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911.
It is important to study communication processes in families where members are undergoing testing for genetic conditions because the information received from such testing is crucial not just to the individual concerned but also to other members of the biological family. This topic has received little research attention, in part because of the complexities of methodology required. In this paper we present the development of a method specifically designed for the examination of the content and process of communication of genetic information in families. The method aims to maximize ecological validity as far as is possible. We describe how participants and other family members are recruited and how data were collected. We outline three main data analytic strategies: a graphic to show how genetic information changes as it flows from clinic and through the family, an intensive qualitative analysis of the meaning and impact of the genetic information to different family members, and an informative genogram which plots key family dynamics. This method will be illustrated in relation to a study of ten family-groups where one individual has been found to carry a genetic mutation predisposing them to hereditary breast and ovarian cancer.  相似文献   
912.
Recent theoretical and empirical developments in human category learning have differentiated an analytic, rule-based system of category learning from a nonanalytic system that integrates information across stimulus dimensions. In the present study, the researchers applied this theoretical distinction to pigeons' category learning. Pigeons learned to categorize stimuli varying in the tilt and width of their internal striping. The matched category problems had either a unidimensional (rule-based) or multidimensional (information-integration) solution. Whereas humans and nonhuman primates strongly dimensionalize these stimuli and learn rule-based tasks far more quickly than information-integration tasks, pigeons learned the two tasks equally quickly to the same accuracy level. Pigeons may represent a cognitive system in which the commitment to dimensional analysis and category rules was not strongly made. Their performance could suggest the character of the ancestral vertebrate categorization system from which that of primates emerged.  相似文献   
913.
Whether bullying in schools is increasing, as is widely believed, was investigated drawing upon empirical studies undertaken in a wide range of countries in which findings had been published describing its prevalence at different points in time between 1990 and 2009. Results do not support the view that reported bullying in general has increased during this period; in fact, a significant decrease in bullying has been reported in many countries. However, there are some indications that cyber bullying, as opposed to traditional bullying, has increased, at least during some of this period. The reported decreases in the prevalence of school bullying are consistent with reports of significant but small reductions in peer victimisation following the implementation of anti-bullying programs in schools world-wide.  相似文献   
914.
To assist road safety professionals in developing effective strategies to combat the risk associated with driving while fatigued, a survey was administered to 1000 Australian drivers. Participants reported their past behaviours in regards to driving while sleepy and their perceptions of risk associated with driving fatigued as compared to speeding and driving under the influence of alcohol. Although participants appeared to be aware of the substantial risk associated with driving while sleepy, many drivers reported that they frequently drive when sleepy. Age and gender comparisons, revealed that risk taking behaviour in regards to driving while sleepy is occurring across all age groups and in both male and female drivers. Overall young to middle age drivers and male drivers reported the highest frequency of driving while sleepy and reported the lowest perceived personal risk in regards to driving while sleepy.  相似文献   
915.
Numerous reaction time studies have suggested that age-related declines in cognitive function might be ameliorated by lifestyles involving aerobic activity or by interventionist programmes of aerobic exercise. These studies are far from conclusive, however, reflecting a failure to factor out cognitive from sensory and motor processes. Following a critical review of the literature, we report on recent developments that differentiate cognitive processes involving executive vs non-executive control, the former being associated with frontal lobe function. Three key studies suggest that aerobic exercise primarily improves executive control.  相似文献   
916.
Three experiments investigated the role of object knowledge on participants' ability to solve a spatial arrangement problem. The task was to rearrange six real-world three-dimensional objects so that their relative locations agreed with a given set of rules. The aim of the experiments was to tease out the relative extent to which object association, orientation, and object-specific functional relations affect performance on arrangement tasks. When the problem was presented vertically (objects arranged in piles), participants solved functional canonical versions of the problem significantly quicker than functional non-canonical versions both between (Experiments 1a and 2), and within subjects (Experiment 3). When the arrangement problem was presented horizontally (objects arranged flat in two rows), no significant differences in solution times were found between conditions (Experiments 1b and 2). Overall the results provide evidence for the importance of object-specific functional relations as a predictor of the solution time of spatial arrangement problems, although some differences were noted between single and multiple presentation of problems when specific rules within problems were rotated. The importance of functional information in memory as a constraint on the building of mental models and problem spaces is discussed.  相似文献   
917.
918.
Five preliminary experiments on sighted individuals revealed marked overestimation on an object size-estimation task using a bimanual response. These experiments ruled out the possibility that overestimation was due to the mode of visual presentation (whether two-dimensional or three-dimensional), the input modality (visual or kinesthetic), or the influence of other visual cues. The main experiment then investigated whether these distortions are due to visual experience by using a variant of the same task to test 24 blind and 24 sighted control participants. Remarkably, the sighted control participants overestimated object size, on average, but the blind participants did not. A follow-up experiment demonstrated that visual memory was the primary influence causing the size over-estimations. We conclude that blind individuals are more accurate than sighted individuals in representing the size of familiar objects because they rely on manual representations, which are less influenced by visual experience than are visual memory representations.  相似文献   
919.
One's expectancies for reinforcement from eating or from thinness are thought to represent summaries of one's eating-related learning history and to thus influence the development of binge-eating and purging behavior. In a 3-year longitudinal study, the authors tested this hypothesis and the hypothesis that binge eating also influences subsequent expectancy development. The authors used trajectory analysis to identify groups of middle school girls who followed different trajectories of binge eating, purging, eating expectancies, and thinness expectancies. Initial eating and thinness reinforcement expectancies identified girls whose binge eating and purging increased during middle school, and expectancies differentiated girls who began these problem behaviors from girls who did not. Initial binge-eating scores differentiated among eating expectancy developmental trajectories. The onset of most behaviors can be understood in terms of learned expectancies for reinforcement from these behaviors. The same model can be applied to the risk for eating disorders.  相似文献   
920.
We conducted an exploratory, qualitative study investigating the factors influencing the use of genetic counseling and prenatal genetic testing for two groups: pregnant women 35 years of age and over (AMA) at the time of delivery and pregnant women with an abnormal maternal serum triple screen (MSAFP3). The convenience sample consisted of 25 semistructured interviews of women/couples and 50 observations of genetic counseling sessions. Worry turned out to be the most important variable influencing decision making about prenatal genetic testing and was greater in the MSAFP3 group than in the AMA group. The women in the AMA group appeared to assign the risk of having a child with Down syndrome to their age category rather than to themselves individually, whereas, the risk perception for women with an abnormal MSAFP3 appeared to have shifted from a general population risk for pregnant women to an individual, personal risk. There was a general lack of understanding and also more misinformation about the MSAFP3 screen compared to amniocentesis. Women in both groups were torn between fear of an invasive test and worry about the health of their fetus for the rest of their pregnancy if they did not undergo amniocentesis.  相似文献   
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