Positive contrast, negative induction, and inhibitory stimulus control in the rat

In Experiment I, 24 rats were trained on a multiple variable-interval variable-interval schedule with a doorlight and white noise serving as component cues. Two groups were then shifted to a multiple extinction variable-interval schedule, and a third group was maintained on the multiple variable-interval variable-interval schedule. The multiple extinction variable-interval condition produced positive contrast when either the light or noise signalled extinction, and both of these cues acquired inhibitory stimulus control as measured by a combined cue test. In Experiment II, the multiple variable-interval variable-interval condition was shifted to multiple extinction variable-interval for one group, to multiple variable-time variable-interval for a second group, and was unchanged for the third group. The two experimental conditions produced identical patterns of response-rate reduction in the altered component, but the multiple extinction variable-interval condition produced positive contrast, whereas the multiple variable-time variable-interval condition did not. Subsequent combined cue and resistance to reinforcement tests revealed that the cue signalling extinction acquired stronger inhibitory stimulus control than the cue signalling variable time.     

Signalled free-operant avoidance of shock by pigeons pecking a key

Two pigeons were trained to peck a key under a free-operant avoidance schedule. Then, changes in key color signalled the beginning (safe period) and the end (warning period) of the response-shock interval, with a response required to change the key color. Finally, a change in key color signalled the warning period and either a response or a shock reinstated the safe stimulus. During signalled avoidance, response rate was higher during the warning stimulus than during the safe stimulus. More responding tended to occur in the warning stimulus when it was terminated by either a response or a shock than by only a response. In either procedure, response latency during the warning stimulus was a function of the duration of the warning stimulus. In general, response and shock rate were higher during unsignalled than during signalled avoidance. When the warning stimulus was brief, the results were similar to those of unsignalled avoidance. These results confirm previous findings with pigeons, are in general agreement with data provided by other species in studies of signalled avoidance, and thereby indicate the transituationality of the key-pecking operant.     

Fitting cross-classification table data to models when observations are subject to classification error

Individuals are classified in a cross-classification table where two behavioral observations on each individual determine the classification. The problem is to test certain structural models assumed to underlie the cross-classified observations. A minimum chi-square test procedure is proposed.     

BEHAVIOR ANALYSIS APPLIED TO ENVIRONMENTAL/ECOLOGICAL PROBLEMS; A REVIEW1

Recent applications of operant technology, including the manipulation of environmental conditions and response consequences, have been directed toward the improvement of man-environment relations. This document summarizes the research designs, procedures, results, and conclusions of these recent behavioral interventions for ecological rebalance. Each of the 32 studies reviewed was undertaken since 1970; all studies were relatively successful in changing the probability of an ecology-related response; all studies incorporated basic methodologies applicable for large-scale, community programs; most of the investigations were conducted in field settings (e.g., college campuses, grocery stores, mobile-trailer parks, homes, movie theaters, public campgrounds, and a football stadium). Several of the studies are as yet unpublished. Sources for receiving documentation of the unpublished research are provided in this document. About 50% of the investigations reviewed were designed to influence behaviors related to environmental litter; the others were of behavior-modification programs that substantially increased bus-ridership, decreased lawn-trampling, promoted the purchase of drinks in returnable rather than throwaway containers, initiated a recycling process, or reduced energy consumption. Essentially, the interventions were either preventive in nature (i.e., designed to discourage environment-destructive behaviors before they occur), or remedial (i.e., designed to encourage behaviors that correct an existing environmental problem). Usually, the preventive measures emphasized responses priming (or prompting), while the corrective measures applied some form of positive reinforcement. Response priming was accomplished with modelling techniques, or with written and/or verbal prompts presented either publicly or on a personal, one-to-one basis. Among the positive reinforcement procedures were field applications of token economies, lottery systems, feedback programming, and intergroup contests, as well as individual contingency contracting. Some experimental designs provided for comparisons between the behavioral effects of response priming and positive reinforcement.     

Dimensional stimulus control following brief wavelength training

Pigeons with extensive training pecking a key illuminated by a white line then had brief training with the key illuminated by 555 nanometers. This was immediately followed by a wavelength generalization test in extinction. Dimensional stimulus control about the training wavelength increased with the duration and number of reinforcements given on variable-interval 30-sec and variable-interval 10-sec schedules in Experiment I. In Experiment II, dimensional stimulus control was obtained after only 4 min of wavelength training from birds with prior and independent discrimination training. Experiment III provided groups equated in number of reinforcers with groups in Experiment I and two 8-min duration groups. Analyses, which included results from both Experiments I and III, showed that dimensional stimulus control increased: (a) more rapidly as a function of the duration of variable-interval 10-sec than variable-interval 30-sec reinforcement; (b) at the same rate across variable-interval reinforcement schedules, as a function of the number of reinforcers available during brief wavelength training.     

Food deliveries during the pause on fixed-interval schedules

Pigeons were trained on fixed-interval schedules of food delivery. In Experiments I and II, the fixed interval was initiated by the previous fixed-interval reinforcer; in Experiment III, the fixed interval was initiated by the first key peck following the preceding fixed-interval reinforcer (a chain fixed-ratio one, fixed-interval schedule). During the postreinforcement pause, variable-time schedules delivered food independent of any specific response. Rate of food delivery during the pause had only small effects on pause duration in Experiments I and II. In Experiment III, however, pause duration increased systematically with the rate of food delivery during the pause. These data suggest that the momentary proximity to reinforcement delivered via the fixed-interval schedule exerts potent control over pause termination. Additional analysis revealed that pause termination was unaffected by the intermittent delivery of food during the pause. Such data suggest that the temporal control by fixed-interval schedules is highly resistant to interference.     

回避与趋近性负性人格特质对应激心血管反应模式的不同影响

本研究考察了回避与趋近性负性特质对不同强度心理社会应激刺激重复暴露的心血管反应、应激后心血管反应恢复、重复应激心血管反应的影响,并探讨了应激认知评价在其中的作用。167名大学生被试被随机分配到中/高强度应激条件中,连续采集其在基线期、首次应激期、恢复期、重复应激期四个阶段的心血管反应数据。结果发现:(1)无论应激强度如何,回避性负性特质预测首次和重复应激中较低(钝化)的心血管反应和应激后较差的恢复,而趋近性负性特质预测较大的心血管反应和应激后较差的恢复。(2)重复应激个人资源感知在回避性负性特质与重复应激心率反应之间起中介作用。因此,回避性负性特质与持续较低(钝化)的应激心血管反应和应激后较差的恢复相联系,而趋近性负性特质与较大的应激心血管反应和应激后较差的恢复相联系,即两类负性特质均表现出不适应的固化的应激心血管反应模式,这可能构成了两类不同负性特质增加罹患心血管疾病风险的生理机制。     

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。     

助推手卫生的行为干预策略

保持手卫生是感染防控的重要策略,但是如何提高其依从性成为预防传染性疾病和减少医疗机构获得性感染的一大挑战。以行为科学为基础的手卫生助推干预以更“隐性”的方式将洗手转变为一种可自动触发的行为习惯,弥补了以知识分享和健康宣教为主的传统手卫生干预策略的诸多局限性。基于影响机制的不同,手卫生助推干预策略可分为提供决策信息、优化决策选项、影响决策结构、提醒决策方向4个大类的框架体系。多模式助推策略的有效性也已在实践中得到印证,但目前还非常缺乏在中国社会文化情境下开展的助推洗手行为的干预研究,今后可尝试基于行为科学理论有针对性地在医院、学校和社区等公共场所开展此类干预研究和实践,为感染防控、疾病预防和改善公共健康做出相应的贡献。     

类别注意控制定势在注意捕获中的加工机制

注意捕获是指注意定向的过程中刺激不自觉地捕获注意的现象。在复杂的视觉搜索任务中,类别注意控制定势(cACS)能够帮助我们将注意引导到与目标定义类别匹配的刺激上,并对其进行优先加工。探讨cACS在注意捕获中的加工机制,不仅能够扩展注意捕获领域的理论研究,还能对实际生活提供指导。通过文献梳理,从cACS的作用阶段、cACS的加工强度及cACS作用时的激活脑区三个方面总结了注意捕获中的cACS的加工机制。未来研究可以就抑制分心物的ACS、不同类型的cACS加工差异和人工类别ACS加工过程等进行探讨。