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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.
In Study I measures of cortical thickness were taken in 90-day-old male and female Sprague-Dawley, Wistar, and Long-Evans rats that were born to pregnant females shipped to the laboratory in late pregnancy and that were either gonadectomized at birth or left intact. No evidence for hemispheric differences in cortical thickness was found in any of the groups. Gonadectomy resulted in increased cortical thickness in male Sprague-Dawley and Wistar rats and in small increases in thickness of the left hemisphere in Long-Evans rats, especially males. No effects of gonadectomy were found in females of any strain. The lack of the expected right-over-left difference in cortical thickness in intact males may have been due to prenatal stress caused by housing, handling, and shipping. In Study 2 measures of cortical thickness were taken in 90-day-old male and female Sprague-Dawley rats that were bred in our laboratory, but otherwise similarly treated at birth. In this second study, the expected right-over-left hemispheric difference in cortical thickness was found in intact male rats; none was found in gonadectomized males or in either of the female groups. The lack of asymmetry in gonadectomized males appeared to be due to an increase in thickness in the left hemisphere. Taken together these studies provide support for the idea that hormones of testicular origin suppress cortical enlargement in the perinatal period, particularly in the left hemisphere.  相似文献   

3.
Although therapeutic alliance is a crucial factor in face-to-face therapies, no data exist on clinicians’ attitudes towards alliance in E-therapy. The study explored clinicians’ perceived importance of alliance in E-therapy, clinicians’ confidence in their skills to develop alliance in E-therapy, and whether attitudes towards alliance in E-therapy are associated with intended E-therapy practice. Clinicians (n = 106) responded to an online survey. The majority of clinicians considered alliance to be extremely important in both face-to-face therapy and E-therapy. However, clinicians’ ratings of the importance of alliance in face-to-face therapies were significantly higher than their ratings of the importance of alliance in E-therapy. Clinicians reported less confidence in their skills to develop alliance in E-therapy than in face-to-face therapy. Intended E-therapy practice correlated with confidence in one's ability to develop alliance in E-therapy and with previous E-therapy practice.  相似文献   

4.
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   

5.
1996-2004年,中国大陆的孔子、儒学研究持续繁荣发展,在以下八个方面上,取得了新的进展: (1)儒学与世界和平; ( 2 )儒家人文精神; ( 3 )简帛儒家文献; ( 4 )儒学宗教性问题; (5)儒学与生态伦理; (6)儒学与普世伦理; (7)儒学与文化保守主义; (8)儒学与自由主义; (9)儒学与民主、人权; (10)儒学与全球化。  相似文献   

6.
Past research predicts that males will be more likely to withdraw in one-on-one interactions versus groups, whereas females will be more likely to withdraw in groups than in one-on-one interactions. Ninety-eight 10-year-old children engaged in a word generation task either in same-sex dyads or in groups. Boys completed significantly more words in groups than in dyads, whereas girls' performance was similar in the 2 social structures. Confirming the hypothesis, analyses of the dynamics of dyads and groups using time spent writing as a measure of effort demonstrated that boys withdrew more than girls in dyads, whereas girls withdrew more than boys in groups. Furthermore, in groups, girls were more likely than boys to focus on one individual. Causal explanations for sex differences in preferences for differing social structures are proposed.  相似文献   

7.
Neuroendocrine activation during stress is affected by many factors contributing to the variability of the stress response. The present study was aimed at evaluating long-term changes in hypothalamo-pituitary-adrenocortical (HPA) axis function and in hedonic behavior in adult offspring prenatally stressed by maternal food restriction, with attention on possible gender differences. Adult offspring were blood sampled via a tail artery cannula. Prenatally stressed females had significantly higher adrenal weights compared to males. Plasma ACTH levels, which rose in response to acute stress induced by handling, were significantly higher in females compared to those in males. A similar pattern was found in plasma corticosterone. The rise in ACTH levels was more pronounced in prenatally stressed rats though the rise in corticosterone failed to be modified. Corticotropin releasing hormone (CRH) and proopiomelanocortin mRNA levels in the hypothalamic paraventricular nucleus and anterior pituitary, respectively, were found to be unchanged. The present experiments failed to reveal a decrease in hedonic behavior in prenatally stressed rats. In contrast, in male offspring a tendency to a higher sucrose preference was observed. These data together with observed changes in hormone and CRH mRNA levels indicate that the gestational stress used did not result in a depression-like state in adult offspring.  相似文献   

8.
This study explored adolescents' sexual self-disclosure in real life and cyberspace, as well as gender differences of sexual self-disclosure in cyberspace. There were 115 male and 92 female adolescents who participated in this pretest and posttest survey. In general, the depth of sexual self-disclosure in real life was greater than in cyberspace, but the breadth of sexual selfdisclosure in both real life and cyberspace was equivalent. The cross-lagged panel analysis indicated that adolescents who were willing to self-disclose sexual topics in real life also selfdisclosed them more in cyberspace, and vice versa. Furthermore, sexual self-disclosure in both disclosing environments was mutually predicted by each other. The findings also indicated that cyberspace might not be a substitute channel of compensatory gratification for sexual self-disclosure in real life. As for gender differences, the breadth and depth of sexual self-disclosure in male adolescents were greater than in female adolescents, in both real life and cyberspace. Male adolescents tend to be more active in Internet sexuality than females. However, female adolescents' sexual emancipation in cyberspace is not evident in Taiwan. Possible reasons, implications, and limitations of the findings are discussed.  相似文献   

9.
Using the Meaning in Life Questionnaire (MLQ), we studied Presence and Search for meaning for 34 adult clients in psychodynamic psychotherapy. Clients completed the MLQ and Outcome Questionnaire (OQ) before intake and after every eight sessions. Variance in Presence scores was mostly attributable to clients; variance in Search scores was mostly attributable to clients and therapists. Clients initially high in Presence decreased and then increased back to initial levels; clients initially low in Presence increased and then decreased back to initial levels. Clients initially low in Search increased and then leveled off; clients initially high in Search decreased and then leveled off. In lagged cross panel analyses, when clients decreased in psychological distress during one eight-week time period, they increased in Presence during the next eight-week time period; when they increased in psychological distress during one eight-week time period, they increased in search in the next time period. Excerpts from post-therapy interviews illustrate the process of working with meaning in life in psychotherapy. Implications for practice and training are discussed.  相似文献   

10.
Neurotrophins, such as brain-derived neurotrophic factor (BDNF), are a unique family of polypeptide growth factors that influence differentiation and survival of neurons in the developing nervous system. In adults, BDNF is important in regulating synaptic plasticity and connectivity in the brain. Recently, a common single-nucleotide polymorphism in the human BDNF gene, resulting in a valine to methionine substitution in the prodomain (Val66Met), has been shown to lead to memory impairment and susceptibility to neuropsychiatric disorders. An understanding of how this naturally occurring polymorphism affects behavior, anatomy, and cognition in adults is an important first step in linking genetic alterations in the neurotrophin system to definable biological outcomes in humans. We review the recent literature linking this BDNF polymorphism to cognitive impairment in the context of in vitro and transgenic animal studies that have established BDNF’s central role in neuronal functioning in the adult brain.  相似文献   

11.
Experiment 1 compared the temporal performance of 5-year-olds, 8-year-olds and adults in a bisection task with and without referent durations (similarity vs. partition). The results showed that temporal sensitivity was lower in the partition than in the similarity condition in children, whereas it was similar in these two conditions in the adults. In addition, the 5-year-olds produced a higher bisection point value in the partition than in the similarity task. Experiment 2, which examined changes in bisection performance over the trial blocks in the partition task, revealed that the 5-year-olds' bisection performance improved over the trial blocks, whereas the performance of the older participants did not. Further analyses revealed a greater variability in the establishment of the duration criterion in young children.  相似文献   

12.
This article brings an anthropology of ethics to bear on a case of forced migration and displacement among Syrian refugee women in Jordan. The case reveals how projects of Islamic self-making in displacement become “emplacement” processes within the new state-mediated context. Syrian women in Jordan engage in Islamic self-making as part of their wider emplacement practices in two primary ways: first, operating more publicly in the material world through Islamically-inspired actions and rituals than in Syria. Second, utilizing narratives of Islamic histories to establish dignity in conditions of precarity in exile. Using two focus groups in urban Jordan and participant observation in two religion classes in a Syrian refugee camp, this article focuses on these practices of Islamic self-making that serve an important role in the projects of moral emplacement for Syrian women in the Jordanian context.  相似文献   

13.
Three experiments investigated the effects of spatial and temporal contiguity in item recognition, location judgment, and distance estimation tasks. Ss learned the locations of object names in spatial arrays, which were divided into 2 regions. The names of locations were presented during map learning so that critical pairs appeared close in space and close in time, close in space but far in time, far in space but close in time, and far in space and far in time. Names primed each other in recognition only when they were neighbors in both space and time. In contrast, the effects of spatial and temporal contiguity in priming in location judgments were additive. Finally, temporal contiguity affected estimates of Euclidean distance when locations were close together, but not when they were far apart.  相似文献   

14.
Sustained behavioral contrast in children   总被引:1,自引:1,他引:0       下载免费PDF全文
Children were exposed to a multiple schedule involving equal variable-interval schedules in each of two components and a multiple schedule involving a variable-interval schedule in one component and an extinction schedule in the other. Response rates were equal in both components when each involved a variable-interval schedule. Response rates differed in the two components of the multiple variable-interval extinction schedule. Response rates were higher in the variable-interval schedule when the accompanying schedule was extinction than when it was variable interval. The increase in response rate in the variable-interval component, simultaneous with the decrease in response rate in the extinction component, illustrated sustained behavioral contrast, and was the first evidence of this phenomenon in children.  相似文献   

15.
One of the hallmarks of the aging process is a loss of sensitivity in central neuronal receptors to agonist stimulation. This appears to be especially true in central (hippocampal, striatal) muscarinic cholinergic systems and in the striatal dopamine systems. For these two systems, any decline in their sensitivity can be of extreme importance in determining the behavioral capabilities of the organism. Decrements in the striatal dopamine system may be reflected as motor behavioral deficits, while the central cholinergic systems play a major role in the processing of memory through the activation of muscarinic receptors (mAChR). Declines in the function of these receptors appear to be at least partially responsible for the marked deterioration of cognitive function in normal aging and, more notably, in Alzheimer’s disease (AD). Previous work has indicated only minimal success in improving performance in tasks that assess memory in senescent animals or humans with pharmacological agents which enhance cholinergic functioning. The present review describes research that indicates that two of the factors involved in this decline in receptor sensitivity include: (a) decreased receptor concentrations and (b) age-related decrements in signal transduction pathways. Studies are reviewed that indicate that the oxidative neural damage that occurs via kainic acid or ionizing radiation parallel those seen in aging. It is suggested that the common mechanism that may exist among all of the age-, disease-, excitatory amino acid- or radiation-induced deficits in neuronal transmission may involve free-radical-mediated alterations in membrane integrity through lipid peroxidation.  相似文献   

16.
This study examined the concurrent and longitudinal associations between stability in bullying and victimization, and social adjustment in childhood and adolescence. Participants were 189 girls and 328 boys who were studied in primary school and in secondary school. The mean age of the participants was 11.1 years in primary school and 14.1 years in secondary school. The measures consisted of peer reported social and personal characteristics. Children who bullied in childhood and adolescence were less liked and more disliked in childhood, and more aggressive and disruptive both in childhood and adolescence, than children who bullied only in childhood or adolescence. Children who bullied or who were victimized only in childhood did not differ largely in adolescence from the children that were never bullies or victims. Children who were victimized in adolescence closely resembled those who were victimized in childhood and adolescence in terms of being liked or disliked, being nominated as a friend, and shyness. The study stresses the need to distinguish between stable and transient bullies and victims.  相似文献   

17.
以高中二年级学生为被试,探讨文理分科、不同认知方式的学生对不同体裁文章及对文章不同信息加工层次的学习效果的影响。结果表明,(1)文理分科、学生认知方式对学生阅读成绩的影响不显著;(2)从总体上看,学生对不同体裁的文章学习效果不同,对说明文的学习明显优于对散文的学习;在文章不同信息的加工层次上,学生对细节的记忆优于对结构的把握;(3)对于不同体裁的文章,学生在信息加工层次上存在差异,对散文的细节记忆好于对结构的把握,对说明文的结构把握好于对细节的记忆。  相似文献   

18.
Age-related changes in grooming activity in female Fischer-344 rats were observed in a home cage and in a novel testing chamber for 50 min. Compared to the home cage condition with brief handling treatment, excessive grooming was found in the novel situation. The amount of novelty-induced grooming of aged rats (26-28 months) was about two times that of young animals (6-8 months). This increase in novelty-induced grooming of aged animals was attributable to an increase in the number of grooming bouts, prolongation of each grooming bout, and a slight increase in the duration of licking elements. However, there were no age differences in the percentage of face washing and the duration of face-washing elements. These results are discussed in terms of behavioral aging and age-related changes in peptidergic pathways in the brain.  相似文献   

19.
Are people more prosocial in a religious context? We addressed this question through an experiment. We randomly placed participants in the control group in a neutral location (a lecture hall), and we placed participants in the experimental group in a religious location (a chapel). The participants then took part in a one‐shot three‐person public goods game, which measured participants’ degree of cooperativeness. The results showed that participants in the experimental group cooperated significantly more than did participants in the control group. Furthermore, participants’ beliefs about other participants’ cooperativeness were more positive in the experimental group than they were in the control group. Improved expectations of others partially explained the enhanced cooperation in the religious context. We found no main or interaction effect of self‐reported religiosity in the experiment.  相似文献   

20.
Transfer-appropriate processing theories differentiate between conceptual- and perceptual-priming tasks. The former are said to be influenced by the nature of processing engaged in at study, but not by changes in modality between study and test; the latter are sensitive to changes in format between study and test, but not to variations in the extent of semantic processing at study. In the present experiments, we examined the effects of divided attention and aging on priming in exemplar generation and category verification, two tasks that require access to semantic information at test. Manipulations of attention during encoding affected the extent of priming in exemplar generation, but not in category verification. Priming effects were similar in young and older adults in exemplar generation following study in both full and divided attention. Although older adults did not demonstrate priming in category verification in one experiment, no effects of age or divided attention were observed in a second experiment. In addition, priming in category verification was unaffected by varying the level of processing at encoding. However, the absence of levels-of-processing and attention effects in category verification does not signal that priming in this task has a perceptual basis; priming in category verification was insensitive to modality shifts between study and test. The implications of these findings for theories of priming and cognitive aging are considered.  相似文献   

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