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991.
In contrast to models and theories that relate adult neurogenesis with the processes of learning and memory, almost no solid hypotheses have been formulated that involve a possible neurocomputational influence of adult neurogenesis on forgetting. Based on data from a previous study that implemented a simple but complete model of the main hippocampal circuitry (Weisz & Argibay, 2009), we now test this model under different situations to better study the case of remote memories. The results of this work show that following neurogenesis, the new, ongoing memories in the hippocampus are better retained than when no neurogenesis occurs at all, while the older memories are affected (to a lesser extent) by a special type of interference that is different from interference that occurs with an increasing number of memories per se. This work adds a new point of analysis in support of the interference view that might lead to the forgetting of memories in the hippocampus as they are transferred to neocortex for long-term storage, consistent with the Complementary Learning Systems models of system-level consolidation. Attention should be directed to the specific causes of interference; the results of this work signal a type of distortion of remote memories that is produced by the birth and the growth of new processing units, which results in a subtly impoverished retrieval as new neurons become active. The proposals of this model fit well with some empirical findings that are related to the issue. In the future, as new evidence emerges, we believe that this biological process, which is largely related to learning and memory, will also help to shape our ideas about normal forgetting and its possible contributions to system consolidation. 相似文献
992.
STEVEN R. LÓPEZ PH.D. JORGE I. RAMÍREZ GARCÍA PH.D. † JODIE B. ULLMAN PH.D. ‡ ALEX KOPELOWICZ M.D. § JANIS JENKINS PH.D. ¶ NICHOLAS J. K. BREITBORDE PH.D. PERLA PLACENCIA M.S.W. 《Family process》2009,48(2):179-194
We examined the distribution of expressed emotion (EE) and its indices in a sample of 224 family caregivers of individuals with schizophrenia pooled from 5 studies, 3 reflecting a contemporary sample of Mexican Americans (MA 2000, N =126), 1 of an earlier study of Mexican Americans (MA 1980, N =44), and the other of an earlier study of Anglo Americans (AA, N =54). Chi-square and path analyses revealed no significant differences between the 2 MA samples in rates of high EE, critical comments, hostility, and emotional over-involvement (EOI). Only caregiver warmth differed for the 2 MA samples; MA 1980 had higher warmth than MA 2000. Significant differences were consistently found between the combined MA samples and the AA sample; AAs had higher rates of high EE, more critical comments, less warmth, less EOI, and a high EE profile comprised more of criticism/hostility. We also examined the relationship of proxy measures of acculturation among the MA 2000 sample. The findings support and extend Jenkins' earlier observations regarding the cultural variability of EE for Mexican Americans. Implications are discussed regarding the cross-cultural measurement of EE and the focus of family interventions. 相似文献
993.
Paula I. Martin Margaret A. Naeser Michael Ho Karl W. Doron Jacquie Kurland Jerome Kaplan Yunyan Wang Marjorie Nicholas Errol H. Baker Felipe Fregni Alvaro Pascual-Leone 《Brain and language》2009,111(1):20-35
Two chronic, nonfluent aphasia patients participated in overt naming fMRI scans, pre- and post-a series of repetitive transcranial magnetic stimulation (rTMS) treatments as part of a TMS study to improve naming. Each patient received 10, 1-Hz rTMS treatments to suppress a part of R pars triangularis. P1 was a ‘good responder’ with improved naming and phrase length; P2 was a ‘poor responder’ without improved naming.Pre-TMS (10 years poststroke), P1 had significant activation in R and L sensorimotor cortex, R IFG, and in both L and R SMA during overt naming fMRI (28% pictures named). At 3 mo. post-TMS (42% named), P1 showed continued activation in R and L sensorimotor cortex, R IFG, and in R and L SMA. At 16 mo. post-TMS (58% named), he also showed significant activation in R and L sensorimotor cortex mouth and R IFG. He now showed a significant increase in activation in the L SMA compared to pre-TMS and at 3 mo. post-TMS (p < .02; p < .05, respectively). At 16 mo. there was also greater activation in L than R SMA (p < .08). At 46 mo. post-TMS (42% named), this new LH pattern of activation continued. He improved on the Boston Naming Test from 11 pictures named pre-TMS, to scores ranging from 14 to 18 pictures, post-TMS (2–43 mo. post-TMS). His longest phrase length (Cookie Theft picture) improved from three words pre-TMS, to 5–6 words post-TMS.Pre-TMS (1.5 years poststroke), P2 had significant activation in R IFG (3% pictures named). At 3 and 6 mo. post-TMS, there was no longer significant activation in R IFG, but significant activation was present in R sensorimotor cortex. On all three fMRI scans, P2 had significant activation in both the L and R SMA. There was no new, lasting perilesional LH activation across sessions for this patient. Over time, there was little or no change in his activation. His naming remained only at 1–2 pictures during all three fMRI scans. His BNT score and longest phrase length remained at one word, post-TMS.Lesion site may play a role in each patient’s fMRI activation pattern and response to TMS treatment. P2, the poor responder, had an atypical frontal lesion in the L motor and premotor cortex that extended high, near brain vertex, with deep white matter lesion near L SMA. P2 also had frontal lesion in the posterior middle frontal gyrus, an area important for naming (Duffau et al., 2003); P1 did not. Additionally, P2 had lesion inferior and posterior to Wernicke’s area, in parts of BA 21 and 37, whereas P1 did not.The fMRI data of our patient who had good response following TMS support the notion that restoration of the LH language network is linked in part, to better recovery of naming and phrase length in nonfluent aphasia. 相似文献
994.
D. Lance Ferris Douglas J. Brown Daniel Heller 《Organizational behavior and human decision processes》2009,108(2):279-286
Drawing upon belongingness theory, we tested organization-based self-esteem (OBSE) as a mediator of the relation between organizational supports and organizational deviance. Data from 237 employees were collected at three points in time over one year. Using structural equation modeling, we found that OBSE fully mediated the relation between organizational supports and organizational deviance. Controlling for preexisting predictors of deviance, including personality traits (agreeableness, neuroticism and conscientiousness) and role stressors (role conflict, ambiguity, and overload), did not eliminate the relation between OBSE and organizational deviance. The implications for the OBSE and deviance literatures are discussed. 相似文献
995.
996.
The authors conducted a cross-cultural longitudinal investigation of the effects of culture (individualism-collectivism dichotomy) on group characteristics (functional heterogeneity, preference for teamwork, group potency, outcome expectation) and on performance of 83 work groups performing 2 decision-making tasks over a 15-week period. The individualists (U.S. students) reported higher levels of functional heterogeneity and group potency and attained higher levels of group performance than did the collectivists (Korean students). In addition, culture and time interacted to influence ratings of group potency and outcome expectation. The difference in ratings of group potency between individualists and collectivists increased over time. Outcome expectation was greater among the collectivists in Time 1 and among the individualists in Time 2. The authors discuss implications for future cross-cultural group research and international management. 相似文献
997.
Brown LJ 《The Psychoanalytic quarterly》2002,71(2):273-300
The Oedipus complex is typically thought to begin in the phallic phase, when the child's relationship to the parents as a couple achieves central prominence. In contrast, the author views the appearance of oedipal conflicts in the phallic phase as the end point of a line of development of triangular relatedness that began in infancy. An aspect of the Kleinian view of the oedipal situation--that awareness of the parents as a couple begins in the preoedipal period--deserves serious consideration. A patient is presented for whom the working through of early oedipal issues in the transference-counter-transference permitted recovery from withdrawal into a fantasy world. 相似文献
998.
Joshua Fogel Steven M Albert Freya Schnabel Beth Ann Ditkoff Alfred I Neugut 《Health psychology》2002,21(4):398-404
Many Web sites offer information to breast cancer patients, who are increasingly using these sites. The authors investigated the potential psychological benefits of Internet use for medical information by breast cancer patients. Of the 251 women approached, 188 were successfully interviewed (74.9%). Forty-two percent used the Internet for medical information related to breast health issues and did so for an average of 0.80 hr per week. The Interpersonal Support Evaluation List and the UCLA Loneliness Scale, with results controlled for covariates, showed that Internet use for breast health issues was associated with greater social support and less loneliness than Internet use for other purposes or nonuse. Breast cancer patients may obtain these psychological benefits with only a minimal weekly time commitment. 相似文献
999.
We examine the hypothesis that the efficiency of executive control processes is less stable over time in older than younger adults. An age-related decrease in the efficiency of executive control should result in an increase in performance variability in task conditions requiring the recruitment of executive control processes and not in task conditions requiring minimal involvement of executive control. Performance variability was similar for younger and older adults in task conditions requiring minimal executive control and greater for older than younger adults in task conditions requiring executive control. These and other data are consistent with the proposal that aging is associated with a decrease in the stability of executive control over time. 相似文献
1000.
The relationship between personality,anger expression,and perceived family control among incarcerated male juveniles 总被引:1,自引:0,他引:1
The literature suggests that a multitude of psychological and social factors can interact to place adolescents at risk for aggression and violence. This study examined three of these factors: personality, affect, and family. Using a heterogeneous sample of male adolescents at risk for violence, a hierarchical, agglomerative cluster analysis was conducted to categorize these adolescents in terms of personality characteristics. Results of the analysis suggested three clusters of at-risk adolescents. Examination of the three cluster types found distinctions between groups on anger expression, trait anger, and trait anxiety, but not family control. It was concluded that, among male delinquents, elevated psychopathology is associated with higher anger and anxiety, but not higher family control. 相似文献