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981.
Although children born preterm or low birth weight (PT LBW) are more likely to exhibit behavior problems compared to children born at term, developmental and family processes associated with these problems are unclear. We examined trajectories of maternal depressive symptoms in relation to toddler compliance and behavior problems in families with PT LBW infants. A total of 177 infants (93 boys, 84 girls) and their mothers enrolled in the study during the infant's NICU stay. Data were collected at five time points across 2 years. Assessments of maternal depressive symptoms were conducted at all time points, and toddler compliance and opposition to maternal requests and behavior problems were assessed at 2 years. Toddlers born earlier with more health problems to mothers whose depressive symptoms increased over time exhibited the most opposition to maternal requests during a cleanup task at 24 months, consistent with multiple risk models. Mothers with elevated depression symptoms reported more behavior problems in their toddlers. The study has implications for family‐based early intervention programs seeking to identify PT LBW infants at highest risk for problem behaviors.  相似文献   
982.
983.
Vaesen asks whether goal maintenance and planning ahead are critical for innovative tool use. We suggest that these aptitudes may have an evolutionary foundation in motor planning abilities that span all primate species. Anticipatory effects evidenced in the reaching behaviors of lemurs, tamarins, and rhesus monkeys similarly bear on the evolutionary origins of foresight as it pertains to tool use.  相似文献   
984.
In human and non-human animals the steroid hormones cortisol and testosterone are involved in social aggression and recent studies suggest that these steroids might jointly regulate this behavior. It has been hypothesized that the imbalance between cortisol and testosterone levels is predictive for aggressive psychopathology, with high testosterone to cortisol ratio predisposing to a socially aggressive behavioral style. In this review, we focus on the effects of cortisol and testosterone on human social aggression, as well as on how they might modulate the aggression circuitry of the human brain. Recently, serotonin is hypothesized to differentiate between impulsive and instrumental aggression, and we will briefly review evidence on this hypothesis. The aim of this article is to provide a theoretical framework for the role of steroids and serotonin in impulsive social aggression in humans.  相似文献   
985.
Dominant theories of moral blame require an individual to have caused or intended harm. However, the current four studies demonstrate cases where no harm is caused or intended, yet individuals are nonetheless deemed worthy of blame. Specifically, individuals are judged to be blameworthy when they engage in actions that enable them to benefit from another's misfortune (e.g., betting that a company's stock will decline or that a natural disaster will occur). Evidence is presented suggesting that perceptions of the actor's wicked desires are responsible for this phenomenon. It is argued that these results are consistent with a growing literature demonstrating that moral judgments are often the product of evaluations of character in addition to evaluations of acts.  相似文献   
986.
McClelland??s (1976) power-stress theory proposes that persons high in need for power experience severe stress in the face of actual or anticipated social events that thwart their need to exert control or influence over others, or to achieve recognition for power-oriented behaviors. Guided by McClelland??s theory, we conducted a simulated dating service experiment with college men who scored either high or low on the Picture Story Exercise (PSE) measure of power motivation and later observed a video displaying an interview with a hypothetical dating partner. From among the 203 men who completed the PSE, 96 took part in the experiment. The video presented an 8-min enactment by a young woman who came across either as an assertive feminist or as compliant and agreeable. Electromyographic responses from the corrugator supercilii (frown muscles) fit the premise of McClelland??s power-stress theory, as did scores on the Reysen Likability Scale and the Affective Attitudes Scale.  相似文献   
987.
The purpose of this study was to (1) extend the research findings of decreased muscular force production in grip strength to the lower extremity strength of children with NF1 and (2) to determine if there was a relationship between isometric strength and functional activities in children with NF1. Force production was assessed using a hand held dynamometer (HHD) and a functional task (hopping and jumping) on a force plate. Data from twenty-six children with NF1 were compared to data from 48 typically developing children of similar sex, weight and height. Children with NF1 demonstrated statistically significant lower force production with HHD (p<0.01) during hip extension, but similar force production for knee extension and ankle plantar flexion compared to the control group. A relationship existed between the ground reaction forces at take-off from both hopping and jumping and the force generated from knee extensor strength in the NF1 group. The addition of a functional task to hand held dynamometry is useful for determining a relationship between common clinical measures and functional activities.  相似文献   
988.
Research on working memory has suggested domain-specific components for visual, verbal, and spatial information, and more recently for emotion. Affective working memory has been proposed as the set of processes involved in the maintenance of emotions to guide behaviour. The current study examined the reliability of an emotion maintenance/affective working memory task over two experimental sessions separated by one week. Subjective accuracy based on individual ratings was found to correlate over time and was highest for negatively valenced pictures. Results suggest that this paradigm is a reliable measure of emotion maintenance, underscoring the utility of this measure as an assessment tool for normative and clinical populations.  相似文献   
989.
990.
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