一种对动物学习记忆能力突变筛查的新途

本文详细描述了一种全自动化的行为检测方案。在自然饲养环境/检测环境(24/7)中, 我们测量了小鼠针对两个给食器中获得食物的比例与它们在相应给食器停留时长的比例进行匹配的精确性与准确性。该方案是对传统条件性习得 (trials-to-acquisition) 行为测验设备的改进, 可以检测动物时间间隔能力的精确性与准确性, 对定时目标选择的相关概率的效果, 以及记忆一天中从不同给食器中获得食物次数的精确性与准确性。该压缩系统避免了在整个实验过程中对小鼠的持握操作, 可忽略实验者/技术员的实验操作时间, 而且可以递送小鼠置入实验环境后, 7~9个实验日中全部3组实验流程产生的大量结果。其中, 第一个实验流程为单个24小时周期内完成的时间匹配能力的筛查, 它对动物的时间、空间估计能力的记忆机制进行精确检测。因此, 该系统允许在有限的实验空间、较短的实验周期内, 对大量的实验小鼠进行有可能存在的学习记忆能力缺陷进行大规模筛查。此外, 该系统运行所依赖的软件可以在公共开放平台获得。     

Representation of memory for order of mental operations in cognitive tasks

Recent research shows that people learning a cognitive task acquire a memory for the order of operations applied, independent of the data to which those operations were applied. We designed two experiments to show how this sequence memory is represented. Experiment 1 compared predictions based on 3 possible sequence representation methods: composition, dyad transition, and associative chain. Latency and error results from a simple sequential task supported the associative chain representation. The associative links between operations presumably enhance performance by priming subsequent operations but do not operate in an all-or-none fashion. Experiment 2 explored whether transfer items that matched the first 2 rules and first 3 elements of a training item could bias participants toward executing a composed production learned during training. Latency and undetected error results were consistent with an associative chain representation but not with additional predictions made by the composition representation. These two experiments support the representation of operation sequences in memory as an associative chain.     

Talking about the silent fear: adolescents' experiences of violence in an urban high-rise community

The self-reported violent experiences of adolescents living in a public-subsidized urban high-rise building were examined. This effort was part of an interdisciplinary, community-university collaboration program called the HOME (High-rise On-site Multifamily Environments) Family Support Project. A survey of violent experiences and a one-on-one structured interview were conducted with 20 adolescent residents. Results of the quantitative and qualitative analyses revealed high degrees of exposure to violence among these adolescents, concerns for their personal safety, as well as insights into what they believe adults could and should be doing to address increasing levels of community violence. The implications of these results for conducting ecologically valid research on sensitive issues with adolescents and for family support program planning are discussed.