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891.
This study has 2 objectives: (a) to explore typical paths of cognitive development associated with aging, terminal decline, and dementia and (b) to promote and illustrate an individual-oriented approach to the study of cognitive aging based on longitudinal panel data from a population-based sample (N = 500; age range-sub(T1)= 60-80, where T refers to time) tested at 3 occasions 5 years apart. Results document interindividual differences in multivariate patterns of change. Although cognitive changes generally covary, the present study indicates that subgroups of individuals develop along different paths characterized by selective changes in subsets of cognitive functions. Typical progression of dementia followed a developmental cascade from low declarative memory, via low functioning across all observed cognitive measures, to dementia diagnosis, and finally, death. 相似文献
892.
This review identified 1275 studies examining cognitive deficits in people with schizophrenia, published between 1990 and
2003. Data from 113 studies (4365 patients and 3429 controls) were combined in a meta-analysis carried out on the five cognitive
domains of IQ, memory, language, executive function, and attention. Studies were excluded where they lacked a suitable control
group or failed to present complete information. In all five cognitive domains, analysis indicated a consistent trend for
patients to perform more poorly than healthy controls, with significant heterogeneity across studies. Sources of heterogeneity
were analyzed and a need to ensure more appropriate composition of patient and control groups and to adopt a more refined
and methodologically correct, hypothesis-driven approach was identified. 相似文献
893.
Long-term social isolation of laboratory animals is a model to study the behavioral and neurochemical consequences of the absence of social interaction in rodents. Many of the symptoms induced by isolation resemble depression and anxiety disorder symptomatology. Our studies have revealed that male mice socially isolated for more than 4 weeks, exhibit increased aggressiveness, a reduced responsiveness to GABA(A) receptor acting drugs, and a downregulation of brain levels of 3alpha,5alpha-tetrahydroprogesterone (allopregnanolone: 3alpha,5alpha-THP), a neurosteroid endowed with potent positive allosteric modulatory activity of the action of GABA at various GABA(A) receptor subtypes. This downregulation of 3alpha,5alpha-THP appeared to be associated with the reduction of brain type I 5alpha-reductase mRNA and protein expression. Systemic administration of the selective serotonin reuptake inhibitor fluoxetine and its metabolite norfluoxetine normalized brain 3alpha,5alpha-THP content and reduced responsiveness to GABA(A) mimetic drugs in a stereospecific manner. These drugs in nanomolar doses also reduced social isolation-induced aggressiveness with the same stereospecificity as detected in their action on 3alpha,5alpha-THP brain content, while their ex vivo inhibition of serotonin reuptake occurred at high micromolar doses and lacked stereospecificity. From these results we infer that the brain 3alpha,5alpha-THP content physiologically upregulates GABA(A) receptor responsiveness to GABA and that social isolation induces a reduction of brain 3alpha,5alpha-THP content that is probably causally related to the onset of aggression. 相似文献
894.
Conceptual overlap and heterogeneity have long been noted as weaknesses of the Minnesota Multiphasic Personality Inventory's clinical scales. Restructured clinical (RC) scales recently were developed to address these concerns (A. Tellegen et al., 2003). The authors evaluated the psychometric properties of the RC scales in psychology clinic clients (N=285) and military veterans (N=567). The RC scales were as internally consistent as the clinical scales and correlated strongly with their original counterparts (except for RC3/Hysteria). They also were less intercorrelated, produced conceptually clearer relations with measures of personality and psychopathology, and yielded somewhat greater incremental utility than the clinical scales. Thus, the RC scales demonstrated several psychometric strengths while utilizing 60% fewer items, but the 2 sets of scales cannot be used interchangeably. Interpretive considerations are discussed. 相似文献
895.
This study tested alternative factor models of the General Health Questionnaire-12 (GHQ-12), based on previous research findings, with a large sample using confirmatory factor analysis. An alternative models framework was used to test 6 factor analytic models. A 3-factor model was the best explanation of the sample data. The 3 factors were labeled Anxiety-Depression, Social Dysfunction, and Loss of Confidence. The model was found to be factorially invariant between men and women. The utility of the 3 subscales, as opposed to the total GHQ-12 score, is questioned as they appear to provide little information beyond that of a general factor. 相似文献
896.
McConkie-Rosell A Finucane B Cronister A Abrams L Bennett RL Pettersen BJ 《Journal of genetic counseling》2005,14(4):249-270
These recommendations describe the minimum standard criteria for genetic counseling and testing of individuals and families
with fragile X syndrome, as well as carriers and potential carriers of a fragile X mutation. The original guidelines (published
in 2000) have been revised, replacing a stratified pre- and full mutation model of fragile X syndrome with one based on a
continuum of gene effects across the full spectrum of FMR1 CGG trinucleotide repeat expansion. This document reviews the molecular
genetics of fragile X syndrome, clinical phenotype (including the spectrum of premature ovarian failure and fragile X-associated
tremor-ataxia syndrome), indications for genetic testing and interpretation of results, risks of transmission, family planning
options, psychosocial issues, and references for professional and patient resources. These recommendations are the opinions
of a multicenter working group of genetic counselors with expertise in fragile X syndrome genetic counseling, and they are
based on clinical experience, review of pertinent English language articles, and reports of expert committees. These recommendations
should not be construed as dictating an exclusive course of management, nor does use of such recommendations guarantee a particular
outcome. The professional judgment of a health care provider, familiar with the facts and circumstances of a specific case,
will always supersede these recommendations. 相似文献
897.
Claes E Evers-Kiebooms G Denayer L Decruyenaere M Boogaerts A Philippe K Legius E 《Journal of genetic counseling》2005,14(5):349-363
This prospective study evaluates emotional functioning and illness representations in 68 unaffected women (34 carriers/34
noncarriers) 1 year after predictive testing for BRCA1/2 mutations when offered within a multidisciplinary approach. Carriers had higher subjective risk perception of breast cancer
than noncarriers. Carriers who did not have prophylactic oophorectomy had the highest risk perception of ovarian cancer. No
differences were found between carriers and noncarriers regarding perceived seriousness and perceived control of breast and
ovarian cancer. Mean levels of distress were within normal ranges. Only few women showed an overall pattern of clinically
elevated distress. Cancer-specific distress and state-anxiety significantly decreased in noncarriers from pre- to posttest
while general distress remained about the same. There were no significant changes in distress in the group of carriers except
for ovarian cancer distress which significantly decreased from pre- to posttest. Our study did not reveal adverse effects
of predictive testing when offered in the context of a multidisciplinary approach. 相似文献
898.
Differences in Individual Approaches: Communication in the Familial Breast Cancer Consultation and the Effect on Patient Outcomes 总被引:1,自引:0,他引:1
This multicenter study aimed to assess (i) whether individual clinical geneticists and genetic counselors vary in their communication skills and (ii) whether this variation in communication impacts on patient outcomes, such as anxiety, depression, genetics knowledge, and satisfaction. One hundred and fifty women from high-risk breast cancer families attending their first genetic counseling consultation completed pre and post-consultation self-report questionnaires. The consultations were audiotaped and transcribed verbatim. Univariate analyses showed highly significant differences between individual clinical geneticists and genetic counselors in: facilitating understanding (p 0.001); facilitating active involvement (p 0.001); facilitating partnership building (p = 0.003); addressing emotional concerns (p 0.001); and discussing prophylactic mastectomy (p = 0.017). Multivariate linear regressions showed that this variation in communication resulted in a greater change in patients depression 4 weeks after the counseling session (p = 0.017). These findings suggest clinical geneticists and genetic counselors have achieved some standardization in communicating information, but showed diversity in their facilitation skills. Communication skills may be a useful area to explore further in this field. 相似文献
899.
Evaluating Genetic Counseling: Client Expectations,Psychological Adjustment and Satisfaction with Service 总被引:1,自引:0,他引:1
Periodic evaluations of genetic counseling services are useful for determining the effectiveness of counseling in meetings its psycho-educational aims, as well as identifying where improvements to the service may be made. This study aimed to evaluate the genetic counseling services provided by Genetic Services of Western Australia (GSWA) to determine the impact of counseling on client expectations, satisfaction with the service, and psychological adjustment, defined as wellbeing and perceived personal control (PPC). A total of 122 clients participated in a self-administered survey conducted pre- and post-counseling. Client expectations of the service as a means of providing information were met, and opportunities for counselors to meet client’s expectations of psychological support were identified. Furthermore, counseling was found to maintain and enhance psychological wellbeing of clients. The role of counseling in facilitating the development of PPC was a key contributor to a high sense of satisfaction in clients. 相似文献
900.
Research that uses simple response time tasks and neuroimaging has emphasized that attentional preparation based on temporal
expectancy modulates processing at motor levels. A novel approach was taken to study whether the temporal orienting of attention
can also modulate perceptual processing. A temporal-cuing paradigm was used together with a rapid serial visual presentation
procedure, in order to maximize the processing demands of perceptual analysis. Signal detection theory was applied in order
to examine whether temporal orienting affects processes related to perceptual sensitivity or to response criterion (indexed
byďand beta measures, respectively). If temporal orienting implies perceptual preparation, we would expect to observe an increase
in perceptual sensitivity (ď) when a target appeared at expected, rather than unexpected, time intervals. Indeed, our behavioral results opened the possibility
that focusing attention on time intervals not only enhances motor processing, as has been shown by previous research, but
also might improve perceptual processing. 相似文献