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821.
To date, research on storm phobia has been limited by a lack of validated self-report measures for evaluating the severity of anxiety, phobic avoidance, and distress associated with storms and severe weather. The current research presents the development and validation of the Storm Fear Questionnaire (SFQ), a 15-item self-report questionnaire that assesses the cognitive, affective, and behavioral aspects thought to be associated with Storm Phobia in adults. Three studies were conducted to assess 1) the factor structure, internal consistency, and convergent and discriminant validity of the SFQ, 2) the test-retest reliability of the SFQ, 3) the extent that scores on the SFQ were associated with subjective anxiety ratings during a Behavioral Approach Test (BAT) involving exposure to a virtual thunderstorm, and the extent to which SFQ scores distinguished community participants with versus without a fear of storms. Exploratory factor analyses supported a one-factor model with good internal consistency (Cronbach’s α?=?.95), good convergent and discriminant validity with self-report measures of anxiety, worry, depression, and other specific phobias, and acceptable test-retest reliability. Moreover, there was a significant positive association between SFQ scores and anxiety ratings following the BAT involving exposure to a virtual thunderstorm and participants with a high fear of storms reported significantly higher SFQ scores than those with a low fear of storms. In sum, the SFQ has good psychometric properties and appears to be a valuable tool for assessing the severity of fear associated with storms and severe weather. Research evaluating the diagnostic and clinical utility of the SFQ is still needed.  相似文献   
822.
How internal categories influence how we perceive the world is a fundamental question in cognitive sciences. Yet, the relation between perceptual awareness and perceptual categorization has remained largely uncovered so far. Here, we addressed this question by focusing on face perception during subliminal and conscious perception. We used morphed continua between two face identities and we assessed, through a masked priming paradigm, the perceptual processing of these morphed faces under subliminal and supraliminal conditions. We found that priming from subliminal faces followed linearly the information present in the primes, while priming from visible faces revealed a non-linear profile, indicating a categorical processing of face identities. Our results thus point to a special relation between perceptual awareness and categorical processing of faces, and support the dissociation between two modes of information processing: a subliminal mode involving analog treatment of stimuli information, and a supraliminal mode relying on discrete representation.  相似文献   
823.
The goal of the current project was to determine (a) the cognitive abilities assessed by the Mini Mental State Examination (MMSE; M. F. Folstein, S. E. Folstein, & P. R. McHugh, 1975), (b) whether the same abilities are associated with MMSE performance among people of different ages, and (c) whether the same abilities are involved in changes within the same people over time. The authors therefore examined whether the initial levels of 5 cognitive ability constructs (vocabulary, reasoning, memory, space, and speed) predicted initial levels of MMSE performance and whether the initial levels or the changes in these 5 cognitive abilities predicted change in the MMSE performance. The major findings were that 3 cognitive constructs (vocabulary, reasoning, and memory) contribute to performance in the MMSE but that their respective contributions to the MMSE vary as a function of age and time. In particular, individual differences and change in the MMSE are primarily related to individual differences in reasoning among adults younger than about 70 years, whereas both initial level of MMSE performance and longitudinal change in MMSE performance primarily related to initial level and change in memory ability among adults older than 70 years. The results therefore imply that both the level of performance on the MMSE at a single point in time and the change in MMSE over time may represent somewhat different cognitive abilities at different ages.  相似文献   
824.
Twenty treated and 18 untreated spider phobics were exposed to a series of 72 slides. Three different categories of slides were used: phobia-relevant slides (spiders), alternative fear-relevant slides (weapons), and neutral slides (flowers). Slides were randomly paired with either a shock, a tone, or nothing at all. Despite the absence of a systematic correlation between slides and outcomes, untreated phobics strongly overestimated the covariation between spider slides and shock. Treated phobics did not show a covariation bias, suggesting that such bias can be modulated by behavioral treatment. In addition, untreated subjects were more confident about their contingency estimates than were treated subjects. The present results fit with earlier studies.  相似文献   
825.
The use of neurological tests in various states of undernutrition has confirmed the presence of delays in reflex ontogeny. Glucocorticoid administration in conditions of normal nutrition produces diminished growth and alterations in brain development similar to those observed in malnutrition, but there is not enough evidence about its effect on reflex development. In addition, some facts lead us to think that the use of permissive doses of these hormones during gestation could alleviate some of the effects of protein malnutrition on the development of pups. In the present study the ages at which certain reflexes appeared in the offspring of Wistar rats (Rattus norvegicus) fed a 20% (N) or 10% (M) protein diet from a week before conception to the end of lactation were observed. Each dietary group was subdivided into two: mothers receiving a daily injection during gestation either of a 0.9% NaCl (S) solution or of a 0.5 mg/100 g weight hydrocortisone acetate (C) solution. Results showed that the NS group of pups generally presented earlier ages of appearance of the variables under study than the remaining groups. Pups of the NC group presented delays in the age of appearance of reflexes. Finally, protein malnutrition delayed the appearance of reflexes and this effect seemed to be attenuated by treatment with hydrocortisone. Thus, hydrocortisone administration in protein malnutrition conditions seems to be beneficial although the results are harmful when administered under normal nutritional conditions.  相似文献   
826.
A variety of evidence shows that the amplitude of respiratory sinus arrhythmia (RSA)—the peak-to-peak variations in heart rate caused by respiration—is a valid and reliable index of para-sympathetic cardiac control. An on-line program to calculate RSA amplitude on a breath-by-breath basis is described. The validity of the RSA amplitude values obtained through the computer pro-gram were tested in two studies. From the first one, the correlations between RSA amplitude and a set of cardiorespiratory variables, under both rest and auditory stimulation conditions, are reported. In the second study, the effect of atropine administration on the RSA amplitude, under both rest and mental load conditions, was examined. The results of both studies are con-gruent with predictions and suggest the usefulness of the software.  相似文献   
827.
In three studies we addressed the impact of perceived risk and negative affect on risky choice. In Study 1, we tested a model that included both perceived risk and negative affect as predictors of risky choice. Study 2 and Study 3 replicated these findings and examined the impact of affective versus cognitive processing modes. In all the three studies, both perceived risk and negative affect were shown to be significant predictors of risky choice. Furthermore, Study 2 and Study 3 showed that an affective processing mode strengthened the relation between negative affect and risky choice and that a cognitive processing mode strengthened the relation between perceived risk and risky choice. Together, these findings show support for the idea of a dual‐process model of risky choice. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   
828.
The main objective of the present study was to examine the role of motivation and action orientation in forming spontaneous (i.e., without specific instruction or manipulation) implementation intentions for a healthy diet goal. We hypothesized that (1) the adoption of a diet goal would be determined by (either intrinsic or extrinsic) motivation only whereas, (2) forming implementation intentions would be determined by intrinsic motivation and (either low or high) action orientation. These hypotheses were addressed in a sample of 142 normal weight subjects who were concerned about their dietary habits. Primary outcomes were goal intentions and implementation intentions. Our hypothesis regarding the prediction of goal intentions was confirmed whereas results relating to the prediction of implementation intentions demonstrated that intrinsic motivation and low (but not high) action orientation proved significant predictors of intentions to implement a healthy diet goal. These findings suggest that self‐regulatory skills as assessed by the concept of action orientation may relate to short‐term strategies of initiating behavior change only. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   
829.
830.
Research has shown that the visual system’s sensitivity to variations in luminance (visual contrast) within a particular area of the retina is affected in a bottom-up fashion by the ambient contrast levels in nearby regions. Specifically, changes in the ambient contrast in areas surrounding the target area alter the sensitivity to visual contrast within the target area. More recent research has shown that paying attention to the target or target area modulates contrast sensitivity, suggesting a top-down influence over contrast sensitivity that is mediated by attention. Here we report another form of top-down influence over contrast sensitivity that is unlikely to be mediated by attention. In particular, we show that knowledge and/or expectations about the levels of visual contrast that may appear in upcoming targets also affect how sensitive the observer is to the contrast in the target. This sort of knowledge-driven, top-down contrast sensitivity control could be used to preset the visual system’s contrast sensitivity to maximize discriminability and to protect contrast-sensitive processes from a contrast overload. Overall, our results suggest that existing models of contrast sensitivity might benefit from the inclusion of top-down control mechanisms.  相似文献   
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