Prefrontal brain activity predicts temporally extended decision-making behavior

Although functional neuroimaging studies of human decision-making processes are increasingly common, most of the research in this area has relied on passive tasks that generate little individual variability. Relatively little attention has been paid to the ability of brain activity to predict overt behavior. Using functional magnetic resonance imaging (fMRI), we investigated the neural mechanisms underlying behavior during a dynamic decision task that required subjects to select smaller, short-term monetary payoffs in order to receive larger, long-term gains. The number of trials over which the longterm gains accrued was manipulated experimentally (2 versus 12). Event-related neural activity in right lateral prefrontal cortex, a region associated with high-level cognitive processing, selectively predicted choice behavior in both conditions, whereas insular cortex responded to fluctuations in amount of reward but did not predict choice behavior. These results demonstrate the utility of a functional neuroimaging approach in behavioral psychology, showing that (a) highly circumscribed brain regions are capable of predicting complex choice behavior, and (b) fMRI has the ability to dissociate the contributions of different neural mechanisms to particular behavioral tasks.     

The norms and stability of new measures of the multidimensional body image construct

The measurement of the body image construct has become increasingly multidimensional. New assessments are available to measure various facets of body image functioning: The Body Image Disturbance Questionnaire, Appearance Schemas Inventory-Revised, Body Image Coping Strategies Inventory, and Body Image Quality of Life Inventory. The present article reports normative data and acceptable internal reliabilities across seven completed investigations using these measures with female and male college students. Sex differences were examined and found, as expected, for most of the measures. In addition, a study evaluated an undetermined but essential psychometric property of these facets of the construct—their test–retest reliability. In a sample of 107 college students, the 2-week stability of these measures was found to be acceptable. Several directions for future research with these assessments are identified.     

小学生心理素质与学业成绩的关系

运用《瑞文标准推理测验》和自编的《小学生心理素质问卷》对1247名小学生作心理素质团体测试。利用方差分析和聚类分析,探讨小学生心理素质与学业成绩的关系。结果表明:(1)总体上,学业成绩高分组心理素质优于学业成绩中等组和低分组,学业成绩中等组优于学业成绩低分组。(2)分年级看,不同年级不同学业成绩组的小学生在心理素质因素上的差异有不同。(3)学业成绩高分组学生主要分布在心理素质较好的水平层次,学业成绩中等组主要分布在心理素质中等水平层次上,而学业成绩低分组主要分布在心理素质不好的水平层次。     

人口逆淘汰及其预防

对人口逆淘汰必须全面、动态地加以认识.必须阻止人口逆淘汰,提高人口质量,变"人口"为"人力".教育是关键措施,医疗卫生和环境改善十分重要,但决不能鼓励高学历人口多生育而限制农村人口的出生.     

An outcome management program for extending advances in choice research into choice opportunities for supported workers with severe multiple disabilities

We evaluated an outcome management program for increasing choice opportunities provided by 2 job coaches for 5 supported workers with severe multiple disabilities in a community job. The program involved specifying and monitoring behavioral outcomes among workers and staff, training staff, and supportive and corrective feedback. Increased choice provision occurred for both job coaches across a 1-year period. Results indicate how outcome management can help translate advances in choice research into routine practice.     

Dynamical concurrent schedules

Previous work on the matching law has predominantly focused on the molar effects of the contingency by examining only one reinforcer ratio for extended periods. Responses are distributed as a function of reinforcer ratios under these static conditions. But the outcome under a dynamic condition in which reinforcer ratios change continuously has not been determined. The present study implemented concurrent variable-interval schedules that changed continuously across a fixed 5-min trial. The schedules were reciprocally interlocked. The variable interval for one key changed continuously from a variable-interval 15-s to a variable-interval 480-s, while the schedule for the other key changed from a variable-interval 480-s to a variable-interval 15-s. This dynamical concurrent schedule shifted behavior in the direction of matching response ratios to reinforcer ratios. Sensitivities derived from the generalized matching law were approximately 0.62, the mean absolute bias was approximately 0.11, and r2s were approximately 0.86. It was concluded that choice behavior can come to adapt to reinforcer ratios that change continuously over a relatively short time and that this change does not require extensive experience with a fixed reinforcer ratio. The results were seen as supportive of the view that all behavior constitutes choice.     

Behavioral and pharmacological variables affecting risky choice in rats.

The effects of manipulations of response requirement, intertrial interval (ITI), and psychoactive drugs (ethanol, phencyclidine, and d-amphetamine) on lever choice under concurrent fixed-ratio schedules were investigated in rats. Responding on the "certain' lever produced three 45-mg pellets, whereas responding on the "risky" lever produced either 15 pellets (p = .33) or no pellets (p .67). Rats earned all food during the session, which ended after 12 forced trials and 93 choice trials or 90 min, whichever occurred first. When the response requirement was increased from 1 to 16 and the ITI was 20 s, percentage of risky choice was inversely related to fixed-ratio value. When only a single response was required but the ITI was manipulated between 20 and 120 s (with maximum session duration held constant), percentage of risky choice was directly related to length of the ITI. The effects of the drugs were investigated first at an ITI of 20 s, when risky choice was low for most rats, and then at an ITI of 80 s, when risky choice was higher for most rats. Ethanol usually decreased risky choice. Phencyclidine did not usually affect risky choice when the ITI was 20 s but decreased it in half the rats when the ITI was 80 s. For d-amphetamine, the effects appeared to he related to baseline probability of risky choice; that is, low probabilities were increased and high probabilities were decreased. Although increase in risky choice as a function of the ITI is at variance with previous ITI data, it is consistent with foraging data showing that risk aversion decreases as food availability decreases. The pharmacological manipulations showed that drug effects on risky choice may be influenced by the baseline probability of risky choice, just as drug effects can be a function of baseline response rate.     

消费者产品质量知觉研究

本文探讨了品牌、产地、价格、服务及消费者的知识经验对消费者产品质量知觉的影响。结果表明：１、品牌、产地、服务对消费者的产品质量知觉有显著影响;２、消费者对名牌产品的质量知觉显著高于不知名品牌,对进口产品质量知觉显著高于国产产品,对服务好的产品质量知觉显著高于服务差的产品;３、知识经验丰富的消费者的产品质量知觉易受品牌的影响,而知识经验不足的消费者的产品质量知觉易受价格、服务的影响。     

Preference after training with differential changeover delays

Pigeons were trained on a multiple schedule in which each component consisted of concurrent variable-interval (VI) 30-s VI 60-s schedules. The two components of the multiple schedule differed only in terms of the changeover delays (COD): For one component short CODs were employed, and in the second component long CODs were used. After approximate matching was obtained in each component, probe tests involving new combinations of stimuli were presented (e.g., the VI 30-s schedule from each component) to determine how the different CODs affected preference. Despite shorter CODs producing higher changeover rates, the COD value had no systematic effect on preference on the probe trials. However, differences in reinforcement rate always produced preference for the schedule with the higher reinforcement rate. The results thus show that the the pattern of changeover behavior per se is not a critical determinant of choice in the probe-trial procedure.