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941.
Functional magnetic reasonance imaging (fMRI) plays an important role in pre-surgical planning for patients with resectable brain lesions such as tumors. With appropriately designed tasks, the results of fMRI studies can guide resection, thereby preserving vital brain tissue. The mass univariate approach to fMRI data analysis consists of performing a statistical test in each voxel, which is used to classify voxels as either active or inactive—that is, related, or not, to the task of interest. In cognitive neuroscience, the focus is on controlling the rate of false positives while accounting for the severe multiple testing problem of searching the brain for activations. However, stringent control of false positives is accompanied by a risk of false negatives, which can be detrimental, particularly in clinical settings where false negatives may lead to surgical resection of vital brain tissue. Consequently, for clinical applications, we argue for a testing procedure with a stronger focus on preventing false negatives. We present a thresholding procedure that incorporates information on false positives and false negatives. We combine two measures of significance for each voxel: a classical p-value, which reflects evidence against the null hypothesis of no activation, and an alternative p-value, which reflects evidence against activation of a prespecified size. This results in a layered statistical map for the brain. One layer marks voxels exhibiting strong evidence against the traditional null hypothesis, while a second layer marks voxels where activation cannot be confidently excluded. The third layer marks voxels where the presence of activation can be rejected.  相似文献   
942.
The dual-representation model of posttraumatic stress disorder (PTSD; Brewin, Gregory, Lipton, & Burgess, Psychological Review, 117, 210-232 2010) argues that intrusions occur when people fail to construct context-based representations during adverse experiences. The present study tested a specific prediction flowing from this model. In particular, we investigated whether the efficiency of temporal-lobe-based spatial configuration learning would account for individual differences in intrusive experiences and physiological reactivity in the laboratory. Participants (N = 82) completed the contextual cuing paradigm, which assesses spatial configuration learning that is believed to depend on associative encoding in the parahippocampus. They were then shown a trauma film. Afterward, startle responses were quantified during presentation of trauma reminder pictures versus unrelated neutral and emotional pictures. PTSD symptoms were recorded in the week following participation. Better configuration learning performance was associated with fewer perceptual intrusions, r = ?.33, p < .01, but was unrelated to physiological responses to trauma reminder images (ps > .46) and had no direct effect on intrusion-related distress and overall PTSD symptoms, rs > ?.12, ps > .29. However, configuration learning performance tended to be associated with reduced physiological responses to unrelated negative images, r = ?.20, p = .07. Thus, while spatial configuration learning appears to be unrelated to affective responding to trauma reminders, our overall findings support the idea that the context-based memory system helps to reduce intrusions.  相似文献   
943.
A central issue in education is how to support the spatial thinking involved in learning science, technology, engineering, and mathematics (STEM). We investigated whether and how the cognitive process of analogical comparison supports learning of a basic spatial concept in geoscience, fault. Because of the high variability in the appearance of faults, it may be difficult for students to learn the category-relevant spatial structure. There is abundant evidence that comparing analogous examples can help students gain insight into important category-defining features (Gentner in Cogn Sci 34(5):752–775, 2010). Further, comparing high-similarity pairs can be especially effective at revealing key differences (Sagi et al. 2012). Across three experiments, we tested whether comparison of visually similar contrasting examples would help students learn the fault concept. Our main findings were that participants performed better at identifying faults when they (1) compared contrasting (fault/no fault) cases versus viewing each case separately (Experiment 1), (2) compared similar as opposed to dissimilar contrasting cases early in learning (Experiment 2), and (3) viewed a contrasting pair of schematic block diagrams as opposed to a single block diagram of a fault as part of an instructional text (Experiment 3). These results suggest that comparison of visually similar contrasting cases helped distinguish category-relevant from category-irrelevant features for participants. When such comparisons occurred early in learning, participants were more likely to form an accurate conceptual representation. Thus, analogical comparison of images may provide one powerful way to enhance spatial learning in geoscience and other STEM disciplines.  相似文献   
944.
Fifty-three national level cyclists completed competitive rides under both laboratory and field conditions to investigate the relationship between pre-competition anxiety and performance. A total of 39 males and 14 females participated in the study, ranging in age from 19 to 26. The objectives of the study were to, (a) measure the relationship between state anxiety and performance, (b) investigate differences in the anxiety-performance relationship under laboratory versus field conditions, and (c) examine the effect of trait anxiety on the state anxiety-performance relationship. State anxiety was measured using the Competitive State Anxiety Inventory-2 (CSAI-2; Martens, Vealey, & Burton, 1990), and trait anxiety with the State-Trait Anxiety Inventory (STAI; Spielberger, Gorsuch, & Lushene, 1970). Results indicated that anxiety was strongly correlated with performance on the field test, but that the anxiety-performance relationship was weaker under laboratory conditions. Results also showed that trait anxiety interacted with the relationship, as low and high trait-anxious subjects had differential response patterns to pre-competition anxiety. The findings are discussed in terms of their relevance for both practitioners and researchers.  相似文献   
945.
Our target article proposed an alternative perspective for studying consumer judgment and decision making, focusing on the types and weights of comparisons consumers select. In this response we consider the major points made by each of the commentators and examine their implications for future work addressing our comparison-focused approach.  相似文献   
946.
Measures of test emotions other than test anxiety are lacking. In a series of six studies, we developed a multi-scale questionnaire assessing test-related joy, hope, pride, relief, anger, anxiety, shame, and hopelessness (Test Emotions Questionnaire, TEQ). Consisting of subscales measuring affective, cognitive, physiological, and motivational emotion components, the scales can be used to identify both trait and state test emotions, and are available in German- and English-language versions. Using a rational-empirical strategy of test construction, we first developed theoretical models of the component structures, antecedents, and effects of different test emotions. We then conducted two exploratory, qualitative studies on the occurrence and structures of these emotions. Finally, based on theory and our exploratory data, we constructed, analyzed, and revised the scales of the TEQ in four quantitative studies. Findings of correlational and confirmatory factor analysis indicate that the scales are reliable, structurally valid in terms of representing different test emotions and components within emotions, and externally valid in terms of correlating significantly with personality, learning, academic achievement, and perceived health problems. Many of these correlations proved to be stronger for test emotions other than anxiety, implying that test anxiety is neither the only relevant test emotion, nor necessarily the most important one.  相似文献   
947.
Research on the impact of letter transpositions that arise across morpheme boundaries has yielded conflicting results. These results have led to the suggestion that a cross-linguistic difference may exist in the recognition of Spanish and English words. In two masked-priming experiments run on separate groups of Spanish and English speakers, we tested this hypothesis by comparing the impacts of primes with letter transpositions that arose within morphemes or across morpheme boundaries on the recognition of identical or near-identical Spanish–English cognate targets. The results showed transposed-letter benefits in both Spanish and English that were not modulated by the position of the transposed letter in the prime stimulus. Our findings therefore add to the growing body of literature suggesting that the transposed-letter benefit is not affected by the position of the transposed letters relative to the morpheme boundary, and they dispel previous suggestions that there might be a genuine difference in orthographic coding across the Spanish and English writing systems.  相似文献   
948.
Working memory is a construct of primary relevance to many areas of psychology. Two types of tasks have been used to measure working memory, primarily in different research areas: Complex span tasks are commonly used in behavioral studies in the cognitive and individual-differences literature, whereas n-back tasks have been used more frequently in cognitive neuroscience studies investigating the neural underpinnings of working memory. Despite both categories of tasks being labeled as “working memory” measures, previous empirical studies have provided mixed evidence regarding the shared amount of overlapping processes between complex span and n-back tasks. The present meta-analysis showed that the complex span and n-back tasks are weakly correlated, although significant heterogeneity across studies was observed. A follow-up analysis of unpublished data indicated that the sample composition affects the relationship between the complex span and n-back tasks, following the law of diminishing returns. Finally, a separate meta-analysis indicated that the simple span and n-back tasks are correlated to the same extent as are the complex span and n-back tasks. The present findings indicate that the complex span and n-back tasks cannot be used interchangeably as working memory measures in research applications.  相似文献   
949.
This study demonstrates how gathering data from a different context can significantly change how an object of study may be viewed. Data from a qualitative diary study of psychotherapeutic practice were used to construct a cross-contextual view of psychotherapy. Data about clients’ everyday lives as well as psychotherapy sessions were analyzed. Examples of how extra-therapeutic factors are significant to client change are presented. Six types of extra-therapeutic information sources that clients use to develop their personal stances while in therapy were identified. The case of one client's abundant use of extra-therapeutic sources of information offers a different construction of how psychotherapy works, emphasizing client activities outside sessions. The implications of the study for psychotherapy research are addressed.  相似文献   
950.
The co-occurrence of posttraumatic stress disorder (PTSD) and traumatic brain injury (TBI) is common among military personnel returning from deployments in Iraq and Afghanistan. Despite the prevalence, scant evidence exists to inform clinicians as how to best treat these individuals, particularly for individuals with PTSD and a history of severe TBI. This case study presents the course of treatment in a VA residential PTSD/TBI program for an Operation Iraqi Freedom Veteran with PTSD, a history of severe TBI, and other psychiatric comorbidities. Cognitive Processing Therapy–Cognitive (CPT-C) was utilized as the primary PTSD treatment in conjunction with ancillary treatment. Data obtained during and following treatment suggest that CPT-C, without modifications to the protocol, offered within a residential treatment program may be an effective treatment for veterans with PTSD and a history of severe TBI.  相似文献   
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