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861.
Intelligence is an important indicator of physical, mental and social well-being. In old age, intelligence is also associated with a higher quality of life and better health. Heritability studies have shown that there are strong genetic influences, yet unknown, on intelligence, including in old age. Other approaches may be useful to investigate the biological foundations of intelligence differences. Proteomics is a proven technique in revealing biomarkers for certain illnesses. In this pilot study, forty individuals were selected as the cognitive extremes from over 750 people in the Lothian Birth Cohort 1936 (age ~ 72 years) based on their high and low intelligence scores, as measured by a general cognitive ability factor. Urine samples were used as a stable, reliable and abundant source of proteins. Using capillary electrophoresis coupled to mass spectrometry (CE-MS) technology, the proteome of the high and low intelligence groups was determined. Data were calibrated and matched against the human urinary database, to enable comparative assessment. At a nominal significance level (P < 0.05), there were several candidate proteins for association with intelligence, including a zinc finger protein (ZNF653) that has been associated with cognitive deficits, and complement C3 and collagen fragments that have been associated with Alzheimer's disease. Results are preliminary, do not survive multiple testing correction, and require validation. This pilot study shows the potential of this novel proteomics approach, and its applicability to understanding the biological foundations of intelligence differences.  相似文献   
862.
In the course of all motor behavior, the brain is limited in how much information it can process and act upon at a time. Performers must constantly decide where to look, what to attend to, and how to time fixated information with precisely controlled actions. The gaze can be directed to only one location at a time and information central to success must be selected from spatially complex environments, most often under severe time constraints. The coordination of these processes is explored in this Special issue in a number of motor tasks, including golf, soccer, law enforcement, and ballet. The papers describe the visual information and quiet eye characteristics that underlie the ability to make decisions under complex task conditions and the relationship between control of the gaze and task outcomes. With the attainment of motor expertise, measureable changes occur within the gaze, cognitive, and neural systems that are useful in training, rehabilitation, and the treatment of motor deficits.  相似文献   
863.
In the research area, the criterion to test a hypothesis is frequently the distance of each subject from the mean of the distribution. This concept of distance is constantly used and re-used as a source of evidence in the search for significant contrasts with respect to models of theoretical probability. This paper proposes a number of ideas regarding the use of new distance indicators related to statistics that rely less heavily on parametric assumptions, in particular, the use of median confidence intervals. We have simulated via EXCEL different data samples for a design of two independent groups under 15 different conditions in two different situations: mean equality and mean differences. The results showed the high sensitivity of the comparison of the confidence intervals, especially if a strict decision criterion is used. However, we did not obtain good results for sensitivity. In fact, in some cases, the comparison of the confidence intervals of the mean worked better than those of median.  相似文献   
864.
The aim of this paper is to present a mathematical dynamic modelling of the effect a stimulant drug has on different people which, at the same time, can be a useful tool for future brain studies. To this end, a dynamic model of the evolution of extraversion (considering its tonic and phasic aspects) has been constructed taking into account the unique personality trait theory and the general modelling methodology. This model consists of a delayed differential equation which, on one hand, considers that the active stimulus, a consequence of a single intake, is not constant; on the other hand, it contemplates that the state variable representing the phasic extraversion also represents the brain activation. The derivative of this state variable is calculated as the sum of the homeostatic control flow, the excitatory effect flow and the inhibitor effect flow. The solutions of this equation relate the tonic activation of an individual (that characterizes his or her personality) with his or her phasic activation level, whose evolution over time describes the organism's response to a single drug intake. These solutions quantitatively reproduce the predictions of current personality theories and anticipate vulnerability to drug misuse and addiction development.  相似文献   
865.
Social competence, peer status, and clinical symptomatology were evaluated in 54 child psychiatric inpatients. Aims were (a) to evaluate whether social competence deficits and peer rejection within an inpatient setting were associated with particular childhood disorders, and (b) to identify predictors of peer status in emerging groups of child inpatients. Results indicated that children with externalizing disorders (conduct or attention deficit disorders) and children with concurrent depressive and externalizing disorders were the most rejected, least liked, and least socially competent children. Depressed children without externalizing disorders had the highest scores on the social status and competence measures. Predictors of peer rejection and acceptance in the hospital differed, with measures of symptomatology predicting peer rejection, and measures of social and intellectual competence predicting peer acceptance. Implications of the results for understanding the role of peer adjustment and social competence in developmental psychopathology were discussed.This research was supported in part by Biomedical Research Support Grant RR756 awarded to the author. The author wishes to thank Donald Guthrie and Sondra Purdue for their statistical consultation, Gwen Gordon for her computer assistance, and Joan Trumbull for her assistance with data collection.  相似文献   
866.
In three experiments rats were given short or long preexposure (4 or 10 sessions) to two compound flavours, AX and BX, according to an intermixed or a blocked schedule. Following preexposure, aversion conditioning trials were given with AX as the conditioned stimulus (CS). In Experiments 1 and 2, retardation and summation tests were then carried out to assess the inhibitory properties of B (an Espinet procedure). In Experiment 3, test trials evaluated generalization from AX to BX (the standard perceptual learning procedure). The results showed that B performed as an inhibitor of the unconditioned stimulus (US; an Espinet effect) only after long intermixed preexposure, whereas a reliable perceptual learning effect was observed both after short and after long preeexposure. The observation that B had no detectable inhibitory properties after short preexposure casts doubt on the suggestion that inhibitory learning is responsible for perceptual learning after brief exposure to AX and BX.  相似文献   
867.
The origins and functions of feeling economically dependent on one's job were examined among a sample of 168 hospital workers. As predicted, economic dependency was found to be greater the more dependents workers have, the less money they earn from their jobs, the less other income they have in their family units, the more they adhere to an instrumental work orientation, and the less mobile they perceive themselves to be. Also as predicted, it was found that economic dependency fully mediated the relationship between 4 of the 5 antecedents (number of dependents, other income, instrumental values, and perceived mobility) and the subjective well-being of workers. Job-related income was observed to have both direct and indirect effects. Further, the relationship between economic dependency and subjective well-being was negative. These latter findings are discussed and implications drawn for the future use of the economic dependency construct.  相似文献   
868.
Lopez MN  Lazar MD  Oh S 《Assessment》2003,10(1):66-70
The psychometric properties of the Hooper Vsual Organization Test (VOT) have not been well investigated Here the authors present internal consistency and interrater reliability coefficients, and an item analysis, using data from a sample (N = 281) of "cognitively impaired" and "cognitively intact" patients, and patients with undetermined cognitive status. Coefficient alpha for the VOT total sample was .882. An item analysis found that 26 of the 30 items were good at discriminating among patients. Also, the interrater reliabilities for three raters (.992), two raters (.988), and one rater (.977) were excellent. Therefore, the judgmental scoring of the VOT does not interfere significantly with its clinical utility. The authors conclude that the VOT is a psychometrically sound test.  相似文献   
869.
In a concurrent validity study, a comprehensive job analysis of a mid-level secretarial position resulted in the development of highly valid employment selection instruments. Six hundred fifty-nine supervisors and 883 incumbents in 20 locations participated in the job analysis. Scores from the selection test correlated with composite ratings from a research performance appraisal (RPA) .41 (p<.001). Two forms of the test (A and B) were developed. Form A and Form B test scores and RPA composite ratings correlated .55 and .48 (p<.001) respectively. The unbiased estimate of equivalence reliability of Form A and Form B was .94. The two tests correlated .89 (p<.001).  相似文献   
870.
Operant and cognitive-behavioral models of chronic pain have called attention to the importance of examining the marital and family environments of chronic pain patients. In this study, 50 chronic pain patients and their spouses and 33 control participants and their spouses completed measures of the family environment, marital satisfaction, and patient physical and psychological functioning. Patients' overt pain behaviors were coded from videotapes of patient–spouse interactions. Compared to controls, pain patients and their spouses rated their family environments as lower in cohesion and higher in control, and there was a trend for spouses to report more marital dissatisfaction. Chronic pain patient depression was associated negatively with patient-rated family cohesion and expressiveness and spouse-rated family organization and positively with patient-rated family conflict. Overt patient pain behaviors and spouse-rated patient disability were related negatively to spouse-rated family cohesion. Spouse marital satisfaction was associated negatively with patient depression and with spouse ratings of patient disability and pain behaviors.  相似文献   
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