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851.
852.
Previous research had indicated positive and significantly higher self-perceptions for disadvantaged children in comparison to advantaged children in grades four through eight. The intention of this research was to determine whether disadvantaged children maintain their more positive self-images when they enter the more integrated environment with advantaged children. It was discovered that both disadvantaged and advantaged high school students had significantly lower self-perception scores than did the elementary school pupils. The importance of the study is in the continued non-support of the hypothesis that disadvantaged children of all ages have negative self concepts—whether in segregated or integrated situations. However, the study further shows that high school students' self-images are not as high as those of younger children—whether they are disadvantaged or advantaged.  相似文献   
853.
    
We used administrative data to examine predictors of medically documented suicide ideation (SI) among Regular Army soldiers from 2006 through 2009 (N = 10,466 ideators, 124,959 control person‐months). Enlisted ideators (97.8% of all cases) were more likely than controls to be female, younger, older when entering service, less educated, never or previously deployed, and have a recent mental health diagnosis. Officer ideators were more likely than controls to be female, younger, younger when entering service, never married, and have a recent mental health diagnosis. Risk among enlisted soldiers peaked in the second month of service and declined steadily, whereas risk among officers remained relatively stable over time. Risk of SI is highest among enlisted soldiers early in Army service, females, and those with a recent mental health diagnosis.  相似文献   
854.
    
Despite well-documented post-adoption needs of adoptive families, most states provide no or very limited post-adoption services. This study describes Right Turn® (RT), a state-wide program for strengthening adoptive families and preventing adoption dissolution. Results suggest: (a) RT is serving its targeted audience of adoptive families with challenging problems indicated by older adopted children with a history of multiple placements, extended time in social services systems, and a host of mental health challenges; and (b) adoption training, family support when navigating access to post-adoption services, and collaboration with adoption-competent therapists appeared to have helped improve program outcomes.  相似文献   
855.
    
Superior visual search is one of the most common findings in the autism spectrum disorder (ASD) literature. Here, we ascertain how generalizable these findings are across task and participant characteristics, in light of recent replication failures. We tested 106 3‐year‐old children at familial risk for ASD, a sample that presents high ASD and ADHD symptoms, and 25 control participants, in three multi‐target search conditions: easy exemplar search (look for cats amongst artefacts), difficult exemplar search (look for dogs amongst chairs/tables perceptually similar to dogs), and categorical search (look for animals amongst artefacts). Performance was related to dimensional measures of ASD and ADHD, in agreement with current research domain criteria (RDoC). We found that ASD symptom severity did not associate with enhanced performance in search, but did associate with poorer categorical search in particular, consistent with literature describing impairments in categorical knowledge in ASD. Furthermore, ASD and ADHD symptoms were both associated with more disorganized search paths across all conditions. Thus, ASD traits do not always convey an advantage in visual search; on the contrary, ASD traits may be associated with difficulties in search depending upon the nature of the stimuli (e.g., exemplar vs. categorical search) and the presence of co‐occurring symptoms.  相似文献   
856.
当刺激图形为高速运动的方波光栅时,可观测到一种新的奇次谐波现象。当被试光栅为某些临界时间频率时,奇次谐波光栅静止不动,稍微偏离这些临界值,谐波光栅开始运动,其表现运动方向,或者与被试光栅相同,或者相反,这取决于被试光栅的时间频率高于或低于临界频率。本文使用视觉时空采样假设和付氏分析,初步解释了这一现象。  相似文献   
857.
本实验是以异色亮度匹配方法,探索视觉系统对在明视觉水平上的低频、不同时间调制的单色光和白光的亮度感觉特性。结果发现,闪光刺激在临界频率以上作用于视觉系统所产生的亮度感觉是遵循塔耳玻特-普拉托定律。而对在临界频率以下亮暗比为4/1的间断单色光刺激所需的周期平均亮度低于恒定单色光所需的亮度幅度,这表明塔耳玻特(Talbort)定律不适用于低频、高亮暗比的间断单色光。仅适用于间断单色光刺激的亮暗比低于1,波长为650纳米的间断单色光。  相似文献   
858.
为研究同时颜色对比机制的空间特性,本实验用光学投影方法产生出不同空间频率的同时颜色对比光栅。实验结果表明,同时颜色对比机制具有低通空间频率反应特性,即随空间频率下降,颜色对比效应增强。这一结果可能为同时颜色对比机制参与图形探测的推论提供一个实验支持。实验中也测试了几种不同条件下人眼对比敏感度函数。  相似文献   
859.
林国彬  龚文合 《心理学报》1992,25(2):95-100
本实验训练恒河猴对两组其和不超过8的刺激实体(卡片上的黑色圆点)进行相加,再与第三组刺激实体进行数多少的比较判断。实验共有9个训练程序,课题逐次由易到难,刺激的数目也由少到多。有一只恒河猴达到了全部9个程序的训练标准。证明恒河猴的确具有学会把两个数进行相加的能力。这种相加不可能是数数的结果,极可能是在知觉上将它们融合或接合在一起。  相似文献   
860.
胡超群 《心理学报》1986,19(1):60-64
本文通过对两例由大脑损伤引起不同阅读障碍的个案分析研究,作出两点推论:第一、阅读理解过程经历着两个不同层级的信息加工处理阶段:(1)字词层级的认知—掌握字词的形、音、义及其连系,(2)语句层级的阅读理解——语句的句法分析,掌握语句的意义;第二、语句层级的理解是一个更起作用、更积极的能动过程。  相似文献   
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