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161.
162.
Animal communication systems have become closely tuned to local habitat conditions as populations have adjusted to different long-term environmental pressures. However, many habitats are now rapidly changing because of anthropogenic modification. Maintenance of effective communication systems in greatly altered environments will depend on communicative responses on both evolutionary and ontogenetic time scales. Consideration of potential acoustic challenges caused by human-generated habitat modification has important implications for basic research and conservation biology. First, the observed signal structure of individuals in altered environments may not match the normally hypothesized call structure. Second, species that either possess little ability to adapt quickly on an evolutionary time scale or have little plasticity in their communicative systems may be unable to respond to large anthropogenic alterations in their acoustic environment. 相似文献
163.
Dodge KA Laird R Lochman JE Zelli A;Conduct Problems Prevention Research Group 《心理评价》2002,14(1):60-73
Social information processing (SIP) patterns were conceptualized in orthogonal domains of process and context and measured through responses to hypothetical vignettes in a stratified sample of 387 children (50% boys; 49% minority) from 4 geographical sites followed from kindergarten through 3rd grade. Multidimensional, latent-construct, confirmatory factor analyses supported the within-construct internal consistency, cross-construct discrimination, and multidimensionality of SIP patterns. Contrasts among nested structural equation models indicated that SIP constructs significantly predicted children's aggressive behavior problems as measured by later teacher reports. The findings support the multidimensional construct validity of children's social cognitive patterns and the relevance of SIP patterns in children's aggressive behavior problems. 相似文献
164.
Spatial learning and memory is preserved in rats after early development in a microgravity environment 总被引:1,自引:0,他引:1
This study evaluated the cognitive mapping abilities of rats that spent part of their early development in a microgravity environment. Litters of male and female Sprague-Dawley rat pups were launched into space aboard the National Aeronautics and Space Administration space shuttle Columbia on postnatal day 8 or 14 and remained in space for 16 days. These animals were designated as FLT groups. Two age-matched control groups remained on Earth: those in standard vivarium housing (VIV) and those in housing identical to that aboard the shuttle (AGC). On return to Earth, animals were tested in three different tasks that measure spatial learning ability, the Morris water maze (MWM), and a modified version of the radial arm maze (RAM). Animals were also tested in an open field apparatus to measure general activity and exploratory activity. Performance and search strategies were evaluated in each of these tasks using an automated tracking system. Despite the dramatic differences in early experience, there were remarkably few differences between the FLT groups and their Earth-bound controls in these tasks. FLT animals learned the MWM and RAM as quickly as did controls. Evaluation of search patterns suggested subtle differences in patterns of exploration and in the strategies used to solve the tasks during the first few days of testing, but these differences normalized rapidly. Together, these data suggest that development in an environment without gravity has minimal long-term impact on spatial learning and memory abilities. Any differences due to development in microgravity are quickly reversed after return to earth normal gravity. 相似文献
165.
Moral psychology has long focused on reasoning, but recent evidence suggests that moral judgment is more a matter of emotion and affective intuition than deliberate reasoning. Here we discuss recent findings in psychology and cognitive neuroscience, including several studies that specifically investigate moral judgment. These findings indicate the importance of affect, although they allow that reasoning can play a restricted but significant role in moral judgment. They also point towards a preliminary account of the functional neuroanatomy of moral judgment, according to which many brain areas make important contributions to moral judgment although none is devoted specifically to it. 相似文献
166.
Previous research indicates that perceived orientation and/or alignment of segments and points can vary as a function of the angular position of the stimulus elements. Several studies show that the variability of the responses is least and accuracy of judgment is greatest where segments and dots are aligned with a cardinal axis. Additionally, some report assimilation of judgments toward the nearest cardinal axis--that is, the segments (or dots) are seen as being closer to the horizontal or vertical than is true. The present research confirms that judgments of collinearity are least variable and most accurate when the segment being judged is aligned with a cardinal axis. However, we do not find any consistent tendency for cardinal axis assimilation. Plotting the collinearity error (delta) as a function of angular position (phi), we find a distinctive profile of oscillation for each subject. Furthermore, subjects who were evaluated in two sessions showed very similar profiles of delta oscillation from Day 1 to Day 2. Harmonic analysis indicated a wide-ranging pattern of significant components. The components at the 4th harmonic and below were more likely to be significant, but each subject showed differential loadings in terms of which of the components were significant, as well as in the sign and amplitude of significant components. These results may reflect idiosyncratic fixation tendencies, or individual differences in the design of neural mechanisms that encode the angular positions of stimuli. 相似文献
167.
Forster KI 《Memory & cognition》2000,28(7):1109-1115
Word recognition experiments that involve comparisons between two different matched sets of words allow for possible experimenter bias if there are many equally well-matched pairs to choose from. The possible extent of this bias depends on the experimenter's intuitive knowledge of the likely difficulty of individual items. This is assessed by asking a number of experimenters to decide which of two frequency-matched words would produce the fastest reaction time in a lexical decision experiment, and then comparing their predictions with actual data. All experimenters demonstrated substantial above-chance accuracy, which was unrelated to the amount of experience they had in the field. It was concluded that the experimenters could potentially produce spurious effect sizes ranging from 16 to 38 msec. 相似文献
168.
Maton KI 《American journal of community psychology》2000,28(1):25-57
A multidisciplinary and multilevel framework for social transformation is proposed, encompassing four foundational goals: capacity-building, group empowerment, relational community-building, and culture-challenge. Intervention approaches related to each goal are presented at the setting, geographic community, and societal levels. Four exemplars of social transformation work are then discussed: the Accelerated Schools Project, Meyerhoff Program, ManKind Project, and women's movement. These examples illustrate the synergistic relationship among the four transformational goals, within and across levels of analysis, which is at the heart of the social transformation process. The paper concludes with three challenges to guide our efforts as we enter the new century: (1) to move social transformation to the center of our consciousness as a field; (2) to articulate jointly with allied disciplines, organizations, and citizen groups an encompassing, multidisciplinary, and multilevel framework for social transformation; and (3) to do the above with heart, soul, and humility. 相似文献
169.
170.
Gellis LA Lichstein KL Scarinci IC Durrence HH Taylor DJ Bush AJ Riedel BW 《Journal of abnormal psychology》2005,114(1):111-118
This investigation compared the likelihood of insomnia and insomnia-related health consequences among individuals of different socioeconomic status. A random-digit dialing procedure was used to recruit at least 50 men and 50 women in each age decade from 20 to 80+ years old. Participants completed 2 weeks of sleep diaries as well as questionnaires related to fatigue, sleepiness, and psychological distress. Socioeconomic status was measured by education status assessed at 3 different levels: individual, household, and community. Results indicated that individuals of lower individual and household education were significantly more likely to experience insomnia even after researchers accounted for ethnicity, gender, and age. Additionally, individuals with fewer years of education, particularly those who had dropped out of high school, experienced greater subjective impairment because of their insomnia. 相似文献