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851.
    
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852.
In Drosophila, calcium/calmodulin-dependent protein kinase II (CaMKII) activity is crucial in associative courtship conditioning for both memory formation and suppression of courtship during training with a mated female. We have previously shown that increasing levels of constitutively active CaMKII, but not calcium-dependent CaMKII, in a subset of neurons can decrease the initial level of courtship and enhance the rate of suppression of courtship in response to a mated female. In this study, we demonstrate that a subpopulation of noncholinergic, nondopaminergic, non-GABAergic neurons can cause CaMKII-dependent reductions in initial courtship, but only cholinergic neurons enhance training-dependent suppression. These data suggest that processing of pheromonal signals in two subpopulations of neurons, likely antennal lobe projection neurons, is critical for behavioral plasticity.  相似文献   
853.
An extensive body of research documents the high prevalence of comorbidity among child and adolescent disorders in general and between conduct problems and depression in particular. These problems co-occur at significantly higher rates than would be expected by chance and their comorbidity may have significant implications for nosology, treatment, and prognosis. Four main hypotheses have been put forth to account for these high rates of comorbidity. First, comorbidity may be a result of shortcomings associated with referral or informant biases. Second, comorbidity may be an artifact of overlapping definitional criteria. Third, one disorder may cause the other disorder by influencing the developmental trajectory and placing an individual at increased risk for further difficulties. Finally, comorbidity between two disorders may be explained by shared underlying causal or risk factors. The purpose of this review is to explore these possibilities, concentrating primarily on the common risk factors of parent psychopathology, emotion regulation, and cognitive biases that may underlie the co-occurrence of these two disorders. Based on our review, we propose a model for the development of comorbidity between these two disorders.  相似文献   
854.
Research in older Caucasians has demonstrated that cognitive activity is related to cognitive function in late adulthood. Knowledge of this association is limited in older minority populations. We examined the relation of cognitive activity and access to cognitive resources, with cognitive function in a group of 108 older African Americans. We constructed two scales to measure the frequency of cognitive activity and the presence of resources that promote cognitive activity during early and late life. Both measures had high internal consistency and the cognitive activity scale had adequate temporal stability over a 4-week interval. In analyses that controlled for age and education, more frequent lifetime cognitive activity was related to current cognitive function, but lifetime cognitive resources only approached significance. The results suggest that both measures are psychometrically sound in a minority population and that lifetime cognitive activity may contribute to current cognitive function in African Americans.  相似文献   
855.
This exploratory study examined religious identity among Christian Korean-American adolescents. Marcia's 1966 model of identity formation, which conceptualizes identity along dimensions of exploration and commitment, provided the framework for the current study. 49 participants, between the ages of 14 and 19 years, completed the Duke Religion Index, the religion items from the Extended Objective Measure of Ego Identity Status, the Pan-denominational Measure of Personal Devotion and Personal Conservatism, and six questions assessing perceived parental involvement. Analysis indicated that high scores on Organizational and Intrinsic Religiosity were positively correlated with the commitment statuses of Achievement and Foreclosure and negatively correlated with the noncommitment statuses of Moratorium and Diffusion. Also high scores on perceived parental involvement were positively correlated with the nonexploration status of Foreclosure and negatively correlated with the exploration status of Moratorium. Overall, the study provided a general portrait and initial examination of the formation of religious identity in a sample of Christian Korean-American adolescents.  相似文献   
856.
This study examined whether certain personality characteristics are associated with susceptibility to false memories. Participants first answered questions from the Myers-Briggs Type Indicator in order to measure various personality characteristics. They then watched a video excerpt, the simulated eyewitness event. They were next encouraged to lie about the videotaped event during an interview. A week later, some participants recognized confabulated events as being from the video. Two personality characteristics in particular--the introversion-extroversion and thinking-feeling dimensions--were associated with susceptibility to false memories.  相似文献   
857.
Studying play behavior in octopuses is an important step toward understanding the phylogenetic origins and function of play as well as the cognitive abilities of invertebrates. Fourteen Octopus vulgaris (7 subadults and 7 adults) were presented 2 Lego objects and 2 different food items on 7 consecutive days under 2 different levels of food deprivation. Nine subjects showed play-like behavior with the Lego objects. There was no significant difference in play-like behavior corresponding to food deprivation, age, and sex of the octopuses. The sequence of behaviors, from exploration to play-like behavior, had a significant influence on the establishment of play-like behavior, as it occurred mostly on Days 3-6 of the 7-day experiment. The pattern of development of play-like activities after a period of exploration and habituation in this study agrees with the hypothesis that object play follows object exploration. A homologous origin of this behavioral trait in vertebrates and invertebrates is highly unlikely, as the last common ancestor might not have had the cognitive capacity to possess this trait.  相似文献   
858.
Loss aversion occurs because people expect losses to have greater hedonic impact than gains of equal magnitude. In two studies, people predicted that losses in a gambling task would have greater hedonic impact than would gains of equal magnitude, but when people actually gambled, losses did not have as much of an emotional impact as they predicted. People overestimated the hedonic impact of losses because they underestimated their tendency to rationalize losses and overestimated their tendency to dwell on losses. The asymmetrical impact of losses and gains was thus more a property of affective forecasts than a property of affective experience.  相似文献   
859.
Researchers previously have investigated the role of race in capital sentencing, and in particular, whether the race of the defendant or victim influences the likelihood of a death sentence. In the present study, we examined whether the likelihood of being sentenced to death is influenced by the degree to which a Black defendant is perceived to have a stereotypically Black appearance. Controlling for a wide array of factors, we found that in cases involving a White victim, the more stereotypically Black a defendant is perceived to be, the more likely that person is to be sentenced to death.  相似文献   
860.
Repeated administration of cognitive tests improves test performance, making it difficult for researchers to gauge the true extent of age-related cognitive decline. The authors examined this issue using data from the Rush Religious Orders Study and linear mixed-effects models. At annual intervals for up to 8 years, more than 800 older Catholic clergy members completed the same set of 19 cognitive tests from which previously established composite measures of cognitive domains were derived. Retest effects on some measures were substantial and continued to accumulate even after 8 annual test readministrations, but effects on other measures were minimal. Across cognitive measures, retest effects were not related to age, sex, or education. Individual differences in retest effects were substantial but not consistent across cognitive measures. The results suggest that retest-based improvement in cognitive test performance can be substantial and persistent.  相似文献   
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