以兔抗鼠淋巴细胞血清为非条件刺激的条件性免疫抑制

采用一种生物类免疫抑制剂-兔抗鼠淋巴血清（rabbit anti-rat lymphocyte serum,ALS）为非条件刺激（UCS）,糖精水为条件刺激（CS）,以双瓶给水法置于鼠笼前端饮用偏好侧。在一次性CS-UCS结合训练后,单独再次给予CS,使卵清蛋白（OVA）免疫过的大鼠表现出脾淋巴细胞对有丝分裂原PWM的增殖反应降低,血抗OVA抗体的总量及脾内抗OVA抗体生成细胞的减少,但动物未表现出条件性味觉厌恶的行为反应。这些结果表明条件性免疫抑制与味觉厌恶行为条件反射没有必然联系,并非是厌恶行为反应或情绪应激的伴随产物。UCS也并非必需具有感觉的毒副作用,条件性免疫抑制是脑高级神经活动调节免疫功能的结果。     

辨别任务中线索有效性对儿童返回抑制发展的影响

采用辨别任务范式,运用三个3×3×3的混合实验设计(线索有效性、年级、靶子出现位置),考察了3种线索-靶子时间间隔下线索有效性对辨别任务中儿童返回抑制发展的影响。结果表明:(1)随着年龄的增长,儿童完成任务所需的反应时逐渐缩短;(2)随着年龄的增长,儿童出现返回抑制所需的SOA缩短;(3)辨别任务的难度比较大,所需的认知技能和工作记忆更多,因此返回抑制出现的机制也就更复杂,线索有效性对辨别任务下的返回抑制的影响并没有呈现出规律性的变化。     

目标与非目标数量变化对多目标追踪的选择性抑制效应

采用多目标追踪和点探测刺激觉察任务相结合的实验范式,考察目标和非目标数量变化对多目标追踪的选择性抑制效应。实验一设置非目标恒定而变化目标数量,结果发现：随着目标数量的增加,目标与非目标间的抑制差异量不随目标数量变化而变化。实验二设置目标恒定而变化非目标数量,结果发现：在非目标数量变化的三种水平下,目标与非目标间的抑制差异量也无显著差异。综合实验结果表明：在多目标追踪的追踪容量或抑制容量范围内,抑制差异量对目标数量或非目标数量变化是不敏感的;注意资源分配方式在一定范围内保持相对稳定。     

冲动性对吗啡诱导的条件性位置偏爱及行为敏感化的影响

许多研究显示, 冲动性与尼古丁、可卡因、海洛因等药物成瘾显著相关, 但它对吗啡成瘾的影响尚未见到报道。本实验考察冲动性对吗啡诱导的条件性位置偏爱及行为敏感化的影响。实验采用延迟奖赏模型将大鼠的冲动性区分为高、中、低三个水平, 每个水平设置吗啡处理组和盐水处理组。结果发现：动物对吗啡诱导的条件性位置偏爱的程度表现为低冲动组>中冲动组>高冲动组, 并且中、低冲动组动物形成了条件性位置偏爱而高冲动组没有形成这种偏爱; 在行为敏感化表达期, 与相应的盐水组比较, 高、中冲动组动物的吗啡运动激活效应显著, 而低冲动组没有达到显著水平。这些结果提示, 条件性位置偏爱任务中, 动物的冲动性越高, 吗啡的强化效应越低; 行为敏感化任务中, 动物的冲动性越高, 吗啡的运动激活效应越高。由此可见, 动物的冲动性对吗啡诱导的条件性位置偏爱及行为敏感化的影响存在差异。     

抑郁情绪大学生反应抑制的眼动特点

本研究采用反眼动实验范式,通过BDI和 SDS量表筛选11名抑郁情绪组和12名正常对照组被试,以高兴、中性和悲伤面孔图片作为实验材料,旨在探讨抑郁情绪大学生对情绪刺激的眼动抑制能力。结果发现：抑郁情绪组的正确眼跳反应时慢于正常组;反朝向眼跳任务中,抑郁情绪组在情绪面孔图片,尤其是悲伤面孔图片上的错误率比正常组高。研究表明,抑郁情绪个体的认知加工速度慢于正常个体,且对情绪面孔,尤其对悲伤面孔存在抑制缺陷。     

语言产生过程中非目标语言的激活与抑制

运用长时重复启动范式, 探讨熟练和非熟练中－英双语者语言产生过程中非目标语言的激活与抑制。实验1探讨双语被试在学习阶段使用中文进行图片命名任务时, 非目标语言英文概念层面的激活与抑制情况, 结果发现, 两种熟练水平的被试均没有出现重复启动效应; 实验2探讨双语被试在学习阶段使用英文进行图片命名任务时, 非目标语言中文概念层面的激活与抑制情况, 结果发现, 熟练双语被试没有出现重复启动效应, 而非熟练双语被试出现了重复启动效应; 实验3探讨非熟练双语被试在学习阶段使用英文进行图片命名任务时, 非目标语言中文词汇层面的激活与抑制情况, 结果没有出现重复启动效应。综合三个实验的结果可以表明, 熟练中－英双语者语言产生过程中在概念层面上就对非目标语言(不管是一语还是二语)进行了抑制, 而非熟练中－英双语者使用一语时可以在概念层面上抑制非目标语言(二语), 但使用二语时不能在概念层面上抑制非目标语言(一语), 要在词汇层面上才能抑制非目标语言(一语)。     

PIONEER IN BEHAVIORAL PHARMACOLOGY: A TRIBUTE TO JOSEPH V. BRADY

The contributions of Joseph V. Brady to behavioral pharmacology span more than 50 years and range from early studies using the Estes-Skinner (conditioned emotional response) procedure to examine drug effects and various physiological processes in experimental animals to the implementation of mobile methadone treatment services and to small group behavioral analyses in simulated space environments. This expansive range of activities is based on Brady's insight and innovative use of behavioral procedures, his spirited and unabashed enthusiasm for the discipline and its philosophical underpinnings, together with a collegiality and commitment to the experimental analysis of behavior that is both legendary and inspirational. These contributions are summarized and highlighted in this tribute that focuses primarily on Brady's contributions to behavioral pharmacology but which also acknowledges his conceptual and technical contributions spanning multiple disciplines.     

7～9岁儿童失言理解与执行功能的关系

为了说明学龄儿童心理理论与执行功能的关系,研究采用失言理解、威斯康星卡片分类和汉诺塔任务分别考察了90名7—9岁儿童的心理理论和执行功能。结果表明,失言理解与抑制-转换能力相关显著（r=0．34,P〈0．01）,但是与计划能力相关不显著（r=0．06,P〉0．05）。在控制年龄后,失言理解与抑制-转换能力的相关仍然显著（r=0．29,P〈0．05）。研究结果说明,学龄儿童心理理论与执行功能的相关模式与学龄前儿童完全一致,提示心理理论与执行功能的相关关系从学龄前延续到了学龄阶段。     

Hippocampal low-frequency stimulation and chronic mild stress similarly disrupt fear extinction memory in rats

Disruptions of fear extinction-related potentiation of synaptic efficacy in the connection between the hippocampus (HPC) and the medial prefrontal cortex (mPFC) have been shown to impair the recall of extinction memory. This study was undertaken to examine if chronic mild stress (CMS), which is known to alter induction of HPC–mPFC long-term potentiation, would also interfere with both extinction-related HPC–mPFC potentiation and extinction memory. Following fear conditioning (5 tone-shock pairings), rats were submitted to fear extinction (20 tone-alone presentations), which produced an increase in the amplitude of HPC–mPFC field potentials. HPC low-frequency stimulation (LFS), applied immediately after training, suppressed these changes and induced fear return during the retention test (5 tone-alone presentations). CMS, delivered before fear conditioning, did not interfere with fear extinction but blocked the development of extinction-related potentiation in the HPC–mPFC pathway and impaired the recall of extinction. These findings suggest that HPC LFS may provoke metaplastic changes in HPC outputs that may mimic alterations associated with a history of chronic stress.     

The development of attention and response inhibition in early childhood

The goal of this study was to examine the development of attention and response inhibition from ages 5 to 7. Forty children (20 5‐year‐olds and 20 7‐year‐olds) completed four counterbalanced phases of a continuous performance task. Phase 1 was designed to measure attention without distraction, Phase 2 was designed to measure attention with distraction, Phase 3 was designed to measure attention and response inhibition without distraction, and Phase 4 was designed to measure attention and response inhibition with distraction. With regard to attention, 7‐year‐olds performed significantly better than 5‐year‐olds. This age difference was more pronounced when distraction was present. With regard to response inhibition, there were no significant age differences. These results appear to suggest that attention improves between ages 5 and 7 but response inhibition does not. However, conclusions regarding response inhibition were limited because the distraction appeared to have had too powerful an effect on the 5‐year‐olds. Implications and future directions are discussed. Copyright © 2008 John Wiley & Sons, Ltd.