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971.
Response time (RT) generally slows with aging, but the contribution of structural brain changes to this slowing is unknown. We used voxel-based morphometry (VBM) to determine gray matter (GM) and white matter (WM) brain volumes in 9 middle-aged adults (38–58 years old) and 9 seniors (66–82 years old). We correlated brain volumes with RT assessed in both a simple visual stimulus-response task and a visual continuous recognition memory task. No GM correlations with simple RT were significant; there was one WM correlation in the right fusiform gyrus. In the memory task, faster RT was correlated (p<.05, corrected) with less GM in the globus pallidus, the parahippocampus, and the thalamus for both groups. Several Brodmann areas (BA) differed between the groups such that in each area, less GM was correlated with slower RTs in the middle-aged group but with faster RTs in the senior group (BAs 19, 37, 46, 9, 8, 6, 13, 10, 41, and 7). The results suggest that individual differences in specific brain structure volumes should be considered as potential moderating factors in cognitive brain imaging studies.  相似文献   
972.
We describe WebDiP (Web Decision Processes)&#x2014;an open-source, online tool&#x2014;which enables a researcher to track participants while they search for information in a database, available through the Internet. After various instructions on setup and configuration are given, a detailed view of WebDiP explains the system’s technical features. Furthermore, other open-source tools are mentioned that helped in programming WebDiP, running it, or analyzing data gathered with it. We present new approaches of how open-source thinking can be incorporated into a research process and discuss future perspectives of WebDiP.  相似文献   
973.
Expert review sessions are often conducted to determine the content validity of scale items. The accurate quantification of content validity is usually limited by a relatively small number of experts as well as by a small number of rating categories. These factors, combined with the bounded and discrete nature of rating scale categories, hinder use of traditional methods for computing standard errors and confidence intervals. Using an application of the score method, researchers can construct an asymmetric interval that is better suited for these situations. SAS code is provided to automate the computations, and a discussion of two methods for using the obtained results for content validation decisionmaking follows.  相似文献   
974.
Previous research and theory have conceptualized impulsivity as a multifaceted construct that requires multiple modes of measurement for accurate assessment. This article describes a software package that includes four paradigms for measuring multiple and unique aspects of impulsivity. Specifically, four tasks are described: (1) the two choice impulsivity paradigm, (2) the single key impulsivity paradigm, (3) the GoStop impulsivity paradigm, and (4) the time paradigm. These tasks measure processes related to the capacity to tolerate delay for reward, to inhibit an already initiated response, and to estimate the passage of time. These processes have been found to be important to the understanding of impulsive behaviors. The programs are flexible and allow the experimenter to manipulate a number of parameters related to delay-reward contingencies, timing, performance feedback/payment, and data output variables. Manipulation of these parameters makes the paradigms scalable to a wide range of ability levels and appropriate for samples ranging from children to adults. The four paradigms in this software package are available at no cost and can be obtained by contacting the corresponding author.  相似文献   
975.
Synchronizing the display of a stimulus with physiological recording or subjects’ behavioral responses is crucial for acquiring valid measures of performance. This article describes a technique for integrating the presentation of stimuli, behavior reports, and physiological data employing Macromedia Director and a standard biometric program using an example from the field of developmental psychopathology. Our experience has been that the use of this technique is effective in creating complex protocols for research. Although the temporal accuracy available from this particular method is adequate for some experiments, it is not suited for investigations requiring single millisecond accuracy. Considerations and suggestions for utilizing this and similar techniques for integrating data collection and stimuli presentation are discussed.  相似文献   
976.
We provide objective data concerning the age of acquisition (AoA) of words from 202 Italian children 34–69 months of age. We investigated picture naming with 80 concrete words belonging to eight semantic categories that are included in a widely used battery for the study of naming and semantic memory. For each word, we calculated three different indices: two directly expressing the age at which a picture was given the correct name by at least 75% of the subjects, and one expressing the overall percentage of our children who were correct in the task. (For the latter index, we provide separate values for boys and girls.) The correlation between objective indices of AoA and adult estimates culled from the literature was not very high. Moreover, objective indices showed low correlations with frequency and familiarity, in contrast to adult ratings. We conclude that adult estimates of AoA present validity problems and should be used with caution. The full set of stimuli is available at www.psychonomic.org/archive.  相似文献   
977.
This article presents a method for using Microsoft (MS) Excel for confirmatory factor analysis (CFA). CFA is often seen as an impenetrable technique, and thus, when it is taught, there is frequently little explanation of the mechanisms or underlying calculations. The aim of this article is to demonstrate that this is not the case; it is relatively straightforward to produce a spreadsheet in MS Excel that can carry out simple CFA. It is possible, with few or no programming skills, to effectively program a CFA analysis and, thus, to gain insight into the workings of the procedure.  相似文献   
978.
A review of the literature and ethnographic data from Australia, Canada, New Zealand, the United States, and the United Kingdom on the research ethics review process suggest that moral panics can become triggers for punctuated equilibrium in the review process at both the macro and microlevel, albeit with significantly different levels of magnitude and impact. These data suggest that neither the development of the ethics review process nor the process itself proceeds gradually, but both are characterized by periodic major shifts evoked by particular events or situations that result in varying levels of moral panic. One way to deal with this moral panic is to increase the regulation of research and the depth or intensity of the scrutiny of applications under ethics review. Moral panics at the macrolevel influence those at the microlevel and, if the moral panic evoked at the local or microlevel is not satisfactorily resolved, it will evoke action at a higher level. Understanding the evolution of research ethics review processes from this perspective might help make actions by ethics committees and policy makers more understandable and help explain why attention to research ethics are heightened at particular points in time. It may also provide a basis for developing recommendations for adaptations to the ethics review process and policy at both the local and macrolevel.  相似文献   
979.
A proposal for the biological grounding of intrinsic teleology and sense-making through the theory of autopoiesis is critically evaluated. Autopoiesis provides a systemic language for speaking about intrinsic teleology but its original formulation needs to be elaborated further in order to explain sense-making. This is done by introducing adaptivity, a many-layered property that allows organisms to regulate themselves with respect to their conditions of viability. Adaptivity leads to more articulated concepts of behaviour, agency, sense-construction, health, and temporality than those given so far by autopoiesis and enaction. These and other implications for understanding the organismic generation of values are explored.  相似文献   
980.
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