Drug discrimination under concurrent variable-ratio variable-ratio schedules

Pigeons were trained to discriminate 5 mg/kg pentobarbital from saline under concurrent variable-ratio (VR) VR schedules, in which responses on the pentobarbital-biased lever were reinforced under the VR schedule with the smaller response requirements when pentobarbital was given before the session, and responses on the saline-biased key were reinforced under the VR schedule with the larger response requirements. When saline was administered before the session, the reinforcement contingencies associated with the two response keys were reversed. When responding stabilized under concurrent VR 20 VR 30, concurrent VR 10 VR 40, or concurrent VR 5 VR 50 schedules, pigeons responded almost exclusively on the key on which fewer responses were required to produce the reinforcer. When other doses of pentobarbital and other drugs were substituted for the training dose, low doses of all drugs produced responding on the saline-biased key. Higher doses of pentobarbital and chlordiazepoxide produced responding only on the pentobarbital-biased key, whereas higher doses of ethanol and phencyclidine produced responding only on this key less often. d-Amphetamine produced responding primarily on the saline-biased key. When drugs generalized to pentobarbital, the shape of the generalization curve under concurrent VR VR schedules was more often graded than quantal in shape. Thus, drug discrimination can be established under concurrent VR VR schedules, but the shapes of drug-discrimination dose-response curves under concurrent VR VR schedules more closely resemble those seen under interval schedules than those seen under fixed-ratio schedules. Graded dose-response curves under concurrent VR VR schedules may relate to probability matching and difficulty in discriminating differences in reinforcement frequency.     

Immediate-early Fos protein levels in brainstem neurons of male and female gonadectomized mice subjected to cold exposure

The expression of the immediate early gene c-fos has been used extensively as a marker for neural activation in response to acute and chronic stressful stimuli in brain and spinal cord. The present study examined the expression of Fos protein in the brainstem nuclei of male and female gonadectomized mice in response to cold stress. Free-floating sections were processed immunohistochemically for Fos protein using standard avidin-biotin complex methods. The number of Fos-positive neurons in each nucleus was determined. Although the experiment was designed to look for gender differences, results were equivalent between females and males. After mice were exposed to a cold ambient temperature (4 degrees C) for 2 h, elevated numbers of Fos-positive neurons were counted in the medullary gigantocellular reticular nucleus, medullary raphe nucleus, nucleus of the solitary tract and in locus coeruleus. However, no elevated expression was found in nucleus ambiguus, nor in neurons of the A1 group, nor the C2 or C3 group. Similar to rats, these results with mice reveal a widespread arousal system in the lower brainstem activated by cold stress in both genders. These findings in gonadectomized mice have set the stage for investigations following hormonal and genetic manipulations.     

Validation of a single-item measure of usual physical activity

The purpose of this study was to assess the reliability and validity of a single-item measure of Usual Physical Activity and to assess its usefulness as a physical activity tool for perimenopausal women. 188 perimenopausal women participated (age: M = 47 yr., SD = 3; range = 40-55). Data were collected using the Women's Health Assessment Scale, the Physical Activity Questionnaire, the Perimenopause-related Quality of Life Scale, a health history and demographic questionnaire, and the rater. Scores were stable over a 2-wk. interval. Convergent validity was supported by a correlation of .66 between ratings on Usual Physical Activity and the Physical Activity Questionnaire. Concurrent validity was supported by the association of the rating of Usual Physical Activity with three parameters of Body Mass Index, psychosomatic symptoms, and perimenopause related quality of life, known to be associated with physical activity. Highly active women had a lower Body Mass Index than less active and inactive women. Active women tended to report fewer and less distressing psychosomatic symptoms and better quality of life. These findings support the use of rating of Usual Physical Activity to classify perimenopausal women into categories of physical activity.     

"中小学生心理健康"公众观的调查和分析

本研究调查分析了家长、教师对中小学生心理健康判断标准的认识.因素分析表明,家长主要强调四个因素"精神和神经病症"、"良好品行"、"健康人格"和"循环性";教师则强调五个因素"精神分裂症状"、"神经质"、"好学生标准"、"不良人格"和"不良品行".公众对于情、意、个性及社会适应等同心理健康的关系认识较为清楚,但对认知、品行及体征与之的关系认识则片面和模糊."好学生标准"对判断有重要影响.     

Evaluating gene x psychological risk factor effects in the pathogenesis of anxiety: a new model approach

The present study evaluated the singular and interactive effects of a functional polymorphism (variation) in the serotonin transporter (5-HTT) gene and a psychological trait (anxiety sensitivity [AS], i.e., fear of arousal symptoms) in predicting subjective and physiological responses to a 35% carbon dioxide (CO2) challenge in a community sample (N = 72). Genotypes were divided into 2 groups in accord with prior research. Findings were partially supportive of the hypothesized risk model. These indicated that the Group L genotype (homozygous for the 1 allele), compared with the Group S genotype (homozygous for the s allele plus heterozygous individuals), predicted greater fearful response to the biological challenge. There was also an AS x Genotype interaction predicting heart rate variability (HRV) in response to the CO2, suggesting that high AS plus Group L status predicts decreased HRV.     

The role of inhibition in the regulation of sequential action

We investigated the regulation of sequential action using a new paradigm. Participants learned a sequence of seven stimulus categories and then monitored for them during successive displays. All displays were instances of these categories, presented in pseudorandom order. On each trial, participants monitored for an instance of Category 1, pressed a key on a computer keyboard, then monitored for an instance of Category 2, pressed a key on the keyboard, and so on for all seven categories. Thus, a perfect trial contained exactly seven responses. Intrusion errors were classified as a function of ordinal distance from the current serial position ( n ). Fewer intrusion errors were made at near serial positions than at far ones, suggesting a gradient of lateral inhibition. In addition, more intrusions were made on n + 1 categories than n − 1 categories, suggesting greater availability of intended than completed goals. In accord with current models of sequential action, the results indicate lateral and self-inhibition as important mechanisms in regulation of sequential action.     

The lexical constituency model: some implications of research on Chinese for general theories of reading

The authors examine the implications of research on Chinese for theories of reading and propose the lexical constituency model as a general framework for word reading across writing systems. Word identities are defined by 3 interlinked constituents (orthographic, phonological, and semantic). The implemented model simulates the time course of graphic, phonological, and semantic priming effects, including immediate graphic facilitation followed by graphic inhibition with simultaneous phonological facilitation, a pattern unique to the Chinese writing system. Pseudocharacter primes produced only facilitation, supporting the model's assumption that lexical thresholds determine phonological and semantic, but not graphic, effects. More generally, both universal reading processes and writing system constraints exist. Although phonology is universal, its activation process depends on how the writing system structures graphic units.     

近五十年来台湾地区士林哲学之研究与前瞻

根据祁尔松（Etienne Gilson）的说法,中世纪哲学,尤其是十三世纪的思想,是基督宗教哲学。本文按其在台湾发展时所袭用的名词,称之为士林哲学。士林哲学之传入中国,虽然早在利玛窦时期（1550—1610）已经开始,但真正成为学术思想之主流之一,是最近五十年来在台湾地区的发展。20世纪初士林哲学初传入台湾时,当时的思想环境,对基督宗教哲学并不十分友善,这种种情况,与中世纪的思想家,面对信仰与神学之挑战相似。当时的思想家,融合各种不同的思想派系,对柏拉图与亚理斯多德的观念,重新诠释与批判,批判与诠释是创新的基础。所以,中世纪可说是哲学的第二春,而中世纪哲学之精华,即全盛期的士林哲学。十四世纪唯名论之后,士林哲学逐步式微,于十九世纪末再兴。本文认为,士林哲学在台湾发展之过程,与其在中世纪之盛行,及十九世纪末之再兴,背景虽异但有不少相似之处,而这些相似之处,正是士林哲学之基本思想与立场。本文对台湾士林哲学之发展,从四方面探讨：（1）回到形上学之根以面对新的挑战;（2）形上学基本立场与概念之说明;（3）反思与批判;（4）未来发展之方向。本文所参考之资料,一是已发表之学术文献;其二是与学者们之正式交谈——如学术演讲、座谈会等,及非正式之谈话、访问等。     

执行功能中认知灵活性发展的研究进展

近十多年以来,执行功能已成为研究的热点和前沿。认知灵活性是执行功能的主要成分,它对个体能力发展和对环境适应的方面起着重要作用。该文从认知灵活性的本质、发展、研究方法及其与教育的关系进行探讨。     

青少年性发展的差异及其对人格发展的影响

研究青少年性发育现状及其对性心理与人格发展的影响。方法：采用统一编制的《中学生性现状调查问卷》及16PF人格问卷,采用分层抽样方法,对江西4所中学的1000名学生进行问卷调查。结果：(1)青少年手淫行为发生率、与异性交往愿望及性冲动等方面均存在性别差异和年级差异;(2)性成熟的青少年的多种人格特征与未成熟的存在显著性差异。结论：青少年性生理发育正常,但在性心理方面很不成熟,对手淫、性冲动和异性交往等方面问题较多,性发展影响青少年人格发展。