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121.
Research on feigned mental disorders indicates that severe psychopathology coupled with significant trauma histories often complicate feigning determinations, resulting in inaccuracies on otherwise effective measures. As part of malingering assessments, the Personality Assessment Inventory (PAI) is often used because of its excellent validation and the availability of three feigning indicators (Negative Impression, Malingering Index, and Rogers Discriminant Function), which have evidenced large effect sizes and clinically useful cut scores. The current study examined the effectiveness of the PAI in a traumatized inpatient sample using a between-subjects simulation design. Although Negative Impression appeared affected by trauma--especially in conjunction with dissociative symptoms--very positive results were found for Malingering Index and Rogers Discriminant Function. They remained relatively unelevated under honest conditions, despite posttraumatic stress disorder and extensive comorbidity. Using single-point cut scores provided moderately good classification of feigned and genuine PAI profiles. For purposes of classification, the authors operationally defined small indeterminate groups that were considered too close to classify (i.e., ±5T of the cut scores). With indeterminate cases removed, the overall classification rates improved modestly. However, the more important finding involved the error rates for the indeterminate group, which exceeded 50%. Directions for further research are discussed.  相似文献   
122.
Rodents solve dual-solution tasks that require navigation to a goal by adopting either a hippocampus-dependent place strategy or a striatum-dependent stimulus-response strategy. A variety of factors, including biological sex and emotional status, influence the choice of learning strategy. In these experiments, we investigated the relationship between learning strategy and anxiety level in male and female rats prior to the onset of puberty, before the activational effects of gonadal hormones influence these processes. In the first experiment, prepubertal male rats categorized as high in trait anxiety at 26days of age exhibited a bias toward stimulus-response strategy at 28days of age, whereas age-matched females exhibited no preference in strategy regardless of anxiety level. In the second experiment, male and female rats were separated from their dams for either 15 or 180min per day during the first 2weeks of life and tested on a battery of anxiety and cognitive tasks between 25 and 29days of age. Prolonged maternal separations for 180min were associated with impaired spatial memory on a Y-maze task in both prepubertal males and females. Furthermore, prolonged maternal separations were linked to elevated anxiety and a bias for stimulus-response strategy in prepubertal males but not females. Alternatively, brief separations from dams for 15min were associated with intact spatial memory, lower levels of anxiety, and no preference for either learning strategy in both sexes. These results provide evidence of sex-specific effects of trait anxiety and early maternal separation on the choice of learning strategy used by prepubertal rodents.  相似文献   
123.
124.
Trait anxiety is an individual-difference variable reflecting variation in state-anxiety elevations resulting from exposure to a stressor. It is usually measured using questionnaire instruments, such as the Spielberger State-Trait Anxiety Inventory (STAI-T). The present research conceptually distinguishes, and independently assesses, two hypothetical dimensions of anxiety vulnerability which, it is argued, could plausibly make independent contributions to variance in trait-anxiety scores. These dimensions are anxiety reactivity, the probability of experiencing an anxiety reaction to a stressor, and anxiety perseveration, the persistence of anxiety symptoms once elicited. Participants were asked three questions about each STAI-T item. The traditional STAI-T question assessed how much of the time this symptom was experienced; the anxiety-reactivity question assessed the probability of experiencing the symptom in response to a stressor; and the anxiety-perseveration question assessed how long the symptom persisted, if elicited. Regression analysis determined that anxiety reactivity and anxiety perseveration scores both accounted for independent variance in trait-anxiety scores. It is argued that models of anxiety vulnerability should seek to differentiate both the causes and the consequences of elevated anxiety reactivity and increased anxiety perseveration. (PsycINFO Database Record (c) 2012 APA, all rights reserved).  相似文献   
125.
A prospective, behavioral high-risk design provided a theoretically guided examination of vulnerability to first onset of bipolar spectrum disorder based on the Behavioral Approach System (BAS) model. Adolescents (ages 14-19) at an "age of risk" for bipolar disorder onset were screened on BAS sensitivity by interviewers blind to current symptoms, lifetime history, and family history of psychopathology. Participants were selected with high versus moderate levels of BAS sensitivity and administered a lifetime diagnostic interview. Those with a bipolar spectrum disorder, psychosis, or hypomanic episode with onset prior to the BAS sensitivity assessment were excluded. High BAS (n = 171) and moderate BAS (n = 119) sensitivity participants in the final sample completed baseline measures of symptoms, goal-setting, and reward responsiveness and were followed prospectively with semistructured diagnostic interviews every 6 months. Consistent with the vulnerability hypothesis of the BAS model of bipolar disorder, high BAS participants had a greater likelihood, and shorter time to onset, of bipolar spectrum disorder than moderate BAS participants across an average of 12.8 months of follow-up (12.9% vs. 4.2%), controlling for baseline depressive and hypomanic symptoms, and family history of bipolar disorder. High reward responsiveness on a behavioral task and ambitious goal-striving for popular fame and financial success (but not impulsivity) also predicted first onset of bipolar spectrum disorder controlling for the covariates and BAS risk group, and ambitious goal-striving partially mediated the BAS risk group effect. We discuss implications of the findings for the BAS model of bipolar disorder and early intervention efforts.  相似文献   
126.
Little longitudinal research has examined progression to more severe bipolar disorders in individuals with "soft" bipolar spectrum conditions. We examine rates and predictors of progression to bipolar I and II diagnoses in a nonpatient sample of college-age participants (n = 201) with high General Behavior Inventory scores and childhood or adolescent onset of "soft" bipolar spectrum disorders followed longitudinally for 4.5 years from the Longitudinal Investigation of Bipolar Spectrum (LIBS) project. Of 57 individuals with initial cyclothymia or bipolar disorder not otherwise specified (BiNOS) diagnoses, 42.1% progressed to a bipolar II diagnosis and 10.5% progressed to a bipolar I diagnosis. Of 144 individuals with initial bipolar II diagnoses, 17.4% progressed to a bipolar I diagnosis. Consistent with hypotheses derived from the clinical literature and the Behavioral Approach System (BAS) model of bipolar disorder, and controlling for relevant variables (length of follow-up, initial depressive and hypomanic symptoms, treatment-seeking, and family history), high BAS sensitivity (especially BAS Fun Seeking) predicted a greater likelihood of progression to bipolar II disorder, whereas early age of onset and high impulsivity predicted a greater likelihood of progression to bipolar I (high BAS sensitivity and Fun-Seeking also predicted progression to bipolar I when family history was not controlled). The interaction of high BAS and high Behavioral Inhibition System (BIS) sensitivities also predicted greater likelihood of progression to bipolar I. We discuss implications of the findings for the bipolar spectrum concept, the BAS model of bipolar disorder, and early intervention efforts.  相似文献   
127.
A number of studies have consistently reported that there is a greater prevalence of mental illness among the most socioeconomically disadvantaged. At the same time, there is evidence that services are not optimally accessed by the most socioeconomically disadvantaged; the most in need of care are also the most likely to have unmet healthcare needs. Of people with mental illnesses, those with severe mental illnesses (SMI) are the most at risk of poverty and the least likely to have optimal care. In the past, specialized community mental health services have been identified as the primary provider for people with SMI. However, there is growing interest in using the primary care setting as the main source of mental health care where both medical treatment and psychotherapy can be accessed. In this paper, we examine factors related to primary care use (and in turn, pharmacologic and psychotherapies) for people who are socioeconomically disadvantaged and who have a SMI.  相似文献   
128.
Effect of contraction intensity [100%, 75%, 50%, and 25% maximum voluntary contraction (MVC)] and movement velocity [0 degrees (isometric)], 50 degrees, 100 degrees, 200 degrees, and 400 degrees/sec. [isovelocities]) on root mean square amplitude (SEMG-RMS) and median frequency power spectrum (SEMG-MNF) of vastus lateralis (VL) surface electromyography was investigated with ten healthy female university students. Peak torque (PT), mean torque (MT), SEMG-MNF, and SEMG-RMS, analyzed using separate repeated-measures analyses of variance (p < or = .05), indicated: (1) an inverse relation between PT and MT and movement velocity, (2) greater SEMG-MNF values during all isovelocity conditions compared with isometric conditions, with highest values occurring at 50 degrees /sec. and at 100% and 75% MVC, and (3) at all contraction intensities SEMG-RMS values were higher during dynamic movements than isometric movements and highest at 200 degrees /sec. Isovelocity contractions were inferred to facilitate a greater recruitment of fast-twitch fibers (via increased SEMG-MNF), which was intensified at 50 degrees /sec., whereas greater overall muscle activation was found at 200 degrees /sec.  相似文献   
129.
The p-median offers an alternative to centroid-based clustering algorithms for identifying unobserved categories. However, existing p-median formulations typically require data aggregation into a single proximity matrix, resulting in masked respondent heterogeneity. A proposed three-way formulation of the p-median problem explicitly considers heterogeneity by identifying groups of individual respondents that perceive similar category structures. Three proposed heuristics for the heterogeneous p-median (HPM) are developed and then illustrated in a consumer psychology context using a sample of undergraduate students who performed a sorting task of major U.S. retailers, as well as a through Monte Carlo analysis.  相似文献   
130.
In two experiments, we investigated the influence of repeated processing in the context of the generation effect. In both experiments, participants studied words once or twice. Once-studied words either were read or were generated from a definition. Twice-studied words were read both times, generated both times, or read once and generated once. Free recall was best (in order of decreasing performance) after generating twice, after generating plus reading, and finally after generating once; any generation was better than purely reading. Recognition showed a similar pattern, except that the benefit of generating twice was not as striking as in recall and that reading plus generating was just as effective as generating twice. The overall pattern of results is accounted for by a simple model in which a second encoding results in a reminding of the first encoding, and this additional encoding supports subsequent recollection. This reminding is, consequently, more effective in recall than in recognition, and it operates in accordance with the principles of transfer-appropriate processing.  相似文献   
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