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851.
Tankard CF Waldstein SR Siegel EL Holder LE Lefkowitz D Anstett F Katzel LI 《Brain and cognition》2003,52(1):70-78
Asymmetric resting blood flow in prefrontal and hemispheric regions, assessed by single photon emission computed tomography (SPECT), was examined as a potential biological marker for enhanced trait and state anxiety in 30 older men (ages 55-81). Average and asymmetric perfusion in dorsolateral, medial, and orbital regions of the prefrontal lobes was also assessed. Results indicated a significant association between lower levels of resting dorsolateral blood flow and greater state anxiety responses to a series of stressful provocations (measured on a separate occasion). A significant curvilinear (U-shaped) relation between asymmetric dorsolateral perfusion and state anxiety was also identified; increased asymmetric blood flow favoring either the right or the left dorsolateral region related to higher levels of state anxiety. However, this association was attenuated by age and systolic blood pressure. Resting perfusion in the dorsolateral region may represent a more reliable biological marker for state anxiety than trait anxiety in older men. 相似文献
852.
Shanks DR Wilkinson L Channon S 《Journal of experimental psychology. Learning, memory, and cognition》2003,29(2):248-261
Exposure to a repeating sequence of target stimuli in a speeded localization task can support both priming of sequence-consistent responses and recognition of sequence components. In 3 experiments with both deterministic and probabilistic sequences, the authors used a novel procedure in which measures or priming and recognition were taken concurrently and asked whether these measures can be dissociated. In all of these experiments, both measures were above chance at the group level and no evidence of dissociation was found. Item-level analyses of the data in Experiment 3 did reveal dissociations in that (a) recognition judgments were affected by response speed independently of old-new status and (b) items that were not discriminated in recognition nonetheless showed priming. However, the authors show that these data, together with the group-level results, are compatible with a formal model in which priming and recognition are based on a single common memory variable. 相似文献
853.
The locations of visual objects and events in the world are represented in a number of different coordinate frameworks. For example, a visual transient is known to attract (exogenous) attention and facilitate performance within an egocentric framework. However, when attention is allocated voluntarily to a particular visual feature (ie endogenous attention), the location of that feature appears to be variously encoded either within an allocentric framework or in a spatially invariant manner. In three experiments we investigated the importance of location for the allocation of endogenous attention and whether egocentric and/or allocentric spatial frameworks are involved. Primes and targets were presented in four conditions designed to vary systematically their spatial relationships in egocentric and allocentric coordinates. A reliable effect of egocentric priming was found in all three experiments, which suggests that endogenous shifts of attention towards targets defined by a particular feature operate in an egocentric representation of visual space. In addition, allocentric priming was also found for targets primed by their colour or shape. This suggests that attending to targets primed by nonspatial attributes results in facilitation that is localised in more than one coordinate frame of spatial reference. 相似文献
854.
Rustad RA Small JE Jobes DA Safer MA Peterson RJ 《Suicide & life-threatening behavior》2003,33(2):120-131
In Experiment 1, 133 college student volunteers watched a rock music video with or without suicidal content and then completed written measures assessing mood, priming of suicide-related thoughts, perceptions of personal risk, sensitivity to suicidality in others, and attitudes/beliefs about suicide. In Experiment 2, 104 college student volunteers listened to rock music with either suicidal or neutral content and then completed measures similar to Experiment 1, with the addition of a hopelessness measure. In both experiments, participants exposed to suicidal content wrote more scenarios with suicide-related themes in a projective storytelling task than those exposed to nonsuicidal content. However, there were virtually no group differences on explicit measures of affect, attitudes, and perceptions. Music and videos with suicide content appeared to prime implicit cognitions related to suicide but did not affect variables associated with increased suicide risk. 相似文献
855.
856.
Despite the prominence of the disability civil rights model--with its values of inclusion and empowerment--the majority of social and policy research conducted to date has not sufficiently included the perspective of persons with disabilities in the research process and as uniquely qualified researchers themselves. This article describes a new project, "Technology for Independence: A Community-Based Resource Center" (CBRC). Over a five-year period, the CBRC will attempt to enhance community and consumer-directed disability organizations to design, implement, and disseminate research that promotes access to and use of assistive technology (AT). The CBRC will use strategies such as leadership training, participatory action research, technical assistance, web-assisted training, and annual symposia. A primary goal of the CBRC is to increase the capacity of community organizations to conduct research on AT that is scientifically rigorous and relevant to disability services, policy, and law. 相似文献
857.
Previous research has suggested that, relative to younger adults, older adults devote a greater proportion of their discourse processing to the situation model level. The current experiment assessed whether this is due, in part, to a preserved ability to focus on functionally appropriate information. The focus here was on spatial relations. Both reading time and recognition data showed superior performance for functional over nonfunctional information, and this functional effect was similar in younger and older adults. This is consistent with the idea that older adults' ability to process information at the situation model level is relatively well preserved. 相似文献
858.
Environmental support promotes expertise-based mitigation of age differences on pilot communication tasks 总被引:3,自引:0,他引:3
Morrow DG Ridolfo HE Menard WE Sanborn A Stine-Morrow EA Magnor C Herman L Teller T Bryant D 《Psychology and aging》2003,18(2):268-284
The authors investigated whether expertise is more likely to mitigate age declines when experts rely on environmental support in a pilot/Air Traffic Control (ATC) communication task. Pilots and nonpilots listened to ATC messages that described a route through an airspace, while they referred to a chart of the airspace. They read back (repeated) each message and then answered a probe question about the route. In a preliminary study, participants could take notes while listening to the messages and performing the read-back and probe tasks. In Experiment 1, opportunity to take notes was manipulated. Note taking determined when expertise mitigated age differences on the read-back task. With note taking, read-back accuracy declined with age for nonpilots but not for pilots. Without note taking, similar age-related declines occurred for pilots and nonpilots. Benefits of expertise, younger age, and note taking occurred for probe accuracy, but mitigation did not occur. The findings suggest that older adults take advantage of a domain-relevant form of environmental support (note taking) to maintain performance on some complex tasks despite typical age-related declines in cognitive ability. 相似文献
859.
The authors used 6-year longitudinal data from the Victoria Longitudinal Study (VLS) to investigate individual differences in amount of episodic memory change. Latent change models revealed reliable individual differences in cognitive change. Changes in episodic memory were significantly correlated with changes in other cognitive variables, including speed and working memory. A structural equation model for the latent change scores showed that changes in speed and working memory predicted changes in episodic memory, as expected by processing resource theory. However, these effects were best modeled as being mediated by changes in induction and fact retrieval. Dissociations were detected between cross-sectional ability correlations and longitudinal changes. Shuffling the tasks used to define the Working Memory latent variable altered patterns of change correlations. 相似文献
860.
David K. Carson Kent W. Becker Kevin E. Vance Nancy L. Forth 《Contemporary Family Therapy》2003,25(1):89-109
The purpose of this study, using an online methodology, was to investigate therapists' perceptions of the role of creativity in couples' and family therapy. Along with completing a quantitative measure assessing creativity in their work, participants responded to four open-ended questions which addressed the meaning of creativity, characteristics of a creative family therapist, some creative interventions they have used with couples and families, and barriers to their own creativity as a family therapist. A total of 142 marriage and family therapists in 36 states in the United States participated. The findings shed light on the unique importance of creativity in couples and family treatment. 相似文献