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991.
Although research on the reasons for engaging in nonsuicidal self-injury (NSSI) has increased dramatically in the last few years, there are still many aspects of this pernicious behavior that are not well understood. The purpose of this study was to address these gaps in the literature, with a particular focus on investigating whether NSSI (a) regulates affective valence in addition to affective arousal and (b) serves a cognitive regulation function in addition to an affect regulation function. To elucidate these issues, the present study utilized a sample of 112 participants (33 controls, 39 no pain controls, 16 NSSI individuals, and 24 controls matching the affect dysregulation levels of the NSSI group), employed psychophysiological measures of affective valence (startle-alone reactivity) and quality of information processing (prepulse inhibition), and used experimental methods involving an NSSI-proxy to model the NSSI process. Results largely were consistent with predictions, supporting the hypotheses that NSSI serves to regulate cognitive processing and affective valence. On this latter point, however, the control groups also showed a decrease in negative affective valence after the NSSI-proxy. This unexpected finding is consistent with the hypothesis that opponent processes may contribute to the development of self-injurious behaviors (Joiner, 2005). Overall, the present study represents an important extension of previous laboratory NSSI studies and provides a fertile foundation for future studies aimed at understanding why people engage in NSSI.  相似文献   
992.
We evaluated an intervention that combined task analysis and differential reinforcement for teaching tackling skills to 2 high school football athletes. As a result of intervention, both players tackled more proficiently in practice drills and maintained proficient tackling during games.  相似文献   
993.
Differences in people’s reactions to the same events described with full vs. sketchy information are examined. It is hypothesized that differences in counterfactual thought reactions to varying levels of event detail shape confidence in, and willingness to gamble on similar, future events. In three experiments, participants were presented with different types and levels of event detail about their performances on a trivia test, on several games of blackjack, or on gambling on a professional horse race. Upward counterfactual thoughts were observed more frequently in response to losing events containing high levels of detail and specificity. Importantly, counterfactual thought frequency also mediated the relationships between event detail and the level of confidence in and willingness to gamble on similar, future events. Evidence also indicates that this relationship is based on the hindsight bias that results from counterfactual thinking. Results are discussed in terms of cognitive processes and decision making research.  相似文献   
994.
We present a simple but effective method based on Luce’s choice axiom [Luce, R.D. (1959). Individual choice behavior: A theoretical analysis. New York: John Wiley & Sons] for consistent estimation of the pairwise confusabilities of items in a multiple-choice recognition task with arbitrarily chosen choice-sets. The method combines the exact (non-asymptotic) Bayesian way of assessing uncertainty with the unbiasedness emphasized in the classical frequentist approach.We apply the method to data collected using an adaptive computer game designed for prevention of reading disability. A player’s estimated confusability of phonemes (or more accurately, phoneme-grapheme connections) and larger units of language is visualized in an easily understood way with color cues and explicit indication of the accuracy of the estimates. Visualization of learning-related changes in the player’s performance is considered.The empirical validity of the choice axiom is evaluated using the game data itself. The axiom appears to hold reasonably well although a small systematic violation is observable for the smallest choice-set sizes.  相似文献   
995.
Self-Efficacy and the Prediction of Domain-Specific Cognitive Abilities   总被引:1,自引:0,他引:1  
ABSTRACT We evaluated predictors of performance in 4 specific cognitive ability domains: verbal, numerical, spatial, and mechanical. The predictors were individual differences in self-efficacy beliefs, self-enhancement tendencies, and cross-domain abilities. Our university students' beliefs about their verbal, numerical, and spatial capabilities correlated well with their actual performance on standardized tests (verbal r =.33, numerical r =.27, spatial r =.36). In contrast, the students' self-efficacy for mechanical tasks did relatively poorly in predicting mechanical test performance ( r =.10). Most interesting were two other findings: (a) The best predictor of domain performance was level of cross-domain performance by far, even for mechanical tasks, and (b) self-enhancement tendencies added to cross-domain abilities and self-efficacy beliefs in the prediction of performance. The results are discussed in terms of possible mechanisms explaining how one's score on a maximal performance task can be affected by self-efficacy beliefs and self-enhancement tendencies.  相似文献   
996.
997.
This research introduces the concept of implicit theories of attitude stability. Across three studies, individuals are shown to vary both naturally and situationally in their lay theories about the stability of attitudes. Furthermore, these general theories are shown to impact people's certainty in their specific attitudes by shaping their perceptions of the stability of the attitude under consideration. By affecting attitude certainty, implicit theories of attitude stability also influence the extent to which people rely on their attitude when committing to future attitude-relevant behavior. Moreover, following exposure to a persuasive attack, implicit theories are shown to interact with situational perceptions of attitude stability to determine attitude certainty. Collectively, these findings suggest that implicit theories of attitude stability have an important influence on people's attitude certainty, subsequent behavioral intentions, and resistance to persuasive messages. Future directions concerning the potential impact of these theories for other attitudinal phenomena are discussed.  相似文献   
998.
Adaptive learning games should provide opportunities for the student to learn as well as motivate playing until goals have been reached. In this paper, we give a mathematically rigorous treatment of the problem in the framework of Bayesian decision theory. To quantify the opportunities for learning, we assume that the learning tasks that yield the most information about the current skills of the student, while being desirable for measurement in their own right, would also be among those that are efficient for learning. Indeed, optimization of the expected information gain appears to naturally avoid tasks that are exceedingly demanding or exceedingly easy as their results are predictable and thus uninformative. Still, tasks that are efficient for learning may be experienced as too challenging, and the resulting failures can lower motivation. Therefore, in addition to quantifying the expected informational benefit for learning of any prospective task to be presented next, we also model the expected motivational cost of its presentation, measured simply as the estimated probability of failure in our example model. We propose a “learner-friendly” adaptation algorithm that chooses the learning tasks by optimizing the expected benefit divided by the expected cost. We apply this algorithm to a Rasch-like student model implemented within a real-world application and present initial results of a pilot experiment.  相似文献   
999.
Individual vocal recognition behaviors in songbirds provide an excellent framework for the investigation of comparative psychological and neurobiological mechanisms that support the perception and cognition of complex acoustic communication signals. To this end, the complex songs of European starlings have been studied extensively. Yet, several basic parameters of starling individual vocal recognition have not been assessed. Here we investigate the temporal extent of song information acquired by starlings during vocal recognition learning. We trained two groups of starlings using standard operant conditioning techniques to recognize several songs from two conspecific male singers. In the first experiment we tested their ability to maintain accurate recognition when presented with (1) random sequences of 1–12 motifs (stereotyped song components) drawn from the training songs, and (2) 0.1–12-s excerpts of continuous song drawn from the training songs. We found that song recognition improved monotonically as more vocal material is provided. In the second experiment, we systematically substituted continuous, varying length regions of white noise for portions of the training songs and again examined recognition accuracy. Recognition remained above chance levels for all noise substitutions tested (up to 91% of the training stimulus) although all but the smallest substitutions led to some decrement in song recognition. Overall, above chance recognition could be obtained with surprisingly few motifs, short excerpts of song, and in the absence of large portions of the training songs. These results suggest that starlings acquire a representation of song during individual vocal recognition learning that is robust to perturbations and distributed broadly over large portions of these complex acoustic sequences.  相似文献   
1000.
Restricted stimulus control refers to discrimination learning with atypical limitations in the range of controlling stimuli or stimulus features. In the study reported here, 4 normally capable individuals and 10 individuals with intellectual disabilities (ID) performed two-sample delayed matching to sample. Sample-stimulus observing was recorded with an eye-tracking apparatus. High accuracy scores indicated stimulus control by both sample stimuli for the 4 nondisabled participants and 4 participants with ID, and eye tracking data showed reliable observing of all stimuli. Intermediate accuracy scores indicated restricted stimulus control for the remaining 6 participants. Their eye-tracking data showed that errors were related to failures to observe sample stimuli and relatively brief observing durations. Five of these participants were then given interventions designed to improve observing behavior. For 4 participants, the interventions resulted initially in elimination of observing failures, increased observing durations, and increased accuracy. For 2 of these participants, contingencies sufficient to maintain adequate observing were not always sufficient to maintain high accuracy; subsequent procedure modifications restored it, however. For the 5th participant, initial improvements in observing were not accompanied by improved accuracy, an apparent instance of observing without attending; accuracy improved only after an additional intervention that imposed contingencies on observing behavior. Thus, interventions that control observing behavior seem necessary but may not always be sufficient for the remediation of restricted stimulus control.  相似文献   
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