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1.
Rats were trained in four different learning tasks including the Morris-water task, a T-maze delayed nonmatch-to-sample task, a skilled unilateral reaching task, and a skilled bilateral string-pulling task. At the end of training the brains were harvested and stained using a Golgi-Cox procedure. Learning the spatial navigation task produced increased dendritic length and branching as well as decreased spine density in layer III pyramidal cells in occipital cortex. Learning the T-maze task increased dendritic branching in layer III medial but not orbital frontal cortex pyramidal cells and increased spine density in both regions. The motor learning tasks produced increased dendritic length and branching in layer V pyramidal cells in the forelimb cortex in the hemisphere contralateral to the trained limb in the unilateral skilled reaching task and in both limbs in the bilateral skilled pulling task. There were no changes in spine density in layer V in the motor tasks, but there was a decrease in spine density in layer III in the unilateral reaching task. Spatial and motor learning thus produce different patterns of change in layer III cortical pyramidal neurons. Furthermore, changes in spine density and dendritic length and branching are not tightly correlated and can increase and/or decrease independently of one another in learning tasks.  相似文献   

2.
The effects of the ACTH (4-10) analogue, ACTH (4-7)-Pro-Gly-Pro, and delta-sleep inducing peptide (DSIP) on the induction of Fos immunoreactivity in the hypothalamic parvocellular paraventricular nucleus (pPVN) and limbic brain regions were studied in Wistar rats with high (resistant) or low (predisposed) resistance to emotional stress, predicted from differences in their open-field behaviour. Fos-immunoreactive (Fos-IR) cells were counted in brain sections automatically with a computer-based image analyser. Under basal conditions, Fos-IR cell numbers were greater in the pPVN in the predisposed rats, but were lower than in the resistant rats in the basolateral amygdala and medial and lateral septum. Intraperitoneal DSIP injection (30 μg/kg) increased basal Fos-IR cell number in the pPVN and lateral septum in resistant rats, with no effects in predisposed rats. ACTH (4-10) analogue (50 μg/kg)increased Fos expression in the pPVN in both resistant and predisposed rats, with essentially no effects in the basolateral amygdala or medial and lateral septum. Emotional stress (60 min restraint and intermittent subcutaneous electrical shocks) increased Fos expression in the pPVN and medial and lateral septum similarly in predisposed and resistant rats, but in the basolateral amygdala in only the predisposed rats. Intraperitoneal DSIP injection reduced the increases in Fos-IR cell number after emotional stress, particularly in predisposed rats. In predisposed rats DSIP decreased the number of Fos-IR cells in the pPVN and the medial and lateral septum, with no change in the basolateral amygdala. In resistant rats, DSIP decreased Fos expression only in the lateral septum. ACTH (4-10) analogue injection inhibited stress-induced Fos expression in the pPVN and the medial septum, but only in predisposed rats. The experiments indicate that DSIP and ACTH (4-10) analogue reduce pPVN and limbic neurone responses to emotional stress in the rats predisposed to emotional stress; the effects on Fos expression may play a role in the biological activities of these peptides.  相似文献   

3.
沈健 《现代哲学》2006,(2):90-94
文章从符号学角度,通过《诗》《易》比较,论述了《周易》的类艺术特征。在构成符号的综合性上,在篇章的结构、句式词语的使用上,在物象选择与深层意蕴上,《易》和《诗》具有异质同构的关系。后世艺术作品中出现的同类意象,其原型可溯到《诗》,更可求诸《易》。  相似文献   

4.
Male and female Long-Evans hooded rats were placed in the complex environments for 3 months either at weaning (22 days), in young adulthood (120 days), or in senescence (24 months). The dendritic morphology of both the apical and basilar fields of layer III pyramidal cells was analyzed in both parietal and visual cortex. There were two novel results. First, although spine density was increased significantly with complex-housing in adulthood, it was decreased significantly by the same housing during development. Second, dendritic length was increased in both parietal and occipital cortex at all ages in males and was increased in adult females as well, but juvenile females showed no change in dendritic length in the occipital cortex and only a small effect on the apical field in parietal cortex. Thus, there are qualitative differences in the changes in spine density at different ages and the dendritic changes in response to complex versus isolated housing vary with sex, and in females, the changes vary with age as well. These results may explain some of the apparent inconsistencies in reports of spine and dendrite changes in the literature.  相似文献   

5.
We investigated the psychological reality of the concept of orthographical depth and its influence on visual word recognition by examining naming performance in Hebrew, English, and Serbo-Croatian. We ran three sets of experiments in which we used native speakers and identical experimental methods in each language. Experiment 1 revealed that the lexical status of the stimulus (high-frequency words, low-frequency words, and nonwords) significantly affected naming in Hebrew (the deepest of the three orthographies). This effect was only moderate in English and nonsignificant in Serbo-Croatian (the shallowest of the three orthographies). Moreover, only in Hebrew did lexical status have similar effects on naming and lexical decision performance. Experiment 2 revealed that semantic priming effects in naming were larger in Hebrew than in English and completely absent in Serbo-Croatian. Experiment 3 revealed that a large proportion of nonlexical tokens (nonwords) in the stimulus list affects naming words in Hebrew and in English, but not in Serbo-Croatian. These results were interpreted as strong support for the orthographical depth hypothesis and suggest, in general, that in shallow orthographies phonology is generated directly from print, whereas in deep orthographies phonology is derived from the internal lexicon.  相似文献   

6.
Investigation of the amnesic disorder Korsakoff Syndrome (KS) has been vital in elucidating the critical brain regions involved in learning and memory. Although the thalamus and mammillary bodies are the primary sites of neuropathology in KS, functional deactivation of the hippocampus and certain cortical regions also contributes to the chronic cognitive dysfunction reported in KS. The rodent pyrithiamine-induced thiamine deficiency (PTD) model has been used to study the extent of hippocampal and cortical neuroadaptations in KS. In the PTD model, the hippocampus, frontal and retrosplenial cortical regions display loss of cholinergic innervation, decreases in behaviorally stimulated acetylcholine release and reductions in neurotrophins. While PTD treatment results in significant impairment in measures of spatial learning and memory, other cognitive processes are left intact and may be recruited to improve cognitive outcome. In addition, behavioral recovery can be stimulated in the PTD model by increasing acetylcholine levels in the medial septum, hippocampus and frontal cortex, but not in the retrosplenial cortex. These data indicate that although the hippocampus and frontal cortex are involved in the pathogenesis of KS, these regions retain neuroplasticity and may be critical targets for improving cognitive outcome in KS.  相似文献   

7.
The present study examined expression of the immediate-early gene, c-Fos, following acquisition, 48-h (recent) recall, and 1-week (remote) recall of a socially transmitted food preference (STFP) in multiple brain regions implicated in learning and memory. In comparisons with controls, trained Long-Evans rats had increased Fos immunoreactivity in the ventral hippocampus following acquisition and recent recall. In the parahippocampal cortices, Fos was increased in the lateral entorhinal cortex after acquisition. In the orbitofrontal cortex, increased Fos immunoreactivity was observed in the lateral orbital cortex following both recent and remote recall and in the ventral orbital cortex following remote recall, indicating a role for the orbitofrontal cortex in the remote recall of STFP memory. In contrast, in the medial prefrontal cortex, increased Fos-ir was found following acquisition in the prelimbic cortex and following recent recall in the prelimbic and infralimbic cortices. No differences in Fos expression were found between trained rats and controls in the dorsal hippocampus, posterior parietal cortex, or amygdala. The present findings support a time-limited role of the hippocampus in the acquisition and recall of STFP memory and implicate neocortical regions involved in STFP acquisition, recent, and remote recall.  相似文献   

8.
800 students in Grades 9 and 11 of schools in the Central Region of the Limpopo Province of South Africa completed the Study Orientation Questionnaire in Mathematics. Mean age in Grade 11 was 17.5 yr. (SD = 1.4) and in Grade 9 15.1 yr. (SD = 1.2). Intervention was aimed at teachers and students in this group. Teachers in the trained group received training in a problem-based approach to teaching and learning in mathematics and introduced these principles into their classes. Analysis of variance on the differences between post- and pretest scores of the six subscales and the marks in mathematics and English yielded no effects for grade, sex, or grade after 6 mo. Pearson correlations for students in Grade 11 were positive between study orientation and achievement in mathematics. Improving teachers' training and expertise, transforming disadvantaged learning environments, and developing necessary formal and informal mathematical knowledge seem both essential and difficult.  相似文献   

9.
Psychologists are in a unique position to assist individuals and groups in the world who have survived torture and war trauma. Symptoms of posttraumatic stress disorder and other psychological diagnoses can be treated effectively by mental health professionals and trained lay counselors in the smallest of communities in the world. This article proposes a model for the treatment of survivors of torture and war trauma. This model has been designed to be useful to mental health professionals and to lay individuals in communities who constitute the front line in treatment: health providers, midwives, ministers, and teachers. The model is presented through examples of its use in the training of mental health counselors in the United States and in the training of promotores (health promoters) and comodrones (midwives) in Guatemala.  相似文献   

10.
11.
Pavlov in Spain     
Reflexology has been present throughout Spanish science since the last third of the nineteenth century and its importance can be seen in the works of authors such as Martín Salazar, Ramón y Cajal, Gómez Oca?a, Simarro and Turró. The most important research in Reflexology in Spain takes place a) at the Schools of Neurophysiology and Psychology in Barcelona and Madrid, b) with a group of authors specializing in pathological medicine and c) in the Military's Health Department, Pavlov's work was received in Spain with special interest. Fernández-Espa?a, who could be considered the "first Spanish Pavlovian," emphasized Pavlov's work in a series dedicated to the study of objective psychology which was published between 1914 and 1924. Planelles was the first investigator to develop a program in pavlovian experimentation, presenting his results in 1935. The Civil War (1936-1939) ended these and many other Spanish projects in psychology. After the war, interest in Reflexology and Pavlov's theories slowly rose again, first through psychosomatic medicine and then in the 60's because of the works of such authors as Monserrat-Esteve, Rof Carballo and Colodrón. The progressive inclusion of psychology in the Schools of Philosophy and Arts after 1968 marked the beginning of a new era.  相似文献   

12.
The self as a psychological construct, and the self in relation to the other has been discussed in psychological and sociological literature for decades, but not much attention has been given to the psychological development of the self in relation to the social construction of prejudice. The primary aim of this article is to explore the self in prejudice and thus the psychological processes involved in the development of self within the social context. Consequently, the aim is to explore the self in the construction and expression of prejudice from both a social and psychological approach, and to explain selfhood influences at the individual, group and community levels. I use the conceptual framework of Kohut's self psychology as a lens to present the development of the self and thus the idea of the development of the self in relation to the other. In such exploration of self in prejudice, I present some of my ideas which include prejudice as an outcome of self-definition in the context of the other, as well as linking self in prejudice and group dynamics to attachment theory and the notion of “selfgroup’ in terms of overidentification with the in-group. While the social and the psychological in terms of the development of the self cannot be separated, I have therefore attempted to merge at some point the two bodies of thought in relation to the self in prejudice.  相似文献   

13.
Kinematic adaptations in multijoint rhythmic drawing movements were investigated under unexpected perturbations in friction levels between stylus and writing surface. Changes in coupling and stability properties were assessed as a function of practice level by applying perturbations to subjects' dominant and nondominant limbs. Under nonperturbation and perturbation conditions, joint motions of right-handed subjects were highly coupled in the nondominant limb and uncoupled in the dominant limb. Stability analyses of the kinematic responses in the phase plane showed a relatively higher intrajoint resistance to perturbations in the nondominant limb as compared to the dominant limb for the elbow joint. indicating a decrease in global joint stiffness with practice. These changes in joint coupling and stiffness with practice were not observed for left-handed subjects. In addition, the stability to perturbations in the end-effector (stylus) kinematics was related to the amount of joint coupling in the nondominant limb, whereas in the dominant limb there existed no such coupling. It was concluded that (a) practice changes the responses to perturbations from anatomically specific early in practice to task-specific late in practice, and (b) this shift is related to the stability in the joint phase-plane dynamics, degree of coupling between joint angles, and the decoupling of the dynamics in the intrinsic and extrinsic control spaces.  相似文献   

14.
15.
This study evaluated the responses of vasopressin (AVP) and oxytocin (OT) neurons to alterations in hypothalamo-pituitary axis activity by adrenalectomy (ADX) or after restraint stress compared with basal conditions. Wistar male rats were perfuse-fixed by cardiac perfusion under anesthesia 3 h, 1, 3 and 14 days after ADX or Sham surgery. Coronal hypothalamic sections were used for evaluation of Fos, AVP and OT expression by immunohistochemistry. Under basal conditions and after stress, Fos-AVP double labeling showed no difference in the magnocellular subdivisions of the paraventricular nuclei (PVN) or in the supraoptic nuclei (SON), suggesting that the magnocellular AVP system is unlikely to contribute to ACTH secretion after restraint in both Sham and ADX rats. Fos-AVP double labeling in the parvocellular medial paraventricular nucleus (PaMP) in ADX groups was increased after 3 h in basal conditions, and in all periods after restraint stress. There were no differences between Sham and ADX groups in Fos-OT double labeling in any subdivision of the PVN; however, in the SON, the number of Fos-OT double labeled cells was increased at all time-points after stress in the ADX group. Fos expression was increased in the PaMP after 3 h and after restraint stress in the Sham and ADX groups, especially in the ADX group. In conclusion, Fos expression in different cell populations of the PVN can be differentially regulated by short- and long-term absence of glucocorticoid negative feedback and also by stress-related excitatory and/or inhibitory neural inputs. The Fos-AVP double labeling findings in the PaMP also indicate a minor participation of these vasopressinergic neurons in the regulation of the HPA axis after ADX.  相似文献   

16.
In this paper we analyse how the risks associated with research on transgenic plants are regulated in Sweden. The paper outlines the way in which pilot projects in the plant sciences are overseen in Sweden, and discusses the international and national background to the current regulatory system. The historical, and hitherto unexplored, reasons for the evolution of current administrative and legislative procedures in plant science are of particular interest. Specifically, we discuss similarities and differences in the regulation of medicine and plant science, and we examine the tendency towards dichotomizing risk — focusing on social/ethical risks in medicine and biological risks in plant science. The context of this article is the Synpraxia research project, an inter-disciplinary program combining expertise in sciences and the humanities.  相似文献   

17.
We assessed the relationship between brain structure and function in 10 individuals with specific language impairment (SLI), compared to six unaffected siblings, and 16 unrelated control participants with typical language. Voxel-based morphometry indicated that grey matter in the SLI group, relative to controls, was increased in the left inferior frontal cortex and decreased in the right caudate nucleus and superior temporal cortex bilaterally. The unaffected siblings also showed reduced grey matter in the caudate nucleus relative to controls. In an auditory covert naming task, the SLI group showed reduced activation in the left inferior frontal cortex, right putamen, and in the superior temporal cortex bilaterally. Despite spatially coincident structural and functional abnormalities in frontal and temporal areas, the relationships between structure and function in these regions were different. These findings suggest multiple structural and functional abnormalities in SLI that are differently associated with receptive and expressive language processing.  相似文献   

18.
Using the conceptual framework proposed by Susan Sered and institutional gender theories, this article analyses the relationship between the symbolic and idealised image of femininity with which Catholic women working in the organisations of the Roman Catholic Church in Poland identify themselves and practices of femininity in the structures of Church institutions. I locate the difficulties experienced by women in the Church in realising this symbolic image of femininity. At the same time, I identify the strategies taken by women as ways of dealing with the difficulties and as practices of achieving normative femininity in unfavourable circumstances. I analyse three types of strategies: sacralising difficulties and experienced barriers, familiarising relationships in the Church, and affirming femininity. The article examines the content of interviews conducted between 2012 and 2015 with 31 laywomen working in Church organisations in 15 dioceses in Poland and in the Episcopal Conference, who held three types of positions: office workers/secretaries, professionals, and directors.  相似文献   

19.
This study investigated developmental differences in some metacognitive variables in ill-defined problem solving and their possible connections with cognitive development in adulthood. Participants were 57 individuals of different ages (adolescents, young adults, mature adults and older adults). They solved one well-defined and six ill-defined problems while their thinking-aloud was taped. They then answered a metacognitive statements questionnaire. Differences in performance were statistically significant in all problems: the best results in interpolation and divergent production problems were achieved by the younger adult group and the best performance on most dialectical everyday problems was found in the mature adults' group. We found no significant differences between age groups in the on-line monitoring of the solving process. Accuracy in metacognitive statements was however significantly better in the mature adult and the younger adult groups. Awareness of and reflection on one's own mental processes showed a similar developmental pattern to relativistic/dialectical thought: low expression in adolescence, an increase in early adulthood, a peak in mature adulthood and a minor decline in later years.  相似文献   

20.
中学生价值观、自我概念与生活满意度的关系研究   总被引:33,自引:0,他引:33       下载免费PDF全文
用问卷法对7省市958名中学生的价值观、自我概念与生活满意度进行研究,结果表明:(1)中学生具有较高的总体生活满意度;(2)男生在身心状况和学习状况两领域的满意度显著高于女生;高一学生在物质生活领域的满意度显著高于其他三个年级,在社会适应与社会支持领域的满意度显著高于高二,在学习状况领域的满意度显著高于初三,在社会发展与国际政治领域的满意度显著高于高三;(3)价值观中的金钱权力、法律规范家庭价值取向和自我概念各因子对物质生活满意度具有显著的预测作用;价值观中的法律规范价值取向和自我概念中的人际关系自我、学习能力自我和外貌自我对身心状况满意度具有显著的预测作用;价值观中的法律规范、家庭价值取向和自我概念中的人际关系自我、学习能力自我和外貌自我对社会适应与社会支持满意度具有显著的预测作用;价值观中的金钱权力、法律规范、家庭价值取向和自我概念中的理想自我、人际关系自我、学习能力自我对学习状况满意度具有显著的预测作用;价值观中的金钱权力、法律规范、家庭、公共利益价值取向和自我概念中的学习能力自我对社会发展与国际政治满意度具有显著的预测作用.  相似文献   

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