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961.
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   
962.
Context variability can be defined as the number of preexperimental contexts in which a given concept appears. Following M. Steyvers and K. J. Malmberg's (2003) work, the authors have shown that concepts that are experienced in fewer preexperimental contexts generally are better remembered in episodic memory tasks than concepts that are experienced in a greater number of preexperimental contexts. The purpose of this article is to demonstrate that low context variability confers its memorial advantage because of stronger item-to-list context associations as compared with high context variability. Three experiments that use environmental context changes from study to test demonstrate that the low context variability advantage is eliminated when item-to-list context associations are not available because of environmental changes at test. In addition, the low context variability advantage is eliminated when inward processing at study prevents the formation of item-to-list context associations.  相似文献   
963.
The main determinants of lexical access in speech are considered to be a word's age of acquisition (AoA) and its frequency of occurrence in a speaker's experience. It is unclear whether and how these variables interact, although they are commonly observed to be correlated, for the few studies that address the issue have reported inconsistent findings. An influential view of AoA in lexical processing (Ellis and Lambon Ralph, 2000) predicts stronger frequency effects for items acquired later in life than for those acquired at an early age. Five experiments were designed to investigate the possible interaction of AoA and frequency effects in speech. We found that the interaction between word frequency and AoA was not robust and that, contrary to expectation, the effect of word frequency was greater for words acquired earlier in life than for those acquired later. The implications of our findings are discussed.  相似文献   
964.
There has been a growing interest in using the Internet to access a variety of populations for prevention education and health care. It is not clear that this is viable for homeless and other marginalized populations. The purpose of this study was to describe Internet access and use among a sample of homeless and indigent drug users. A brief questionnaire was developed to assess computer ownership, use, email, and Internet access and use. Participants were recruited through a community-based human immunodeficiency virus (HIV) prevention program. 265 participants completed the questionnaire. While 55% had ever used a computer in their lifetime, only 25% had ever owned a computer, 24% had ever had their own email account, 33% had access to a working computer in the last 30 days, 10% had sent or received email in the last 30 days, and 19% had surfed or accessed information on the Internet in the last 30 days. Logistic regression predicting lifetime use of a computer showed predictive factors of having completed high school (Odds Ratio [OR] = 4.5; 95% Confidence Interval [CI] = 2.41, 8.38) and number of days used amphetamines in the last 30 days, per 5 days of use (OR = 1.64; 95% CI = 1.18, 2.27). Inversely related were age, per 5 years of age (OR = 0.78; 95% CI = 0.65, 0.93) and number of days used marijuana in the last 30 days, per 5 days of use (OR = 0.97; 95% CI = 0.76, 0.99). Very low access and usage suggest that Internet-based public health education models be reexamined for this population. The association with amphetamine use may indicate a facilitating effect of amphetamine by heightening awareness and increasing wakefulness.  相似文献   
965.
Three studies explored the hypothesis that implicit measures of prejudice can tap negative, yet egalitarian associations. In Study 1, automatically associating African Americans with oppression predicted greater automatic prejudice. In Studies 2 and 3, classically conditioning associations between the novel group Noffians and words like oppressed, maltreated, and victimized led to greater automatic prejudice against Noffians. Results suggest that White Americans’ negative automatic associations with African Americans may partly result from associating members of low status groups with unfair circumstances. Because automatic associations predict prejudiced behaviors, the burden of proof is on those wishing to argue that egalitarian negative associations complicate the assessment of automatic attitudes rather than contribute to prejudiced responses. Discussion focuses on the implications of egalitarian negative associations for the theory and measurement of automatic prejudice.  相似文献   
966.
Rather than embracing the notion that contextualism requires purely qualitative methodologies, Westerman and Yanchar argue that there is a place for quantification in post-positivist research. Both authors provide compelling arguments for this position. From our cognitive developmental perspective, we see this as a move toward a new level of integration in psychology. Whereas reactive shifts between positivist quantification and radical contextualism exemplify the kind of pendulum swing we see in individual development immediately before the emergence of a new developmental level, the moves suggested by Westerman and Yanchar are in the direction of a qualitative shift—a new level of differentiation and integration. We argue that the arguments put forward by Westerman and Yanchar do not quite achieve consolidation at this new level, because they remain embedded in a post-positivist contextualism that demands an a priori rejection of psychological universals and strong forms of quantification. In our view, consolidation at this new level requires a shift to a problem-focused methodological pluralism that assimilates a wide range of methodological approaches, critiques them, and adapts them in light of the problems researchers seek to solve.  相似文献   
967.
968.
General catastrophic thinking styles about uncomfortable bodily sensations may predispose the development of common health pathologies, such as persistent headache. The purpose of this research was to explore the relationships between the Pain Catastrophizing (PC) Scale and Anxiety Sensitivity (AS) Index, which measure tendencies to catastrophize pain- and anxiety-related somatic sensations, respectively. A non-clinical sample completed the PC Scale, AS Index, and health outcome questionnaires regarding headache (n = 1018). Results revealed that: (i) AS and PC are empirically separate constructs; (ii) the overlap between PC and AS lies within the domain of fearing physical catastrophe; (iii) AS independently predicts weekly headache, headache pain intensity, and the number of a wide range of physical symptoms associated with headache; and (iv) PC independently predicts the presence of weekly headache. Limitations and implications of this research, as well as recommendations for future research directions are discussed.  相似文献   
969.
We examined the ontogeny of the corticosterone response to (+)-methamphetamine in neonatal rats. In experiment-1, animals were injected with 10 mg/kg of (+)-methamphetamine or saline and plasma corticosterone levels were examined in separate groups 30 or 105 min later on postnatal day (P) 1, 3, 5, 7, 9, 11, 13, 15, 17, or 19. The adrenal response to methamphetamine was best described by a U-shaped function with the nadir of corticosterone release occurring between P7 and P13. Experiment-2 was similar except that the effect of four consecutive days of exposure to (+)-methamphetamine (four times daily at 2 h intervals with 10 mg/kg) was assessed with a single final dose early on the fifth day (i.e. P1-5, 3-7, 5-9, 7-11, 9-13, 11-15, 13-17, 15-19). The 30 min corticosterone response after multiple methamphetamine doses was augmented compared to single exposures, with the exception of the two earliest dosing intervals ending on P5 and P7, where the responses were lower. In addition, at 105 min, the levels of corticosterone were attenuated relative to a single drug administration. With the exception of animals receiving methamphetamine from P15 to P19, thymus weights were unaffected. The data demonstrate that (+)-methamphetamine is a robust activator of corticosterone release in developing animals and this release is extensively modified by age and previous drug exposure.  相似文献   
970.
From their own practices, the authors offer insight into potential ethical dilemmas that may frequently develop in an applied psychology setting in which sport psychology is also being practiced. Specific ethical situations offered for the reader's consideration include confidentiality with coaches, administration, parents, and athlete-clients; accountability in ethical billing practices and accurate diagnosing; identification of ethical boundaries in nontraditional practice settings (locker room, field, rink, etc.); and establishment of professional competence as it relates to professional practice and marketing.  相似文献   
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