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181.
Selective sex differences in declarative memory   总被引:4,自引:0,他引:4  
Sex invariance of a six-factor, higher order model of declarative memory (two second-order factors: episodic and semantic memory; and four first-order factors: recall, recognition, fluency, and knowledge) was established for 1,796 participants (35-85 years). Metric invariance of first- and second-order factor loadings across sex was demonstrated. At the second-order level, a female advantage was observed for both episodic and semantic memory. At the first-order level, sex differences in episodic memory were apparent for both recall and recognition, whereas the differences in semantic memory were driven by a female superiority in fluency. Additional tests of sex differences in three age groups (35-50, 55-65, and 70-85 years of age) indicated that the female superiority in declarative memory diminished with advancing age. The factor-specific sex differences are discussed in relation to sex differences in hippocampal function.  相似文献   
182.
Change in cognitive abilities was assessed over a 6-year period in a sample of monozygotic and same-sex dizygotic twin pairs (N = 507 individuals), aged 80 and older (mean age = 83.3 years: SD = 3.1). who remained nondemented over the course of the study. Latent growth models (LGMs) show that chronological age and time to death are consistent predictors of decline in measures of memory, reasoning, speed, and verbal abilities. Multivariate LGM analysis resulted in weak and often negative correlations among rates of change between individuals within twin pairs, indicating greater differential change within twin pairs than occurs on average across twin pairs. These findings highlight several challenges for estimating genetic sources of variance in the context of compromised health and mortality-related change.  相似文献   
183.
Three mediators of the relationship between childhood maltreatment and dating violence perpetration during midadolescence (i.e., trauma-related symptoms, attitudes justifying dating violence, and empathy and self-efficacy in dating relationships) were tested over 1 year with a sample of students from 10 high schools (N = 1,317). Trauma-related symptoms had a significant cross-time effect on predicting incidents of dating violence for both boys and girls. Attitudes and empathy and self-efficacy did not predict dating violence over time, although they were correlated with such behavior at both time points. Child maltreatment is a distal risk factor for adolescent dating violence, and trauma-related symptoms act as a significant mediator of this relationship. The importance of longitudinal methodology that separates correlates from predictors is discussed.  相似文献   
184.
This article describes cross-cultural and developmental research on folk biology: that is, the study of how people conceptualize living kinds. The combination of a conceptual module for biology and cross-cultural comparison brings a new perspective to theories of categorization and reasoning. From the standpoint of cognitive psychology, the authors find that results gathered from standard populations in industrialized societies often fail to generalize to humanity at large. For example, similarity-driven typicality and diversity effects either are not found or pattern differently when one moves beyond undergraduates. From the perspective of folk biology, standard populations may yield misleading results because they represent examples of especially impoverished experience with nature. Certain phenomena are robust across populations, consistent with notions of a core module.  相似文献   
185.
An integrated theory of the mind   总被引:23,自引:0,他引:23  
Adaptive control of thought-rational (ACT-R; J. R. Anderson & C. Lebiere, 1998) has evolved into a theory that consists of multiple modules but also explains how these modules are integrated to produce coherent cognition. The perceptual-motor modules, the goal module, and the declarative memory module are presented as examples of specialized systems in ACT-R. These modules are associated with distinct cortical regions. These modules place chunks in buffers where they can be detected by a production system that responds to patterns of information in the buffers. At any point in time, a single production rule is selected to respond to the current pattern. Subsymbolic processes serve to guide the selection of rules to fire as well as the internal operations of some modules. Much of learning involves tuning of these subsymbolic processes. A number of simple and complex empirical examples are described to illustrate how these modules function singly and in concert.  相似文献   
186.
Faculty members at Canadian business schools were surveyed regarding their ethical perceptions of behaviours related to undergraduate instruction. Fifty-five behavioural statements were listed and respondents were asked to rate the extent to which they felt each behaviour was ethical or unethical. The only item that respondents endorsed as unequivocally unethical (90% indicated it was definitely unethical) was Becoming sexually involved with an undergraduate in one of your classes. We also compared the results of our sample to those of an American sample. Overall, an interesting pattern of differences emerged between the responses obtained in Canada and the U.S. In general, the direction of the significant differences was such that Canadian professors viewed the behaviours in question as less ethical than did their American counterparts.  相似文献   
187.
Arata CM  Stafford J  Tims MS 《Adolescence》2003,38(151):567-579
The present study surveyed 930 high school students regarding self-reported alcohol use, their perceptions of parents and peers, and the negative consequences of drinking. Two-fifths of males and one-fifth of females reported frequent problem (binge) drinking. Problem drinkers reported more negative consequences associated with drinking. In addition, problem drinkers reported greater susceptibility to peer pressure, perceived their peers as drinking more, and reported less parental monitoring and more use of alcohol by parents. The results demonstrate the importance of both parent and peer variables in adolescent substance use and highlight the negative consequences of drinking reported by high school students.  相似文献   
188.
189.
This study examined the association of youth and family characteristics with therapist fidelity to an evidence-based treatment provided in real world practice settings. Participants were 233 families that reported on the 66 therapists organized into 16 teams in nine organizations providing multisystemic therapy (MST). Therapist adherence ratings were lower for youths referred for both criminal offenses and substance abuse than for youths referred either for substance abuse or status offenses, and was negatively associated with pretreatment arrests and school suspensions. Adherence ratings were positively associated with educational disadvantage and caregiver-therapist ethnic match and marginally positively associated with economic disadvantage. The findings suggest directions for future research on the implementation of evidence-based treatments in community settings.  相似文献   
190.
R. M. Baron and D. A. Kenny (1986; see record 1987-13085-001) provided clarion conceptual and methodological guidelines for testing mediational models with cross-sectional data. Graduating from cross-sectional to longitudinal designs enables researchers to make more rigorous inferences about the causal relations implied by such models. In this transition, misconceptions and erroneous assumptions are the norm. First, we describe some of the questions that arise (and misconceptions that sometimes emerge) in longitudinal tests of mediational models. We also provide a collection of tips for structural equation modeling (SEM) of mediational processes. Finally, we suggest a series of 5 steps when using SEM to test mediational processes in longitudinal designs: testing the measurement model, testing for added components, testing for omitted paths, testing the stationarity assumption, and estimating the mediational effects.  相似文献   
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