Contrasting effects of motor and visual spatial learning tasks on dendritic arborization and spine density in rats

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.     

1996-2004年中国大陆儒学研究的新进展

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。     

Longitudinal linkages between sibling relationships and adjustment from middle childhood through adolescence

The links between changes in sibling conflict and intimacy and changes in perceived peer social competence and depression symptoms were examined from middle childhood through adolescence. Participants were mothers, fathers and first- and second-born siblings from 197 White, working/middle class, two-parent families. Peer competence peaked in early adolescence and then declined; depression symptoms were high in middle childhood and, for girls, in middle adolescence. Controlling for parent-offspring relationships and sibling and parent adjustment, increases in sibling conflict were linked to increases in depression symptoms, and increases in sibling intimacy were linked to increases in peer competence and, for girls, decreases in depression symptoms.     

Delta-sleep inducing peptide (DSIP) and ACTH (4-10) analogue influence fos-induction in the limbic structures of the rat brain under emotional stress

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.     

Changes in meaning in life across the course of psychodynamic psychotherapy

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.     

Historical changes in cigarette smoking and smoking-related beliefs after 2 decades in a midwestern community.

Rates of cigarette smoking and smoking-related beliefs in 1980 and 2001 among 7th-11th graders in a midwestern community were compared. Smoking was less prevalent in 2001 than in 1980, with the greatest declines in experimental smoking and a smaller drop in regular smoking. Beliefs about smoking generally became more negative. Adolescents (particularly nonsmokers) viewed smoking as more addictive and as having more negative social consequences in 2001 than in 1980 and had more negative attitudes toward smoking in 2001. These results were replicated among parent-child pairs in which parents were measured when they were adolescents between 1980 and 1983 and their children were measured in 2001. These beliefs and attitudes partially mediated the effects of time on smoking.     

Achievement in mathematics in grades 9 and 11 in Limpopo Province of South Africa: introduction of a problem-based approach

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.     

Stability in Bullying and Victimization and its Association with Social Adjustment in Childhood and Adolescence

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.     

Strategies for visual word recognition and orthographical depth: a multilingual comparison

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.     

Spatial training and high-frequency stimulation engage a common pathway to enhance glutamate release in the hippocampus

We have measured depolarization-induced release of endogenous glutamate in synaptosomes prepared from the dentate gyrus after the induction of LTP by high-frequency stimulation in anesthetized rats, and after training in the water maze. Both spatial training and LTP in untrained rats were accompanied by an increase in glutamate release from dentate synaptosomes. The enhancement of synaptosomal glutamate release induced by high-frequency stimulation was abolished in well-trained rats, and was reduced in partially trained rats and in rats trained in a nonspatial task. However, the magnitude of LTP was similar in well-trained and untrained groups. These results indicate that spatial training activates a glutamate release pathway that converges with that activated in LTP, and demonstrate an unexpected dissociation between increased glutamate release and LTP.     

Gender, grade, and relationship differences in emotional closeness within adolescent friendships

Previous research has examined gender and grade differences in the emotional closeness of adolescents' same- and cross-sex friendships. However, findings from these studies have been inconsistent because they have failed to (1) differentiate between cross-sex friendships and romantic relationships and (2) compare same- and cross-sex friendships. In an attempt to clarify previous findings, gender and grade differences in adolescent reports of emotional closeness within same- and cross-sex friendships were examined in the current study. Responses from two hundred seventy adolescents indicated gender differences in reports of time spent with their friends daily and levels of relationship closeness, cohesion, and commitment. Further, grade moderated relationship differences in reports of relationship cohesion and closeness. Differences in predictors of intimacy support previous studies that have found grade and gender differences in levels of intimacy in adolescents' same- and cross-sex friendships. Results also elaborate on previous research by indicating grade differences in adolescents' perceptions of cohesion and closeness in their same- and cross-sex friendships. Findings are discussed in terms of understanding differences in adolescent reports of intimacy within same- and cross-sex friendships.     

Experience-dependent changes in dendritic arbor and spine density in neocortex vary qualitatively with age and sex

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.     

Sexual self-disclosure in Cyberspace among Taiwanese adolescents: gender differences and the interplay of Cyberspace and real life.

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.     

Divided attention, aging, and priming in exemplar generation and category verification

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.     

Bullying in elementary school, high school, and college

This study investigated the continuity in being a bully, victim, or bully-victim from elementary school through college in 119 undergraduates. Of 25 who bullied in college, 18 (72%) had been bullied in high school and elementary school. Of 26 bullies in college, 14 (53.8%) had been bullies in high school and elementary school. Of 12 bully-victims in college, 5 (41.6%) had been bully-victims in high school and elementary school. There were significant positive correlations between being a bully in college, high school, and elementary school, and being bullied in college and high school, and high school and elementary school, and between being both a bully and victim in elementary school, a bully and victim in high school, and a bully and victim in college.     

Relation of career adaptability to meaning in life and connectedness among adolescents in Hong Kong

This study examined relationships among career adaptability, meaning in life, and connectedness in Hong Kong with Chinese male and female Grade 9 students (n = 543). The results indicated that presence of meaning in life positively predicted connectedness; and in the males career concern was predicted by presence of meaning in life. Also in males, career control was predicted both by presence and search for meaning in life, while career curiosity was predicted by connectedness to school, and by presence and search for meaning in life. Career confidence was predicted by connectedness to school, and presence and search of meaning in life. In the females, career concern was predicted by presence of meaning in life and connectedness to school, but negatively by connectedness to peers. Career control and career curiosity were predicted by presence and search for meaning in life. Career confidence was predicted by presence of meaning in life. Limitations of the study are identified; and implications for future research and guidance with Chinese adolescents in schools are discussed.     

Treating survivors of war trauma and torture.

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.     

Developmental Differences in Metacognition and their Connections with Cognitive Development in Adulthood

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.     

Impaired appetitively as well as aversively motivated behaviors and learning in PDE10A-deficient mice suggest a role for striatal signaling in evaluative salience attribution

Phosphodiesterase 10A (PDE10A) hydrolyzes both cAMP and cGMP, and is a key element in the regulation of medium spiny neuron (MSN) activity in the striatum. In the present report, we investigated the effects of targeted disruption of PDE10A on spatial learning and memory as well as aversive and appetitive conditioning in C57BL/6 J mice. Because of its putative role in motivational processes and reward learning, we also determined the expression of the immediate early gene zif268 in striatum and anterior cingulate cortex. Animals showed decreased response rates in scheduled appetitive operant conditioning, as well as impaired aversive conditioning in a passive avoidance task. Morris water maze performance revealed not-motor related spatial learning and memory deficits. Anxiety and social explorative behavior was not affected in PDE10A-deficient mice. Expression of zif268 was increased in striatum and anterior cingulate cortex, which suggests alterations in the neural connections between striatum and anterior cingulate cortex in PDE10A-deficient mice. The changes in behavior and plasticity in these PDE10A-deficient mice were in accordance with the proposed role of striatal MSNs and corticostriatal connections in evaluative salience attribution.