Human observing: Maintained by stimuli correlated with reinforcement but not extinction

College students received points exchangeable for money (reinforcement) on a variable-time 60-second schedule that alternated randomly with an extinction component. Subjects were informed that responding would not influence either the rate or distribution of reinforcement. Instead, presses on either of two levers (“observing responses”) produced stimuli. In each of four experiments, stimuli positively correlated with reinforcement and/or stimuli uncorrelated with reinforcement were each chosen over stimuli correlated with extinction. These results are consistent with prior results from pigeons in supporting the conditioned-reinforcement hypothesis of observing and in not supporting the uncertainty-reduction hypothesis.     

The conditioned reinforcement of repeated acquisition

Three monkeys were trained to emit a chain of three responses on three separate levers in a set of six levers to obtain food. The chain producing food (correct chain) was changed each day. During a trial, a press on any lever produced a feedback stimulus; a press on a correct lever produced an additional distinctive stimulus; the third correct press produced a food pellet. Test sessions in which either the food or the distinctive stimuli were removed were interspersed with baseline sessions. In tests without food presentations, the subjects acquired the correct chain rapidly, with a level of accuracy comparable to baseline. Removing the distintive stimuli for either the first or second member of the correct chain greatly retarded acquisition of that member of the chain. Removing all distinctive stimuli often reduced accuracy throughout the chain to chance level, even though food was presented following each correct chain. These results were interpreted as evidence that the distinctive stimuli presented after correct responses functioned as conditioned reinforcers. Reductions in accuracy following an omitted distinctive stimulus indicated that they were also discriminative stimuli for correct responding in their presence.     

Contiguity and conditioned reinforcement in probabilistic choice

In a baseline condition, pigeons chose between an alternative that always provided food following a 30-s delay (100% reinforcement) and an alternative that provided food half of the time and blackout half of the time following 30-s delays (50% reinforcement). The different outcomes were signaled by different-colored keylights. On average, each alternative was chosen approximately equally often, replicating the finding of suboptimal choice in probabilistic reinforcement procedures. The efficacy of the delay stimuli (keylights) as conditioned reinforcers was assessed in other conditions by interposing a 5-s gap (keylights darkened) between the choice response and one or more of the delay stimuli. The strength of conditioned reinforcement was measured by the decrease in choice of an alternative when the alternative contained a gap. Preference for the 50% alternative decreased in conditions in which the gap preceded either all delay stimuli, both delay stimuli for the 50% alternative, or the food stimulus for the 50% alternative, but preference was not consistently affected in conditions in which the gap preceded only the 100% delay stimulus or the blackout stimulus for the 50% alternative. These results support the notion that conditioned reinforcement underlies the finding of suboptimal preference in probabilistic reinforcement procedures, and that the signal for food on the 50% reinforcement alternative functions as a stronger conditioned reinforcer than the signal for food on the 100% reinforcement alternative. In addition, the results fail to provide evidence that the signal for blackout functions as a conditioned punisher.     

Context effects on choice.

Four pigeons responded on a concurrent-chains schedule in four experiments that examined whether the effectiveness of a stimulus as a conditioned reinforcer is best described by a global approach, as measured by the average interreinforcement interval, or by a local contextual approach, as measured by the onset of the stimulus preceding the conditioned reinforcer. The interreinforcement interval was manipulated by the inclusion of an intertrial interval, which increased the overall time to reinforcement but did not change the local contingencies on a given trial A global analysis predicted choice for the richer alternative to decrease with the inclusion of an intertrial interval, whereas a local analysis predicted no change in preference. Experiment 1 examined sensitivity to intertrial intervals when each was signaled by the same houselight that operated throughout the session. In Experiment 2, the intertrial interval always was signaled by the stimulus correlated with the richer terminal link. In Experiment 3, the intertrial interval was signaled by the keylights correlated with the initial links and two novel houselights. Experiment 4 provided free food pseudorandomly during the intertrial interval. In all experiments, subjects' preferences were consistent with a local analysis of choice in concurrent chains. These results are discussed in terms of delay-reduction theory, which traditionally has failed to distinguish global and local contexts.     

预期错误与急性应激对不同强度恐惧记忆提取消退的影响

在条件性恐惧记忆再巩固模型下, 预期错误被证明是引发记忆不稳定的必要条件, 但其在不同强度恐惧记忆下的作用尚不明确。对于高强度可能导致的提取无效, 缺乏相应的探索以寻找解决办法, 而应激(stress)在其中发挥的作用值得探索。本研究考察人类被试中, 预期错误在不同强度恐惧记忆下的作用, 以及提取之后施加外源性应激对于消退进程的影响。结果发现, 对于较弱的恐惧记忆, 单个预期错误提取后消退可显著抑制恐惧自发恢复; 而对于较强恐惧记忆, 单个预期错误不能提取恐惧记忆进入再巩固, 已消退的记忆还会复发; 且在该种情况下, 如果在提取后施加外源性急性应激, 会进一步增大恐惧恢复。     

Punishment and its putative fallout: A reappraisal

In his book Coercion and Its Fallout Murray Sidman argued against the use of punishment based on concerns about its shortcomings and side effects. Among his concerns were the temporary nature of response suppression produced by punishment, the dangers of conditioned punishment, increases in escape and avoidance responses, punishment-induced aggression, and the development of countercontrol. This paper revisits Sidman's arguments about these putative shortcomings and side effects by examining the available data. Although Sidman's concerns are reasonable and should be considered when using any form of behavioral control, there appears to be a lack of strong empirical support for the notion that these potential problems with punishment are necessarily ubiquitous, long-lasting, or specific to punishment. We describe the need for additional research on punishment in general, and especially on its putative shortcomings and side effects. We also suggest the need for more effective formal theories of punishment that provide a principled account of how, why, and when lasting effects of punishment and its potential side effects might be expected to occur or not. In addition to being necessary for a complete account of behavior, such data and theories might contribute to improved interventions for problems of human concern.     

心理应激对青少年运动员T淋巴细胞亚群及IgG、IgA、IgM的影响

目的揭示心理应激对不同性别、训练年限以及不同焦虑特质的青少年射击运动员免疫功能的影响。方法用特质一状态焦虑量表(STAI)测定运动员的状态及特质焦虑;用比浊法测定免疫球蛋白G、A、M的含量;用免疫组化法测定T淋巴细胞亚群的数量。结果①心理应激后IgM的含量显示性别差异,女运动员的IgM浓度高于男运动员。②心理应激后表现为训练年限少的运动员TCD4^ 细胞数量明显少于训练年限长的运动员。③心理应激后表现为高低状态焦虑组运动员IgA含量差异,高焦虑组IgA浓度明显低于低焦虑组．心理应激后高低特质焦虑组之间没有表现出显著性差异。结论男运动员、训练年限少及高状态焦虑青少年运动员心理应激后免疫抑制现象更严重,这是HPA轴及HPG轴等共同作用的结果。     

Getting Students to Choose to Do More Work: Evidence of the Effectiveness of the Interspersal Procedure

College students were exposed to two sets of mathematics assignments. For each set students were given an experimental and a control assignment. The control assignments contained 15 three-digit by two-digit target problems. The experimental assignments contained 18 similar target problems as well as six one-digit by one-digit multiplication problems interspersed after every third target problem. In the first assignment set, students were asked to work each assignment for 5 minutes. Although the experimental assignments contained more target problems, results showed that significantly more students chose the experimental assignment and rated it as less difficult and as requiring less effort to complete. In the second assignment set, students were asked to complete both assignments. Again significantly more students rated the experimental assignment as being less difficult and as requiring less effort to complete. Although more students chose the experimental assignment for homework, this difference was not significant. Discussion focuses on using the interspersal procedure to enhance students' perceptions of assignments and alter their choice behavior.     

先入观念对情绪感染力的调节——以教学活动为例

从以往意识性情绪感染的研究中可以推断出, 情绪感染可以被后继的“观念”所调节, 这种观念可以被无意识提取, 那么情绪感染能不能被“先入观念”所调节呢, 即观念先于情绪感染而存在并对情绪感染的最终效果产生影响。实验情境以教学活动为例, 采用被试内设计, 通过实验前的指导语引导学生树立两种教师评价--“权威”教师(积极的先入观念)和“新手”教师(消极的先入观念), 然后给学生播放两位教师的三类教学视频--中性情绪、积极情绪、消极情绪的朗诵视频, 使用BioNeuro八通道生物反馈仪记录学生在观看视频时的生理指标, 每段视频播放后, 要求学生完成《教师课堂情绪感染力评价问卷(学生用)》。实验结果表明, 学生在观看“权威”教师视频时, 其注意力水平不受教师情绪效价的影响, 学生对“权威”教师均能保持较高的“专注”状态, 从而提高了“权威”教师的积极情绪感染力(易感性调节), 而对“新手”教师的“专注”程度较低, 从而削弱了“新手”教师的积极情绪感染力(免疫性调节)。“新手”教师的消极情绪感染力(倦怠)比“权威”教师的消极情绪感染力更强, 这与学生对“权威”教师的消极情绪进行“合理化”解释有关, 从而免疫了“权威”教师的消极情绪感染力。问卷调查结果也表明, 学生对“权威”教师的情绪感染力评价(无论是中性、积极或消极视频)要极其显著好于对“新手”教师的评价。由此说明, 先入观念对情绪感染的调节方式有两种：“专注”和“合理化”, 调节的结果也有两种：“易感性”与“免疫性”。     

吗啡对不同距离条件下大鼠信号追踪和目标追踪的影响

条件刺激短暂呈现并消失后, 奖赏立即呈现, 多次匹配后诱导出动物对条件刺激(信号追踪)或奖赏呈现装置如食盒(目标追踪)的接近。条件刺激与食盒间的距离是影响信号/目标追踪反应和损害联结学习的重要变量, 成瘾药物能够增加奖赏的诱因动机, 进而增加个体的奖赏寻求行为。距离能否通过损害联结学习而减弱成瘾药物的动机放大作用尚未见到报道。本实验采用autoshaping模型, 考察8、30和60 cm距离条件下吗啡处理对大鼠信号追踪和目标追踪的影响。结果发现：(1)信号追踪随距离增加而减少, 目标追踪对距离不敏感。(2)急性吗啡处理减少8、30和60 cm条件下信号追踪而增加8和60 cm条件下目标追踪, 慢性吗啡处理在8和30 cm条件下减少信号追踪增加目标追踪; 消退检测中, 吗啡前暴露减少8和60 cm条件下信号追踪而增加60 cm条件下目标追踪。(3)辨别反转学习中, 吗啡前暴露使30和60 cm条件下的大鼠偏爱旧信号、辨别力受损, 减少8、30和60 cm条件下大鼠对新信号的接触。这些结果提示, 距离较少影响吗啡的信号追踪抑制作用和目标追踪增强效应, 而易化吗啡前暴露对反转学习的损害。说明距离是易化成瘾药物对联结学习不利影响而非反转其动机放大作用的重要因素。