secondary stressors associated with death of a parent. The sample (N = 116) consisted of 26 youths who had lost a parent to homicide, 45 youths who had lost a parent to natural death, and 45 nonbereaved youths. Youngsters completed face-to-face interviews, while their guardians completed measures assessing the children's functioning. Results based on both child and guardian reports indicated that parental death was associated with an increase in secondary stressors, regardless of the mode of death. Findings based on guardian reports also revealed that parental death was related to increased internalizing distress, and that parental death due to homicide was related to increased externalizing distress. Furthermore, secondary stressors mediated the parental death–child distress relation such that parental death led to an increase in stressors, which in turn led to increased child distress. Implications for secondary and tertiary preventive interventions are discussed.  相似文献   
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