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181.
Aggressivity, inattention, hyperactivity, and impulsivity are cardinal dimensions of externalizing behavior problems of childhood. They are diagnostic and clinical features of childhood disorders, and are thought to be linked to the subsequent development of adult disorders such as substance abuse (SA). Little is known, however, about the convergent and discriminant validity of these four constructs. We used multiple measures to develop indices of aggressivity, inattention, hyperactivity, and impulsivity in a sample of 10- to 12-year-old boys (N=183) with and without a family history of SA. Data were taken from mother reports, child reports, teacher reports, and laboratory tasks. The study aims were (1) to test the convergent and discriminant validity of aggressivity, inattention, hyperactivity, and impulsivity; (2) to examine whether the data were consistent with a model specifying the four constructs as indicators of one superordinate factor; and (3) to differentiate boys with and without a family history of SA in construct scores. The results supported the convergent and discriminant validity of the four constructs. Although discriminable, the constructs covaried strongly and were consistent with a model specifying them as indicators of a single superordinate factor. Boys with a family history of substance abuse scored higher than control boys on aggressivity, inattention, and impulsivity scores, but the groups did not differ on hyperactivity scores. The results are discussed in terms of the role of childhood behavior problems in vulnerability to SA.This work was supported by the National Institute on Drug Abuse grant No. DA 05605.  相似文献   
182.
Five parents of nonverbal children were trained in two home settings to modify antecedents and consequences to their children's vocalizations. Generalization effects of the parent training on both the parent's and children's behaviors under different stimulus conditions were investigated using multiple-baseline designs. Increases in parent prompting and reinforcing their children's vocalizations generalized only minimally to a new setting in the home where parent training had not occurred. Child increases in vocalizations produced by the parents in the training settings did generalize to this new setting in the home. There was minimal generalization of child vocalizations to a free-play setting at school. In a formal speech session conducted by a behavior specialist at school, only one child showed definite increases in acquisition rate as a function of the parents starting to train the sound at home.  相似文献   
183.
In an effort to examine whether normal blood gas tensions were essential for conditioning, paralyzed rats received a classical aversive heart rate (HR) conditioning session while respirated at different peak expired CO3 values. After the session, arterial blood was drawn for analysis. That peak expired CO2 was effective in manipulating Pco2 was indicated by a significant correlation (r = 0.594, df = 17, P < 0.05). In addition, only rats with blood gas values similar to those of anesthetized controls displayed a discriminated HR CR. These animals also had lower baseline HRs and greater HR variability. Further, 7 of the 9 rats with normal blood gas values were respirated at peak expired CO2 values from 5.0–5.1 per cent, and no animal ventilated within this range displayed abnormal values. These findings suggest that previous difficulties in obtaining classical and operant conditioning in paralyzed animals may, in part, be attributable to inadequate ventilation.  相似文献   
184.
185.
It is well-known that word frequency and predictability affect processing time. These effects change magnitude across tasks, but studies testing this use tasks with different response types (e.g., lexical decision, naming, and fixation time during reading; Schilling, Rayner, & Chumbley, 1998), preventing direct comparison. Recently, Kaakinen and Hyönä (2010) overcame this problem, comparing fixation times in reading for comprehension and proofreading, showing that the frequency effect was larger in proofreading than in reading. This result could be explained by readers exhibiting substantial cognitive flexibility, and qualitatively changing how they process words in the proofreading task in a way that magnifies effects of word frequency. Alternatively, readers may not change word processing so dramatically, and instead may perform more careful identification generally, increasing the magnitude of many word processing effects (e.g., both frequency and predictability). We tested these possibilities with two experiments: subjects read for comprehension and then proofread for spelling errors (letter transpositions) that produce nonwords (e.g., trcak for track as in Kaakinen & Hyönä) or that produce real but unintended words (e.g., trial for trail) to compare how the task changes these effects. Replicating Kaakinen and Hyönä, frequency effects increased during proofreading. However, predictability effects only increased when integration with the sentence context was necessary to detect errors (i.e., when spelling errors produced words that were inappropriate in the sentence; trial for trail). The results suggest that readers adopt sophisticated word processing strategies to accommodate task demands.  相似文献   
186.
Two studies examined how individuals' perceptions of self and others are associated with different emotional traits. Study 1 (N = 386) used structural equation modeling of questionnaire data to examine the relations between emotional traits (i.e., affect intensity, affect variability, and trait pleasant and unpleasant affect) and self- and other-perceptions (i.e., self-instability, self-esteem, other-instability, and perceived treatment by others). Study 2 (N = 99) used path analyses of data collected using an event sampling method in which online measures of emotional experiences (i.e., intensity, frequency, and variability of pleasant and unpleasant affect) as well as perceptions of self and others (i.e., self-instability, self-esteem, other-instability, perceived treatment by others) were collected. The strongest and most consistent finding was that affect variability was associated with both self- and other-instability. The results linking affect intensity with self- and other-instability were limited to negative intensity. There was also evidence of pleasant affect being associated with both self-esteem and perceived treatment by others, and unpleasant affect being associated with self-esteem and other-instability.  相似文献   
187.
The association of specific events with the context in which they occur is a fundamental feature of episodic memory. However, the underlying network mechanisms generating what-where associations are poorly understood. Recently we reported that some hippocampal principal neurons develop representations of specific events occurring in particular locations (item-position cells). Here, we investigate the emergence of item-position selectivity as rats learn new associations for reward and find that before the animal's performance rises above chance in the task, neurons that will later become item-position cells have a strong selective bias toward one of two behavioral responses, which the animal will subsequently make to that stimulus. This response bias results in an asymmetry of neural activity on correct and error trials that could drive the emergence of particular item specificities based on a simple reward-driven synaptic plasticity mechanism.  相似文献   
188.
Four experiments explored the hypothesis that temporal processes may be represented and controlled explicitly or implicitly. Tasks hypothesized to require explicit timing were duration discrimination, tapping, and intermittent circle drawing. In contrast, it was hypothesized that timing control during continuous circle drawing does not rely on an explicit temporal representation; rather, temporal control is an emergent property of other control processes (i.e., timing is controlled implicitly). Temporal consistency on the tapping and intermittent drawing tasks was related, and performance on both of these tasks was correlated with temporal acuity on an auditory duration discrimination task. However, timing variability of these 3 tasks was not correlated with timing variability of continuous circle drawing. These results support the hypothesized distinction between explicit and implicit temporal representations.  相似文献   
189.
From an eligible population of 9,943 casino employees, 6,067 volunteered to participate in this study. Of this sample, 1,176 provided data at 3 observation points approximately 12 months apart. Using the South Oaks Gambling Screen (SOGS; H. R. Lesieur & S. B. Blume, 1987) and the CAGE (J. A. Ewing, 1984) questionnaire, the authors prospectively examined the prevalence and patterns of alcohol and gambling problems among those employees. Among the casino employees with gambling and drinking problems, a segment displayed the capacity to diminish those problems even when the difficulties had reached disordered levels. The authors also examined the comorbidity of gambling and drinking as well as the relationships among changes in SOGS scores and CAGE scores and changes in demographic and biological variables. The women were more likely to decrease their problem-drinking scores, but not their gambling scores, when compared with the men. In addition, 2 key variables (i.e., disabling depression and dissatisfaction with one's personal life) emerged as predictors of transitions to healthier levels of disordered gambling. The authors cautiously suggest, in light of the results taken together, that more fluctuation is associated with gambling and drinking problems than previously thought and that the conventional wisdom about disordered gambling as "always progressive" needs reconsideration.  相似文献   
190.
Social support is protective against the negative effects of trauma, yet how these effects vary across sources of support and patterns of trauma exposure has not been examined. High co-occurrence exists among different types of trauma across domains and ages, yielding patterns of trauma exposure that may affect social support. This study identified profiles of potentially traumatic events (PTEs) experienced by 252 college students and examined the relationships between social support and mental health across these profiles. Five profiles emerged: “Non-Interpersonal Trauma Exposure,” “Adult Intimate Partner Violence,” “Poly-trauma Exposure,” “Low Trauma Exposure,” and “Childhood Family Violence.” The link between social support and adjustment differed across profiles. Family support was valuable for promoting resilience across patterns of PTEs. Friend and romantic partner support were related to lower mental health problems. Support from family and friends is particularly valuable in the context of adult intimate partner violence and childhood family violence.  相似文献   
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