Limits of dynamic object perception in pigeons: Dynamic stimulus presentation does not enhance perception and discrimination of complex shape

A go/no-go procedure was used to train pigeons to discriminate pictures of human faces differing only in shape, with either static images or movies of human faces dynamically rotating in depth. On the basis of experimental findings in humans and some earlier studies on three-dimensional object perception in pigeons, we expected dynamic stimulus presentation to support the pigeon’s perception of the complex morphology of a human face. However, the performance of the subjects presented with movies was either worse than (AVI format movies) or did not differ from (uncompressed dynamic presentation) that of the subjects trained with a single or with multiple static images of the faces. Furthermore, generalization tests to other presentation conditions and to novel static views revealed no promoting effect of dynamic training. Except for the subjects trained on multiple static views, performance dropped to chance level with views outside the training range. These results are in contrast to some prior reports from the literature, since they suggest that pigeons, unlike humans, have difficulty using the additional structural information provided by the dynamic presentation and integrating the multiple views into a three-dimensional object.     

The influence of stimulus attributes on duration matching-to-sample in pigeons

A duration matching-to-sample procedure was used to examine the influence of signal properties on temporal estimation and working memory. The results indicated that pigeons responded to durations of a light as if they were longer than equal durations of the absence of the same light, but delay performances did not differ between the two sample types. Similarly, pigeons responded to durations of a bright white light as if they were longer than equal durations of a dim red light, but again, delay performances did not differ between the two sample types. These results are discussed in terms of theoretical issues pertinent to timing, attention, and working memory.     

Young children's knowledge about visual perception: projective size and shape

Although recent research indicates that an increased sensitivity to visual appearances develops around 4 or 5 years of age, evidence from perceptual studies suggests that certain types of appearances, that is, projective size and shape, are not noticed or understood until at least 7. 4 experiments investigated preschool children's knowledge of the projective size--distance and projective shape--orientation relationships. In Experiment 1, 3- and 4-year-olds were asked whether an object should be moved farther or nearer in order to increase or decrease its apparent size. 4-year-olds performed significantly better than chance, but 3-year-olds did not. Experiment 2 showed that 3-year-olds are able to perceive projective size changes, indicating that although they do not fully understand the projective size-distance relationship, the necessary perceptual information is potentially available to them. In Experiment 3, 3- and 4-year-olds were asked to indicate how a circular object should be rotated to make it appear either circular or elliptical. Again, 4-year-olds performed significantly better than chance, but 3-year-olds did not. Again also, the results of Experiment 4 indicate that although 3-year-olds are not aware of the projective shape-orientation relationship, they are capable of attending to changes in projective shape. Thus, the constraints on children's knowledge of the projective size-distance and projective shape-orientation relationships seem to be at least partly cognitive rather than wholly perceptual. These results are interpreted as further evidence for the acquisition of level 2 percept knowledge during early childhood.     

Infant perception of the invariant shape of objects varying in slant.

In a previous study employing habituation-recovery techniques, partial confirmation for shape constancy in 12-week-old infants was found. The infants may have been responding to changes in slant or slant-related cues, leaving unresolved the question of whether shape perception should be considered proximal (retinal) or distal (objective). In the present experiment 12-week-old infants were desensitized to changes in slant prior to test. Following habituation to a shape exposed at varying slants, magnitude of recovery was overwhelmingly greater for a different shape than for the same shape, indicating that the constant real shape of the habituated figure had been perceived across rotational transformations.     

加拿大化运动及其对加拿大高等教育体制的影响

加拿大化运动是20世纪60年代末由加拿大学术界所倡导的学术与文化民族主义运动。从1968年在卡尔顿大学兴起,到70年代意义深远的教育改革和1981年一项新的国家移民政策的制定,加拿大化运动经历了曲折的历程。它对加拿大高等教育的发展,特别是对加拿大大学的课程设置、聘任制度及其实施,以及加拿大民族主义的构建都产生了深远的影响。     

Examining the influence of teacher behavior and curriculum-based movement breaks

Little research has explored the impact of teacher behavior in the relationship between classroom movement breaks and student outcomes. The authors' primary purpose was to explore teacher behavior during classroom movement breaks to determine if teacher behavior served as a moderating variable in the relationship between physical activity and student achievement. The second major aim was to examine these relationships across two different types of movement breaks: (a) academic-content movement breaks and (b) aerobic-based movement breaks. Children (n = 466) in Grades 3–5 from four elementary schools served as participants in the study. Results found that teachers who encouraged students to move and teachers who moved themselves did not necessary have students with higher activity levels during the movement breaks. However, significant differences across the type of movement break provided were found. Implications and limitations are discussed.     

Sex and aggression: the influence of gender label on the perception of aggression in children

To investigate the influence of gender label on adults' perceptions of aggression in children, a videotape of 2 preschool children playing roughly in the snow was shown to 175 college students (139 females, 36 males) who were asked to judge the degree of aggression displayed by 1 of the children (the target child). In the videotape, the children's snowsuits disguised their actual gender, and 4 experimental conditions were created by varying the gender label of both the target and the other (nonrated) child. Hence, the 4 conditions consisted of all possible combinations of gender; boy-boy, boy-girl, girl-boy, and girl-girl. All subjects viewed the same film; only the gender labels used to describe the children varied. Subjects' aggression ratings of the target child varied significantly as a function of the gender label attributed to both the target and the nonrated child. Specifically, the boy-boy condition was rated as significantly less aggressive than the other 3 conditions, which did not differ in level of perceived aggression. This effect was particularly strong among subjects with more experience with children. The results have interesting implications for understanding the process of social category perception.     

The influence of a residential outdoor education programme to pupil’s environmental perception

This empirical study finds support for the hypothesis that participation in a special residential education programme enhances facets of pupils’ environmental perception. A 4-day extra-curricular educational unit with a cognitive outdoors focus (established in a nature centre in France) was surveyed by using a two stage sampling design in a pre-post-treatment evaluation; the post-test was delayed for a one-month period after participation. All selected participating pupils (n=151) responded twice to the same perception questionnaire. The factorial structure of this questionnaire had been previously developed using a large European sample (n=4500) and separately validated in a smaller French pupil sample (n=900). The matched-pair pre-post-test survey showed significant differences in two of the five primary factors; both of them covered utilitarian preferences and scored in a way which indicated an increase in sensitivity to the environment. A pre-post-tested control group (n=78) revealed no significant difference. Possible reasons for the partial shift in primary factors are discussed, including a consideration of two related studies (in Germany and Switzerland) which were both monitored by the same measurement instrument.     

简析李大钊对农民问题的认识

〕中国共产党创始人之一的李大钊很早就注意到了农民问题,他在几篇文章中提出了重要见解,如估量革命动力时,不能不注意农民是其重要成分,只有农民武装才能把帝国主义和军阀所造成的兵匪扰乱之政局扭转过来等。他的观点是我党的宝贵的理论财富     

乡镇初中教师自我公平感知影响与重建——基于承认正义理论的视角

教师自我公平感知影响其教育教学行为,很多时候甚至产生决定性作用.从承认正义理论视角来看,自尊、自重和自信是教师自我公平感知的三个重要维度.以留守儿童为主体的乡镇初中,优秀生源流失,学生学业失败和高辍学率似乎是不可逆的.调查发现,乡镇教育生态恶化与教师自我公平感不佳导致乡镇教师热情枯竭和成就感丧失,而基于尊重环境与制度自信下的教师具有高公平获得感.据此,采取相关举措重建教师的自尊、自重和自信,进而提升教师自我公平感知,提升农村教师队伍的职业动力和专业水平,是破解义务教育“城镇挤、乡镇弱”和控辍保学难题等教育生态恶化现象的一个重要方向.     

乡镇初中教师自我公平感知影响与重建——基于承认正义理论的视角

教师自我公平感知影响其教育教学行为,很多时候甚至产生决定性作用.从承认正义理论视角来看,自尊、自重和自信是教师自我公平感知的三个重要维度.以留守儿童为主体的乡镇初中,优秀生源流失,学生学业失败和高辍学率似乎是不可逆的.调查发现,乡镇教育生态恶化与教师自我公平感不佳导致乡镇教师热情枯竭和成就感丧失,而基于尊重环境与制度自信下的教师具有高公平获得感.据此,采取相关举措重建教师的自尊、自重和自信,进而提升教师自我公平感知,提升农村教师队伍的职业动力和专业水平,是破解义务教育“城镇挤、乡镇弱”和控辍保学难题等教育生态恶化现象的一个重要方向.     

论西方现代诗歌运动对新诗革命的影响

中国的新诗革命是世界现代诗歌运动的一部分,深受西方现代诗歌运动的影响.由于20世纪初的中国正处在政治革命和文化革命的激进时代,西方现代诗歌运动中的自由诗革命得到了中国新诗人的极端重视.19世纪末20世纪初,美、英、法等国的诗的自由化、散文化的诗体解放倾向被中国新诗人故意夸大,助长了新诗诗人对古代汉诗诗体的极端否定,使新诗革命由本应是纯粹的文体革命变味为政治性的文体革命,其破坏性不仅超出了汉语诗歌当时的承受能力,而且影响了新诗初期及以后百年的诗体建设.     

Cross-modal transfer of stimulus control in the albino rat: A stimulus delay procedure

The present experiment demonstrated in a simultaneous discrete trial discrimination that the stimulus control of a rat’s leverpress response can be errorlessly transferred across stimulus modalities, i.e., from light to click location and from click to light location. Subsequent to acquisition of the original discrimination, the original and new discriminative stimuli were simultaneously presented for several sessions. Then the new discriminative stimulus was presented 3 sec prior to the onset of the original discriminative stimulus. Within the direction of transfer, e.g., from light to click location, the delay group emitted fewer trial and intertriai errors than the control group. As the new discriminative stimuli acquired control over responding, the response latency distributions were differentially affected. The results suggest that the transfer of control from the original to the new discriminative stimuli is mediated by the temporal aspects of the delay interval.     

The faculty's perception of the mature adult: A case study

With the rise in numbers of mature adults becoming interested in returning to college, information is needed if programs are to be designed to meet the needs of these students. A critical input into the re-designing of programs is the faculty. This study was undertaken to identify the needs of the mature adults by use of a questionnaire sent to undergraduate faculty asking for their perceptions of mature (ages 25 or older) adult student. Results indicate that there is intense interest in the needs of the mature adult population but that there is little experience with this audience among the faculty. This and other data suggest that there is a need for an orientation program to acquaint the faculty with the mature adult population, and to develop an instructional program to fulfill their needs.