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181.
An inaction inertia analysis of procrastination was used to generate the prediction that using bonuses to encourage early task completion will have two opposing effects, encouraging early task completion by some but also inducing procrastination for those who miss the bonus. Study 1 showed that the addition of bonuses for early completion produced both of these effects and also led to overall task completion rates that were either equal to (large bonus) or actually less than (medium and small bonuses) those obtained by simply establishing a completion deadline with no bonus. In Study 2, a lottery methodology was used to manipulate the size of a missed bonus for all participants. Even under these conditions of reduced personal responsibility the larger missed bonus led to increased procrastination as predicted by the inaction inertia analysis. Possible mediating processes based on anticipated regret and perceived fairness were discussed. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   
182.
The ability to attend to relevant events and to ignore irrelevant stimuli is crucial to survival. Theories disagree on whether this ability is dependent solely on increased neural activation for relevant items or whether active ignoring can also play a role. The authors examined the active ignoring of stimuli using a preview search procedure, where irrelevant faces appeared prior to relevant house stimuli. They found increased activation in brain regions associated with spatial memory and in content-specific face-processing areas when participants ignored the irrelevant faces. Differences arose even on trials when only previewed faces appeared, and the magnitude of these differences predicted how well faces were ignored in search. Activation associated with active ignoring decreased when a secondary task was imposed during the preview. The data reveal a neural marker for the process of actively ignoring the content and locations of irrelevant stimuli.  相似文献   
183.
Lesbian women of color may seek professional help to find their way through the challenges of being a triple minority. The authors discuss specific issues faced by African American, Asian American, Latina American, and Native American lesbian women, offering guidelines for affirmative practice when working with these women in a counseling context. Mujeres lesbianas de color pueden buscar ayuda profesional para poder navegar los desafíos de estar en una triple minoría. Los autores describen problemas específicos que enfrentan mujeres afro‐americanas, asiático‐americanas, latinoamericanas, e indígenas lesbianas, y ofrecen gufas para prácticas afirmativas cuando se trabaja con estas mujeres en un contexto de consejería.  相似文献   
184.
185.
Repeated exposure to adverse advents (e.g., risky driving) was thought to increase expectations for the recurrence of the event. Community‐based drivers (130 men, 133 women) were given scenarios depicting everyday road events that could be construed as benign, ambiguous, or malign by the degree of perceived provocation. Differences between levels of gender, ethnicity, age, aggressiveness, and provocation were measured by attributions of intent, hostility, and anger. Results showed that, overall, drivers accurately perceived provocation conditions. Hostile attributional biases were not evident among the sample as a whole, but were dependent on level of aggressiveness and provocation. Analysis of self‐reported driving behavior showed that young, aggressive majority group drivers who experience greater aggression on the road also were more likely to take more risks while driving. Controlling for miles driven, gender differences were not found.  相似文献   
186.
We estimated childhood risk of developing selected DSM-IV Disorders, including Attention-Deficit Hyperactivity Disorder (ADHD), Oppositional Defiant Disorder (ODD), and Separation Anxiety Disorder (SAD), in children with prenatal cocaine exposure (PCE). Children were enrolled prospectively at birth (n = 476) with prenatal drug exposures documented by maternal interview, urine and meconium assays. Study participants included 400 African-American children from the birth cohort, 208 cocaine-exposed (CE) and 192 non-cocaine-exposed (NCE), who attended a 5-year follow-up assessment and whose caregiver completed the Computerized Diagnostic Interview Schedule for Children. Under a generalized linear model (logistic link), Fisher’s exact methods were used to estimate the PCE-associated relative risk (RR) of these disorders. Our results indicated a modest but statistically robust elevation of ADHD risk associated with increasing levels of PCE (p < 0.05). Binary comparison of CE versus NCE children indicated no PCE-associated RR. Estimated cumulative incidence proportions among CE children were 2.9% for ADHD (vs 3.1% NCE); 1.4% for SAD (vs 1.6% NCE); and 4.3% for ODD (vs 6.8% NCE). Our findings suggest evidence of increased risk of ADHD (but not ODD or SAD) in relation to an increasing gradient of PCE during gestation.  相似文献   
187.
Constructing a sexual identity is one of the major developmental tasks of adolescence. Applying the Media Practice Model, this study retrospectively examines how self-identifying lesbian, gay, and bisexual (LGB) individuals used media during the commencement of the coming-out process and the effects of media use during this pivotal time of development. Results indicate that the Internet plays a critical role in the development of LGB sexual identities. Heavy users of media during the coming-out process are significantly less likely to communicate openly with their families later in life. However, individuals’ reports of loneliness and self-esteem are not affected. Conclusions suggest that mediated forms of communication can be beneficial for sexual exploration among LGB individuals.  相似文献   
188.
Effects of environmental variables on performance may be mediated by individual stress states. In this study the effects of jet-aircraft engine noise and signal salience on vigilance performance and self-reported stress state were examined. One hundred and ninety-two (96 female and 96 male) participants were randomly assigned to four experimental conditions consisting of 48 participants each resulting from the factorial combination of signal salience (high and low salience signals) and noise (95 dBA intermittent aircraft noise or quiet). Performance metrics and self-reported stress state (Task Engagement, Distress, and Worry) were collected. Performance in the noise conditions was significantly better than in the quiet conditions. Performance in the high salience conditions was significantly better than the low salience conditions. Noise elevated Task Engagement and low signal salience elevated Distress. Moreover, structural equation model analyses were used to examine stress state mediation between the experimental variables and performance. These analyses indicated Engagement mediates between noise and vigilance performance.  相似文献   
189.
The relationship between type of stimulus (numeric and verbal) and type of precocity (mathematical and verbal) was examined in tasks designed to tap three aspects of working memory: encoding, capacity, and manipulation of information. The tasks included semantic categorization, odd-even categorization, recall of five-item lists after semantic categorization, and recall of items in a continuous paired-associates task. Correlations between task performance and the mathematical and verbal portions of the Scholastic Aptitude Test (SAT-M and SAT-V) were computed for gifted youth. There were no sex differences in the performance measures or in the pattern of correlations between performance and SAT scores. The analysis revealed positive relationships between SAT-M scores and numeric categorization latency, recall in the continuous paired-associate task with words and digits, and recall of digit lists. SAT-V scores were related only to word recall in the continuous paired-associate task and recall of word lists. In the working-memory tasks used, mathematical precocity is more strongly related to performance than is verbal precocity. The relationship is especially strong with numeric stimuli, even when the numeric stimuli are simply items to be remembered. The relationship between type of stimulus and type of precocity suggests underlying differences between verbally and mathematically precocious youth in how different types of stimuli are represented in memory.  相似文献   
190.
Sexual reinforcement in the female rat.   总被引:1,自引:0,他引:1       下载免费PDF全文
Sexual reinforcement in the female rat was studied in a preparation that allowed continuous operant responding for access to a male rat leading to intromission. Experiment 1 used a high operant level nose-poke response to test the possible reinforcing effects of some components of access to a male. A simple tone stimulus used as a conditioned reinforcer and two odor stimuli, target male bedding and emulsified preputial gland, were tested. None of these contingent events altered responding above or below operant level. Access to the male, which was always accompanied by intromission, immediately increased response rate when it was made contingent upon the nose-poke response. Performance on fixed-ratio schedules was erratic, and response rate was low in comparison to typical food-reinforced responding. An interresponse-time analysis indicated, however, that some effect of the ratio contingency may have been present. In Experiment 2, several modifications of the procedure were tested with the objective of creating a more tractable preparation for behavior analysis. Response type and the hormone delivery method were changed, and 2 target males were used instead of 1. The latter tripled the average number of reinforcers earned in a single session. Differences between sexual and other reinforcers are discussed in terms of procedural, quantitative, and motivational aspects of the sexual reinforcement procedure.  相似文献   
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