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861.
Perception by adults is a constant interaction between the top-down effects of prior knowledge and the effects of bottom-up perceptual information. One obvious example of this interaction is the perceptual restoration effect, in which adult listeners have the illusion that a word is complete when a portion of it has been replaced by a masking noise. In four experiments, we demonstrate that toddlers fail to show the illusion of perceptual restoration, even in constrained situations with words they know quite well. Not only do toddlers have less prior knowledge than do adults, but they also appear to place less reliance on the knowledge that they do have, at least in the paradigm tested here. Instead, toddlers appear to be more tied to the perceptual information they receive than are adults.  相似文献   
862.
Insight occurs when problem solutions arise suddenly and seem obviously correct, and is associated with an "Aha!" experience. Prior theorizing concerning preparation that facilitates insight focused on solvers' problem-specific knowledge. We hypothesized that a distinct type of mental preparation, manifested in a distinct brain state, would facilitate insight problem solving independently of problem-specific knowledge. Consistent with this hypothesis, neural activity during a preparatory interval before subjects saw verbal problems predicted which problems they would subsequently solve with, versus without, self-reported insight. Specifically, electroencephalographic topography and frequency (Experiment 1) and functional magnetic resonance imaging signal (Experiment 2) both suggest that mental preparation leading to insight involves heightened activity in medial frontal areas associated with cognitive control and in temporal areas associated with semantic processing. The results for electroencephalographic topography suggest that noninsight preparation, in contrast, involves increased occipital activity consistent with an increase in externally directed visual attention. Thus, general preparatory mechanisms modulate problem-solving strategy.  相似文献   
863.
Antisocial personality disorder (ASPD) and psychopathy are two syndromes with substantial construct validity. To clarify relations between these syndromes, the authors evaluated 3 possibilities: (a) that ASPD with psychopathy and ASPD without psychopathy reflect a common underlying pathophysiology; (b) that ASPD with psychopathy and ASPD without psychopathy identify 2 distinct syndromes, similar in some respects; and (c) that most correlates of ASPD reflect its comorbidity with psychopathy. Participants were 472 incarcerated European American men who met Diagnostic and Statistical Manual (4th ed., American Psychiatric Association, 1994) criteria for ASPD and Psychopathy Checklist criteria for psychopathy, who met the criteria for ASPD but not for psychopathy, or who did not meet diagnostic criteria for either ASPD or psychopathy (controls). Both individuals with ASPD only and those with ASPD and psychopathy were characterized by more criminal activity than were controls. In addition, ASPD with psychopathy was associated with more severe criminal behavior and weaker emotion facilitation than ASPD alone. Group differences in the association between emotion dysfunction and criminal behavior suggest tentatively that ASPD with and ASPD without prominent psychopathic features may be distinct syndromes.  相似文献   
864.
The major aim of this study was to examine the longitudinal association between adolescent smoking involvement and self-reported psychological and physical outcomes in young adulthood. Participants included 333 African Americans and 329 Puerto Ricans who were surveyed in 1990 in their New York City schools and interviewed in 1995 and 2000-2001, primarily in their homes. The psychological outcomes included ego integration, symptoms of depression, anxiety, and interpersonal difficulty. The physical health measures included a general health rating, number of illnesses, and symptoms of ill health. Also, three scales measured problems due to alcohol, marijuana, and other illicit drug use. Smoking involvement varied by age, sex, and ethnicity but not by socioeconomic status nor by late adolescent parental status. Analysis showed that the relationships between adolescent smoking involvement and psychological and physical health problems in young adulthood remained significant even with control on demographic factors, earlier levels of the outcome variables, and marijuana use. The relationships between smoking behavior and problems with alcohol, marijuana and other illicit drug use were particularly strong. Thus, adolescent smoking seems to have a wide range of clinical implications for young adulthood.  相似文献   
865.
The current study examined the behaviors related to academic engagement exhibited by students with ADHD during instruction in math and reading. A total of 155 students (92 ADHD, 63 recruited controls) in grades 1 through 4 participated in the study. Results revealed that students with ADHD exhibited statistically significant lower rates of academic engagement and higher rates of off-task behaviors than recruited controls and randomly selected peer comparisons. Specifically, students with ADHD exhibited statistically significant lower rates of passive academic engagement (PET) than recruited controls and peer comparisons; however no group differences were found with regard to active engaged time (AET). In addition, students with ADHD exhibited lower rates of AET than PET, a finding observed among both recruited controls and randomly selected peer comparisons. Implications for research and practice are discussed.  相似文献   
866.
The term "pilot study" has been used over the years to describe the evaluation of the many elements involved in deciding whether a proposed condition should be added to a newborn screening (NBS) panel, and until recently, was unilaterally used to describe the evaluation of the assay to be used before the condition was officially adopted by a state for its newborn screening panel. Since Guthrie's introduction of screening for PKU, each time a new condition was added to the panel, the screening assay itself was validated through a population-based trial, in which the test was performed with de-identified samples to avoid association between the test result and the infant. This is considered by the laboratory as the "pilot phase" of adding a new condition. To advance the science of NBS, especially to accommodate new technologies that may provide new types of information (genetic versus physiological) for each new condition, pilot programs are essential. Involvement of the clinical community serves to improve these evaluations and provides the needed clinical validation of decisions made as a result of it. This paper describes the historical context of pilot programs in population-based NBS that utilize laboratory-based markers as indicators of concern; specifically, three applications that demonstrate different approaches to the use of pilots in adding conditions to a NBS panel are described.  相似文献   
867.
868.
The Implicit Association Test (IAT) was used to investigate automatic fear associations in fear of spiders. Fear associations toward spiders were measured among spider fearful and nonfearful participants (Experiment 1) as well as among nonfearfuls and spider enthusiasts (Experiment 2). It was shown that the IAT is sensitive to personal automatic fear associations and therefore distinguishes between high-fearful, nonfearful, and enthusiastic participants. Moreover, implicit spider associations measured by the IAT predicted avoidance behavior beyond self-reports. The results of Experiment 2 provide additional support for the argument that implicit spider associations are different from general stereotypes or knowledge about spiders.  相似文献   
869.
We explored college students' discrimination of complex visual stimuli that involvedmultiple-item displays. The items in each of the displays could be all the same, all different, or diverse mixtures of some same and some different items. The participants had to learn which of two arbitrary responses was correct for each of the displays without being told about the sameness or differentness of the stimuli. We observed a general improvement in discrimination performance--a rise in choice accuracy and a fall in reaction time-as the number of icons in the display was increased, even when the participants had been trained from the outset with displays containing different numbers of items and when smaller numbers of items were not randomly distributed but grouped in the center of the display. The participants' discrimination behavior also depended on the mixture of same and different items in the displays. Striking individual differences in the participants' discrimination behavior disclosed that people sometimes respond as do pigeons and baboons trained with a similar task. This and previous related research suggest that variability discrimination may lie at the root of same-different categorization behavior.  相似文献   
870.
In order to estimate the effects of affluence on political attitudes, we conducted interviews with 342 people who had won the lottery between 1983 and 2000 in an Eastern state. A parallel survey of the general public was also conducted. Comparing winners of varying amounts, we find that lottery-induced affluence increases hostility toward estate taxes, marginally increases hostility towards government redistribution, but has little effect on broader attitudes concerning economic stratification or the role of government as a provider of social insurance. These results bolster previous findings suggesting that economic self-interest influences policy preferences when policy consequences are perceived as salient. At the same time, the findings suggest the limited influence that material concerns have on one's broad political outlook.  相似文献   
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