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51.
Two hypotheses were tested about how young children answer questions with the quantifiers all and some: (a) that children use syntactic cues in determining which noun phrase is quantified, and (b) that children evaluate a some-statement as part of evaluating an all-statement. To test these hypotheses, the same group of 60 4- to 7-year-olds were asked four contrasting types of quantitative questions. The results indicated that children can use syntactic cues under some presentation conditions. However, there was no evidence for an asymmetry between the all-and some-questions. A model of how young children might answer quantitative questions was then considered.  相似文献   
52.
Clinical and autopsy studies were made on a right-handed man who had central deafness and subcortical motor aphasia, and the literature on central deafness and on subcortical motor aphasia was analyzed. Central deafness is due to bilateral destruction of the primary auditory cortex. It is sometimes difficult to distinguish from word deafness and from auditory agnosia, which are due to pathology in other parts of the temporal lobes. There is almost always some preserved hearing in central deafness, possibly from some auditory pathway other than the classical pathway. In this patient the subcortical motor aphasia was due to bilateral destruction of the motor cortex for the mouth and throat. In some other cases subcortical motor aphasia was due to the same pathology that usually causes Broca's aphasia; in these cases the unexpected preservation of writing was perhaps related to some difference in how language functions were organized in the brain.  相似文献   
53.
The capacity to selectively attend to only one of multiple, spatially separated, simultaneous sound sources—the “cocktail party” effect—was evaluated in normal subjects and in those with anterior temporal lobectomy using common environmental sounds. A significant deficit in this capacity was observed for those stimuli located on the side of space contralateral to the lobectomy, a finding consistent with the hypothesis that within each anterior temporal lobe is a mechanism that is normally capable of enhancing the perceptual salience of one acoustic stimulus on the opposite side of space, when other sound sources are present on that side. Damage to this mechanism also appears to be associated with a deficit of spatial localization for sounds contralateral to the lesion.  相似文献   
54.
Performance maintained under concurrent schedules consisting of a variable-interval avoidance component and a variable-interval positive-reinforcement component was studied in three human subjects using points exchangeable for money as the reinforcer. The rate of responding in the avoidance component increased, and the rate of responding in the positive-reinforcement component declined, as a function of the frequency of point-losses avoided in the avoidance component. The performance of all three subjects conformed to equations proposed by Herrnstein to describe behavior in concurrent schedules. The logarithms of the ratios of the response rates in the two components, and the logarithms of the ratios of the times spent in the two components, were linearly related to the logarithms of the ratios of the frequency of loss avoidance in the avoidance component to the frequency of reinforcement in the positive-reinforcement component. When a changeover delay of 5.0 sec was imposed, the slopes of the linear functions were close to 1.0 in the case of two subjects, whereas the third subject exhibited significant undermatching. For two subjects the changeover delay was then reduced to 2.0 sec; in both cases the slopes of the linear functions were lower than under the 5.0-sec condition. One subject participated in a third phase, in which no changeover delay was imposed; there was a further reduction in the slopes of the linear functions.  相似文献   
55.
56.
The current study investigates two recently identified threats to the construct validity of behavioral inhibition as a core deficit of attention-deficit/hyperactivity disorder (ADHD) based on the stop-signal task: calculation of mean reaction time from go-trials presented adjacent to intermittent stop-trials, and non-reporting of the stop-signal delay metric. Children with ADHD (n = 12) and typically developing (TD) children (n = 11) were administered the standard stop-signal task and three variant stop-signal conditions. These included a no-tone condition administered without the presentation of an auditory tone; an ignore-tone condition that presented a neutral (i.e., not associated with stopping) auditory tone; and a second ignore-tone condition that presented a neutral auditory tone after the tone had been previously paired with stopping. Children with ADHD exhibited significantly slower and more variable reaction times to go-stimuli, and slower stop-signal reaction times relative to TD controls. Stop-signal delay was not significantly different between groups, and both groups’ go-trial reaction times slowed following meaningful tones. Collectively, these findings corroborate recent meta-analyses and indicate that previous findings of stop-signal performance deficits in ADHD reflect slower and more variable responding to visually presented stimuli and concurrent processing of a second stimulus, rather than deficits of motor behavioral inhibition.  相似文献   
57.
实际应用中测验往往具有多维结构, 如果仍采用单维IRT方法进行等值, 会得到不准确的结果。因此对于多维结构的测验, 需要使用多维IRT等值方法来实现参数的转换。基于共同题设计, 文章通过模拟研究的方法, 考察了不同铆测验设计下几种多维IRT等值方法的表现, 同时考虑了测验长度、两个维度题目数量的比例、铆测验长度、铆测验的选择策略、两个维度之间的相关和等值群体的能力水平差异六个因素的影响。所比较的多维IRT等值方法有:均值/均值(MM)方法, 均值/标准差(MS)方法, Stoking-Lord (SL)方法, Haebara (HB)方法, 最小平方(LS)方法。结果显示:(1) SL, HB和LS方法得到的等值误差均方根最小, 且在各条件下表现较为稳定。(2) MM和MS方法在非等组条件下呈现出很大的误差均方根。(3)铆测验设计对SL, HB和LS方法的等值结果没有显著影响。(4)在两个维度之间的相关较高, 测验长度和铆测验长度较长, 等值群体的能力水平没有差异的条件下, SL, HB和LS方法得到的等值误差均方根最小。  相似文献   
58.
工作投入研究的现状   总被引:15,自引:0,他引:15  
工作投入指的是一种与工作相关的积极、完满的情绪与认知状态,具有持久性和弥散性的特点。工作投入对个体的工作绩效和某些工作态度及行为变量,以及顾客满意度、生产力、利润率和单位总体绩效等组织结果变量均具有一定的影响。工作投入的影响因素包括个体特征因素、与工作相关的因素以及与家庭相关的因素等3个方面。文章在对工作投入的相关研究进行全面述评的基础上,指出未来的研究有必要进一步加强对工作投入的干预机制等五方面问题的探讨  相似文献   
59.
注意缺陷多动障碍(ADHD)的发病群体多为5岁以后的儿童,主要临床表现是多动、冲动,注意力无法集中,对一项任务不能够有规划进行下去,而且脾气暴躁、易怒。近年来,心理学界、神经科学界和教育学界等对ADHD的研究取得了很多进展。本文概括性地介绍了ADHD病症的基本特征,目前对于患者脑机制损害的研究,并从药理学和行为学等方面讨论了ADHD的治疗方法和手段。  相似文献   
60.
图形项目记忆与位置来源提取的ERP研究   总被引:1,自引:0,他引:1  
采用事件相关电位(ERP)方法研究大学生图形项目记忆与位置来源提取新/旧效应的时、空分布特征。学习屏幕左侧(或右侧)呈现的图形后在屏幕中央呈现某一测验项目(已学图形或新图形),对受试者进行两类测验:其一是判断该项目是否已学过;其二是将从某侧学过的测验项目判断为目标,而将其它测验项目判断为非目标的来源测验(排除任务)。实验结果表明:图形位置来源提取比项目再认新/旧效应的头皮分布更广,持续时程更长;与前人相同实验范式的研究结果相比,本研究位置来源提取效应的头皮分布范围较广;非目标-旧图形与目标图形新/旧效应的头皮激活程度不同。上述结果说明:图形位置来源提取比项目再认激活的大脑区域更多,这与双重加工模型的观点一致;实验范式和来源知觉的特性共同调节来源记忆新/旧效应的时、空分布特征;意识水平对来源信息提取的新/旧效应存在一定的影响  相似文献   
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