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981.
Delay discounting is the process by which a commodity loses value as the delay to its receipt increases. Rapid discounting predicts various maladaptive behaviors including tobacco use. Typically, delay discounting of different outcomes has been compared between cigarette smokers and nonsmokers. To better understand the relationship of delay discounting to different modes of tobacco use, we examined the differences in delay discounting of different outcomes between cigarette smokers, smokeless tobacco users, e-cigarette users, and non-tobacco users. In the present study, all participants completed 8 titrating delay-discounting tasks: $100 gain, $500 gain, $500 loss, alcohol, entertainment, food, a temporary health gain, and a temporary cure from a disease. Non-tobacco users discounted most outcomes less than tobacco users overall; however, there were no differences in discounting among the different types of tobacco users. These results suggest that nicotine consumption of any kind is associated with a higher degree of impulsivity compared to non-tobacco users. Adoption of tobacco products that have been perceived as less harmful (e.g., e-cigarettes) is not associated with a baseline difference or decrease in delay discounting if adopted after a history of cigarette use.  相似文献   
982.
The present study examined resurgence of reinforced variability in college students, who completed a 3-phase computer-based variability task. In the first phase, baseline, points were delivered for drawing rectangles that sufficiently differed from previous rectangles in terms of a target dimension (size or location, counterbalanced) but were sufficiently similar in terms of the alternative dimension. In the second phase, alternative, points were only delivered for rectangles that were sufficiently different in terms of the alternative dimension, but repetitive in terms of the target dimension. In the third phase, extinction, no points were delivered. In baseline, participants made rectangles that were highly varied in terms of the target dimension and less varied in terms of the alternative dimension, and vice versa in the alternative phase. During extinction, levels of variability increased for the target dimension, providing evidence for resurgence of reinforced variability of a specific dimension of behavior. However, levels of variability also remained high for the alternative dimension, indicating that extinction-induced response variability may also have impacted the results. Although future research is needed to explore other explanations, the results of this study replicate prior research with pigeons and provide some support for the notion of variability as an operant.  相似文献   
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All accounts of language acquisition agree that, by around age 4, children’s knowledge of grammatical constructions is abstract, rather than tied solely to individual lexical items. The aim of the present research was to investigate, focusing on the passive, whether children’s and adults’ performance is additionally semantically constrained, varying according to the distance between the semantics of the verb and those of the construction. In a forced-choice pointing study (Experiment 1), both 4- to 6-year olds (N = 60) and adults (N = 60) showed support for the prediction of this semantic construction prototype account of an interaction such that the observed disadvantage for passives as compared to actives (i.e., fewer correct points/longer reaction time) was greater for experiencer-theme verbs than for agent-patient and theme-experiencer verbs (e.g., Bob was seen/hit/frightened by Wendy). Similarly, in a production/priming study (Experiment 2), both 4- to 6-year olds (N = 60) and adults (N = 60) produced fewer passives for experiencer-theme verbs than for agent-patient/theme-experiencer verbs. We conclude that these findings are difficult to explain under accounts based on the notion of A(rgument) movement or of a monostratal, semantics-free, level of syntax, and instead necessitate some form of semantic construction prototype account.  相似文献   
984.

Human immunodeficiency virus (HIV) continues to be a prominent health and social justice issue, especially for African American communities in the Southern United States. Gender role norms, specifically within faith-based communities in the South, pose challenges to empowering women to make safer sexual health decisions. To explore perceptions of gender norms and sexual health, 42 qualitative interviews were gathered from female members of 16 predominantly African American churches in Atlanta, GA. Constructs from the theory of gender and power and the social ecological model were used to guide coding and analysis. Participants discussed their experiences with gender norms and gender-based power differentials at the institutional (i.e., church), familial, and interpersonal (i.e., intimate relationship) levels. Because of the attitudes and beliefs held by their religious communities and families, many participants recalled struggling to assert themselves in sexual relationships and recalled engaging in risky and unwanted sexual behavior, especially during their young adult years. However, as the participants matured, they worked to overturn traditional gender norms, empowering both their children and women in their religious communities to make healthy, autonomous sexual decisions. Moving forward, participants want their churches and members of their faith communities to play an active role in the empowerment of African American women and provide them with the confidence and education necessary to negotiate sexual decisions with their partners.

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985.
Right hemisphere-damaged (RHD) and left hemisphere-damaged (LHD) aphasic patients were tested on a nonverbal cartoon completion task that included a humorous (Joke) and a nonhumorous (Story) condition. In both conditions, RHD patients performed worse than LHD patients. More importantly, the qualitative difference between the errors produced by the two groups suggests that right and left hemisphere brain damage impairs different components of narrative ability. RHD patients showed a preserved sensitivity to the surprise element of humor, and a diminished ability to establish coherence. Conversely, LHD patients, when they erred, showed an impaired sensitivity to the surprise element of humor, and a preserved ability to establish coherence by integrating content across parts of a narrative. These results suggest that the observed humor comprehension deficits of RHD patients result specifically from right hemisphere disease and not from brain damage irrespective of locus. The performances of the RHD and LHD patients groups together support a separation of narrative ability from the traditional aspects of language ability typically disrupted in aphasia.  相似文献   
986.
Inference deficits in right brain-damaged patients   总被引:5,自引:6,他引:5  
The inferential reasoning ability of right hemisphere-damaged (RHD) patients was tested by presenting pairs of sentences which were to be treated as single, integrated units. The two sentences treated together made one interpretation likely (a correct inference); one of the sentences in isolation encouraged a different interpretation (an incorrect inference). The position of the misleading sentence was systematically varied. Results showed that, in contrast to normal controls, RHD patients have more trouble answering inference questions, especially those concerning incorrect inferences, than answering questions about the factual content of the passages. Also, RHD patients made significantly more errors when the misleading information was contained in the first rather than in the second sentence; this finding indicates that these patients have difficulty revising previously acquired knowledge in light of new information. These results suggest the impairment of several components of normal discourse processing subsequent to right hemisphere brain damage.  相似文献   
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