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841.
A sudden change applied to a single component can cause its segregation from an ongoing complex tone as a pure-tone-like percept. Three experiments examined whether such pure-tone-like percepts are organized into streams by extending the research of Bregman and Rudnicky (1975). Those authors found that listeners struggled to identify the presentation order of 2 pure-tone targets of different frequency when they were flanked by 2 lower frequency "distractors." Adding a series of matched-frequency "captor" tones, however, improved performance by pulling the distractors into a separate stream from the targets. In the current study, sequences of discrete pure tones were substituted by sequences of brief changes applied to an otherwise constant 1.2-s complex tone. Pure-tone-like percepts were evoked by applying 6-dB increments to individual components of a complex comprising harmonics 1-7 of 300 Hz (Experiment 1) or 0.5-ms changes in interaural time difference to individual components of a log-spaced complex (range 160-905 Hz; Experiment 2). Results were consistent with the earlier study, providing clear evidence that pure-tone-like percepts are organized into streams. Experiment 3 adapted Experiment 1 by presenting a global amplitude increment either synchronous with, or just after, the last captor prior to the 1st distractor. In the former case, for which there was no pure-tone-like percept corresponding to that captor, the captor sequence did not aid performance to the same extent as previously. It is concluded that this change to the captor-tone stream partially resets the stream-formation process, and so the distractors and targets became likely to integrate once more.  相似文献   
842.
Children (N = 157) 4 to 8 years old participated 1 time (single) or 4 times (repeated) in an interactive event. Across each condition, half were questioned a week later about the only or a specific occurrence of the event (depth first) and then about what usually happens. Half were prompted in the reverse order (breadth first). Children with repeated experience who first were asked about what usually happens reported more event-related information overall than those asked about an occurrence first. All children used episodic language when describing an occurrence; however, children with repeated-event experience used episodic language less often when describing what usually happens than did those with a single experience. Accuracy rates did not differ between conditions. Implications for theories of repeated-event memory are discussed.  相似文献   
843.
Predictors of multiple dimensions of spirituality/religiosity (S/R) and adolescents’ preferences for having S/R (e.g., prayer) addressed in hypothetical medical settings were assessed in a sample of urban adolescents with asthma. Of the 151 adolescents (mean age = 15.8, 60% female, 85% African-American), 81% said that they were religious and spiritual, 58% attended religious services in the past month, and 49% prayed daily. In multivariable models, African-American race/ethnicity and having a religious preference were associated with higher levels of S/R (R 2 = 0.07–0.25, P < .05). Adolescents’ preferences for including S/R in the medical setting increased with the severity of the clinical situation (P < .05).  相似文献   
844.
This study examined the relationship between conscientiousness and mortality over 18 years and whether smoking behavior mediated this relationship. We utilized data from the Veterans Affairs Normative Aging Study on 1349 men who completed the Goldberg (1992) adjectival markers of the Big Five. Over the 18-year follow-up, 547 (41%) participants died. Through proportional hazards modeling in a structural equation modeling framework, we found that higher levels of conscientiousness significantly predicted longer life, and that this effect was mediated by current smoking status at baseline. Methodologically, we also demonstrate the effectiveness of using a structural equation modeling framework to evaluate mediation when using a censored outcome such as mortality.  相似文献   
845.
Following two decades of research on non-human animals, there has recently been increased interest in human nonindependent mate choice, namely the ways in which choosing women incorporate information about a man's past or present romantic partners ('model females') into their own assessment of the male. Experimental studies using static facial images have generally found that men receive higher desirability ratings from female raters when presented with attractive (compared to unattractive) model females. This phenomenon has a straightforward evolutionary explanation: the fact that female mate value is more dependent on physical attractiveness compared to male mate value. Furthermore, due to assortative mating for attractiveness, men who are paired with attractive women are more likely to be of high mate value themselves. Here, we also examine the possible relevance of model female cues other than attractiveness (personality and behavioral traits) by presenting video recordings of model females to a set of female raters. The results confirm that the model female's attractiveness is the primary cue. Contrary to some earlier findings in the human and nonhuman literature, we found no evidence that female raters prefer partners of slightly older model females. We conclude by suggesting some promising variations on the present experimental design.  相似文献   
846.
Affect has been identified across numerous research studies to be a vital element in understanding couple relationship processes. Affect has been shown to distinguish between satisfied and dissatisfied couples and to be important in understanding processes leading to relationship dissolution. However, research has not yet uncovered nonverbal indicators that a couple is experiencing negative affect compared to other affective states. In this study we sought to identify specific nonverbal behaviors associated with different affective states. Results suggested that differences in looking-behavior and smiling can be used to identify affect states during couple communication. We outline how the results can aid couples therapy interventions.  相似文献   
847.
Three studies tested the hypothesis that the relation between perceived racial discrimination and substance use reported in previous research is moderated by use of substances as a coping mechanism. Studies 1 and 2 were experimental studies of African American adolescents' and young adults' reactions to a discrimination experience. Results revealed that those who endorsed substance use-as-coping reported more willingness to use substances after experiencing discrimination. Study 3 was a prospective study of the relation between perceived discrimination and substance use over an 8-year period in African American adolescents. Results demonstrated that discrimination is associated with increases in substance use, but only among adolescents who endorse substance use-as-coping. Together, these three studies provide evidence that experiencing discrimination has both short- and long-term detrimental effects on African Americans' substance use, but significantly more so for those who adopt a pattern of using substances as a coping mechanism. (PsycINFO Database Record (c) 2012 APA, all rights reserved).  相似文献   
848.
Significant gaps exist in children’s mental healthcare, and barriers prevent access to existing services. Current federal initiatives call for state governmental agencies to recognize and resolve deficits in their systems of care. Previous work has acknowledged some of the problems in meeting the mental health needs of children within a system of care. This current project sought to discriminate between gaps (e.g., non-existent services) and barriers (e.g., problems that prevent access to existing services) within state mental health care plans. Because acknowledging barriers and gaps in mental health services is a step towards systems improvement, the present project describes how state governments recognize the limits of their children’s mental health care systems. We analyzed state mental health plans submitted to the federal government in applications for block grant funds. Results illustrate that a varied number of gaps and barriers are acknowledged in state plans. Overall, 90% of state plans discussed barriers and 84% of state plans discussed service gaps. The gap most frequently recognized was lack of providers (74%), while lack of funding (52%) was the most common barrier. This project points to some recognition of system limits in the states and reflects potential efforts to create policies for system improvement for children and families.  相似文献   
849.
Abstract

Early aiming adjustments following an online perturbation are made possible by impulse control. This process may unfold even earlier when perturbations impose a greater risk of a costly overshoot error. Participants executed upward and downward aims to mediate the cost of potential errors—downward overshoots require more energy to correct against gravity. On 33% of the trials, texture elements on the aiming surface were shifted following onset to appear congruent or incongruent with the aiming direction, and consequently generate a misperception of the limb moving slower or faster, respectively. Thus, the risk of potential errors could be influenced by the online perturbation (e.g., increased perceived likelihood of overshooting following the incongruent background). Findings indicated greater undershooting for down compared to up, which reflects the principle of movement optimisation. There was also more undershooting for an incongruent compared to congruent background, which is consistent with early online adjustments counter-acting the misperceived limb velocity. However, there were no interactions throughout the movement trajectory. We suggest that while the initial pre-programme considers the cost of potential errors (target direction), early impulse control fails to discriminate the likelihood of these errors occurring following an online perturbation (moving background).  相似文献   
850.
The associative mechanisms responsible for the efficacy of Pavlovian stimuli during first- and second-order conditioning have been extensively studied, but little is known about the representations underlying instrumental conditioned reinforcement. The present study investigated the associative structure underlying conditioned reinforcement, by employing an unconditioned stimulus (US) devaluation procedure on a commonly used instrumental task: the acquisition of a new response with conditioned reinforcement. Whilst US-directed behaviour was abolished following devaluation, the conditioned stimulus acting as a conditioned reinforcer supported the acquisition of instrumental responding. In this preparation then, the conditioned reinforcer appears to be impervious to devaluation of its associated US, suggesting that the underlying representation maintaining behaviour is independent of the current value of the US and may reflect the activation of a central appetitive motivational state.  相似文献   
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