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161.
Negative mood, depressive symptoms, and major depressive episodes (MDEs) were examined in 179 smokers with a history of major depression in a trial comparing standard smoking cessation treatment to treatment incorporating cognitive-behavioral therapy for depression (CBT-D). Early lapses were associated with relatively large increases in negative mood on quit date. Mood improved in the 2 weeks after quit date among those returning to regular smoking but not among those smoking moderately. Continuous abstinence was associated with short- and long-term reductions in depressive symptoms. MDE incidence during follow-up was 15.3% and was not associated with abstinence. Unexpected was that CBT-D was associated with greater negative mood and depressive symptoms and increased MDE risk. Results suggest complex bidirectional associations between affect and smoking outcomes.  相似文献   
162.
In 2 studies, the antecedents and consequences of "principled objections" to affirmative action (specific, "race-neutral" reasons for opposing the policy) among Whites were examined. In Study 1. data from a probability sample of Los Angeles adults indicated the following: (a) that principled-objection endorsement was driven not merely by race-neutral values but also by dominance-related concerns like racism; (b) that principled objections mediated the effects of group dominance; and (c) that education strengthened-rather than attenuated-the relationship between dominance-related concerns and principled objections. whereas it left the relationship between race-neutral values and the latter essentially unchanged. In Study 2, the education findings were conceptually replicated in a panel study of undergraduates: The completion of additional years of college boosted the correlation between racism and principled objections, whereas it had no effect on the predictive power of conservatism. These results provide support for a general group-dominance approach, which suggests that factors like racism continue to shape White opposition to race-targeted policies.  相似文献   
163.
31 college age men and women who consume less than three caffeinated beverages per week agreed to participate as subjects in research on the effects of acute caffeine intake on low intensity task performance. All subjects performed two randomly administered test conditions: (1) caffeine (5 mg/kg) and (2) placebo on separate visits following an initial 1-hr. orientation visit. Subjects were administered the beverage 30 min. prior to performing 12 separate tests assessing basic mathematics, simple response, logical reasoning, hand-eye coordination, and spatial and assembly skills. The Spielberger State Anxiety test was administered immediately after consuming the test beverage and once again at posttest. Analysis showed that caffeine did not significantly affect performance on all tests with the exception of the peripheral awareness (hand-eye coordination) test on which performance was higher after ingesting caffeine. The placebo treatment produced no effect on state anxiety, which contrasted with a significant rise in anxiety after caffeine consumption. State anxiety values were significantly greater after caffeine treatment relative to the placebo at pretest, and this difference persisted at posttest. These results demonstrated that the dose of caffeine increased scores on state anxiety for individuals who consumed less than three caffeinated beverages weekly but had very little effect on performance of low intensity tasks, except for a hand-eye coordination test involving peripheral awareness. Perhaps longer continuous performance of more demanding tasks would be more sensitive.  相似文献   
164.
165.
The effects of large neighborhoods (neighborhood size) and of higher frequency neighbors (neighborhood frequency) were examined as a function of nonword neighborhood size in lexical decision tasks. According to the multiple read-out model (J. Grainger & A. M. Jacobs, 1996), neighborhood size and neighborhood frequency effects should vary systematically as a function of nonword neighborhood size. In these experiments, the nonword context was more extensively manipulated than in previous studies, providing a more complete test of the model's predictions. In addition, simulations were conducted examining the model's ability to account for the facilitatory neighborhood size and neighborhood frequency effects observed in these experiments. The results suggest that the model overestimates the role of inhibition in the orthographic processing of English words.  相似文献   
166.
Researchers have identified difficulties associated with the use of traditional Minnesota Multiphasic Personality Inventory-2 (MMPI-2; Butcher, Dahlstrom, Graham, Tellegen, & Kaemmer, 1989) validity scales with survivors of traumatic events. A new scale, the Infrequency-Posttraumatic Stress Disorder scale (Fptsd), was created from MMPI-2 items that were infrequently endorsed by 940 male combat veterans presenting for treatment at the posttraumatic stress disorder (PTSD) clinics of 2 Veterans Affairs Medical Centers. A variety of statistical methods were implemented that preliminarily established Fptsd's validity with a validation sample of 323 additional PTSD-diagnosed combat veterans. Results indicate that, relative to previously established validity and overreporting scales (F, Fb, and Fp), Fptsd was significantly less related to psychopathology and distress and better at discriminating simulated from genuinely reported PTSD. Clinical implications are discussed concerning the use of Fptsd to assess disability-seeking veterans suspected of overreporting PTSD symptoms.  相似文献   
167.
Stimulus repetition usually benefits performance. A notable exception is repetition blindness (RB), in which subjects fail to report a repeated stimulus in a rapid serial visual presentation. Theories differ in attributing RB to either perceptual encoding or memory retrieval and to impaired discrimination versus response bias. In the present study, subjects judged whether one or two letters were imbedded in sequences of digits. Unlike previous studies, false guesses of two unrepeated letters were distinguished from false guesses of two repeated letters. When repeated- and unrepeated-letter trials were randomly intermixed (Experiment 1), RB was entirely attributable to response bias. However, when they were separately blocked (Experiments 2 and 3), RB was manifested in discriminability (d'). The results support perceptual-encoding accounts of RB but indicate that effects on discriminability depend on subjects' processing strategies.  相似文献   
168.
The auditory perceptual abilities of male black-capped chickadees (Poecile atricapilla) were examined using an operant go/no-go discrimination among 16 individual vocalizations recorded at 5 m. The birds learned to discriminate about equally well among eight male chickadee fee-bee songs and eight female zebra finch (Taeniopygia guttata) distance calls. These results do not indicate that chickadees have a species-specific advantage in individual recognition for conspecific over heterospecific vocalizations. We then transferred the chickadees to a discrimination of the same songs and calls rerecorded at a moderate distance. These results showed accurate transfer of discrimination from 16 vocalizations recorded at 5 m to novel versions of the same 16 songs and calls rerecorded at 25 m. That is, chickadees recognized individual songs and calls despite degradation produced by rerecording at 25 m. Identifying individual vocalizations despite their transformation by distance cues is here described as a biologically important example of perceptual constancy.  相似文献   
169.
In the first part of this paper we review evidence suggesting that there exists a mechanism that selects input on the basis of its similarity to the required action. This response-based input selection differs from the more established space- and object-based input selection in that it is not constrained by the structure of the input. Our evidence suggests that the two-choice Stroop effect is caused by this response-based selection mechanism. By contrast, it is known that the flanker effect is determined by the space- and object- based selection mechanisms. We explore whether the conflict resolution of the Stroop and flanker tasks is different as well by embedding these two tasks in a PRP (Psychological Refractory Period) paradigm. We show that the Stroop and the PRP effects are additive whereas the flanker and the PRP effects are underadditive, suggesting that the processes in charge of the conflict resolution in the Stroop and the flanker tasks are indeed different. We discuss possible reasons for this difference, and discuss possible ways in which the response-based mechanism can be implemented in information processing models.  相似文献   
170.
Previous monomethod research has found mixed support for nonlinear effects between certain job characteristics (e.g., job autonomy, job complexity) and outcome variables (e.g., job performance). We hypothesized that these weak nonlinear findings may be due to the prevalence of monomethod research that can lead to a lack of complete measurement and/or introduce common methods variance, either of which may mask the true shape of relationships. Using hierarchical regression analyses and a multitrait–multimethod (MTMM) research design, we found strikingly different results between monomethod and MTMM data when considering the relationships between three psychological climate variables and job satisfaction. While the monomethod results mirrored earlier inconclusive findings, the MTMM data indicated that nonlinear equations explained significantly more of the relationship between all three climate dimensions and job satisfaction. These results suggest that the use of MTMM data allows one to more effectively test for nonlinear effects. Furthermore, these nonlinear results suggest that the format of employee questionnaires should probably change from asking how much an employee has of certain constructs to asking does the employee want more or less of these constructs.  相似文献   
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