Responding for sucrose and wheel-running reinforcement: effects of sucrose concentration and wheel-running reinforcer duration

Six male albino rats were placed in running wheels and exposed to a fixed-interval 30-s schedule of lever pressing that produced either a drop of sucrose solution or the opportunity to run for a fixed duration as reinforcers. Each reinforcer type was signaled by a different stimulus. In Experiment 1, the duration of running was held constant at 15 s while the concentration of sucrose solution was varied across values of 0, 2.5. 5, 10, and 15%. As concentration decreased, postreinforcement pause duration increased and local rates decreased in the presence of the stimulus signaling sucrose. Consequently, the difference between responding in the presence of stimuli signaling wheel-running and sucrose reinforcers diminished, and at 2.5%, response functions for the two reinforcers were similar. In Experiment 2, the concentration of sucrose solution was held constant at 15% while the duration of the opportunity to run was first varied across values of 15, 45, and 90 s then subsequently across values of 5, 10, and 15 s. As run duration increased, postreinforcement pause duration in the presence of the wheel-running stimulus increased and local rates increased then decreased. In summary, inhibitory aftereffects of previous reinforcers occurred when both sucrose concentration and run duration varied; changes in responding were attributable to changes in the excitatory value of the stimuli signaling the two reinforcers.     

Metaphors in behavioral genetics

Behavioral geneticists sometimes use metaphorsto describe the role of genes in humanbehavior. In this paper, five sample texts areanalyzed: a popular book, a textbook, ascientific review article, and two originalscientific articles representing differentapproaches in behavioral genetics. Metaphorsare found in all the different kinds of sampletexts, not only in the popular book and thetextbook. This suggests that metaphors are usednot only for rhetorical or pedagogical purposesbut play a more fundamental role in scientificunderstanding. In the sample texts, themetaphors tend to be antideterministic, i.e.,they do not imply genetic determinism butstress the interaction of multiple genes andmultiple environmental factors. No conclusioncan be drawn, however, as to whetherantideterminism is representative ofpresent-day behavioral geneticists in general.Certain historically important metaphors thatmay imply genetic determinism are qualified,avoided, or explicitly rejected. There aretensions between some of the metaphors, makingthem difficult to combine. All the metaphorsthat are used appear empirically apt, howeversometimes only with certain qualifications.     

Beyond the Obvious: Chronic Vividness of Imagery and the Use of Information in Decision Making

The authors investigate two competing hypotheses about how chronic vividness of imagery interacts with the vividness and salience of information in decision making. Results from four studies, covering a variety of decision domains, indicate that chronic imagery vividness rarely amplifies the effects of vivid and salient information. Imagery vividness may, in fact, attenuate the effects of vivid and salient information. This is because, relative to nonvivid imagers, vivid imagers rely less on information that appears obvious and rely more on information that seems less obvious. This tendency is so robust that vividness of imagery may amplify the effects of vivid information only when this information is the only information available in the decision field. The findings seem to reflect vivid imagers' tendency to totally immerse themselves in a decision problem and scrutinize the available information creatively.     

心算活动机制的研究

心算是一种重要的思维活动,是认知心理学的研究主题之一。心算活动具有明显的问题大小效应,其加工过程与工作记忆和长时记忆存在密切关系。此外,对心算的加工机制进行跨学科（认知心理学、神经科学等）的综合研究,是今后心算研究的主要方向。     

内隐与外显记忆重复学习效果的比较研究

实验采用重学—分离设计 ,分别用知觉辨认和再认测验作为内隐、外显测量的测验方法 ,比较重学—启动测验的结果与重学—再认的结果 ,发现 :重学和间接测量的结合能有效地揭示内隐记忆的叠加现象 ;一次重学能使知觉启动测验的成绩产生明显的叠加效应 ;高意识水平学习后 ,低意识水平的重复学习不能改变外显测验成绩持续下降的趋势。     

Is the inversion effect in rhesus monkeys face-specific?

This study investigated the face inversion effect in rhesus monkeys (Macaca mulatta). Face stimuli consisted of ten black-and-white examples of unfamiliar rhesus monkey faces, brown capuchin faces, and human faces. Two non-face categories included ten examples of automobiles and abstract shapes. All stimuli were presented in a sequential matching-to-sample format using an automated joystick-testing paradigm. Subjects performed significantly better on upright than on inverted presentations of automobiles, rhesus monkey and capuchin faces, but not human faces or abstract shapes. These results are inconsistent with data from humans and chimpanzees that show the inversion effect only for categories of stimuli for which subjects have developed expertise. The inversion effect in rhesus monkeys does not appear to be face-specific, and should therefore not be used as a marker of specialized face processing in this species. Received: 18 November 1998 / Accepted after revision: 9 May 1999     

关联效应的实验研究

对汉语双字词的关联效应进行了实验研究,结果发现：语义关联效应显著,而语音关联效应则不存在。被试对各词再认判断确信程度和使用频率判断的模糊统计结果,在一定程度上验证了模糊痕迹理论的概括性表征、细节性表征和梗概抽取等观点,并在一定程度上验证了记忆归因理论。     

The interaction between schizotypy and latent inhibition: modulation by experimental parameters

Two recent experiments (Della Casa et al., in press) yielded the typical reduced latent inhibition (LI) in high vs low schizotypy subjects after a slow, irregularly presented masking task (Stroop task), and reduced LI in low vs high schizotypy subjects after a fast, regularly presented masking task. The present experiment was aimed at testing whether speed or regularity was responsible for the different results. The present slow, regular experiment replicated the results of the former slow, irregular experiment, i.e. reduced LI in high schizotypals and significant LI in low schizotypals, indicating that speed and not regularity is the critical experimental variable. The modulation of the schizotypy—latent inhibition relationship can be attributed to differences in attentional resources or the time available to process the to-be-target stimuli during preexposure, in accordance with the hypothesis of Lubow and Gewirtz, 1995 that automatic processing of these stimuli is critical for the development of latent inhibition in adult humans. In addition, results on Stroop and negative priming effects are presented.     

Bidirectional semantic associations between social power and weight

Two experiments were conducted to examine bidirectional semantic associations between power and weight using a priming paradigm. Bidirectionality in the relationship between power and weight was demonstrated, utilising tasks that were identical except that the orders in which the stimuli were presented were reversed. In Experiment 1, an empty scale leaning either leftward or rightward was used as a priming stimulus, and a scale that appeared in equilibrium with a pair of power words was used as a target stimulus. In Experiment 2, a scale with a pair of words that appeared in equilibrium was used as a priming stimulus, and an empty scale leaning either leftward or rightward was used as a target stimulus. We identified interaction effects between power and weight in both experiments. Associations between power and weight provide evidence for both conceptual metaphor views and evolutionary theory. The bidirectionality of metaphorical effects is in line with the strong version of metaphoric structuring. Both language and experiential correlations play important roles in the development of the mapping between power and weight.     

Testing emotional memories: does negative emotional significance influence the benefit received from testing?

A large body of research shows that emotionally significant stimuli are better stored in memory. One question that has received much less attention is how emotional memories are influenced by factors that influence memories after the initial encoding of stimuli. Intriguingly, several recent studies suggest that post-encoding factors do not differ in their effects on emotional and neutral memories. However, to date, only detrimental factors have been addressed. In the present study, we examined whether emotionally negative memories are differentially influenced by a well-known beneficial factor: the testing of memories. We employed a standard cued recall testing-effect paradigm where participants studied cue-target pairs for negative and neutral target pictures. In a subsequent post-encoding phase, one third of the cue-target pairs were tested and one third restudied; the remaining third served as control pairs. After one week, memory for all cue-target pairs was tested. While replicating both the testing effect and the emotional enhancement effect, no differences between negative and neutral memories in the benefits received from testing and restudying were observed. Thus, it seems to be true that post-encoding factors do not influence emotional memories in any other way than neutral memories, even when they are beneficial.