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131.
The classic goal-gradient hypothesis posits that motivation to reach a goal increases monotonically with proximity to the desired end state. However, we argue that this is not always the case. In this article, we show that motivation to engage in goal-consistent behavior can be higher when people are either far from or close to the end state and lower when they are about halfway to the end state. We propose a psychophysical explanation for this tendency to get "stuck in the middle." Building on the assumption that motivation is influenced by the perceived marginal value of progress toward the goal, we show that the shape of the goal gradient varies depending on whether an individual monitors progress in terms of distance from the initial state or from the desired end state. Our psychophysical model of goal pursuit predicts a previously undiscovered nonmonotonic gradient, as well as two monotonic gradients. 相似文献
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133.
Rinaldo P Zafari S Tortorelli S Matern D 《Mental retardation and developmental disabilities research reviews》2006,12(4):255-261
The expansion of newborn screening programs to include multiplex testing by tandem mass spectrometry requires understanding and close monitoring of performance metrics. This is not done consistently because of lack of defined targets, and interlaboratory comparison is almost nonexistent. Between July 2004 and April 2006 (N=176,185 cases), the overall performance metrics of the Minnesota program, limited to MS/MS testing, were as follows: detection rate 1:1,816, positive predictive value 37% (54% in 2006 till date), and false positive rate 0.09%. The repeat rate and the proportion of cases with abnormal findings actually been reported are new metrics proposed here as an objective mean to express the overall noise in a program, where noise is defined as the total number of abnormal results obtained using a given set of cut-off values. On the basis of our experience, we propose the following targets as evidence of adequate analytical and postanalytical performance: detection rate 1:3,000 or higher, positive predictive value>20%, and false positive rate<0.3%. 相似文献
134.
135.
Exposure to panic symptoms (interoceptive exposure) is often included as part of treatment for panic disorder (PD), although little is known about the relative effects of particular symptom induction exercises. This study describes responses of individuals with PD and nonclinical controls to 13 standard symptom induction exercises and 3 control exercises. Generally, individuals with PD responded more strongly to symptom induction exercises than did controls. The exercises producing the most fear included spinning, hyperventilation, breathing through a straw, and using a tongue depressor. This study also reports findings regarding specific symptoms triggered by each exercise, the percentage of participants reporting fear during each exercise, and predictors of fear. 相似文献
136.
This study examined the impact of state anxiety, trait anxiety, and anxiety sensitivity on physiological and self-report measures of sexual arousal and sexual function in a non-clinical sample of women. Physiological sexual responses to an erotic stimulus were assessed using vaginal photoplethysmography, and subjective reactions were measured using questionnaires. Results suggested a curvilinear relationship between state anxiety and physiological sexual arousal (vaginal pulse amplitude; VPA). Trait anxiety and anxiety sensitivity were correlated with self-reported sexual arousal outside the laboratory. The findings may be interpreted in light of sympathetic nervous system (SNS) influences on sexual arousal and potential cognitive interference mechanisms associated with anxiety. 相似文献
137.
Popularity, social acceptance, and aggression in adolescent peer groups: links with academic performance and school attendance 总被引:1,自引:0,他引:1
This article reports a short-term longitudinal study focusing on popularity and social acceptance as predictors of academic engagement for a sample of 342 adolescents (approximate average age of 14). These youths were followed for 4 consecutive semesters. Popularity, social acceptance, and aggression were assessed with a peer nomination inventory, and data on academic engagement were obtained from school records. For adolescents who were highly aggressive, increases in popularity were associated with increases in unexplained absences and decreases in grade point average. Conversely, changes in social acceptance were not predictive of changes in grade point average or unexplained absences. These results highlight the importance of multidimensional conceptualizations of social standing for research on school adjustment during adolescence and emphasize the potential risks associated with popularity. 相似文献
138.
The factor structure of the Norwegian version of the Dysfunctional Attitude Scale and the Automatic Thoughts Questionnaire was investigated with a sample of 344 male military recruits. Principal factor analyses with promax rotation indicated four factors for the former, labeled Performance Evaluation, Need for Approval, Autonomous Attitude, and Perfectionism which accounted for 15.5%, 3.6%, 2.6%, and 2.5% of the total variance, respectively. Two factors comprised the latter. Factor 1 was labeled Negative Self-concept and Personal Maladjustment and accounted for 40% of the total variance, and Factor 2 was labeled Desire for Change and Negative Expectations and accounted for 6.3% of the total variance. The findings may be useful in identifying the specific dysfunctional beliefs and negative automatic thoughts exhibited by military recruits. Such information can also contribute to the development of more effective treatment interventions. 相似文献
139.
We examined whether a face-inversion effect occurs when participants explore faces by touch. We used a haptic version of the inversion paradigm with 3-D clay facemasks and non-face control objects (teapots) moulded from real objects. Young, neurologically intact, blindfolded participants performed a temporally unconstrained haptic same/different task in each of four stimulus conditions: upright facemasks, inverted facemasks, upright teapots, and inverted teapots. There was a significant inversion effect for faces in terms of accuracy, but none for teapots. The results are considered in terms of the consequences of sequential manual exploration for haptic face processing. 相似文献
140.
In a study of the formation of representations of task sequences and its influence on task inhibition, participants first performed tasks in a predictable sequence (e.g., ABACBC) and then performed the tasks in a random sequence. Half of the participants were explicitly instructed about the predictable sequence, whereas the other participants did not receive these instructions. Task-sequence learning was inferred from shorter reaction times (RTs) in predictable relative to random sequences. Persisting inhibition of competing tasks was indicated by increased RTs in n- 2 task repetitions (e.g., ABA) compared with n- 2 nonrepetitions (e.g., CBA). The results show task-sequence learning for both groups. However, task inhibition was reduced in predictable relative to random sequences among instructed-learning participants who formed an explicit representation of the task sequence, whereas sequence learning and task inhibition were independent in the noninstructed group. We hypothesize that the explicit instructions led to chunking of the task sequence, and that n- 2 repetitions served as chunk points (ABA-CBC), so that within-chunk facilitation modulated the inhibition effect. 相似文献