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881.
Participants were presented with sentences mentioning an entity with a typical location in the upper or lower vertical space (e.g., roof vs. root). Sentences supported or reversed the typical location of the target entity. Sensibility judgments requiring upwards or downwards responses were faster when the response matched rather than mismatched the target entity's typical location. This compatibility effect was independent of whether the sentence context supported or reversed the target entity's typical location. The results, therefore, provide clear evidence for word-based but no evidence for sentence-based simulation processes. 相似文献
882.
A smile may communicate different communicative intentions depending on subtle characteristics of the facial expression. In this article, we propose an algorithm to determine the morphological and dynamic characteristics of virtual agent's smiles of amusement, politeness, and embarrassment. The algorithm has been defined based on a virtual agent's smiles corpus constructed by users and analyzed with a decision tree classification technique. An evaluation, in different contexts, of the resulting smiles has enabled us to validate the proposed algorithm. 相似文献
883.
Spatial reference in multiple object tracking is available from configurations of dynamic objects and static reference objects. In three experiments, we studied the use of spatial reference in tracking and in relocating targets after abrupt scene rotations. Observers tracked 1, 2, 3, 4, and 6 targets in 3D scenes, in which white balls moved on a square floor plane. The floor plane was either visible thus providing static spatial reference or it was invisible. Without scene rotations, the configuration of dynamic objects provided sufficient spatial reference and static spatial reference was not advantageous. In contrast, with abrupt scene rotations of 20°, static spatial reference supported in relocating targets. A wireframe floor plane lacking local visual detail was as effective as a checkerboard. Individually colored geometric forms as static reference objects provided no additional benefit either, even if targets were centered on these forms at the abrupt scene rotation. Individualizing the dynamic objects themselves by color for a brief interval around the abrupt scene rotation, however, did improve performance. We conclude that attentional tracking of moving targets proceeds within dynamic configurations but detached from static local background. 相似文献
884.
Recent studies on the conceptualization of abstract concepts suggest that the concept of time is represented along a left-right horizontal axis, such that left-to-right readers represent past on the left and future on the right. Although it has been demonstrated with strong consistency that the localization (left or right) of visual stimuli could modulate temporal judgments, results obtained with auditory stimuli are more puzzling, with both failures and successes at finding the effect in the literature. The present study supports an account based on the relative relevance of visual versus auditory-spatial information in the creation of a frame of reference to map time: The auditory location of words interacted with their temporal meaning only when auditory information was made more relevant than visual spatial information by blindfolding participants. 相似文献
885.
Behavioral activation that is associated with incentive-reward motivation increases in adolescence relative to childhood and adulthood. This quadratic developmental pattern is generally supported by behavioral and experimental neuroscience findings. It is suggested that a focus on changes in dopamine neurotransmission is informative in understanding the mechanism for this adolescent increase in reward-related behavioral activation and subsequent decline into adulthood. Evidence is presented to indicate that incentive-reward motivation is modulated by mesoaccumbens dopamine, and that it increases in adolescence before declining into adulthood because of normative developmental changes at the molecular level. Potential mechanisms of variation in functional mesoaccumbens dopamine transmission are discussed with a focus on the interplay between tonic and phasic modes of dopamine transmission in modulating both general incentive-motivational biases and the efficacy of reward learning during exposure to novel reward experiences. Interactions between individual difference factors and these age-related trends are discussed. 相似文献
886.
887.
Factor analytic studies of the structure of self-reported posttraumatic stress disorder (PTSD) symptoms have consistently supported two 4-factor models; the "Dysphoria" and the "Emotional Numbing" model. The fit of both models has been satisfactory; however, it has been difficult to unequivocally determine which model is best. This study aimed to test the hypothesis that there is no single "correct" model, but rather that the models represent different subpopulations. A confirmatory factor 2-class mixture model was specified with the Dysphoria model in one class and the Emotional Numbing model in the other. This model was tested using data from participants from 4 trauma groups. This model fitted the data better than 1 and 2-class models of the Dysphoria, Emotional Numbing, and cross-factor loading model. It was concluded that the search for the "correct" model of PTSD based on the assumption of a single homogenous population may not be a worthwhile research endeavor. (PsycINFO Database Record (c) 2012 APA, all rights reserved). 相似文献
888.
Friend influence over alcohol intoxication and delinquent behavior was examined as a function of relative peer acceptance in a 3-year study of Swedish youth (N = 184 girls, 145 boys). Participants were in the first year of secondary school (7th grade, M = 11.7 years old) or the first year of high school (10th grade, M = 15.3 years old) at the outset. Friends resembled one another before the friendship; resemblances were even greater after the friendship began. Resemblances continued to grow among those who remained friends one year later, but declined among those whose friendships dissolved. Partners were not equally responsible for increases in similarity. In stable friendships, the more accepted partner exerted greater influence over the less accepted partner, such that the greatest increases in problem behaviors were found among less accepted youth whose friends had higher initial levels of delinquency and alcohol intoxication. Unstable friends resembled random pairs of youth in that more- and less-accepted partners were comparably uninfluential. 相似文献
889.
Alloy LB Urošević S Abramson LY Jager-Hyman S Nusslock R Whitehouse WG Hogan M 《Journal of abnormal psychology》2012,121(1):16-27
Little longitudinal research has examined progression to more severe bipolar disorders in individuals with "soft" bipolar spectrum conditions. We examine rates and predictors of progression to bipolar I and II diagnoses in a nonpatient sample of college-age participants (n = 201) with high General Behavior Inventory scores and childhood or adolescent onset of "soft" bipolar spectrum disorders followed longitudinally for 4.5 years from the Longitudinal Investigation of Bipolar Spectrum (LIBS) project. Of 57 individuals with initial cyclothymia or bipolar disorder not otherwise specified (BiNOS) diagnoses, 42.1% progressed to a bipolar II diagnosis and 10.5% progressed to a bipolar I diagnosis. Of 144 individuals with initial bipolar II diagnoses, 17.4% progressed to a bipolar I diagnosis. Consistent with hypotheses derived from the clinical literature and the Behavioral Approach System (BAS) model of bipolar disorder, and controlling for relevant variables (length of follow-up, initial depressive and hypomanic symptoms, treatment-seeking, and family history), high BAS sensitivity (especially BAS Fun Seeking) predicted a greater likelihood of progression to bipolar II disorder, whereas early age of onset and high impulsivity predicted a greater likelihood of progression to bipolar I (high BAS sensitivity and Fun-Seeking also predicted progression to bipolar I when family history was not controlled). The interaction of high BAS and high Behavioral Inhibition System (BIS) sensitivities also predicted greater likelihood of progression to bipolar I. We discuss implications of the findings for the bipolar spectrum concept, the BAS model of bipolar disorder, and early intervention efforts. 相似文献
890.
This experiment investigated social referencing as a form of discriminative learning in which maternal facial expressions signaled the consequences of the infant's behavior in an ambiguous context. Eleven 4- and 5-month-old infants and their mothers participated in a discrimination-training procedure using an ABAB design. Different consequences followed infants' reaching toward an unfamiliar object depending on the particular maternal facial expression. During the training phases, a joyful facial expression signaled positive reinforcement for the infant reaching for an ambiguous object, whereas a fearful expression signaled aversive stimulation for the same response. Baseline and extinction conditions were implemented as controls. Mothers' expressions acquired control over infants' approach behavior for all participants. All participants ceased to show discriminated responding during the extinction phase. The results suggest that 4- and 5-month-old infants can learn social referencing via discrimination training. 相似文献