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981.
In three experiments rats were given serial preexposure to two flavor stimuli. In Experiment 1, some animals were given exposure to AX followed by the presentation of BX, a forward schedule; the others were given backward preexposure (BX→AX). Conditioning and test trials with the A element showed that salience or effectiveness of A was better protected in the forward than in the backward condition. Experiments 2 and 3 assessed the relevance of this salience modulation mechanism for perceptual learning. In these experiments, generalization of a conditioned aversion from AX to BX was reduced in the forward (but not in the backward) condition only after prolonged exposure, indicating that the establishment of an inhibitory link from B to A is required for successful discrimination. However, generalization to a novel compound stimulus, NX, was reduced in the forward group both after short and long preexposure, suggesting the existence of salience modulation processes that work in parallel with associative inhibition. These results seem to support the existence of a salience modulation mechanism that seems to be beyond the scope of current theories of perceptual learning.  相似文献   
982.
This study aimed to evaluate the type of attentional selection (location- and/or object-based) triggered by two different types of central noninformative cues: eye gaze and arrows. Two rectangular objects were presented in the visual field, and subjects' attention was directed to the end of a rectangle via the observation of noninformative directional arrows or eye gaze. Similar experiments with peripheral cues have shown an object-based effect: faster target identification when the target is presented on the cued object as compared to the uncued object, even when the distance between target and cue was the same. The three reported experiments aimed to compare the location- and object-based attentional orienting observed with arrows and eye gaze, in order to dissociate the orienting mechanisms underlying the two types of orienting cues. Results showed similar cueing effects on the cued versus oppositely cued locations for the two cue types, replicating several studies with nonpredictive gaze and arrow cues. However, a pure object-based effect occurred only when an arrow cue was presented, whereas a pure location-based effect was only found for eye-gaze cues. It is suggested that attention is nonspecifically directed to nearby objects when a noninformative arrow is used as cue, whereas it is selectively directed to a specific cued location when noninformative eye gaze is used. This may be mediated by theory of mind mechanisms.  相似文献   
983.
Systematic errors in time reproduction tasks have been interpreted as a misperception of time and therefore seem to contradict basic assumptions of pacemaker-accumulator models. Here we propose an alternative explanation of this phenomenon based on methodological constraints regarding the direction of time, which cannot be manipulated in experimental settings. In two experiments, we demonstrate the influence of the direction of a dimensional change for pitch and brightness estimates. The results support the assumption that errors in time reproduction tasks do not reflect a systematic temporal misperception, but rather a methodological artifact. Implications for contemporary models of time perception are discussed. (PsycINFO Database Record (c) 2012 APA, all rights reserved).  相似文献   
984.
A residential treatment program has been developed specifically for substance-abusing pregnant and parenting women in Finland, focusing on simultaneously supporting maternal abstinence from substances and the mother-baby relationship. The aims of the study are to explore maternal pre- and postnatal reflective functioning and its association with background factors, maternal exposure to trauma, and psychiatric symptoms, postnatal interaction, child development, and later child foster care placement. Participants were 34 mother-baby pairs living in three residential program units during the pre- to postnatal period. We employed self-report questionnaires on background, trauma history, and psychiatric symptoms (Brief Symptom Inventory: L.R. Derogatis, 1993; Edinburgh Postnatal Depression Scale: J.L. Cox, J.M. Holden, & R. Sagovsky, 1987; Traumatic Antecedents Questionnaire: B. Van der Kolk, 2003), videotaped mother-child interactions coded for sensitivity, control, and unresponsiveness (Care Index for Infants and Toddlers: P. Crittenden, 2003); a standardized test of child development (Bayley Scales of Infant Development-II: N. Bayley, 1993); and semistructured interviews for maternal reflective functioning (Pregnancy Interview: A. Slade, E. Bernbach, J. Grienenberger, D.W. Levy, & A. Locker, 2002; Parent Development Interview: A. Slade et al., 2005). Pre- and postnatal maternal reflective functioning (RF) was on average low, but varied considerably across participants. Average RF increased significantly during the intervention. Increase in RF level was found to be associated with type of abused substance and maternal trauma history. Mothers who showed lower postnatal RF levels relapsed to substance use more often after completing a residential treatment period, and their children were more likely to be placed in foster care. The intensive focus on maternal RF is an important direction in the development of efficacious treatment for this very high risk population.  相似文献   
985.
Fincher & Thornhill (F&T) present a model of in-group assortative sociality resulting from differing levels of parasite-stress in differing geographical locations in the United States and the world. Their model, while compelling, overlooks some important issues, such as mutualistic associations with parasites that are beneficial to humans and how some religious practices increase parasite risk.  相似文献   
986.
In four experiments we assessed whether visual working memory (VWM) maintains a record of previously processed visual information, allowing old information to be inhibited, and new information to be prioritized. Specifically, we evaluated whether VWM contributes to the inhibition (i.e., visual marking) of previewed distractors in a preview search. We evaluated this proposal by testing three predictions. First, Experiments 1 and 2 demonstrate that preview inhibition is more effective when the number of previewed distractors is below VWM capacity than above; an effect that can only be observed at small preview set sizes (Experiment 2A) and when observers are allowed to move their eyes freely (Experiment 2B). Second, Experiment 3 shows that, when quantified as the number of inhibited distractors, the magnitude of the preview effect is stable across different search difficulties. Third, Experiment 4 demonstrates that individual differences in preview inhibition are correlated with individual differences in VWM capacity. These findings provide converging evidence that VWM supports the inhibition of previewed distractors. More generally, these findings demonstrate how VWM contributes to the efficiency of human visual information processing--VWM prioritizes new information by inhibiting old information from being reselected for attention.  相似文献   
987.
According to the moral licensing literature, moral self-perceptions induce compensatory behavior: People who feel moral act less prosocially than those who feel immoral. Conversely, work on moral identity indicates that moral self-perceptions motivate behavioral consistency: People who feel moral act more prosocially than those who feel less so. In three studies, the authors reconcile these propositions by demonstrating the moderating role of conceptual abstraction. In Study 1, participants who recalled performing recent (concrete) moral or immoral behavior demonstrated compensatory behavior, whereas participants who considered temporally distant (abstract) moral behavior demonstrated behavioral consistency. Study 2 confirmed that this effect was unique to moral self-perceptions. Study 3 manipulated whether participants recalled moral or immoral actions concretely or abstractly, and replicated the moderation pattern with willingness to donate real money to charity. Together, these findings suggest that concrete moral self-perceptions activate self-regulatory behavior, and abstract moral self-perceptions activate identity concerns.  相似文献   
988.
The authors extended research linking individual differences in consideration of future consequences (CFC) with health behaviors by (a) testing whether individual differences in regulatory focus would mediate that link and (b) highlighting the value of a revised, two-factor CFC-14 scale with subscales assessing concern with future consequences (CFC-Future) and concern with immediate consequences (CFC-Immediate) proper. Exploratory and confirmatory factor analyses of the revised CFC-14 scale supported the presence of two highly reliable factors (CFC-Future and CFC-Immediate; αs from .80 to .84). Moreover, structural equation modeling showed that those high in CFC-Future engage in exercise and healthy eating because they adopt a promotion orientation. Future use of the two-factor CFC-14 scale is encouraged to shed additional light on how concern with future and concern with immediate consequences (proper) differentially impact the way people resolve a host of intertemporal dilemmas (e.g., health, financial, and environmental behavior).  相似文献   
989.
In human and non-human animals the steroid hormones cortisol and testosterone are involved in social aggression and recent studies suggest that these steroids might jointly regulate this behavior. It has been hypothesized that the imbalance between cortisol and testosterone levels is predictive for aggressive psychopathology, with high testosterone to cortisol ratio predisposing to a socially aggressive behavioral style. In this review, we focus on the effects of cortisol and testosterone on human social aggression, as well as on how they might modulate the aggression circuitry of the human brain. Recently, serotonin is hypothesized to differentiate between impulsive and instrumental aggression, and we will briefly review evidence on this hypothesis. The aim of this article is to provide a theoretical framework for the role of steroids and serotonin in impulsive social aggression in humans.  相似文献   
990.
Three experiments are reported on the development of object categorization skills during the second year of life. Experiment 1 examined whether 14- and 18-month-old infants were capable of performing categorization at the animate/inanimate (A/I) level using a sequential touching task. The 18-month-olds were significantly above chance and the 14-month-olds were also approaching above-chance significance, which is the highest level of inclusiveness ever tested in infancy. In Experiments 2 and 3, 14-month-old infants participated in a sequential touching task in which the part features of animate and inanimate objects were modified, allowing for a test of partonomic (i.e., legs and wheels) vs. taxonomic (i.e., animates and inanimates) categorization. Infants did not favor partonomic categorization, suggesting that A/I categories are not formed solely based on object parts such as legs and wheels.  相似文献   
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