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151.
It is not clear from the literature why, as children develop, there are important increases in memory span, the number of just-presented items that the participant can repeat in the correct serial order. To understand this, some recent results on capacity limits and processing rates were re-analyzed. We first describe results using a conventional measure of performance in immediate memory tasks that is affected by the list length (proportion correct). Next we describe results using a less conventional measure (number correct) that is unaffected by list length under circumstances in which attention to the list during its presentation is curtailed. This measure can estimate an individual's limited-capacity storage ability. Last, we examine measures of spoken response timing that do and do not change with list length. We show that unconventional measures that do not change with list length, but do change with development, are especially useful in assessing basic changes in information processing parameters, including increases in memory capacity and processing speed.  相似文献   
152.
Social psychological research suggests that because of concerns about being perceived in stereotypical ways, people may experience negative affect and diminished attention and cognitive capacity during interracial interactions. The authors discuss this research in relation to therapy and assessment and also offer practical suggestions for ensuring culturally competent professional practice. La investigación en el campo de la psicología social sugiere que, debido a la preocupación por ser percibida de forma estereotipada, la gente puede experimentar sentimientos negativos y un nivel reducido de atención y capacidad cognitiva durante interacciones interraciales. Los autores discuten esta investigación en relación a la terapia y evaluación, y también ofrecen sugerencias prácticas para asegurar una práctica profesional culturalmente competente.  相似文献   
153.
Most research on consumer choice assumes that decisions are usually made by individuals, and that these decisions are based on an individual's personal attitudes, beliefs, and preferences. Yet, much consumer behavior—from joint decisions to individual choices—is directly or indirectly shaped by people with whom we have some relationship. In this target article, we examine how each member in a relationship can affect how consumer decisions are made. After reviewing foundational work in the area, we introduce a powerful and statistically sophisticated methodology to study decisions within relationships—a dyadic framework of decision-making. We then discuss how the study of consumer decisions in relationships can be informed by different theories in the relationships field, including attachment, interdependence, social power, communal/exchange orientations, relationship norms, and evolutionary principles. By building on the seminal foundations of prior joint-decision making research with theories and methods from contemporary relationship science, we hope to facilitate the integration of the consumer and relationships literature to better understand and generate novel hypotheses about consumer decisions in relationships.  相似文献   
154.
The purpose of this study was to examine parents’ attitudes about and patterns of providing financial assistance to their children during college, and how varying levels of parental financial support were related to children’s beliefs (e.g., perceptions of adulthood), behaviors (e.g., work hours, drinking, and drug use), and identity development. The sample consisted of 402 undergraduate students (62% women) recruited from four college sites across the United States (M age = 19.89), and one of their parents (310 mothers and 92 fathers). Using cluster analysis, results suggested four distinct approaches to parental financial involvement and found that emerging adults’ beliefs, behaviors, and identity development differed as a function of parents’ cluster membership. Discussion focuses on implications for emerging adult children whose parents endorse varying levels of financial involvement.  相似文献   
155.
The search for molecules that restrict synaptic plasticity in the brain has focused primarily on sensory systems during early postnatal development, as critical periods for inducing plasticity in sensory regions are easily defined. The recent discovery that Schaffer collateral inputs to hippocampal area CA2 do not readily support canonical activity-dependent long-term potentiation (LTP) serves as a reminder that the capacity for synaptic modification is also regulated anatomically across different brain regions. Hippocampal CA2 shares features with other similarly "LTP-resistant" brain areas in that many of the genes linked to synaptic function and the associated proteins known to restrict synaptic plasticity are expressed there. Add to this a rich complement of receptors and signaling molecules permissive for induction of atypical forms of synaptic potentiation, and area CA2 becomes an ideal model system for studying specific modulators of brain plasticity. Additionally, recent evidence suggests that hippocampal CA2 is instrumental for certain forms of learning, memory, and social behavior, but the links between CA2-enriched molecules and putative CA2-dependent behaviors are only just beginning to be made. In this review, we offer a detailed look at what is currently known about the synaptic plasticity in this important, yet largely overlooked component of the hippocampus and consider how the study of CA2 may provide clues to understanding the molecular signals critical to the modulation of synaptic function in different brain regions and across different stages of development.  相似文献   
156.
Objective: Preclinical models, receptor localization, and genetic linkage data support the role of D4 receptors in the etiology of ADHD. This proof-of-concept study was designed to evaluate MK-0929, a selective D4 receptor antagonist as treatment for adult ADHD. Method: A randomized, double-blind, placebo-controlled, crossover study was conducted in adults with primary ADHD. The primary end point was changed from baseline in total score on the Adult ADHD Investigator Symptom Rating Scale following a 4-week treatment regimen. Additional measures included Clinical Global Impression-Severity Scale, Hospital Anxiety and Depression Scale, and Brown Attention Deficit Disorder Scale and D4 genotype analysis. Results: No statistically significant treatment differences were found between MK-0929 and placebo in any of the primary or secondary assessments. Conclusion: Results from this study suggest that blockade of the D4 receptor alone is not efficacious in the treatment of adult ADHD.  相似文献   
157.
158.
Communal predators may often need to make especially intricate foraging decisions, as a predator's success may depend on the actions of its neighbours. Here,we consider the decisions made by Portia africana, a jumping spider (Salticidae) that preys on other spiders, including Oecobius amboseli (Oecobiidae), a small prey spider that lives under small sheets of silk (nests) on the walls of buildings. P. africana juveniles settle near oecobiid nests and then ambush oecobiids as they leave or enter the nest. Two or more P. africana juveniles sometimes settle at the same nest and, when an oecobiid is captured, the P. africana juveniles may share the meal. We investigated the joining decisions made by na?ve P. africana juveniles. Experiments were based on using lures (dead spiders positioned in lifelike posture) arranged in a series of 17 different scenes defined by the presence/absence of a nest, the lure types present and the configuration of the lures and the nest. Our findings imply that P. africana juveniles make remarkably precise predatory decisions, with the variables that matter including whether a nest is present, the identity of spiders inside and outside a nest and how spiders are positioned relative to each other and the nest.  相似文献   
159.
Maternal expressive styles, based on a combination of positive and negative expressive patterns, were identified at two points in time and related to multiple aspects of preschool children's emotional development. Mother–child pairs from 260 families participated when the children were 3 years old, and 240 participated again at aged 4 years. Expressive styles were identified at age 3 using cluster analysis, replicated at age 4 and examined in relation to children's emotional understanding, expressiveness and regulation. Three expressive styles were identified: high positive/low negative, very low positive/average negative and average positive/very high negative. Cluster membership was stable in 63% of families from age 3 to 4 years; no systematic patterns of change were evident in the remaining families. Expressive style was related to aspects of children's emotional expression at 3 years and to emotion expression and regulation at 4 years. Children's expressiveness and regulation at age 3 were also related to changes in mothers' expressive styles over 1 year. Identifying mothers' expressive styles provides a unique way to understand the potential role of the emotional climates in which preschool‐aged children learn to express and regulate their own emotions. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
160.
ABSTRACT Chronic hyponatremia (CHN) has traditionally been considered asymptomatic. If symptoms are observed, they are often mistakenly attributed to the underlying disorder. However, in recent studies neuropsychological deficits have been associated with CHN. The authors sought to determine the association between CHN and motor deficits. They used previously collected data, and 41 subjects with hyponatremia were included. An exploratory factor analysis with principal component analysis (PCA) was performed (eigenvalues >1.0). Factor scores were generated for each subject based on the resultant PCA factor structure. Finally, partial correlations were computed to measure the degree of association between baseline serum sodium concentration [Na+] and individual neuropsychological factor scores with the effect of age removed. All significance tests were performed using 2-tailed comparisons with alpha level of p ≤ .05. A 3-factor model emerged accounting for 70.17% of the total variance, including 1 factor that loaded primarily with motor speed and reaction time. A significant correlation was observed between this motor factor and serum [Na+] (r = -.477, p = .002). These findings add to previous observations suggesting that CHN is associated with subtle yet harmful motor deficits.  相似文献   
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