The cholinergic neurotransmitter system in human memory and dementia: A review

The present paper reviews three types of evidence implicating the role of acetylcholine in human memory and dementia: (1) neuropathological evidence that the cholinergic transmitter system is depleted in Alzheimer-type dementia; (2) psychopharmacological studies that have employed “cholinergic blockade” as a model of cholinergic depletion; and (3) clinical studies of cholinergic “replacement” therapy in Alzheimer-type dementia. The evidence that the cholinergic system is depleted in Alzheimer-type dementia has been complemented by the finding that cholinergic blockade in healthy subjects causes a substantial learning (or “acquisition”) deficit in episodic memory. The overall results of studies of replacement therapy have generally been disappointing, but a few have reported benefits in recall and recognition tests. The role of the cholinergic system in many aspects of memory remains to be elucidated; but it seems unlikely that cholinergic depletion accounts for all aspects of the memory disorder in Alzheimer-type dementia, and possibly the depletions of other neurotransmitters also contribute to the memory impairment.     

Retrograde amnesia in patients with hippocampal, medial temporal, temporal lobe, or frontal pathology

There is considerable controversy concerning the theoretical basis of retrograde amnesia (R.A.). In the present paper, we compare medial temporal, medial plus lateral temporal, and frontal lesion patients on a new autobiographical memory task and measures of the more semantic aspects of memory (famous faces and news events). Only those patients with damage extending beyond the medial temporal cortex into the lateral temporal regions showed severe impairment on free recall remote memory tasks, and this held for both the autobiographical and the more semantic memory tests. However, on t-test analysis, the medial temporal group was impaired in retrieving recent autobiographical memories. Within the medial temporal group, those patients who had combined hippocampal and parahippocampal atrophy (H+) on quantified MRI performed somewhat worse on the semantic tasks than those with atrophy confined to the hippocampi (H-), but scores were very similar on autobiographical episodic recall. Correlational analyses with regional MRI volumes showed that lateral temporal volume was correlated significantly with performance on all three retrograde amnesia tests. The findings are discussed in terms of consolidation, reconsolidation, and multiple trace theory: We suggest that a widely distributed network of regions underlies the retrieval of past memories, and that the extent of lateral temporal damage appears to be critical to the emergence of a severe remote memory impairment.     

Narcissism as a moderator of the relationship between job characteristics and job reactions

A growing body of research has begun to examine the relationship between narcissism and human behavior in organizations. The research to date, however, has been anecdotal and impressionistic. The present research represents the first attempt to use a questionnaire methodology to examine systematically narcissism as an individual difference variable within an organizational context. Using an interactionist perspective, it is posited that narcissism will moderate the relationship between perceived role and job characteristics and work satisfaction. Data are analyzed from a convenience sample of 272 persons who worked full time and who attended college, using subgroup analysis and moderated multiple regression. Only modest evidence of the predicted moderator effects was found. Explanations for the weak results are offered and three possible modifications for future research are recommended.     

主观声旁家族对汉语儿童汉字命名的影响

研究选取三年级、五年级和七年级学生,采用两个汉字命名实验,考察主观声旁家族对汉字命名的影响。实验一操纵主观声旁家族大小,发现三年级儿童没有表现出家族效应;五年级儿童表现出边缘显著的家族抑制效应,即对大家族的字命名更慢;七年级儿童表现出显著的家族抑制效应。实验二操纵了目标字是否有高频家族成员字（higher frequency neighbors,HFNs）这个变量,发现儿童普遍都表现出HFNs抑制效应,即对有高频家族成员字的目标字命名更慢。以上结果表明随着年级增长,主观声旁家族对儿童命名的影响逐渐增强,且高年级儿童已表现出家族抑制效应,这一表现与普遍出现的HFNs抑制效应有关。     

儿童严重脓毒症的认识现状

儿童严重脓毒症是危重病医学所面临的主要课题及难题.脓毒症发病机制复杂,危及全身各个系统、器官,治疗比较困难,尽管有药物治疗、脏器支持等治疗方法,脓毒症致儿童病死率仍居高不下.近年来,连续性血液净化广泛应用于脓毒症、全身炎症反应综合征及多器官功能障碍综合征的治疗并取得较好疗效,血液净化被视为严重脓毒症的一种有效治疗手段.     

遗忘的药物——呋喃妥因在尿路感染中的应用

随着抗生素的不断发明和应用,目前临床中已经发生很多耐药菌的尿路感染,极大地增加了医疗负担。呋喃妥因虽已使用50多年,但很少耐药菌株,费用低廉,临床仍有广阔的应用前景。本文复习呋喃妥因的相关指南推荐、作用机制、体内代谢、临床抗菌特点和副作用等,希望引起对这个被临床逐渐遗忘的药物重视。     

汉字字形关联对错误记忆的影响

采用DRM范式,研究汉字字形关联对错误记忆的影响。实验以占汉字主体的形声字为材料。学习阶段使用了两类字表:在一半字表中,各字表内汉字及相应的关键诱饵具有相同形旁;另一半字表中,各字表内汉字及相应关键诱饵具有相同声旁。再认测试中,被试对两类关键诱饵均表现出了明显的错误记忆,并且其效应大小与字表汉字相似度成正比。这些结果说明,汉字的字形关联可以诱发错误记忆现象,并且这种错误记忆效应由汉字间字形相似度决定。     

发展性阅读障碍书写加工缺陷及其神经机制

发展性阅读障碍是学习障碍的主要类型之一, 严重影响个体认知、情感与社会适应性的发展。书写与阅读关系密切, 阅读障碍者常常表现出书写加工缺陷。在行为层面, 阅读障碍者书写缺陷表现在书写质量差、速度慢和停顿多等多个方面。在脑机制层面, 脑成像研究发现, 阅读障碍者书写加工缺陷与字形加工脑区活动, 以及字形与运动区脑功能与结构连接异常有关。总体而言, 阅读障碍者书写过程中的字形通达缺陷的证据比较充分, 但字形与运动编码的衔接以及运动执行是否存在困难, 尚缺乏研究证据。相对于字母语言, 书写与阅读的关系在汉语中更为紧密, 汉语阅读障碍的书写研究将为开发汉语特色的诊治方案提供重要指导。