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171.
Early studies of genetic effects on brain activity have been conducted to investigate primarily either the influence of polymorphisms in dopaminergic genes, especially the catechol-O-methyltransferase (COMT) gene, on prefrontal cognitive processes such as working memory, or that of polymorphisms in the serotonin transporter gene on the amygdala response to threatening stimuli. Here, we address genetic influences on the neural systems underlying cognitive-affective interactions. Specifically, we assess the effect of the COMT val158met polymorphism on frontal regulation of attention under emotional distraction. Healthy volunteers were scanned while performing a house-matching task with affectively negative versus neutral distractors. Effects of val allele load were examined on frontal regions associated with attentional control and emotion regulation, and on parahippocampal regions associated with perception of houses. As we predicted, val load correlated positively with activity in control- and task-related regions during performance under emotional distraction. These findings provide an initial step toward identifying genetic contributions to interindividual variability in recruitment of mechanisms that regulate affective processing.  相似文献   
172.
Cognitive models of obsessive-compulsive disorder (OCD) posit that specific kinds of dysfunctional beliefs (e.g., pertaining to responsibility and the significance of intrusive thoughts) underlie the development of this disorder. The present study was designed to prospectively evaluate whether dysfunctional beliefs thought to underlie OCD act as a specific vulnerability factor in the pathogenesis of obsessive-compulsive symptomatology. Eighty-five individuals were prospectively followed over a period of time thought to be associated with an increased onset of OCD symptoms -- childbirth and the postpartum. The majority of these new mothers and fathers experienced intrusive infant-related thoughts and performed neutralizing behaviors similar to, but less severe than, those observed in OCD. Scores on a measure of dysfunctional beliefs thought to underlie OCD predicted the development of obsessive-compulsive symptoms after controlling for pre-existing OCD symptoms, anxiety, and depression. Dysfunctional beliefs also predicted the severity of checking, washing, and obsessional OCD symptom dimensions, but not neutralizing, ordering, or hoarding symptom dimensions. These data provide evidence for specific dysfunctional beliefs as risk factors in the development of some types of OCD symptoms.  相似文献   
173.
This article reports a short-term longitudinal study focusing on popularity and social acceptance as predictors of academic engagement for a sample of 342 adolescents (approximate average age of 14). These youths were followed for 4 consecutive semesters. Popularity, social acceptance, and aggression were assessed with a peer nomination inventory, and data on academic engagement were obtained from school records. For adolescents who were highly aggressive, increases in popularity were associated with increases in unexplained absences and decreases in grade point average. Conversely, changes in social acceptance were not predictive of changes in grade point average or unexplained absences. These results highlight the importance of multidimensional conceptualizations of social standing for research on school adjustment during adolescence and emphasize the potential risks associated with popularity.  相似文献   
174.
People pursue goals for a variety of reasons, including reasons that take into account close relationships (termed relationally autonomous reasons, or RARs). Two longitudinal studies examined the degree to which relational self-construal, RARs, and personally autonomous reasons (PARs) predicted goal attainment. In Study 1, 166 participants rated 7 goals on several goal outcomes at 2 sessions. Results revealed that self-construal was positively associated with RARs and that RARs predicted goal attainment, controlling for PARs. Study 2 (N = 177) added a 3rd follow-up to the Study 1 design, and results showed perceived progress toward one's goals predicted enhanced RARs but not enhanced PARs. Both studies showed that RARs are an effective motivational component in goal pursuit and attainment.  相似文献   
175.
Four experiments examined whether group formation and positive in-group regard require interaggregate comparison as the in-group-requires-an-out-group assumption of the metacontrast principle implies. The authors fostered novel social aggregates with or without a contrasting aggregate with which members could compare and varied intra-aggregate factors (interaction or interdependence). Regardless of whether interaggregate comparison was feasible, the intra-aggregate factors increased the perceived entitativity of the aggregate and positive regard toward the aggregate (i.e., social attraction and cooperation among members). Mediation analyses were consistent with the possibility that the intra-aggregate factors promoted entitativity, which in turn promoted in-group regard. These data suggest that group formation and in-group regard have intragroup origins and do not require comparison with a contrasting social aggregate.  相似文献   
176.
Individual Beck Depression Inventory (BDI) time courses of 38 clients receiving cognitive therapy (CT) and a modified form of CT were studied in order to investigate temporal changes during CT for depression. The primary aim was to determine if alternative methods of defining and computing gains occurring early in CT would alter the conclusions drawn in the current literature. Three types of gains were studied: sudden gains (previously studied sudden, substantial, and stable improvements in depression during 1 between-session interval after Session 2), first-session gains (occurring after first sessions), and pretreatment gains (occurring after pretreatment assessments). Positive outcomes were predicted by first-session gains and by sudden gains occurring in the first half of treatment, highlighting the importance of early change in CT for depression.  相似文献   
177.
The current study investigated a behavior-analytic treatment, functional analytic psychotherapy (FAP), for outpatient depression utilizing two single-subject A/A+B designs. The baseline condition was cognitive behavioral therapy. Results demonstrated treatment success in 1 client after the addition of FAP and treatment failure in the 2nd. This study highlights the challenges in measuring treatment progress and outcome idiographically in this population.  相似文献   
178.
As engineers gain experience and become experts in their domain, the structure and content of their knowledge changes. Two studies are presented that examine differences in knowledge representation among freshman and senior engineering students. The first study examines recall of mechanical devices and chunking of components, and the second examines whether seniors represent devices in a more abstract functional manner than do freshmen. The most prominent differences between these 2 groups involve their representation of the functioning of groups of electromechanical components and how these groups of components interact to produce device behavior. Seniors are better able to construct coherent representations of devices by focusing on the function of sets of components in the device. The findings from these studies highlight some ways in which the structure and content of mental representations of design knowledge differ during the early stages of expertise acquisition.  相似文献   
179.
In everyday life, the optic flow associated with the performance of complex actions, like walking through a field of obstacles and catching a ball, entails retinal flow with motion energy (first-order motion). We report the results of four complex action tasks performed in virtual environments without any retinal motion energy. Specifically, we used dynamic random-dot stereograms with single-frame lifetimes (cyclopean stimuli) such that in neither eye was there retinal motion energy or other monocular information about the actions being performed. Performance on the four tasks with the cyclopean stimuli was comparable to performance with luminance stimuli, which do provide retinal optic flow. The near equivalence of the two types of stimuli indicates that if optic flow is involved in the control of action, it is not tied to first-order retinal motion.  相似文献   
180.
Although humans typically move more slowly as they age, one exception may be the saccadic motor system. To fully determine whether the execution of saccades is affected by age, the authors examined detailed kinematics of vertical and horizontal saccades across a range of saccadic amplitudes (4 degrees, 8 degrees, and 12 degrees). Ten younger and 20 older adults participated in each experiment. Whereas in the 1st experiment, the authors assessed volitionally generated saccades, in the 2nd experiment, they evaluated reflexively generated saccades. The results of those experiments showed that the saccadic motor system is relatively impervious to the effects of aging; in fact, the differences between vertical and horizontal saccades were more evident than were differences between saccades produced by younger and older adults. The authors discuss possible reasons for that relative resistance to aging.  相似文献   
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