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211.
Few cross-national reports have examined suicide rates among adolescents and young adults. A survey of suicides among 15-24-year-olds in 34 of the wealthiest nations demonstrated that 15,555 youths killed themselves in a 1-year study period. Thirty-four percent of these suicides were firearm-related. Finland led the participating nations in total and firearm-related suicide rates. An association was found between divorce rates and youth suicide rates, firearm-related suicide among youths, and suicide rates among young males. For a smaller sample of countries, an association was found between firearm availability and firearm-related suicide rates among youths and suicide rates among young males.  相似文献   
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A common way of studying developmental disorders is to adopt a static neuropsychological deficit approach, in which the brain is characterized in terms of a normal brain with some parts or ‘modules’ impaired. In this paper we outline a neuroconstructivist approach in which developmental disorders are viewed as alternative developmental trajectories in the emergence of representations within neural networks. As a concrete instantiation of the assumptions underlying this general approach, we present a number of simulations in an artificial neural network model. The representations that emerge under different architectural, input and developmental timing conditions are then analysed within a multi‐dimensional state space. We explore alternative developmental trajectories in these simulations, demonstrating how initial differences in the same parameter can lead to very different outcomes, and conversely how different starting states can sometimes result in similar end states (phenotypes). We conclude that the assumptions of the neuroconstructivist approach are likely to be more appropriate for analysing developmental deviations in complex dynamic neural networks, such as the human brain.  相似文献   
215.
Attitudes toward older and younger adults: a meta-analysis   总被引:3,自引:0,他引:3  
Attitudes toward the elderly have been examined in a number of empirical studies, yet the question of whether the elderly are viewed more negatively than younger persons has not been resolved. A meta-analysis of the literature was conducted to examine this question; results demonstrated that attitudes toward the elderly are more negative than attitudes toward younger people. However, smaller differences between the evaluations of elderly and younger targets were found when (a) the study used measures of personality traits (compared with measures of competence), (b) there were a larger number of dependent measures included in the effect size, (c) specific information was provided about the target person (compared with when a general target such as old person was used), and (d) a between-subjects design (compared with a within-subjects design) was used. These results support Lutsky's (1981) conclusion that age, in and of itself, seems to be less important in determining attitudes toward the elderly than other types of information. The methodological limitations within the literature and a need to consider multiple components of attitudes toward older individuals are discussed.  相似文献   
216.
Twenty-six suicide attempters, 9 to 18 years of age, were compared with 725 nonattempters on measures of school achievement, educational goals, socioeconomic status, and depression. As has been found in studies using clinical samples, suicide attempters in our communitybased sample had significantly lower school achievement than nonattempters. The relationship between attempted suicide and low school achievement seemed to be explained by the effects of depression. Lower-SES youth tended to be more likely to attempt suicide than higher-SES youths. However, SES appeared to have little effect on the relationship between attempted suicide and school achievement. Results also suggest that children of mothers with low educational goals for them may be more at risk for attempted suicide than youths whose mothers have higher educational goals for their children.This research was supported by the National Institute of Mental Health, Grant No. MH36971.  相似文献   
217.
Durkheim divided suicide into four social types; egoistic, anomic, fatalistic, and altruistic assigning the first two to modern, western society while relegating the last two to pre-industrial social orders. However, contemporary studies of female suicidal behavior and depression show that such women exhibit personality characteristics of low self-esteem, passivity, dependence and living vicariously for others which correspond to the behavioral indices of impersonalism, submissiveness, passivity, and obedience that produce the lack of individuation characteristic of Durkheim's altruistic/fatalistic suicide categories. On this basis, the author suggests that altruistic/fatalistic suicide may even in the modern world be relevant to the explanation of female suicidal behavior, a hypothesis which, if true, would support the contention that "men and women inhibit different social worlds."  相似文献   
218.
Selectively reviewing some items from a larger set of previously learned items increases memory for the items that are reviewed but may also be accompanied by a cost: Memory for the nonreviewed items may be impaired relative to cases where no review occurs at all. This cost to nonreviewed items has primarily been shown in contexts of verbal list learning and in situations where the reviewed and nonreviewed items are categorically or semantically related. Using a more naturalistic impetus to selective review--photographs relating to previously experienced events--we assessed whether the memory of older and younger adults for unrelated complex activities that they themselves had performed was also impaired due to nonreview. Both younger and older adults showed impaired memory for nonreviewed activities when tested with free recall (Experiment 1), but not when tested with recognition or cued recall (Experiment 2). If mitigating retrieval cues are unavailable, selective review may impair memory for nonreviewed everyday events.  相似文献   
219.
Three perspectives on addiction promulgated during the 1990s are reviewed, along with many earlier contributions to the understanding of addictive illness. It is suggested that these distinct yet overlapping formulations of the dynamics of addiction form a hierarchy for each patient suffering from an addiction. Assessment of a patient's ego strength, and of the relative importance of addictive behaviors in overall character structure, allows referral to various types of treatment, including psychoanalytic therapy. Case examples are presented, including material from the psychoanalysis of a woman addicted to heroin, methadone, cocaine, amphetamines, nicotine, alcohol, and shopping.  相似文献   
220.
Ratings of familiarity and pronounceability were obtained from a random sample of 199 surnames (selected from over 80,000 entries in the Purdue University phone book) and 199 nouns (from the Ku?era-Francis, 1967, word database). The distributions of ratings for nouns versus names are substantially different: Nouns were rated as more familiar and easier to pronounce than surnames. Frequency and familiarity were more closely related in the proper name pool than the word pool, although both correlations were modest. Ratings of familiarity and pronounceability were highly related for both groups. A production experiment showed that rated pronounceability was highly related to the time taken to produce a name. These data confirm the common belief that there are differences in the statistical and distributional properties of words as compared to proper names. The value of using frequency and the ratings of familiarity and pronounceability for predicting variations in actual pronunciations of words and names are discussed.  相似文献   
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