Stimulus conditions affecting rate of acquisition in a computer-operated version of the two-way active avoidance procedure

Several experiments were performed with rats in order to investigate the stimulus conditions affecting the rate of acquisition of two-way active avoidance. The number of trials per session, the duration of the Conditioned Stimulus (CS), the intertrial interval (pause time), and the intensity of the shock presentation were each varied in separate experiments. The optimal, yet practicable, conditions required to obtain a fast rate of acquisition included 40 to 60 trials per session, a 40-sec intertrial interval, a 10-sec Conditioned Stimulus presentation and a shock intensity of 1.0 mA. These results are discussed with regard to the problem of standardization in behavioral research manipulating biological independent variables.     

Repetition effects on word fragment completion: The role of competition among responses

Four experiments examined the effect of spaced repetition of study words on completion of word fragments with only one solution and word fragments with multiple solutions. Recognition was used as test of explicit memory in the first two experiments. The study words were presented either once or three times. Repetition was found to increase recognition memory substantially, and to affect fragment completion performance only marginally. This was true for both single- and multiple-solution fragments, showing that competition among responses is not critical for the magnitude of the repetition effect in fragment completion. This finding, that the repetition effect is marginal also when the type of cues provides an occasion for repetition effects to show up, suggests that the real effect of repetition on perceptual priming is borderline. It is proposed that memory from the first presentation eliminates necessary processing of items when they are re-exposed, and that the repetition effect thereby is reduced.     

Instructed versus pharmacological effects of alcohol in alcoholics and social drinkers

Twelve alcoholics and 12 social drinkers were studied in an experiment where instructions about alcohol or placebo were orthogonally crossed with administration of alcohol or placebo in a Balanced Placebo Design. Three subjects were simultaneously observed while watching soccer games on the TV together and having free access to a mixed drink, which in the alcohol conditions contained 150ml of 80% proof vodka. The assessment procedure included several aspects of drinking behavior, behavioral observations during the session, psychiatric ratings and nurse observations before and after each session, ratings for craving, self-reported state anxiety and physiological changes (heart rate and blood pressure). In general, the results showed the alcoholic's behavior to be controlled by instruction-induced expectancies rather than by the actual beverage given, whereas the social drinkers showed tendencies in the opposite direction. The implications of these results for the traditional disease conception of alcoholism and for learning theory approaches are discussed.     

Decomposing the encoding of action events: A dual conception

Two experiments are reported in which we tested the hypothesis that encoding of verbal features of subject-performed tasks or SPTs (e.g., bounce the ball, lift the spoon) is attention-demanding and effortful, whereas physical features of this memory task (e.g., color, weight) are acquired with little effort, and without deliberate encoding strategies. In Experiment 1, subjects were asked to perform a series of SPTs and were examined on recall of verbal instructions and colors of objects involved under conditions of focused or divided attention. In Experiment 2, performance of a series of SPTs was followed by recall of verbal instructions and recall of weights of objects involved. Results of both experiments indicated that recall of the verbal task component was negatively affected by requirements of dual-task performance, whereas recall of both physical task features was equally good in both encoding conditions. The obtained pattern of outcome is interpreted as supportive of the dual conception hypothesis of the nature of the encoding of action events.     

Perception of autonomic reactions and actual heart rate in phobic patients

The relationship between perceived physiological arousal and actual heart-rate reactions was studied in two behavioral test situations. The subjects were 70 phobic patients (34 social phobics and 36 claustrophobics) who were given the general form of the Autonomic Perception Questionnaire about 1 month before the respective behavioral test and the specific form immediately after the test. The results showed significant correlations between APQ and actual heart rate for the social phobics, while the picture was more complicated for the claustrophobics. The implications of these results are discussed.This research was supported by Grant 05452 from the Swedish Medical Research Council.     

Overt repetition as a means of controlling rehearsal

Abstract.— Three different ways of using the concept of rehearsal were discussed. Examples were presented showing confusions in the literature due to a failure to distinguish these three definitions. A free recall experiment was conducted with the purpose of investigating three problems relating to the concept of rehearsal: ( a ) an unclear relationship between overt and covert repetition, ( b ) whether overt repetition excluded other control processes, and (c) whether a shallow repetition produces a permanent memory trace or not. Using a pronounced time pressure it was demonstrated first that overt repetition facilitated recall performance of recency items and that recall of primacy items was facilitated by covert repetition. Secondly, it was shown that overt repetition did not exclude other types of encoding. Finally, a shallow maintaining repetition did not produce a permanent memory trace. The results are interpreted as supporting a level of processing point of view rather than a multistore approach.     

A token economy program for chronic schizophrenic patients

Abstract.— A token economy program was applied on a ward for 12 chronic schizophrenic patients. An ABABC-design, i.e. a group reversal design with a noncontingent reinforcement phase at the end, was used to evaluate the treatment. The patients' activity-level increased from baseline to the treatment phase. During the reversal period the activity-level decreased but it increased again when the token economy was reintroduced. The non-contingent reinforcement resulted in the predicted decrease for two of the six behaviors recorded. Five of the twelve patients were discharged from the ward during the 8-month program period and none of them had been readmitted at the end of the one year follow-up. Individual treatment programs for two of the patients concerning aggressive acts, deficient eye-contact and lip-biting are described.     

不安全依恋者注意偏向的形成机制及神经基础

不安全依恋者的注意偏向是指依恋焦虑和回避个体对依恋信息产生或趋近或回避的注意偏好, 这一注意偏好使得个体形成了处理与依恋对象关系的特殊认知机制：依恋回避个体偏好采用防御性机制, 倾向于回避对依恋信息的注意; 依恋焦虑个体偏好采用夸大性机制, 倾向于夸大威胁性信息, 因而会积极寻求与依恋对象的亲近。不安全依恋者注意偏向的差异主要体现在情绪信息、痛觉感受和工作记忆三个方面; 加工阶段特征主要涉及P1、N1波等代表的注意自动加工和LPP波代表的注意控制加工; 脑网络上主要包括两个子网络, 即负责情绪评估的边缘系统和负责情绪调节的以前额叶为代表的神经网络。未来研究中更应该关注刺激物的生态效度, 检验依恋系统是否激活, 不安全依恋者注意偏向的自动加工和控制加工阶段的关系, 不安全依恋者注意偏向产生的分子遗传机制以及注意偏向的跨文化研究。     

有“新”同享：共有消费促进对不熟悉产品的选择*

共有消费是多位消费者共同参与并承担开销的一种常见的消费活动。本研究基于风险转移理论, 探究了消费情境(单独消费vs.共有消费)对不熟悉产品偏好的作用机理及边界条件。通过5个实验, 结果发现：相比于单独消费情境下的消费者, 在共有消费情境下的消费者更愿意尝试不熟悉的产品。原因在于共有消费情境会转移消费风险, 使得消费者对不熟悉产品的感知风险降低。但是该效应仅发生于产品风险较低的产品。同时, 当共有消费群体的关系较为疏远时, 该效应会消失甚至逆转。