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Real-world judgements and decisions often require choosing from an open-ended set of options which cannot be exhaustively considered before a choice is made. Recent work has found that the options people do consider tend to have particular features, such as high historical value. Here, we pursue the idea that option generation during decision making may reflect a more general mechanism for calling things to mind, by which relevant features in a context-appropriate representational space guide what comes to mind. In this paper, we evaluate this proposal primarily based on what comes to mind in different familiar categories. We first introduce an empirical approach for deriving the space of features that people use to represent items in a particular category and for locating the category members that come to mind within that space. We show that in both familiar and ad hoc categories, a category member's location along certain dimensions of the derived feature space predicts its likelihood of coming to mind. Next, we show that category members from these feature space locations come to mind by default in a way that is somewhat impervious to conscious control. We then demonstrate that the extent to which a given dimension is a predictor of what comes to mind within a category is related to how relevant that feature is for representing the category in question, using a novel measure of general feature relevance. Finally, we illustrate the usefulness of this framework in the context of a decision making task. We close with the proposal that people call category members to mind according to their location in representational space, specifically based on the predicted usefulness of considering category members with particular features. [ABSTRACT FROM AUTHOR]

Abstract: Background: There is a global trend, in high resource countries, for delayed childbearing beyond the age of 35. Women of advanced maternal age are considered to be at higher risk of poor maternal and neonatal outcomes. Women''s views and experiences of delayed childbearing are relatively unexplored. Objectives: To gain an understanding of factors influencing women''s decisions to delay childbearing and explore their experiences and perceptions of associated risks. Design: A qualitative phenomenological study. Setting: Greater Manchester, United Kingdom. Participants: Purposive sample of 18 women aged 35 and over in three groups; six women with no children who were not pregnant, six women pregnant with their first child and six women with no children attending a fertility clinic. Methods: Data were collected by in depth semi-structured interviews, managed manually and subjected to thematic analysis. Results: Three main themes were identified; the chapters of life, the need to know, and childbearing being within or beyond women''s control. Women focussed on the need for a stable relationship, being “ready” to have a baby, and acquisition of life experience. Their experiences reflected a lack of awareness of many of the risks associated with pregnancy over age 35 and disbelief that age alone necessarily increased the likelihood of poor outcomes. Women perceived a lack of choice in the timing of when to start a family. Women suggested that although they may have reached a juncture in their lives, at which they felt ready to have a baby, the circumstances in which they found themselves may not support this; factors such as relationship, financial stability, health and fertility, were often outside of their control. Conclusions: Women do not perceive that they have ultimate control when it comes to the timing of childbearing. Health professionals and the media should be aware of the complex interplay of factors surrounding women''s reasons for delaying childbearing. Sensitive information and support should be provided allowing for varying perceptions of risk status. Women may benefit from pre-conception education. [Copyright &y& Elsevier]

Objectives: To identify what factors affect women's' decisions to delay childbearing, and to explore women's' experiences and their perceptions of associated risks. Design: Systematic procedures were used for search strategy, study selection, data extraction and analysis. Findings were synthesised using an approach developed from meta-ethnography. Data sources: We included qualitative papers, not confined to geographical area (1980–2009). Databases included CINAHL, MEDLINE, EMBASE, PsycInfo, ASSIA, MIDIRS, British Nursing Index and the National Research Register. We selected qualitative empirical studies exploring the views and experiences of women of advanced maternal age who were childless or primigravidae with a singleton pregnancy or primiparous. Review methods: Twelve papers fulfilled the selection criteria and were included for synthesis. Results: Women appear to face an issue of ‘informed and uninformed decision making’; those who believe they are informed but may not be, those who are not informed and find out they are at risk once pregnant, and those who are well informed but choose to delay pregnancy anyway. Maternity services could provide information to enable informed choice regarding timing of childbearing. Conclusions: Health professionals need to be mindful of the fact that women delay childbearing for various reasons. A strategy of pre-conception education may be beneficial in informing childbearing decisions. Obstetricians and midwives should be sensitive to the fact that women may not be aware of all the risks associated with delayed childbearing. [Copyright &y& Elsevier]

Abstract: Control of vascular resistance and blood flow in the fetoplacental circulation is incompletely understood. Reactive oxygen species (ROS), physiological and pathophysiological regulators of vascular tone, are elevated in preeclampsia (PE), a disease of pregnancy characterized by increased fetoplacental vascular resistance. We tested the hypothesis that ROS modulate vascular reactivity in placental chorionic plate arteries. Wire myography was used to examine (1) the effects of acute exposure to ROS on arterial function in normal pregnancy and (2) the effects of maternal antioxidant supplementation on arterial reactivity in women at high risk for PE participating in the Vitamins in Pre-eclampsia (VIP) trial. ROS generated by xanthine plus xanthine oxidase enhanced basal tension, vasoconstriction in response to the thromboxane mimetic U46619, and relaxation in response to sodium nitroprusside. Hydrogen peroxide and peroxynitrite increased basal tone and relaxed preconstricted arteries (U44619), respectively. In women at risk for PE, chorionic plate artery constriction in response to U46619 was greater in the women receiving placebo compared to the women supplemented with the antioxidant vitamins C and E. ROS may regulate fetoplacental vascular resistance and blood flow in the short term, and chronic exposure to raised ROS could contribute to elevated fetoplacental vascular resistance in PE and fetal growth restriction (FGR). [Copyright &y& Elsevier]