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1.
Rats trained to push a joystick to the left or right for food reward were given two successive tests in which neither response was reinforced. Prior to Test 1, subjects were either confined in the apparatus with a passive conspecific (Group None), or allowed to observe a conspecific demonstrator making 50 nonreinforced responses in the direction that had beeirrewarded during observer training (Group Same) or in the opposite direction (Group Different). In Test 1, Group Same made fewer previously reinforced responses than did Group Different, which made fewer than Group None, and Groups Same and Different each made fewer previously nonreinforced responses than did Group None. In Test 2, Group Same made fewer previously reinforced responses than did Group None. These results indicate that observation of nonreinforced responding can reduce resistance to extinction (Test 1) and spontaneous recovery (Test 2) in rats. 相似文献
2.
Rats acquired a serial alternation task in an eight-arm radial maze that was partitioned into four pairs of arms. Each pair was associated with a different distal stimulus. Rats were initially forced to the left or right arm in each pair (the study segment) before being exposed to both arms in each pair (the free-choice or test segment). Only the previously blocked arm of each pair remained baited. Following initial training, proactive interference (PI) was induced by presenting rats with a forced-choice (prestudy) segment containing arm positions opposite those in the subsequent study segment. Such trials generated poorer free-choice accuracy than did trials without a prestudy segment. Forcing rats to both arms in the pair in a prestudy segment produced only transient PI. A slight improvement in rats’ free-choice performance was obtained by forcing them to the same arm position, but only when the test segment was delayed by 30 min. Increasing the interval between the prestudy and study segments from 2 to 30 min eliminated PI, but only when free-choice testing was delayed by 2 min rather than by 30 min. These results suggest that intratrial PI in this preparation was primarily due to confusion about which arm position in each pair had been visited during the last forced-choice segment. 相似文献
3.
Patrick Anselme 《Learning & behavior》2018,46(3):294-305
Terrestrial isopods (or woodlice), like the members of the other arthropod taxa, have a sophisticated nervous system that makes them sensitive to specific environmental factors. They can search for survival-related opportunities (e.g., approaching food sources or avoiding sunny areas). Two experiments examined how rotational stress could influence the propensity of common woodlice, Porcellio scaber to exhibit survival-related behaviors such as traveling and rearing up in a hostile environment. Experiment 1 assessed the behaviors of stressed and nonstressed woodlice exposed to a familiar or a novel environment without rewards. Experiment 2 assessed the effects of stress in woodlice given a free choice between a familiar and a novel environment without rewards. In the nonstressed individuals, the results showed a decrease in locomotor activity (habituation) and an increase in the time spent rearing up (sensitization) on the arena’s walls over time. In the stressed individuals, repeated rotation had a detrimental effect on the time spent rearing up, but locomotion was decreased only in the stressed individuals that were not preexposed to the test environment beforehand. In addition, immobilization periods—as a plausible indicator of stress—were longer in the absence of preexposure. It is suggested that preexposure had some antistress protective effects on habituated but not on sensitized, exploratory behaviors in woodlice. 相似文献
4.
Spontaneous alternating behavior (SAB), the tendency of an organism to successively turn left and right in a maze, is a standard
metric of short-term memory in developmental and pyschopharmacological studies. Although SAB is perhaps the most phylogenetically
widespread behavior in motile lifeforms, conflicting data on SAB exist for several sets of closely related taxa. For example,
previous studies provide contradictory evidence concerning the existence of spontaneous alternation behavior in the protozoanParamecium. However, these studies tested different species, using very different experimental designs. Using a single, factorial design
for both previously tested species,P. multimicronucleatum andP. caudatum, we found that, in fact, the two species do not differ in their alternation behavior; specifically, they alternate in mazes
with short tracks, but not in mazes with long tracks. These results are in accord with alternation studies on other taxa,
and they fully resolve the apparent contradictions in the earlier studies onParamecium. They also indicate that caution should be used in interpreting variable results across species tested with different experimental
designs and suggest that, in at least some taxa, SAB may not be strictly dependent on the use of short-term memory. 相似文献
5.
Emily C. Merz Elaine A. Maskus Samantha A. Melvin Xiaofu He Kimberly G. Noble 《Child development》2020,91(3):846-860
The mechanisms underlying socioeconomic disparities in children's reading skills are not well understood. This study examined associations among socioeconomic background, home linguistic input, brain structure, and reading skills in 5-to-9-year-old children (N = 94). Naturalistic home audio recordings and high-resolution, T1-weighted MRI scans were acquired. Children who experienced more adult–child conversational turns or adult words had greater left perisylvian cortical surface area. Language input mediated the association between parental education and left perisylvian cortical surface area. Language input was indirectly associated with children's reading skills via left perisylvian surface area. Left perisylvian surface area mediated the association between parental education and children's reading skills. Language experience may thus partially explain socioeconomic disparities in language-supporting brain structure and in turn reading skills. 相似文献
6.
孙占林 《黄石理工学院学报(人文社科版)》2010,27(2):27-31
古人自然方位尊卑的主要特征是崇阳。在君位之下,现实世界的朝堂礼仪场景以东为尊;神灵世界和室内场景以西为尊;在面位过滤的作用下,自然方位的阴阳因素投射是形成左右尊卑的基础因素,自身位的性质是影响左右尊卑意义演变的重要因素。 相似文献
7.
Rats were tested for spontaneous alternation in a variety of mazes differing in the angle between choice alleys. Uniformly high alternation rates were found at all angles from 330 down to 90 deg. At 45 or 0 deg, the rates approximated a chance 50%, and at angles between 45 and 90 deg the alternation rates were also intermediate. The hypothesis that the spatial distance between goal regions is the critical factor was rejected, and it was concluded that the angle between alleys is the principal factor determining alternation under these conditions. The results support the idea that alternation in the rat is basically a vestibular phenomenon. 相似文献
8.
Twenty male Mongolian gerbils (Meriones unguiculatus) were tested for spontaneous alternation behavior in a T-maze under five cue conditions: (1) all cues present, (2) only S’s own odor trail, (3) only orientation cues, (4) no cues, (5) only another S’s odor trail. Significant alternation was found only in the first two conditions, indicating that odor trail is the only alternation cue for gerbils under testing conditions which also yield considerable orientation alternation in rats. There was also a tendency for gerbils to “alternate” the odor trail left by the noncagemate, but to follow that of a cagemate. A previous failure to find evidence of alternation in gerbils may have been due to a lack of opportunity for the animals to engage in trail-marking behavior. 相似文献
9.
孙占林 《黄石理工学院学报(人文社科版)》2010,27(1):28-32,41
古人自然方位尊卑的主要特征是崇阳。在君位之下,现实世界的朝堂礼仪场景以东为尊;神灵世界和室内场景以西为尊;在面位过滤的作用下,自然方位的阴阳因素投射是形成左右尊卑的基础因素,自身位的性质是影响左右尊卑意义演变的重要因素。 相似文献
10.
The current four experiments investigated gaze following behavior in response to gaze and head turns in 4-month-olds and how reinforcement learning influences this behavior (N = 99). Using interactive eye tracking, infants’ gaze elicited an animation whenever infants followed a person’s head or gaze orientation (Experiment 1.1, 2.1 and 2.2) or looked at the opposite side (Experiment 1.2). Infants spontaneously followed the direction of a turning head with and without simultaneously shifted gaze direction (Cohen’s d: 0.93–1.05) but not the direction of isolated gaze shifts. We only found a weak effect of reinforcement on gaze following in one of the four experiments. Results will be discussed with regard to the impact of reinforcement on the maintenance of already existing gaze following behavior. 相似文献
11.
三分螺旋折流板换热器壳侧通道二次流分析 总被引：1，自引：0，他引：1
采用数值模拟方法分析了35°倾斜角三分螺旋折流板换热器壳侧流体流动特性,重点考察了壳侧通道的二次流分布.在子午切面上的结果表明：壳侧通道内轴心区域的流体受螺旋流动离心力的作用存在向外扩张的趋势,而外围区域的流体在向心力的作用下存在向轴心流动的趋势;在壳侧通道的每个螺旋周期内,流线分成上下2股,并在左侧折流板附近形成迪恩涡,在右侧折流板附近开始向心流动并最终被吸进轴向主流中.一个螺旋周期内平行的2块折流板之间多个平行切片的结果进一步证实了二次流的存在,同时还显示了V形缺口处存在的倒流现象.二次流有利于螺旋通道内流体的掺混,有效促进主流流体与近壁流体的动量和质量交换,从而可强化此类换热器的传热. 相似文献
12.
本文介绍了柯西中值定理的多种证明方法及其应用.其中证明方法有:利用构造辅助函数,根据罗尔定理证明;利用坐标旋转变换证明;利用达布定理证明;利用复合函数证明;利用同增量性证明.其应用方面为:求极限;证明不等式;证明等式;证明单调性. 相似文献
13.
14.
提出中国社会主义市场经济在新的成长期呈现出的新特点是 :成长的环境从优惠、无序转向公平、有序 ,成长的要素从资本主导转向技术主导 ,成长的内容从总量扩张转向结构优化升级 ,成长的空间从农村转向城市 ,成长的动力从政府推动转向WTO推动 相似文献
15.
When learning to program in Logo, many young children experience difficulties using the right and left turn commands. This paper looks at the spatial concepts required for the understanding and manipulation of these commands. We begin by providing an overview of research on children's Logo learning and point to specific problems children have with right and left commands and to related characteristics of standard Logo systems that seem to contribute to these problems. To shed further light on the source of these problems, the psychological-cognitive literature on the development of spatial concepts concerned with the use of frames of reference and obliques is reviewed. It is argued that in order for children to handle meaningful programming projects they need to master a set of prerequisite skills. These skills, involving the development of elaborated and explicated spatial concepts, include a distinction between right and left, the intentional reference to the Turtle as a frame of reference, the assignment of appropriate axes and the application of units of measurement for determining distance and angles. We conclude by suggesting that children need to be exposed to Logo programs designed to facilitate the development of spatial concepts which would enable the successful progression to more complex Turtle Geometry programming tasks. 相似文献
16.
Gordon and his associates (e.g., Gordon & Feldman, 1978,Learning and Motivation,9, 164–178; Feldman & Gordon, 1979,Learning and Motivation,10, 198–210; Gordon, Taylor, & Mower, 1981,American Journal of Psychology,94, 309–322) have reported that a reactivation treatment significantly enhances memory for prior forcings in delayed alternation using rats. The reactivation treatment consisted of placing the rat in the goal arm to which it had been forced previously on that trial. The confinement occurred in the absence of food and was 5 sec in duration. The present experiments explored the possibility that the treatment might influence performance by affording an opportunity for new information to be acquired during the confinement period. Evidence consistent with this view was found in that (1) accuracy was reduced on trials in which the initial event was a 5-sec confinement to the arm opposite that of the target forcing and (2) increasing the duration of the confinement from 5 to 15 to 45 sec increased the magnitude of this effect. It was concluded that the effectiveness of goal-arm confinement as a reactivation treatment does not necessarily implicate processes of retrieval in delayed alternation behavior. 相似文献
17.
基于手机平台,借助于蓝牙技术,设计和实现了一种无线遥控小车新的解决方案。设计以手机控制平台、蓝牙通讯模块、电机驱动模块等硬件模块组成的遥控小车。实现小车的前进、后退、前左转弯、前右转弯、后左转弯、后右转弯等实时控制功能。为遥控玩具小车的设计提出了一种新的思路,同时可以为将来智能家居的遥控设计提供一定的参考意义。 相似文献
18.
话语的机构性权力:电视访谈中的话轮转换 总被引：1，自引：0，他引：1
李慧锋 《北京工业职业技术学院学报》2006,5(4):49-52
话轮(turn)是人们日常会话的基本结构单位,包括说话轮次的长短,顺序,内容变化等.以H.Sacks等人提出的话轮转换规则为理论基础,通过对电视访谈的分析,对话轮转换规则进行探讨.结果表明,话轮转换规则不仅在日常会话中起作用,在电视访谈中也同样起作用.但电视访谈中的话轮转换与一般日常会话又有所不同,主要体现在谈话双方的发话权和对话轮控制权的不对等上. 相似文献
19.
赵永进 《商丘职业技术学院学报》2003,2(2):44-46
清末新政时期的地方官制改革是其政治体制改革的重要组成部分。其各项政策的出台是由世界立宪潮流趋向力、封建皇权专制导向力、地方官吏之背向的反作用力、社会舆论的意向力、新政之指向力等诸因素推动而成的。 相似文献
20.
To study sensitivity to radial location of an odor source, 20 human newborns, ranging from 16 to 130 hours of age, were presented with a small amount of ammonium hydroxide. The odor source was placed near the nose slightly to the left or right of midline, with its position randomized over repeated trails. Direction of headturn with respect to the odor location and diffuse motor activity were scored from the videotape recordings of the newborns' behavior. It was found that as a group, the newborns turned away from the odor source more frequently than they turned toward it. The tendency to turn away from the odor was stronger in infants who displayed less motor activity after the response. Newborns also exhibited a right bias in the direction of the head movements. It is concluded that a spatially appropriate avoidance response is present in the neonate and that the newborn is innately sensitive to the radial location of an odor. 相似文献