叶笃正院士坚持科学精神的一桩往事

今年年初,中国科学院院士叶笃正被授予我国国家最高科学技术奖。国内主流媒体纷纷报道了叶老的辉煌业绩和大家风范。这使我想起2000年才知道的叶老的一桩往事。为核实此事,我在当年7 月拜访了叶老。事情发生在1987年。当时,出生于1916年的叶老已从中国科学院副院长的职位上退了下来,但还担任着《中国科学》杂志主编的职务。     

组织职业生涯管理对职业承诺和工作满意度的影响 ——职业延迟满足的中介作用分析

以321名企业员工为被试,通过自编的职业延迟满足问卷,考察了企业员工的职业延迟满足在组织职业生涯管理对职业承诺、工作满意度影响过程中的中介作用。结果表明：职业延迟满足与组织职业生涯管理、职业承诺、工作满意度存在显著正相关;工作年限等人口统计学变量对职业延迟满足没有显著的预测作用;公平晋升、注重培训对职业延迟满足有显著的预测作用;职业延迟满足在组织职业生涯管理对职业承诺、工作满意度影响过程中存在中介作用;在结构方程模型中,职业延迟满足在公平晋升、注重培训与职业承诺、工作满意度之间存在中介作用;而职业延迟满足在职业发展与职业承诺、工作满意度之间不存在中介作用     

Neighborhood, family, and subjective socioeconomic status: How do they relate to adolescent health?

This study investigated the role of neighborhood, family, and individual subjective socioeconomic status (SES) in predicting adolescent physical health and psychological characteristics. Three hundred fifteen adolescents completed assessments of blood pressure, cortisol, and body mass index (BMI). Results revealed that lower neighborhood SES was associated with higher BMI and lower basal cortisol levels and that these effects persisted after controlling for family SES. Both family SES and neighborhood SES predicted negative psychological characteristics and experiences such as hostility and discrimination. In contrast, only subjective SES predicted positive psychological characteristics. These findings suggest the importance of understanding influences at the individual, family, and neighborhood levels for optimally targeting interventions to reduce health disparities earlier in life.     

Hypoglycemia-induced suppression of luteinizing hormone (LH) secretion in intact female rhesus macaques: role of vasopressin and endogenous opioids

The first objective of this study was to determine whether insulin-induced hypoglycemia (IIH) inhibits LH secretion in unrestrained female macaques during the follicular phase of the menstrual cycle. There was a consistent inhibitory effect of hypoglycemia on LH secretion within 3 h in these females. This inhibition was likely an indirect effect since low glucose levels did not inhibit GnRH secretion from GT1-1 neurones in vitro. We next investigated whether administration of a vasopressin antagonist (AVPa) either alone, or with naloxone could reverse the IIH-induced inhibition of LH release. Females were studied in the follicular phase during 10 h periods with blood samples collected every 10 min. Experimental groups were IIH (n=6), IIH+AVPa (n=5) and IIH+AVPa+naloxone (n=4). The first 5 h of each study served as a control and hypoglycemia was then induced with insulin. The AVPa was given as a bolus (180 microg) just before the insulin and was followed by a continuous infusion (180 microg/h) for 5 h. Naloxone (5 mg/kg) was given with the AVPa and followed by a continuous infusion (5 mg/kg/h) for 5 h. In the IIH group, LH reached its lowest value 3-4 h after insulin. Neither AVPa nor AVPa+naloxone infusion reversed the inhibitory action of hypoglycemia on LH release. These data suggest that if there are inhibitory actions of vasopressin and endogenous opioids on GnRH release induced by hypoglycemia, they are not sufficient to explain the suppression of GnRH/LH release in intact female primates.     

Patients with generalized social phobia direct their attention away from faces

The experiment tested whether patients with social phobia direct their attention to or away from faces with a range of emotional expressions. A modified dot probe paradigm (J. Abnorm. Psychol. 95 (1986) 15) measured whether participants attended more to faces or to household objects. Twenty patients with social phobia were faster in identifying the probe when it occurred in the location of the household objects, regardless of whether the facial expressions were positive, neutral, or negative. In contrast, controls did not exhibit an attentional preference. The results are in line with recent theories of social phobia that emphasize the role of reduced processing of external social cues in maintaining social anxiety.     

Ablation of cerebellar nuclei prevents H-reflex down-conditioning in rats

While studies of cerebellar involvement in learning and memory have described plasticity within the cerebellum, its role in acquisition of plasticity elsewhere in the CNS is largely unexplored. This study set out to determine whether the cerebellum is needed for acquisition of the spinal cord plasticity that underlies operantly conditioned decrease in the H-reflex, the electrical analog of the spinal stretch reflex. Rats in which the cerebellar output nuclei dentate and interpositus (DIN) had been ablated were exposed for 50 d to the H-reflex down-conditioning protocol. DIN ablation, which in itself had no significant long-term effect on H-reflex size, entirely prevented acquisition of a smaller H-reflex. Since previous studies show that corticospinal tract (CST) transection also prevents down-conditioning while transection of the rubrospinal tract and other major descending tracts does not, this result implies that DIN output that affects cortex is essential for generation of the CST activity that induces the spinal cord plasticity, which is, in turn, directly responsible for the smaller H-reflex. The result extends the role of the cerebellum in learning and memory to include participation in induction of plasticity elsewhere in the CNS, specifically in the spinal cord. The cerebellum might simply support processes in sensorimotor cortex or elsewhere that change the spinal cord, or the cerebellum itself might undergo plasticity similar to that occurring with vestibulo-ocular reflex (VOR) or eyeblink conditioning.     

The emergence of competing modules in bilingualism

How does the brain manage to store and process multiple languages without encountering massive interference and transfer? Unless we believe that bilinguals live in two totally unconnected cognitive worlds, we would expect far more transfer than actually occurs. However, imaging and lesion studies have not provided consistent evidence for the strict neuronal separation predicted by the theory of modularity. We suggest that emergentist theory offers a promising alternative. It emphasizes the competitive interplay between multiple languages during childhood and by focusing on the dual action of competition and entrenchment, avoids the need to invoke a critical period to account for age of acquisition effects in second-language learning. This view instantiates the motto formulated by Elizabeth Bates that 'modules are made, not born.'     

6～14岁儿童对想象物的文字与图画描述

本研究采用开放式问卷法,通过调查810名6-14岁儿童头脑中想象物的文字与图画描述,考察了儿童想象发展的特点。结果发现：(1)儿童对想象物的文字与图画描述可以分划分为3种水平：表象的记忆水平、表象的再造水平和表象创造水平。其中,对想象物的文字描述水平,年龄发展趋势明显,从小学一至二年级之间和四到五年级之间的发展变化最大;而对想象物的图画描述水平,年龄发展趋势不明显。(2)根据儿童对想象物的文字描述和图画描述的发展的匹配程度,可以把儿童的想象发展分为3种类型：文字与图形符号均衡发展型、文字符号型和图形符号型。     

从面孔模块到马赛克──视觉特异性加工的脑机制

“脑功能的模块性”是视觉乃至整个认知神经科学的研究热点。特异性的面孔加工模块被当作是认知模块假说的最好证据。但综述跨学科的正反两方面实验证据表明,视觉加工存在特异性,并没有普遍的模块式的亚单元,而是“马赛克”镶嵌式的组构。     

对学生学习成绩与社会行为的交叉滞后分析

采用二元交叉滞后回归分析法考察小学四、五年级学生和初中一、二年级学生在21个月中的学校适应与学习成绩之间的关系。结果发现,在同时性测量中,由教师评价获得的中小学生的社交领导能力、定向耐挫能力、果敢性社交技能得分和同伴积极提名分数与他们的学习成绩之间均存在正相关关系,而他们的攻击破坏得分、学习适应不良得分以及小学生的同伴消极提名分均与他们的学习成绩有显著的负相关关系。二元交叉滞后回归分析结果表明,小学生在前测中的社交领导能力得分、攻击破坏得分、定向耐挫得分、学习适应不良得分、果敢性社交技能得分同伴积极和消极提名得分均可以预测21个月后的学习成绩。对中学生来说,这种预测关系只在攻击破坏行为、定向耐挫行为中存在。中小学生的害羞抑制得分和焦虑抑郁得分与他们的学习成绩之间既没有同时性的相关关系,也没有滞后性的预测关系。