经济学评价在临床决策中的应用探讨

医生在临床工作中做出明确诊断,并据此给予有效的处理均属于决策过程。制定决策的整个过程,同时也是进行决策思维的过程。近年来,高新技术的迅猛发展以及医疗费用急剧增加,使制定决策更加复杂。如何进行正确的决策思维,做出最切实可行的和最佳的决策,对避免决策的盲目性具有重要的现实意义。     

工作记忆中的注意焦点转换

在工作记忆中的选择性注意及注意焦点机制的基础上,从3个方面回顾了对工作记忆中注意焦点转换的研究：（1）工作记忆中的注意焦点转换的概念及其基本研究方法;（2）影响注意焦点转换代价的因素,包括提取、复述、加工、更新和记忆集大小等;（3）注意焦点转换与工作记忆各功能成分之间的关系,包括注意焦点转换与工作记忆执行功能的关系,注意焦点转换反映的存储、加工和执行功能之间的相互关系,注意焦点转换与工作记忆中资源分配的关系。最后,该文展望了未来的研究方向     

The sunk cost effect in pigeons and humans

The sunk cost effect is the increased tendency to persist in an endeavor once an investment of money, effort, or time has been made. To date, humans are the only animal in which this effect has been observed unambiguously. We developed a behavior-analytic model of the sunk cost effect to explore the potential for this behavior in pigeons as well as in humans. Each trial started out with a short expected ratio, but on some trials assumed a longer expected ratio part way through the trial. Subjects had the (usually preferable) option of "escaping" the trial if the longer expected ratio had come into effect in order to bring on a new trial that again had a short expected ratio. In Experiments 1 through 3, we manipulated two independent variables that we hypothesized would affect the pigeons' ability to discriminate the increase in the expected ratio within a trial: (a) the presence or absence of stimuli that signal an increase in the expected ratio, and (b) the severity of the increase in the expected ratio. We found that the pigeons were most likely to persist nonoptimally through the longer expected ratios when stimulus changes were absent and when the increase in the expected ratio was less severe. Experiment 4 employed a similar procedure with human subjects that manipulated only the severity of the increase in the expected ratio and found a result similar to that of the pigeon experiment. In Experiment 5, we tested the hypothesis that a particular history of reinforcement would induce pigeons to persist through the longer expected ratios; the results suggested instead that the history of reinforcement caused the pigeons to persist less compared to pigeons that did not have that history.     

The currency of procurement cost

As the number of instrtumental responses required to procure access to food is increased, animals decrease the frequency of initiating meals and increase meal size, conserving total intake while limiting the increase in the overall cost of feeding. In two studies, one using wheel turns and one using bar presses as the instrumental response, we asked whether freely feeding laboratory rats measure cost according to the energy or the time they expend. In each study we varied both the price (i.e., number of wheel turns or bar presses) and the force required to make a response (i.e., torque on the wheel or weight of the bar). Price affected both procurement time (from the first to the last procurement response) and procurement work, whereas torque and bar weight affected work without altering time in most cases. Meal patterns were altered by all manipulations of price, but changes in torque and bar weight had little effect on meal patterns, except in the conditions in which they altered procurement time. These results suggest that time is a critical currency of procurement cost in rats.     

An ERP study of inhibition of non-target languages in trilingual word production

The present study examined the locus where inhibition of non-target languages is exerted during trilingual word production by analyzing the cue-locked and stimulus-locked ERPs respectively in the n-2 language repetition paradigm. During the experiment, Uighur–Chinese–English trilinguals overtly named Arabic digits in one of their three languages according to a visually presented cue while their behavioral and electrophysiological responses were recorded. The behavioral data revealed insignificant n-2 repetition costs. Cue-locked ERPs revealed also only tiny or marginally significant n-2 repetition effects over some midline electrodes. The stimulus-locked ERP data showed a more negative ERP component elicited by the n-2 repetition trials than the n-2 non-repetition trials around 250 ms after stimulus onset, but no significant difference in this ERP effect between different languages was found. The results indicate that inhibition of non-target languages occurs at the lemma selection phase rather than the language task schemas phase during trilingual language production.     

双语词汇理解切换中非目标语言加工

实验采用直接语音掩蔽启动范式,通过掩蔽词的有、无呈现对切换后单词的读音判断反应时产生影响,进而了解非熟练双语者双语理解切换中非目标语言加工状态。实验结果表明,无呈现掩蔽词组的反应时比有呈现组的判断反应时长;不同掩蔽词呈现时间两组中切换反应时判断不显著。实验证明无论是哪一种语言作为非目标语言,其在词汇层上均都不会被激活;双语词汇理解切换中,切换至熟练语言比切换至不熟练语言切换代价小。     

Reward prospect interacts with trial-by-trial preparation for potential distraction

When attending for impending visual stimuli, cognitive systems prepare to identify relevant information while ignoring irrelevant, potentially distracting input. Recent work showed that a supramodal distracter-filtering mechanism is invoked in blocked designs involving expectation of possible distracter stimuli, although this entails a cost (distraction-filtering cost) on speeded performance when distracters are expected but not presented. Here we used an arrow-flanker task to study whether an analogous cost, potentially reflecting the recruitment of a specific distraction-filtering mechanism, occurs dynamically when potential distraction is cued trial-to-trial (cued distracter-expectation cost). In order to promote the maximal utilization of cue information by participants, in some experimental conditions the cue also signalled the possibility of earning a monetary reward for fast and accurate performance. This design also allowed us to investigate the interplay between anticipation for distracters and anticipation of reward, which is known to engender attentional preparation. Only in reward contexts did participants show a cued distracter-expectation cost, which was larger with higher reward prospect and when anticipation for both distracters and reward were manipulated trial-to-trial. Thus, these results indicate that reward prospect interacts with the distracter expectation during trial-by-trial preparatory processes for potential distraction. These findings highlight how reward guides cue-driven attentional preparation.     

Selective,but Only if It Is Free: Children Trust Inaccurate Individuals More when Alternative Sources Are Costly

The present research examines the effect of the costliness of an information source on children's selective learning. In three experiments (total N = 112), 4‐ to 7‐year‐olds were given the opportunity to acquire and endorse information from one of two sources. One source, a computer, was described as always accurate; the other source, a puppet, had a history of either accuracy or inaccuracy. For some children, learning from the computer required giving away stickers. The costliness of the computer clue reduced children's use of this source across all experiments, but its effect on children's use of the puppet varied based on the puppet's accuracy and the type of information learned. Children's trust in the puppet was above chance regardless of the cost of the computer when they were learning generalizable semantic information and the puppet had a history of accuracy. When the puppet was inaccurate or when children learned episodic information, the costliness of the computer significantly increased children's trust in the puppet. Hence, attaching a cost to a preferred knowledge source reduces children's selectivity and increases their trust in sources that they would not otherwise see as desirable. Copyright © 2013 John Wiley & Sons, Ltd.     

Mental Set Shifting in Childhood: The Role of Working Memory and Inhibitory Control

The role of working memory (WM) and inhibition in mental set shifting was examined from an individual difference perspective in children aged 5–14 years (N = 117). Using the Hearts and Flowers task the rationale of the present study was to directly test the theoretical assumption that mental set shifiting in childhood primarily builds on WM and inhibitory processes. Theoretical predictions about WM and inhibitory demands in the congruent and incongruent conditions of the Hearts and Flowers task were also considered because these blocks underlie relevant measures of set shifting. The findings show that both WM and inhibition (extracted as factors in confirmatory factor analysis) are important for set shifting but that this general association is driven by the link between these executive functions (EFs) and the goal‐representation aspect (i.e. global switch costs) of shifting, rather than to the actual switch‐implementation process (i.e. local switch costs). In addition, our findings are novel in showing that, despite a substantial correlation between the two EF components, it was the variance specific to WM and inhibition that was important for mental set shifting. Copyright © 2014 John Wiley & Sons, Ltd.