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981.
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   
982.
通过论述海德格尔提出的"真理问题的形而上学"及范畴问题的三个视域,本文探讨了1912至1916年间,海德格尔是如何让逻辑重新获得哲学上的意义的,即如何通过确定真理的存在重新在逻辑与存在之间建立起关联的.  相似文献   
983.
Most evidence for the role of regular inflection as a default operation comes from languages that confound the morphological properties of regular and irregular forms with their phonological characteristics. For instance, regular plurals tend to faithfully preserve the base's phonology (e.g., rat-rats), whereas irregular nouns tend to alter it (e.g., mouse-mice). The distinction between regular and irregular inflection may thus be an epiphenomenon of phonological faithfulness. In Hebrew noun inflection, however, morphological regularity and phonological faithfulness can be distinguished: Nouns whose stems change in the plural may take either a regular or an irregular suffix, and nouns whose stems are preserved in the plural may take either a regular or an irregular suffix. We use this dissociation to examine two hallmarks of default inflection: its lack of dependence on analogies from similar regular nouns, and its application to nonroots such as names. We show that these hallmarks of regularity may be found whether or not the plural form preserves the stem faithfully: People apply the regular suffix to novel nouns that do not resemble existing nouns and to names that sound like irregular nouns, regardless of whether the stem is ordinarily preserved in the plural of that family of nouns. Moreover, when they pluralize names (e.g., the Barak-Barakim), they do not apply the stem changes that are found in their homophonous nouns (e.g., barak-brakim lightning), replicating an effect found in English and German. These findings show that the distinction between regular and irregular phenomena cannot be reduced to differences in the kinds of phonological changes associated with those phenomena in English. Instead, regularity and irregularity must be distinguished in terms of the kinds of mental computations that effect them: symbolic operations versus memorized idiosyncrasies. A corollary is that complex words are not generally dichotomizable as regular or irregular different aspects of a word may be regular or irregular depending on whether they violate the rule for that aspect and hence must be stored in memory.  相似文献   
984.
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   
985.
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   
986.
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   
987.
In this study, we investigated the Five-factor model in the concurrent prediction of positive symptom schizotypy as measured by the Magical Ideation (Eckblad & Chapman, 1983) and Perceptual Aberration (Chapman, Chapman, & Raulin, 1978) scales and negative symptom schizotypy as measured by the Physical Anhedonia (Chapman, Chapman, & Raulin, 1976) and Revised Social Anhedonia (Eckblad, Chapman, Chapman, & Mishlove, 1982; Mishlove & Chapman, 1985) scales. Previous studies suggest that these measures reflect the core symptoms found in schizotypal and schizoid personality disorder (Bailey, West, Widiger, & Freiman, 1993). Negative symptoms were significantly predicted by Neuroticism (+), Extraversion (-), Openness (-), and Agreeableness (-) domains of the Revised NEO Personality Inventory (NEO-PI-R; Costa & McCrae, 1992). Additionally, positive symptoms were significantly predicted by Neuroticism (+), Openness (+), and Agreeableness (-). In addition, we examined the validity of lower order traits in de- scribing these symptoms of character pathology. These findings lend further support for the use of domain and facet scales of the NEO-PI-R in the identification of personality pathology.  相似文献   
988.
The authors investigated the effect of aging on flashbulb (FB) memories. In 1996, elderly Turks recalled how they had heard about 2 remote events--the death of the first president of Turkey (in 1938) and another event involving a change in the national borders of the country (in 1939)--and both elderly and younger adults recalled how they heard about the recent death of the 8th president of Turkey (in 1993). Seventy percent of the elderly had FB memories for the 1938 death; critical variables for the formation of FB memories were personal importance attached to the event and rehearsal. Ninety percent of younger Turks and 72% of elderly Turks had FB memories for the 1993 death; the only variable that differed between the 2 groups was rehearsal.  相似文献   
989.
The Serial Color-Word Test was administered to nonclinical volunteers of three age strata (17-29, 30-45, 46-65 yr.). Sex differences on the 17 variables of the test were explored for each age stratum. Only six significant intersex differences were found. In all age strata women scored significantly higher on linear regression of reading times in one of the last two subtests, i.e., R4 or R5.  相似文献   
990.
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   
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