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181.
Individuals display high levels of trust and express feelings of safety when interacting with social ingroup members. Here, we investigated whether cues related to ingroup membership would change perceptions of the safety of alcohol. Participants were exposed to images of beer in either a standard can or a can featuring the colors of their university (i.e., ‘fan cans’). We hypothesized that exposure to fan cans would change perceptions of the risks of beer drinking. Results showed that participants exposed to fan cans rated beer consumption as less dangerous (Experiment 1), were more likely to automatically activate safety-related mental content after unconscious perception of beer cues (Experiment 2), and viewed their ingroup's party practices as less dangerous (Experiment 3). These results provide evidence that ingroup-associated colors can serve as a safety cue for alcohol, which may in theory perpetuate alcohol-related risk-taking, already a cause for concern on college and university campuses.  相似文献   
182.
Previous research has shown that rats can learn matching-to-sample relations with olfactory stimuli; however, the specific characteristics of this relational control are unclear. In Experiment 1, 6 rats were trained to either match or nonmatch to sample in a modified operant chamber using common household spices as olfactory stimuli. After matching or nonmatching training with 10 exemplars, the contingencies were reversed with five new stimuli such that subjects trained on matching were shifted to nonmatching and vice versa. Following these reversed contingencies, the effects of the original training persisted for many trials with new exemplars. In Experiment 2, 9 rats were trained with matching procedures in an arena that provided for 18 different spatial locations for comparison stimuli. Five subjects were trained with differential reinforcement outcomes and 4 with only one type of reinforcer. Differential outcomes and multiple exemplars facilitated learning, and there was strong evidence for generalization to new stimuli for most rats that acquired several conditional discriminations. Performances with novel samples were generally above chance, but rarely reached the high levels obtained during baseline with well-trained stimulus relations. However, taken together, the data from the two experiments extend previous work, show that rats can learn both match and nonmatch relations with different experimental protocols, and demonstrate generalization to novel sample stimuli.  相似文献   
183.
Weber  Bruce H. 《Synthese》2011,178(2):271-289
The design argument was rebutted by David Hume. He argued that the world and its contents (such as organisms) were not analogous to human artifacts. Hume further suggested that there were equally plausible alternatives to design to explain the organized complexity of the cosmos, such as random processes in multiple universes, or that matter could have inherent properties to self-organize, absent any external crafting. William Paley, writing after Hume, argued that the functional complexity of living beings, however, defied naturalistic explanations. In effect he dared anyone to come up with an alternative to his inference to design, and hence a designer, outside of nature. Charles Darwin explained the apparent design of functional complexity by his theory of natural selection. Asa Gray, however, in essays as well as in correspondence with Darwin argued that natural selection allowed for a type of ‘evolutionary teleology’ in which design at most could be considered the result of universal principles. F.E. Hicks updated Hume by specifically objecting to the use of design arguments by Paley. Hicks argued that the apparent design seen in nature reflected order at a deep level in nature. The design argument was briefly revived by Lawrence Henderson early in the twentieth century but he ultimately concluded that design and teleology were not necessarily mutually entailing and he retracted his design argument in favor of one that he termed ‘natural teleology’. The current claims of ‘intelligent design’ have the same logical problems that have beset previous design arguments. If design is divorced from teleology and its discontents put behind us, then there is a possibility that the latter can have a place in the development of theories to explain the phenomena of emergent complexity.  相似文献   
184.
185.
Low frequency Repetitive Transcranial Magnetic Stimulation (rTMS) has previously been applied to language homologues in non-fluent populations of persons with aphasia yielding significant improvements in behavioral language function up to 43 months post stimulation. The present study aimed to investigate the electrophysiological correlates associated with the application of rTMS through measurement of the semantic based N400 Event-related brain potentials (ERP) component. Low frequency (1 Hz) rTMS was applied to the anterior portion of the homologue to Broca’s area (pars triangularis), for 20 min per day for 10 days, using a stereotactic neuronavigational system. Twelve non-fluent persons with aphasia, 2-6 years post stroke were stimulated. Six participants were randomly assigned to receive real stimulation and six participants were randomly assigned to receive a blind sham control condition. ERP measures were recorded at baseline, 1 week and 2 months subsequent to stimulation. The findings demonstrate treatment related changes observed in the stimulation group when compared to the placebo control group at 2 months post stimulation indicating neuromodulation of N400 as a result of rTMS. No treatment related changes were identified in the stimulation group, when compared to the sham group from baseline to 1 week post stimulation. The electrophysiological results represent the capacity of rTMS to modulate neural language networks and measures of lexical-semantic function in participants with non-fluent aphasia and suggest that time may be an important factor in brain reorganization subsequent to rTMS.  相似文献   
186.
Children with early developmental delays are at heightened risk for behavior problems and comorbid psychopathology. This study examined the trajectories of regulatory capabilities and their potentially mediating role in the development of behavior problems for children with and without early developmental delays. A sample of 231 children comprised of 137 typically developing children and 94 children with developmental delays were examined during mildly frustrating laboratory tasks across the preschool period (ages 3–5). Results indicated that children with delays had greater use of maladaptive strategies (distraction, distress venting) and lower use of adaptive strategies (constructive coping) than typically developing children. For both groups, strategies had similar rates of growth across time; maladaptive strategies decreased and adaptive strategies increased. The intercept of strategy use, but not the slope, was found to mediate the relation between developmental risk and externalizing behaviors. Findings support that dysregulation, rather than the developmental risk, may be responsible for the high levels of comorbid psychopathology.  相似文献   
187.
Innovation and social learning are the pillars of cultural evolution, allowing cultural behaviours to cumulatively advance over generations. Yet, little is known about individual differences in the use of social and asocial information. We examined whether personality influenced 7-11-year-old children's (N = 282) propensity to elect to observe others first or independently generate solutions to novel problems. Conscientiousness was associated with electing for no demonstrations, while agreeableness was associated with opting for demonstrations. For children receiving demonstrations, openness to experience consistently predicted deviation from observed methods. Children who opted for no demonstrations were also more likely than those opting for demonstrations to exhibit tool manufacture on an innovation challenge and displayed higher creativity, as measured by an alternate uses task. These results highlight how new cultural traditions emerge, establish and advance by identifying which individuals generate new cultural variants in populations and which are influential in the diffusion of these variants, and help reduce the apparent tension within the ‘ratchet’ of cumulative culture.  相似文献   
188.
Eighty-one participants were recruited to test the sensitivity of the mating sociometer to mate-value feedback in the context of ongoing intimate relationships. Experiences of social rejection/acceptance by attractive opposite-sex confederates were manipulated. The effects of this manipulation on self-esteem, relationship satisfaction and commitment, perceptions of dating alternatives, and friendship-dedication were assessed. Social rejection/acceptance by members of the opposite sex altered relationship satisfaction and commitment; this causal link was amplified by changes in state self-esteem; and these effects were specific to intimate relationships and did not generalize to friendship-dedication. This research supports a domain-specific conceptualization of sociometer theory, extending the theory in important directions.  相似文献   
189.
People often assign ownership to the person who has invested labor into making an object (labor rule). However, labor usually improves objects and increases their value, and it has not been investigated whether these considerations underlie people's use of the labor rule. We presented participants with third‐party ownership conflicts between an owner of materials and an artist who used the materials for some artwork. Experiment 1 revealed that participants were more likely to transfer ownership to the artist for low‐value materials than for high‐value materials, and Experiment 2 showed that this effect was further moderated by the amount of effort the artist had invested. A third experiment confirmed that participants transferred ownership more often if the artist's labor had increased the value of the materials than when it had added no value. These findings suggest that considerations for value underlie ownership transfers following the investment of labor.  相似文献   
190.
To assess the validity of the Physical and Mental Component Summary scores (PCS-12 and MCS-12) of the SF-12 Health Survey (SF-12) in an Old Order Mennonite (OOM) community in Ontario, Canada. Most SF-12 validation studies have focused on general populations or clinical groups. This paper adds to the SF-12 literature by validating the instrument in a minority population. Sixty percent of the adult OOM population (n?=?1,171) completed a survey which had the SF-12 embedded within it. The survey also included questions on health determinants and the prevalence of chronic conditions. Factor analysis was used to confirm the two-factor structure of the SF-12. Item-scale correlations were calculated to assess convergent and discriminant validity. PCS-12 and MCS-12 variability by known subgroups were also explored. Factor analysis confirmed the two-factor structure and hypothesized loadings on the latent physical and mental health factors. Item-scale correlations demonstrated satisfactory convergent and discriminant validity. SF-12 summary scores distinguished well, and in the expected manner, between groups of respondents for gender, age, income adequacy, marital status, self-reported health measures, and other health determinants such as coping, trust, social interaction, and spirituality. PCS-12 and MCS-12 scores were lower in those with various chronic conditions compared to those without.The SF-12 appears to be a valid instrument for measuring health status in this minority population. Future SF-12 studies in OOMs and other populations may benefit from using Version 2 of the SF-12, where the dichotomous questions have been replaced by questions offering respondents more choice.  相似文献   
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