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21.
22.
视觉短时存贮(STVS)的时间特性已得到广泛研究。本文采用G.Sperling首创的部分报告方法,对STVS的一些空间特性进行了研究。实验一研究了视觉信息的空间广度和密度对于STVS的影响。实验二研究了STVS中的参照系问题。结果表明:(一)信息广度对STVS没有影响,而信息密度的增加对STVS有负影响。(二)视网膜参照系是STVS最基本的参照系,空间参照系只在特定条件下才起作用。文中对这些结果给出了解释。 相似文献
23.
立体视觉的心理物理和VEP比较研究 总被引:2,自引:0,他引:2
心理物理试验是研究立体视觉的主要方法。70年代VEP开始用于体视研究,并取得许多结果。由于VEP信号复杂,这些结果不能令人满意。本文使用心理物理试验和VEP对比方法对体视加以研究。我们的结果是:VEP波形中第一个正峰与刺激图形的亮度有关;N_2峰和P_3峰的潜伏期对判断体视存在与否有重要价值;本试验确定N_2峰潜伏期在体视存在时约为240ms—280ms,无体视存在时约为290ms—310ms;P_3峰潜伏期在体视存在时约为280ms—310ms,无体视存在时约为340ms—360ms;体视存在时的VEP与无体视存在时的VEP的互相关系数小于0.1;有体视的VEP其功率谱密度在8Hz附近有一峰;心理物理试验中使用强制选择得到的结果从VEP波形比较中可以确认是可靠的;有体视的VEP其N_2和P_3的潜伏期随视差变化呈现规律性改变。 相似文献
24.
Alternation behavior, spatial discrimination, and reversal disturbances following 6-hydroxydopamine lesions in the nucleus accumbens of the rat 总被引:3,自引:0,他引:3
K Taghzouti A Louilot J P Herman M Le Moal H Simon 《Behavioral and neural biology》1985,44(3):354-363
The effects of dopaminergic depletion of the nucleus accumbens was tested in various behavioral tasks such as alternation, spatial discrimination, and reversal learning, and in an extinction paradigm in a T maze. Animals with lesions showed impairment of spontaneous alternation behavior, disturbances in the acquisition of spatial discrimination, and great difficulty in reversing previously learned habits. In the extinction phase, experimental animals are unable to adjust their behavior, and continue to choose the previously reinforced arm of the T maze. It is suggested that the nucleus accumbens plays an important role in the transition of motivation into action, and that dopamine has a facilitatory influence on the mediation of these processes. 相似文献
25.
Disturbances in exploratory behavior and functional recovery in the Y and radial mazes following dopamine depletion of the lateral septum 总被引:1,自引:0,他引:1
The effects of 6-hydroxydopamine (6-OHDA) injected into the lateral septum in rats were investigated for spontaneous alternation behavior in a Y maze and for spatially oriented behavior in an 8-arm radial maze. The performance of the animals in these tests was assessed under two physiological states, food-satiated and food-deprived. The selective depletion of septal dopaminergic concentrations leads to behavioral disturbances in both the Y and the radial mazes. These deficits disappeared when the animals with 6-OHDA lesions were food-deprived. These results confirm other studies from our laboratory and support two conclusions. First, lesions of dopaminergic neurons lead to behavioral impairments which resemble those found after the total lesion of the structure they innervate. Second, these behavioral impairments are responsive to therapeutic treatments, manipulations of the internal or external environment, or the level of arousal, since under certain conditions a recovery of function can occur in the absence of dopaminergic neurons. These two points provide additional support for a nonspecific role for the dopaminergic neurons originating in the ventral tegmental area. These neurons could have a permissive role in the functioning of the forebrain structures they innervate. 相似文献
26.
Children and their families have been significantly impacted by the unfolding of the COVID-19 syndemic. We sought to identify (1) groups of families with distinct profiles of joint trajectories of parental anxiety and child emotional distress and (2) protective and risk factors associated with these dual-trajectory profiles. A sample of 488 parents (65% White; 77% mothers) with 3- to 8-year-old children (MAge = 5.04, SDAge = 1.59) was followed from late March to early July in 2020. Survey data on parent (i.e., anxiety symptoms) and child (i.e., emotional distress) adjustment were collected at three time points. Using multivariate growth mixture modeling, we identified one group with low parental anxiety and child emotional distress (42.7%) and three other distinct groups with varying risk levels among parents and/or children. We also identified protective (e.g., positive parenting) and risk (e.g., child negative affect, negative parenting, perceived stress with racism) factors in predicting parent and child adjustment. It can be concluded that, overall, our sample (mostly middle- and high-socioeconomic status families) demonstrated family resilience amid COVID-19, consistent with prior disaster coping literature. At the same time, our findings also indicated the need to identify at-risk families and modifiable factors for post-disaster public health interventions. 相似文献
27.
Food stealing is often a serious behavioral problem among children with diagnoses of autism and other developmental disorders. Very few empirical studies concerning this behavioral challenge have been reported. We applied a correspondence training procedure to teach self-control as replacement behavior to four children with autism and developmental disorders who displayed food stealing in the community. A changing criterion design embedded within a nonconcurrent multiple-probe across participants design was used. The treatment succeeded for all four participants by increasing latency to eating highly preferred food to a predetermined criterion and reducing occurrences of food stealing to zero. Three participants generalized the replacement behavior to natural settings and maintained the behavior for 2 weeks, 1 month, 2 months, 3 months, and 4 months. One participant without expressive language was taught successfully during treatment trials but failed to maintain and generalize the behavior. A functional relation between delaying food eating and Say-Do correspondence training was demonstrated. 相似文献
28.
Erin A. Skinner Brianna Le Busque Jillian Dorrian Carla A. Litchfield 《Journal of Consumer Behaviour》2023,22(5):1096-1111
The social and environmental impacts of the global fashion industry face increasing scrutiny. As such, consumers and brands look towards ‘sustainable fashion’ for low-impact alternatives. Simultaneously, visual social media platforms such as Instagram have become prevalent places for fashion advertising and discourse. To investigate this under-researched area, the current study utilises visual content and social network analysis to explore how sustainable fashion is presented on Instagram, specifically: (a) what visual characteristics are present within sustainable fashion content, and (b) in what broader contexts and communities is discussion of sustainable fashion taking place? Posts included under the hashtag #sustainablefashion (N = 650) were inspected for visual characteristics, including type of clothing, presence of person, post setting, presence of nature, and post format. Most posts were photographs located indoors with no person and no nature-based elements. The hashtags used alongside #sustainablefashion were analysed with Gephi software to establish a social network and community groups of related topics. Network analysis revealed four key community groups: online-promotional, artisan-traditional, eco-ethical, and Malay-online-selling. Secondhand fashion also appeared to be the most prominent sustainable fashion alternative on Instagram. This study is one of the first to investigate the characteristics of user-generated #sustainablefashion content on Instagram. Whilst social media is a burgeoning avenue for research, existing studies primarily investigate how these platforms can be harnessed for advertising, rather than what users themselves are already posting. Implications for brands who use this platform and opportunities for future research are discussed. 相似文献
29.
Shuang Wang Alexander S. English Yue Deng Ye Zi Zhou Emma E. Buchtel 《Social and Personality Psychology Compass》2023,17(12):e12903
In the pandemic era, social media has provided the public with a platform to make their voice heard. One of the most important public opinions online during a pandemic is blame. Blame can lead to stigma towards patients as well as potential patients and decrease social cooperation, which might impede prevention and control measures during epidemics. Thus, studying online blame during the early days of COVID-19 can facilitate the management and control of future pandemics. By analyzing 3791 posts from one of the most popular social media sites in China (Weibo) over the 10 days immediately after COVID-19 was declared to be a communicable disease, we found that there were four main agents blamed online: Individuals, corporations, institutions, and the media. Most of the blame targeted individual agents. We also found that there were regional-cultural differences in the detailed types of blamed individual agents, that is, between rice- and wheat-farming areas in China. After controlling influence of distance from the epicenter of Wuhan, there were still stable differences between regions: people in wheat areas had a higher probability of blaming agentic, harmful individuals, and people in rice areas had a higher probability of blaming individuals with low awareness of social norms for preventive health behavior. Findings have implications for preventing and predicting blame across cultures in future pandemics. 相似文献
30.
初中生学业成就动机量表的编制 总被引:11,自引:1,他引:10
本研究根据我国初中生的实际编制了一套测量初中生学业成就动机的自陈式量表。该量表由外部行为表现和内部心理因素两个分量表构成。行为表现分置表包括主动性、行为策略和坚持性三个子量表,心理因素分量表包括能力、兴趣、目的、知识价值观四个子量表。测题分析和测验分析的结果表明此量表具有较高的信度和效度,能用于鉴别初中生学业成就动机的水平。 相似文献