对体液免疫反应的条件反射性调节

以饮糖精水作为条件刺激(conditioned stimulus,CS),腹腔注射免疫抑制剂环磷酰胺作为非条件刺激(unconditioned stimulus,UCS)训练Wistar大鼠,3天后腹腔注射卵清蛋白(ovalbunfin,OVA)抗原,观察再次单独条件刺激对原发性体液免疫反应的作用。结果发现．一次CU-UCS结合训练导致CS组大鼠对再现糖精水产生厌恶反应,外周血中抗OVA-IgG抗体水平显著低于UCS组。两次CS-UCS结合训练并多次给予条件刺激后,CS组大鼠抗OVA-IgG的条件性免疫抑制效应与一次CS-UCS结合训练及再次给予一次条件刺激的反应类同。这些结果证明条件刺激增强了环磷酰胺对动物原发性体液免疫反应的抑制作用．这种条件性体液免疫抑制作用是相对稳定和有限度的,不易受条件反射建立参数的影响。     

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.     

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.     

条件性恐惧记忆消退返回的性别差异

采用预期判断任务考察男女性对已消退的条件性恐惧记忆是否会出现消退返回的现象。结果表明: (1)在对已习得的条件性恐惧记忆消退后4个小时进行测试, 被试整体会出现明显的消退返回现象; (2)对消退返回现象的性别差异进行比较, 女性比男性的消退返回现象更突出, 并且差异显著; (3)与男性相比, 女性对条件性恐惧记忆具有易习得难消退的趋势, 但是性别差异不显著。研究结果验证了消退返回现象存在的普遍性, 并且有着显著的性别差异, 为以后对创伤后应激障碍患者的治疗应考虑性别因素提供了心理学依据。     

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。     

Incentivizing physical activity using token reinforcement with preschool children

We combined several single‐subject designs to assess the effects of contingent and noncontingent token reinforcement on moderate‐to‐vigorous physical activity (MVPA) exhibited by 4 preschool‐aged children. Higher overall levels and longer bouts of MVPA reliably occurred when tokens were delivered contingent on MVPA for 3 of the 4 children when compared to baseline (no token) and for 2 of the 4 children when compared to noncontingent‐token conditions. The present study demonstrated that the delivery of tokens contingent on MVPA can increase and maintain MVPA exhibited by preschool‐aged children, resulting in more MVPA than in baseline conditions and conditions in which tokens are awarded without respect to MVPA. These results demonstrate that token economies can be used to increase MVPA and they add to the evidence base supporting the use of token economies to address a range of behavior problems.     

Assessing functions of stimuli associated with rich‐to‐lean transitions using a choice procedure

Under fixed‐ratio schedules, transitions from more to less favorable conditions of reinforcement (rich‐to‐lean transitions) usually generate extended pausing. One possible explanation for this effect is that stimuli associated with rich‐to‐lean transitions are aversive and, thus, extended pausing functions as escape. The purpose of this study was to characterize further the aversive function of different transitions, and the stimuli associated with them, by allowing pigeons to choose to complete select ratios in the presence of either a mixed‐schedule stimulus or a transition‐specific multiple‐schedule stimulus. The mixed schedule was preferred during transitions that signaled an upcoming lean reinforcer (rich‐to‐lean and lean‐to‐lean), whereas the multiple schedule was preferred during transitions that signaled an upcoming rich reinforcer (lean‐to‐rich and rich‐to‐rich). These findings support the notion that stimuli associated with rich‐to‐lean (and to some extent lean‐to‐lean) transitions can function aversively; whereas stimuli associated with other transitions (e.g., lean‐to‐rich and rich‐to‐rich) can function as conditioned reinforcers. When the opportunity to choose between schedule‐correlated stimuli was available, however, choice latency was controlled exclusively by the multiple‐schedule stimulus. That is, the opportunity to select the mixed schedule did not attenuate rich‐to‐lean pauses, suggesting that extended pausing may be more than simply escape.     

远期恐惧记忆再巩固更新机制的线索选择性特点

已有动物和人类研究均表明, 通过记忆的再巩固更新机制能有效削弱新形成的条件性恐惧记忆(1天), 并且存在线索选择性特点。然而创伤后应激障碍(PTSD)往往在形成相当一段时间后才能得到治疗, 且现实生活中人们通常一次习得对多个线索的恐惧。因此找到针对多线索创伤记忆的有效治疗方法显得尤为重要。目前未有人研究远期恐惧记忆的再巩固更新机制是否存在线索选择性特点。为探究远期恐惧记忆(>7天)的再巩固更新机制是否同样存在线索选择性特点, 本研究采用被试内实验设计, 以皮肤电作为恐惧反应指标, 多个线索作为条件刺激进行恐惧习得, 习得14天后给被试单独呈现一个线索进行恐惧记忆提取, 10分钟后进行消退训练, 24小时后对不同线索进行自发恢复测试。结果显示：未提取线索的自发恢复程度显著高于提取线索。说明远期记忆(14天)的再巩固更新机制同样存在线索选择性特点, 并确认了提取消退作为一种行为手段对远期恐惧记忆再巩固进行干预的有效性, 对临床干预具有一定指导意义。     

心理神经免疫学研究

心理神经免疫学（Psychoneuroimmunology）是一门探索人类心身健康奥秘的新型边缘学科。它研究神经系统如何将心理因素转换为可以影响健康的生理状态的机制,特别是脑和行为如何影响免疫系统,又如何受到免疫系统的影响的。免疫系统和神经系统之间是否真正存在联系一直有争论,我们实验室围绕高级神经活动对免疫系统的作用开展了研究。工作包括：条件反射性免疫抑制和增强、情绪应激与免疫、心理行为干预与癌症等。这些工作不仅证实了心理调控,比如信号刺激、情绪和意念想象等,确实可以影响免疫系统的功能,而且对有关机制进行了探讨     

论肿瘤免疫的复杂性

免疫系统是一个复杂自适应巨系统,它还具有开放复杂巨系统的所有特征。体内已建立的肿瘤是一个复杂适应系统,两者间的相互作用造就了肿瘤免疫的复杂性。本文从复杂性科学角度阐释肿瘤免疫,以期对肿瘤细胞免疫治疗的研究有所裨益。