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281.
Neuronal models of cognitive functions   总被引:4,自引:0,他引:4  
J P Changeux  S Dehaene 《Cognition》1989,33(1-2):63-109
Understanding the neural bases of cognition has become a scientifically tractable problem, and neurally plausible models are proposed to establish a causal link between biological structure and cognitive function. To this end, levels of organization have to be defined within the functional architecture of neuronal systems. Transitions from any one of these interacting levels to the next are viewed in an evolutionary perspective. They are assumed to involve: (1) the production of multiple transient variations and (2) the selection of some of them by higher levels via the interaction with the outside world. The time-scale of these "evolutions" is expected to differ from one level to the other. In the course of development and in the adult this internal evolution is epigenetic and does not require alteration of the structure of the genome. A selective stabilization (and elimination) of synaptic connections by spontaneous and/or evoked activity in developing neuronal networks is postulated to contribute to the shaping of the adult connectivity within an envelope of genetically encoded forms. At a higher level, models of mental representations, as states of activity of defined populations of neurons, are discussed in terms of statistical physics, and their storage is viewed as a process of selection among variable and transient pre-representations. Theoretical models illustrate that cognitive functions such as short-term memory and handling of temporal sequences may be constrained by "microscopic" physical parameters. Finally, speculations are offered about plausible neuronal models and selectionist implementations of intentions.  相似文献   
282.
The roles of origin family environmental characteristics and couple consensus-building process within the development of marital relationships were examined prospectively in 16 premarital couples. Three important findings emerged. First, significant correlations were found between dimensions of origin family environment and the reported level of satisfaction within the couple's current relationship. Second, measures of the couple's ability to reach consensus concerning important interpersonal relationships appeared to be important mediators of the association between origin family environment and current relationship satisfaction. Third, important gender differences emerged that replicate and extend prior findings that portray women in the role of "relationship specialist" within their marriages. As a group, these findings were best explained by a developmental model of early marriage that envisions the young couple as facing two entwined tasks: to define both their family heritage and their new relationship identity. Overall, the importance of examining family-of-origin characteristics and consensus-building process as critical determinants of the fate of intimate relationships received strong support. The gender differences found in the literature reviewed, as well as the results of this study, have largely been overlooked by the theory and practice of family therapy. Efforts on both the research and theory construction fronts are needed to increase our understanding of the mechanisms whereby prior family experience is brought forward into current intimate relationships.  相似文献   
283.
What do celibates consider the adaptive and maladaptive aspects of their celibate religious lifestyle? What role has celibacy played in understanding the differences between those who persevere and those who choose to resign from celibate religious life and/or ordained ministry? Using data from extensive interviews, this exploratory study begins to focus some of the perceived effects of celibacy upon personal development for both those who persevere in celibate religious life and those who resign.  相似文献   
284.
Topographic electroencephalographic alpha in recovered depressed elderly   总被引:1,自引:0,他引:1  
Late-middle-aged and elderly normal volunteers with past histories of Major Depression according to the Diagnostic and Statistical Manual of Mental Disorders (third edition-revised) criteria were compared with sex- and age-matched control subjects using topographic electroencephalographic (EEG) indices. Healthy, euthymic recovered depressed subjects showed greater alpha amplitudes than controls. Delta, theta, and beta amplitudes did not reliably distinguish the groups. Considered in the context of previous research indicating that actively depressed subjects exhibit elevated EEG alpha compared to controls, these findings raise questions concerning state and trait conceptualizations of depression and EEG alpha.  相似文献   
285.
Shavelson's hierarchical, multifaceted self-concept model (HMFM) has proven useful to educational and psychological researchers. The reliability and factorial validity of a well-known HMFM instrument - the Fleming-Courtney Self-Rating Scales (SRS) - were examined for a sample of 198 Filipino college students. Confirmatory factor analysis compared six structural models. A six-factor, oblique model that included two social factors (Social Acceptance and Social Anxiety) fit the data best, and a second-order factor analysis supported the hierarchical structure of the SRS. The men were significantly higher than the women on three self-concept scales, but the only large effect was for Physical Abilities, consistent with findings in a U.S. college sample. Results provided some support for the utility of both the SRS and HMFM for Filipinos.  相似文献   
286.
The study attempted to replicate and extend the results of an earlier study by Wild and Shapiro (16), establishing the utility of Mosher and Hornsby's (8) 20 Questions Task as a means of differentiating families with schizophrenic patients from those of psychiatrically hospitalized but nonschizophrenic individuals. In the current study, Wild and Shapiro's original design was expanded and revised by (a) diagnosing patients using Research Diagnostic Criteria rather than hospital diagnoses and (b) including families with schizophrenic daughters and/or one-parent families, in addition to intact families with schizophrenic sons. Families were comparable on age, intelligence, and socioeconomic variables. The results failed to replicate those reported by Wild and Shapiro, and indicated that the 20 Questions Task was sensitive to differences in family constellation and offspring gender as well as offspring diagnosis. The findings suggest that forms of familial communication deviance detected with the 20 Questions Task may not be unique to families of schizophrenics, thus highlighting the need to expand research on family communication deviance in families with schizophrenic offspring to families with varied family constellations and characteristics.  相似文献   
287.
Two studies were conducted to investigate the possibility of individual differences in the ability of inpatients to process interactions in group psychotherapy. The first was a pilot study conducted on groups of major depressive patients and matched normal subjects. Subjects were asked to give process comments after viewing simulations of typical group therapy interactions. These comments were later rated on the extent to which they reflected process qualities and accuracy. These data led to a more rigorous and extensive study that included more appropriate control groups as well as measures of potential confounding factors, such as simulation realism, verbal ability, and interaction comprehension. Results indicated that major depressives suffer from deficits in the ability to process group interactions, relative to three types of control groups, including normals. These differences in processing were not significantly positively correlated with any of the potential confounding factors. The implications for understanding interactional processing and group psychotherapy are discussed.  相似文献   
288.
The cognitive effects of LOGO were examined among 11–12-year-old black and white Zimbabwean girls and boys. Fifty-two experimental group children were exposed to a BBC LOGO programme with a screen turtle. Forty-one control group children received no exposure to computers at school. Pre-tests on four WISC-R subscales were held in January, 1987 and post-tests on the same four WISC-R subscales were held in November/December, 1987. The data were analyzed with multivariate analysis of covariance, using pre-test scores as the covariate. The results suggested that children in the experimental group did better on the WISC-R Arithmetic scale and that black girls exposed to LOGO showed particular gains in spatial reasoning, as measured by the WISC-R Block Design scale. It is concluded that LOGO appears to facilitate cognitive growth. Methodological limitations of the present study are discussed and suggestions for future research are presented.  相似文献   
289.
We conducted an investigation to evaluate the effects of a training strategy for teaching autistic students generalized responses to three forms of wh— questions (what, how, and why). Students were taught, using modeling and reinforcement procedures, to answer questions with magazine pictures as the referents. Each question form was divided into two or more subcomponents reflective of common social usage and was taught within the context of a modified multiple probe design across subcomponents. Following acquisition of each subcomponent, generalization to natural context and storybook questions was assessed; additional probes were conducted to assess responding over time and whether acquisition of responses to questions promoted question-asking skills. Results showed that the picture training procedure was effective in teaching a generalized response to questions for which the relevant cue was visible, whereas specific generalization programming was required for situations in which the relevant cue was not visible. All acquired responses were durable over time.  相似文献   
290.
Family functioning of 20 alcoholic male veterans and their female partners was assessed in relation to drinking (wet) and abstinent (dry) intervals. Repeated measures analyses performed on the McMaster Family Assessment Device (FAD) indicated that on all 7 scales of the FAD, alcoholics and their mates perceived family functioning to be better during dry than wet periods. In contrast to their alcoholic mates, female partners gave healthier ratings to all FAD scales except Roles in the dry condition and Affective Involvement in the wet condition. According to published cutoff scores for healthy and unhealthy family functioning, alcoholics as a group viewed their wet and dry family functioning as unhealthy, although the female group regarded the family's dry Problem Solving and Behavioral Control as healthy. These findings suggest that the family functioning of alcohol-involved couples is biphasic, oscillating between drinking and abstinent periods.  相似文献   
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