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The functional significance of learned population differences in male song in the white-crowned sparrow was explored in natural populations using playback tests. Laboratory results have shown that learning of the population-specific song seems to take place in early life and is strongly dependent upon the nature of the auditory experience at that time. However, the varied results of recent studies make it difficult to reach a confident conclusion about the ecological functions of song learning. The present research took advantage of naturally occurring variation in the differences between songs of adjacent populations to determine a function relating degree of difference in song to intensity of territorial singing elicited. Applying a typological evaluation of syllable structure to the four segments of the song allowed a crude quantitative ranking of the differences between local songs and playback stimuli. These results, together with those of other studies, suggest a unimodal aggressive response function of males to songs of other males. A maximum response to songs slightly different from the local song environment suggests that male exclusion based upon acquired song components may contribute to the maintenance of discrete and stable song dialects.  相似文献   
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This paper explains some of the reasoning behind “Can a Good Philosophical Contribution Be Made Just by Asking a Question?,” a paper which consists solely in its title and which is published in the same issue of the journal as the present paper. The method for explaining that reasoning consists in making available a lightly edited version of a letter the authors sent to the editors when submitting the title-only paper. The editors permitted publication of that paper on the condition that the authors also separately publish a version of that letter; the present paper aims to fulfil that condition.  相似文献   
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Social support during an ongoing illness has been shown to be beneficial for both the provider and the receiver, but people often struggle with offering effective, appropriate support. There is a lack of communication-focused training not specifically tied to caregiving or training that is designed for all social network members of a person experiencing a chronic illness, which we call interpersonal support providers (ISPs). We conducted a concurrent mixed-methods needs assessment, surveying both ISPs and support receivers, to understand communicative challenges and inform an evidence-based intervention. Analysis of results from an online survey (Nproviders = 91, Nreceivers = 97), consisting of five open-ended and 15 quantitative items, suggests that ISPs have difficulty managing their worries and emotions while providing comfort to others, which may impact support quality. In addition, ISPs and receivers both identify “listening” as a key skill for ISPs to hone, though ISPs feel they are more skilled at listening than receivers say they are. Lastly, ISPs feel they are good at sharing information and advice, but receivers often perceive it as patronizing or unhelpful. These results will inform the creation of an intervention for everyone offering emotional, esteem, and informational support to individuals with chronic illnesses.  相似文献   
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Given that risk beliefs predict engagement in behaviors to prevent disease, it is important to understand the factors associated with risk beliefs. In the present paper, we conducted path analyses to investigate the associations of belief systems (political orientation and cultural worldviews of individualism and hierarchy) with COVID-19 risk beliefs (i.e., perceived likelihood, perceived severity, and worry about disease; Studies 1 and 2), and the indirect effect through trust in information sources in these relationships (Study 1). Two online panels of U.S. adults were surveyed at three timepoints during the COVID-19 pandemic (Study 1: baseline n = 1,667, 1-year follow-up n = 551; Study 2: n = 404). Results of path analyses indicated that, across studies and timepoints, when controlling for political orientation, trust, and demographic factors, greater individualism had consistent significant direct effects on lower perceived severity and worry about COVID-19, whereas greater hierarchy had consistent significant direct effects on lower perceived severity. However, after accounting for cultural worldviews of individualism and hierarchy (and trust and demographic factors), none of the associations among political orientation and any of the three COVID-19 risk beliefs were significant. The test of indirect effects indicated that individualism and hierarchy were indirectly associated with lower perceived severity of and worry about COVID-19 through less trust. The findings suggest that cultural worldviews of individualism and hierarchy play a role in shaping people's risk beliefs.  相似文献   
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Response latencies were obtained from 10 Ss in auditory signal-detection experiments. The response latencies were inversely related to certainty that a signal was (or was not) presented. The S’s decision criterion was found to have an influence on response latency, which was consistent with the hypothesis that stimuli close to the current criterion elicit longer response latencies than stimuli more distant from the criterion. Comparisons among receiver operating characteristics derived from binary decisions, from the latencies of binary decisions, and from confidence ratings show that response latencies and binary decisions together yield more information about the stimulus than does the binary decision alone. However, the increment in information gained from the measurement of response latencies is in general (though not for every S) smaller than that gained by shifting from yes-no responses to a confidence-rating procedure.  相似文献   
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