Does mediator use contribute to the spacing effect for cued recall? Critical tests of the mediator hypothesis

When study is spaced across sessions (versus massed within a single session), final performance is greater after spacing. This spacing effect may have multiple causes, and according to the mediator hypothesis, part of the effect can be explained by the use of mediator-based strategies. This hypothesis proposes that when study is spaced across sessions, rather than massed within a session, more mediators will be generated that are longer lasting and hence more mediators will be available to support criterion recall. In two experiments, participants were randomly assigned to study paired associates using either a spaced or massed schedule. They reported strategy use for each item during study trials and during the final test. Consistent with the mediator hypothesis, participants who had spaced (as compared to massed) practice reported using more mediators on the final test. This use of effective mediators also statistically accounted for some – but not all of – the spacing effect on final performance.     

蝴蝶效应与临床思维——一例多器官衰竭患者诊疗反思

多器官衰竭或多器官功能障碍综合征在临床中尤其是急诊及重症监护室内常见,各种病因所致的疾病进展到一定程度均可导致多器官衰竭。在本案例中,一例老年男性患者,以急性腹泻起病,后短时间内进展为多器官衰竭。通过对该例患者病史总结、病理生理机制的探讨,以及对整个诊疗过程的反思,结合“蝴蝶效应”理论,总结出一种新的临床思维,并探讨“蝴蝶效应”理论在对该例患者的诊断、治疗甚至医患沟通方面所起到的作用,以期通过参考该案例,对以后的临床工作起到一定帮助。     

科学假说在揭示嗅觉奥秘中的作用——解读2004年度诺贝尔医学奖

通过分析2004年诺贝尔医学奖的发现过程,揭示假说对科学研究的指导意义。只有勤观察,多思考,大胆假设,小心求证,才能揭示自然规律。     

视觉工作记忆回溯线索效应的产生机制：认知阶段分离

以往研究关于视觉工作记忆回溯线索效应的产生机制主要存在5种假设,目前依然存在争议。本研究通过改进前人研究实验范式,采用包含内源性回溯线索的颜色回忆报告范式,进一步对这5种假设进行检验。在实验1中,我们调控了线索与探测阵列之间的时间间隔,发现不同时间间隔不影响无线索条件的行为表现,而在正常线索条件中被试的记忆精度以及能记住的项目数量均优于无线索条件;在实验2中,我们对回溯线索伴随的干扰刺激类型进行控制,结果显示,在不同条件下记忆精度不存在差别,但当回溯线索伴随干扰刺激呈现时,被试能记住的项目数量会被降低,降低程度受干扰刺激的类型调制;在实验3中,我们对伴随回溯线索的干扰刺激的呈现时间进行控制,发现虽然回溯线索效应仍然存在,但干扰刺激的呈现时间不会影响效应程度。研究结果表明,回溯线索的出现使得被试能够在决策加工前完成内部注意资源的再分配,从而避免了同时进行这两种认知加工与记忆表征维持本身竞争认知资源。本研究为认知阶段分离假设提供了支持证据,对解决回溯线索效应产生机制的争议以及理解内部注意与视觉工作记忆的关系有重要意义。     

Alcohol intoxication and memory for events: A snapshot of alcohol myopia in a real-world drinking scenario

Alcohol typically has a detrimental impact on memory across a variety of encoding and retrieval conditions (e.g., Mintzer, 2007; Ray & Bates, 2006). No research has addressed alcohol's effect on memory for lengthy and interactive events and little has tested alcohol's effect on free recall. In this study 94 participants were randomly assigned to alcohol, placebo, or control groups and consumed drinks in a bar-lab setting while interacting with a “bartender”. Immediately afterwards all participants freely recalled the bar interaction. Consistent with alcohol myopia theory, intoxicated participants only differed from placebo and control groups when recalling peripheral information. Expanding on the original hypervigilance hypothesis, placebo participants showed more conservative reporting behaviour than the alcohol or control groups by providing more uncertain and “don't know” responses. Thus, alcohol intoxication had confined effects on memory for events, supporting and extending current theories.     

阻塞性睡眠呼吸暂停低通气综合征与舒张性心力衰竭相关性研究进展

阻塞性睡眠呼吸暂停低通气综合征(OSAHS)可诱发舒张性心力衰竭,引起多种临床症状,对患者预后及生活质量产生更多不良影响.其主要病理生理学变化为慢性间歇性或持续性乏氧和高碳酸血症.舒张性心力衰竭发生机制复杂,OSAHS可通过乏氧、神经系统功能改变、炎症反应及水钠潴留而诱发或加重舒张性心力衰竭.OSAHS与舒张性心力衰竭有密切关系,OSAHS可引起并加重心衰,而心衰患者可能会伴发OSAHS,其互为因果,互相促进.在临床治疗方面,我们应充分重视两者相关性及其危害性,制定合理治疗方案.     

重新认识心衰机制中的心脏舒张期耗能

长期以来,对心衰和心衰机制的认识一直存在争议,所以心衰的治疗一直是国内外心血管领域中的一个挑战.为了澄清心衰机制的内涵,本文用弗兰克-斯塔灵定律以及能量守恒定律作为重建心脏理论以及心衰机制的依据,论证了心脏的做功是从动能向势能,又从势能向动能的转换过程.并根据临床事实等来证实心脏舒张是在作功,与收缩期作功是等同的.没有心脏的舒张就没有心脏的收缩,心脏功能下降实际上是舒张与收缩功能同时的下降.不存在有收缩功能正常的舒张功能下降.心功能的判定标准不能采用射血分数,而应该采取能量消耗的定量方法来测定.