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911.
Four experiments examined relapse of extinguished observing behavior of pigeons using a two-component multiple schedule of observing-response procedures. In both components, unsignaled periods of variable-interval (VI) food reinforcement alternated with extinction and observing responses produced stimuli associated with the availability of the VI schedule (i.e., S+). The components differed in the rate of food arranged (Rich = VI 30 s; Lean = VI 120 s). In Experiment 1, following baseline training, extinction of observing involved removal of both food and S+ deliveries, and reinstatement was examined by presenting either response-independent food or S+ deliveries. In Experiment 2, extinction involved removal of only food deliveries while observing responses continued to produce S+. Reinstatement was examined by delivering food contingent upon the first two food-key responses occurring in the presence of the S+. Experiment 3 assessed ABA renewal of observing by extinguishing food-key and observing responses in the presence of one contextual stimulus (i.e., B) and then returning to the original training context (i.e., A) during continued extinction. Experiment 4 examined resurgence by introducing food reinforcement for an alternative response during extinction, and subsequently removing that alternative source of food. Across experiments, relative resistance to extinction and relapse of observing tended to be greater in the component previously associated with the higher rate of primary reinforcement. Relapse of observing or attending to stimuli associated with primary reinforcement appears to be impacted by frequency of primary reinforcement in a manner similar to responding maintained directly by primary reinforcement.  相似文献   
912.
In a sample of 998 ethnically diverse adolescents, a multiagent, multimethod approach to the measurement of adolescent effortful control, adolescent substance use, and friendship influence was used to predict escalations to early-adult tobacco, alcohol, and marijuana use by ages 22-23. Structural equation modeling revealed that adolescent substance use and friends' substance use tended to be highly correlated and together were robust predictors of a problematic pattern of usage for all substances in early adulthood. In addition, the adolescent effortful control construct directly predicted progressions to problematic use of tobacco and marijuana, but not for alcohol. In the alcohol model, effortful control interacted with the construct of substance use lifestyle (based on adolescent alcohol use and friends' substance use) when predicting problematic alcohol use in early adulthood. Results held when comparing across genders and across ethnic groups. These findings emphasize the importance of addressing adolescent self-regulation in interventions designed to treat and prevent early-adult substance abuse.  相似文献   
913.
There is growing evidence that individuation experience is necessary for development of expert object discrimination that transfers to new exemplars. Individuation training in human studies has primarily used label association tasks where labels are learned at both the individual and more abstract (basic) level, and expertise criterion requires that individual-level judgments become as fast as basic-level judgments. However, there are training situations when the use of labels is not practical (e.g., with animals or some clinical populations). Moreover, labeling itself can facilitate object discrimination, thus it is unclear what role labels play in the acquisition of expertise in such training paradigms. Here, participants completed an online game that did not require labels in which they interacted with novel objects (Greebles) or control objects (Yufos). Games either required individuation or categorization. We then assessed the impact of this exposure on an abridged Greeble training paradigm. As expected, participants who played Yufo games or Greeble categorization games showed a significant basic-level advantage for Greebles in the abridged training paradigm, typical of novices. However, participants who played the Greeble identity game showed a reduced basic-level advantage, suggesting that individuation without labels may be sufficient to acquire perceptual expertise.  相似文献   
914.
Laughter is an auditory stimulus that powerfully conveys positive emotion. We investigated how laughter influenced the visual perception of facial expressions. We presented a sound clip of laughter simultaneously with a happy, a neutral, or a sad schematic face. The emotional face was briefly presented either alone or among a crowd of neutral faces. We used a matching method to determine how laughter influenced the perceived intensity of the happy, neutral, and sad expressions. For a single face, laughter increased the perceived intensity of a happy expression. Surprisingly, for a crowd of faces, laughter produced an opposite effect, increasing the perceived intensity of a sad expression in a crowd. A follow-up experiment revealed that this contrast effect may have occurred because laughter made the neutral distractor faces appear slightly happy, thereby making the deviant sad expression stand out in contrast. A control experiment ruled out semantic mediation of the laughter effects. Our demonstration of the strong context dependence of laughter effects on facial expression perception encourages a reexamination of the previously demonstrated effects of prosody, speech content, and mood on face perception, as they may be similarly context dependent.  相似文献   
915.
Primary care medical providers (PCPs) have become de facto providers of services for the management of both mental and chronic illnesses. Although some reports suggest that PCPs favor having Behavioral Health colleagues provide behavioral health services in primary care, others demonstrate this view is necessarily not universal. We examined attitudes regarding behavioral health services among PCPs in practices that offer such services via onsite behavioral health providers (n = 31) and those that do not (n = 62). We compared referral rates and perceived need for and helpfulness of behavioral health colleagues in treating mental health/behavioral medicine issues. In both samples, perceived need was variable (5?C100%), as were PCPs?? views of their own competence in mental health/behavioral medicine diagnosis and treatment. Interestingly, neither sample rated perceived access to behavioral health providers exceptionally high. Referral rates and views about the helpfulness of behavioral health services, except in relation to depression and anxiety, were lower than expected. These results suggest a need for increased collaboration with and education of PCPs about the roles and skills of behavioral health professionals.  相似文献   
916.
The contributions of the hippocampus (HC) and perirhinal cortex (PER) to recognition memory are currently topics of debate in neuroscience. Here we used a rapidly-learned (seconds) spontaneous novel odor recognition paradigm to assess the effects of pre-training N-methyl-D-aspartate lesions to the HC or PER on odor recognition memory. We tested memory for both social and non-social odor stimuli. Social odors were acquired from conspecifics, while non-social odors were household spices. Conspecific odor stimuli are ethologically-relevant and have a high degree of overlapping features compared to non-social household spices. Various retention intervals (5 min, 20 min, 1h, 24h, or 48 h) were used between study and test phases, each with a unique odor pair, to assess changes in novelty preference over time. Consistent with findings in other paradigms, modalities, and species, we found that HC lesions yielded no significant recognition memory deficits. In contrast, PER lesions caused significant deficits for social odor recognition memory at long retention intervals, demonstrating a critical role for PER in long-term memory for social odors. PER lesions had no effect on memory for non-social odors. The results are consistent with a general role for PER in long-term recognition memory for stimuli that have a high degree of overlapping features, which must be distinguished by conjunctive representations.  相似文献   
917.
The joint Simon effect (JSE) is a spatial-compatibility effect that emerges when two people complete complementary components of a Simon task. In typical JSE studies, two participants sit beside each other and perform go-no-go tasks in which they respond to one of two stimuli by pressing a button. According to the action co-representation account, JSEs emerge because each participant represents their partner's response in addition to their own, causing the same conflicts in processing that would occur if an individual responded to both stimuli (i.e., as in a two-choice task). Because the response buttons are typically in front of participants, however, an alternative explanation is that JSEs are the result of a dimensional overlap between target and response locations coded with respect to another salient object (e.g., the co-actor's effector). To contrast these hypotheses, the participants in the present study completed two-choice and joint Simon tasks in which they were asked to focus on generating an aftereffect in the space contralateral to their response. Hommel (Psychological Research 55:270-279, 1993) previously reported that, when participants completed a two-choice task under such effect-focused instructions, spatial-compatibility effects emerged that were based on the aftereffect location instead of the response location. Consistent with the co-representation account, the results of the present study were that an inverse aftereffect-based (i.e., not a response-location-based) compatibility effect was observed in both the two-choice and joint tasks. The overall pattern of results does not fit with the spatial-coding account and is discussed in the context of the extant JSE literature.  相似文献   
918.
Many animals use spatial memory. Although much work has examined the accuracy of spatial memory, few studies have explicitly focused on its longevity. The importance of long-term spatial memory for foraging has been demonstrated in several cases. However, the importance of such long-term memory for all animals is unclear. In this study, we present the first evidence that a parid species (the black-capped chickadee, Poecile atricapillus) can remember the location of a single food item for at least 6 months under an associative-learning spatial memory paradigm with multiple reinforcements. We did not detect a significant difference in memory longevity between two populations of chickadees shown previously to differ in short-term spatial memory and hippocampal morphology, an area of the brain involved in spatial memory. Our study showed that small birds such as parids can maintain spatial memories for long periods, a feat shown previously only in corvids. Moreover, we were able to demonstrate this longevity within the context of only 16 repeated trials. We speculate that this ability may potentially be useful in relocating caches if reinforced by repeated visits. Future studies are necessary to test whether our results were specifically due to multiple reinforcements of the food-containing location and whether parids may have similar memory longevity during food-caching experiences in the wild.  相似文献   
919.
It has been suggested that action possibility judgements are formed through a covert simulation of the to-be-executed action. We sought to determine whether the motor system (via a common coding mechanism) influences this simulation, by investigating whether action possibility judgements are influenced by experience with the movement task (Experiments 1 and 2) and current body states (Experiment 3). The judgement task in each experiment involved judging whether it was possible for a person's hand to accurately move between two targets at presented speeds. In Experiment 1, participants completed the action judgements before and after executing the movement they were required to judge. Results were that judged movement times after execution were closer to the actual execution time than those prior to execution. The results of Experiment 2 suggest that the effects of execution on judgements were not due to motor activation or perceptual task experience-alternative explanations of the execution-mediated judgement effects. Experiment 3 examined how judged movement times were influenced by participants wearing weights. Results revealed that wearing weights increased judged movement times. These results suggest that the simulation underlying the judgement process is connected to the motor system, and that simulations are dynamically generated, taking into account recent experience and current body state.  相似文献   
920.
In this study we investigated the mediated influence of core self-evaluations (CSE) on employee health problems via job satisfaction and work stress, and the degree to which genetic factors explain these mediated relationships. Based on data obtained from a sample of 594 Swedish twins (114 monozygotic twin pairs and 183 dizygotic twin pairs), conventional path analysis results supported the mediated effects of CSE on employee health via job satisfaction and work stress, after controlling for conscientiousness and extraversion. Behavioral genetic analyses showed significant heritability of all four variables. Moreover, we found that the mediated relationships via job satisfaction and work stress are explained by genetic factors, such that the genetic source of job satisfaction and work stress mediates the genetic influence of CSE on health problems. These results highlight the role played by genetic factors in better understanding the relationships between CSE, work attitudes, and health outcomes.  相似文献   
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