Childless elderly: Theoretical perspectives and practical concerns

Almost nothing is concretely known about childless elderly in cross-cultural perspective. Few published papers have appeared on this social category in the West, although childless elders make up (at least) 20% of the population of elderly in many Western nations. Little is known about childless elderly in the Third World. This paper provides some theoretical background to the study of childless elderly and articulates some social policy concerns about them. It suggests that there are five important questions to examine concerning the lives of childless elderly. These include, how childless aged are or are not provided for in societies in which a great deal of the care of the aged is undertaken by children; how kinship functions as a matrix for care; how the increasingly common phenomenon of voluntary childless may give meaning to childlessness in late life; how childlessness fits with such social science models such as the developmental cycle; and, the relationship of this phenomenon to changing opportunities for women. The paper further examines how factors such as fertility, systems of caregiving, the social meaning of childlessness, alternatives to childlessness such as adoption, and educational and economic opportunities may affect the lives of childless elders.     

Shifting Perspectives in Recovery: Feminist-Informed Relationship Groups for Male Addicts

Addiction distorts relationships. To reduce the risk of relapse, a healthier relationship must emerge in sobriety. In this article, we present a group therapy curriculum that addresses life and relationship issues for men in recovery, incorporating a feminist-informed perspective to challenge viewing women as objects and themselves as invulnerable. In twice-weekly sessions over 4 weeks, groups of men are encouraged to examine how to find balance in their lives, to challenge their views of intimate sexual relationships, to learn how relationships impact relapse risk, to confirm their roles and responsibilities as men, and to support each other in their efforts to change. Although developed for delivery in a 28-day inpatient treatment facility, the curriculum is compatible with outpatient programs. A feminist-informed, systemic perspective is important because the addict's relationships as well as the addict must change to maintain recovery.     

Implementation: the need for a contextual approach to the implementation of musculoskeletal guidelines

This chapter focuses on how strategies to reduce the burden of musculoskeletal disease might be used to inform the development of best clinical practice, public behaviour and health policy. We review what is known about how to modify clinical practice and public behaviour and the effectiveness of a range of interventions that seek to achieve change. From a health policy perspective we examine how those who produce evidence can be linked with decision-makers and how evidence can be used to answer key questions that are pertinent to policy-makers. We argue that implementation strategies need to be targeted to meet the particular contextual constraints and opportunities found within the specific clinical field, policy domain or public setting, but that research is needed to establish the cost and clinical effectiveness of more complex implementation strategies and the financial impact of changing public policy.     

Space-time thermodynamics of the glass transition

We consider the probability distribution for fluctuations in dynamical action and similar quantities related to dynamic heterogeneity. We argue that the so-called "glass transition" is a manifestation of low action tails in these distributions where the entropy of trajectory space is subextensive in time. These low action tails are a consequence of dynamic heterogeneity and an indication of phase coexistence in trajectory space. The glass transition, where the system falls out of equilibrium, is then an order-disorder phenomenon in space-time occurring at a temperature T(g), which is a weak function of measurement time. We illustrate our perspective ideas with facilitated lattice models and note how these ideas apply more generally.     

Equity theory and fair inequality: A neuroeconomic study

The present paper reports results from, to our knowledge, the first study designed to examine the neuronal responses to income inequality in situations in which individuals have made different contributions in terms of work effort. We conducted an experiment that included a prescanning phase in which the participants earned money by working, and a neuronal scanning phase in which we examined how the brain responded when the participants evaluated different distributions of their earnings. We provide causal evidence for the relative contribution of work effort being crucial for understanding the hemodynamic response in the brain to inequality. We found a significant hemodynamic response in the striatum to deviations from the distribution of income that was proportional to work effort, but found no effect of deviations from the equal distribution of income. We also observed a striking correlation between the hemodynamic response in the striatum and the self-reported evaluation of the income distributions. Our results provide, to our knowledge, the first set of neuronal evidence for equity theory and suggest that people distinguish between fair and unfair inequalities.The study of inequality, its sources and consequences, has been a core issue in all of the social sciences and in the philosophical literature on distributive justice. Important normative theories have argued that income inequalities are inherently unfair (1), whereas other theories, in particular libertarianism and liberal egalitarian theories of justice (2–5), argue that income inequalities can be fair if they reflect morally relevant differences. This theoretical debate is mirrored in the political debate on tax, welfare, and health policies, where a key question is whether some inequalities should be accepted as fair. In particular, a core issue in the design of tax and welfare policies is how to handle income inequalities caused by differences in work effort, productivity, or risk-taking. Similar issues arise in the discussion of how to handle inequalities in health due to lifestyle choices. Moreover, in the private sector, heated debates about the fairness of workplace inequalities in earnings are common (6).Preferences for income distribution have been extensively studied in both controlled economic experiments and surveys, and the nature of such preferences has become one of the major questions in behavioral research in social psychology and economics. Important papers in behavioral economics have studied how people respond to different income distributions and have documented, using economic experiments, that people dislike unequal outcomes and are willing to make a tradeoff between their own income and equality (7–9). An extensive and influential literature on equity theory in social psychology has studied how perceptions of fairness in social situations depend on the relationship between input and output. The main result reported in this literature is that people find it fair that the income (output) of a person is in proportion to the work effort (input), and that they dislike deviations from a proportional distribution (10–12). In line with equity theory, more recent papers in behavioral economics, studying distributive behavior in situations in which people have earned the money being distributed, have found that the majority of people accept income inequalities as fair if the inequalities correspond to differences in contributions (13–17). Thus, there is evidence suggesting that people are averse both to deviations from an equal income distribution and to deviations from an income distribution in proportion to work effort.An important neuroeconomic study by Tricomi et al. (18) provided suggestive neuronal evidence of inequality aversion. There is, however, no direct neural evidence of how the brain evaluates an income distribution in situations in which people have made different contributions in terms of work effort. The present paper reports from, to our knowledge, the first neuroimaging study designed to examine how the brain responds to the distribution of income in such situations. As such, it is also, to our knowledge, the first study to examine the neuronal basis for equity theory. We focus on two main questions. First, we examine whether a person’s contribution in terms of work effort affects the way in which the brain’s reward system responds to different income distributions. Addressing this question also allows us to examine how the brain’s reward system responds to deviations from a proportional income distribution, and to compare this response with the response to deviations from an equal income distribution and to an increase in own income. Second, we study how the hemodynamic response in the brain to distributions of earned income correlates with the self-reported evaluations of the same income distributions.To address these questions, we designed an experiment with two phases: a prescanning phase, in which the participants earned money by working on a real-effort task, and a scanning phase, in which we used functional magnetic resonance imaging (fMRI) to examine how different regions of the brain responded when the participants evaluated different distributions of their earnings. The participants were 47 male students from the Norwegian School of Economics.In the prescanning phase of the experiment, each participant was randomly assigned to work on repetitive office work, stuffing envelopes, and entering records into a database, for a specific length of time. Roughly half of the participants (23 subjects) were randomly assigned to work for 60 min, whereas the remaining participants were randomly assigned to work for either 30 or 90 min (12 subjects in each group). All participants were told that their earnings would be based on an hourly wage of 500 Norwegian kroner (NOK) (∼US$85), but that a random process could interfere so that their final payment would not necessarily be the same as their earnings.In the scanning phase, the participants were matched with another participant, each pair worked for 120 min in total, and the sum of their earnings was 1,000 NOK. We had three conditions that differed only with respect to how much the participant in the scanner had contributed in terms of work effort. In the 30:90 condition, the participant in the scanner had worked for 30 min and was matched with someone who had worked 90 min. Participants in the 60:60 condition had worked for 60 min and were matched with someone who had also worked for 60 min, and the participant in the 90:30 condition had worked 90 min and was matched with someone who had worked 30 min. For the participant in the scanner, the share of total work effort in the three conditions was thus either 25%, 50%, or 75% depending on the condition.While inside the MR scanner, the participants rated a sequence of 51 possible distributions of the total earnings on a scale that ranged from very bad (−5) to very good (+5). How much each participant in the pair had contributed in terms of work effort and earnings was common knowledge. Interspersed with the rating trials were 30 control trials. In the control trials, no income distribution was shown and the task of the participants was only to tick off a specific number on the rating scale. The control trials allowed us to distinguish between the neuronal response that resulted from motor and visual stimulation when ticking off a number on the rating scale and the neuronal response that resulted from the subjective evaluation of an income distribution.A key feature of the design was that participants who disliked deviations from a proportional income distribution would respond differently to an increase in own income depending on which condition they were in. For such participants, an increase in own income beyond 250 NOK would have two counteracting effects in the 30:90 condition: they would like getting more money for themselves, but they would dislike the increase in the deviation from a proportional income distribution. For a participant in the 90:30 condition, however, an increase in their own income would result in both more money for themselves and a reduction in the deviation from a proportional income distribution, as long as their own income was below 750 NOK. We would therefore predict that participants in the 90:30 condition valued an increase in own income more than did participants in the 30:90 condition for own income ranging between 250 and 750 NOK (Prediction 1). Similarly, we would predict that participants in the 60:60 condition valued an increase in own income more than did those in the 30:90 condition in the interval between 250 and 500 NOK (Prediction 2), and that they valued an increase in own income less than did those in the 90:30 condition in the interval between 500 and 750 NOK (Prediction 3).     

Text messaging for HIV prevention with young Black men: formative research and campaign development

This article describes the formative research and campaign development for a pilot study to test the feasibility of using cell phone text messaging to promote HIV prevention for young African-American men. We conducted six focus groups with Black men aged 16-20 (N=43) in order to obtain feedback on the campaign content and how best to convey sexual health information via text message using cell phones. We present three main findings: (1) the participants' ideas for conducting this research and how to structure our campaign design; (2) how we broadened our theoretical perspective from an individual focus to an empowerment and social capital focus in order to best communicate a culturally relevant program; and (3) the young adult's specific suggestions for how best to operationalize theoretical constructs related to empowerment and social capital. We found that young Black men were receptive to the idea of receiving text messages for an HIV prevention campaign. As technology proliferates, this work offers specific ideas for how to capitalize on new technological modalities to deliver important communications on prevention.     

Classification images reveal decision variables and strategies in forced choice tasks

Despite decades of research, there is still uncertainty about how people make simple decisions about perceptual stimuli. Most theories assume that perceptual decisions are based on decision variables, which are internal variables that encode task-relevant information. However, decision variables are usually considered to be theoretical constructs that cannot be measured directly, and this often makes it difficult to test theories of perceptual decision making. Here we show how to measure decision variables on individual trials, and we use these measurements to test theories of perceptual decision making more directly than has previously been possible. We measure classification images, which are estimates of templates that observers use to extract information from stimuli. We then calculate the dot product of these classification images with the stimuli to estimate observers'' decision variables. Finally, we reconstruct each observer''s “decision space,” a map that shows the probability of the observer’s responses for all values of the decision variables. We use this method to examine decision strategies in two-alternative forced choice (2AFC) tasks, for which there are several competing models. In one experiment, the resulting decision spaces support the difference model, a classic theory of 2AFC decisions. In a second experiment, we find unexpected decision spaces that are not predicted by standard models of 2AFC decisions, and that suggest intrinsic uncertainty or soft thresholding. These experiments give new evidence regarding observers’ strategies in 2AFC tasks, and they show how measuring decision variables can answer long-standing questions about perceptual decision making.Many current questions about human cognition are related to how people make decisions, including decisions based on perceptual information. For example, how do we decide whether a search target is present in a cluttered display? How do we decide when to respond in a task where both speed and accuracy are important? How do we judge which of two signals is present in a discrimination task?Most theories of perceptual decision making rely on the notion of a decision variable, a quantity that the observer calculates from the stimulus to summarize task-relevant information, e.g., the probability that a faint signal is present in a detection task (1). Some theories of decision making are very simple, e.g., the observer gives one response if the decision variable is greater than a fixed criterion, and another response if the decision variable is less than the criterion. Other theories use more complex decision rules. Testing theories of decision making would be much easier if we had access to observers’ decision variables, but these are usually thought of as theoretical constructs that cannot be measured psychophysically. Here we show that in some tasks, it is possible to estimate decision variables on individual trials, and this provides a very direct way of testing theories of perceptual decision making. We use this method to examine the long-standing question of how people make decisions in two-alternative forced choice (2AFC) tasks.     

Alter(n)sbilder und Diskurse des Alter(n)s

Up to now, images of ageing are considered unilaterally from an individualising perspective in which the cause for negative images as well as the starting point for potential change is localised in cognitive attitude patterns. In this contribution we plead for a conceptual extension of the research on images of ageing which also encloses societal discourses and body images. Images and discourses of ageing and associated ideas of man also reflect the intentions and images of social interest groups. Hence, an important research assignment should be to examine existing images and discourses of ageing critical for their ideological, cultural and societal implications.     

Delving below the surface

There is increasing evidence that racial and ethnic minority patients receive lower quality interpersonal care than white patients. Therapeutic relationships constitute the interpersonal milieu in which patients are diagnosed, given treatment recommendations, and referred for tests, procedures, or care by consultants in the health care system. This paper provides a review and perspective on the literature that explores the role of relationships and social interactions across racial and ethnic differences in health care. First, we examine the social and historical context for examining differences in interpersonal treatment in health care along racial and ethnic lines. Second, we discuss selected studies that examine how race and ethnicity influence clinician-patient relationships. While less is known about how race and ethnicity influence clinician-community, clinician-clinician, and clinician-self relationships, we briefly examine the potential roles of these relationships in overcoming disparities in health care. Finally, we suggest directions for future research on racial and ethnic health care disparities that uses a relationship-centered paradigm.     

Delving Below the Surface

There is increasing evidence that racial and ethnic minority patients receive lower quality interpersonal care than white patients. Therapeutic relationships constitute the interpersonal milieu in which patients are diagnosed, given treatment recommendations, and referred for tests, procedures, or care by consultants in the health care system. This paper provides a review and perspective on the literature that explores the role of relationships and social interactions across racial and ethnic differences in health care. First, we examine the social and historical context for examining differences in interpersonal treatment in health care along racial and ethnic lines. Second, we discuss selected studies that examine how race and ethnicity influence clinician-patient relationships. While less is known about how race and ethnicity influence clinician-community, clinician-clinician, and clinician-self relationships, we briefly examine the potential roles of these relationships in overcoming disparities in health care. Finally, we suggest directions for future research on racial and ethnic health care disparities that uses a relationship-centered paradigm.     

Delving below the surface. Understanding how race and ethnicity influence relationships in health care

There is increasing evidence that racial and ethnic minority patients receive lower quality interpersonal care than white patients. Therapeutic relationships constitute the interpersonal milieu in which patients are diagnosed, given treatment recommendations, and referred for tests, procedures, or care by consultants in the health care system. This paper provides a review and perspective on the literature that explores the role of relationships and social interactions across racial and ethnic differences in health care. First, we examine the social and historical context for examining differences in interpersonal treatment in health care along racial and ethnic lines. Second, we discuss selected studies that examine how race and ethnicity influence clinician-patient relationships. While less is known about how race and ethnicity influence clinician-community, clinician-clinician, and clinician-self relationships, we briefly examine the potential roles of these relationships in overcoming disparities in health care. Finally, we suggest directions for future research on racial and ethnic health care disparities that uses a relationship-centered paradigm.     

Rewarding medicine: good doctors and good behavior

Many patients think that there are shortcomings in the ethical dimensions of patient care, and research supports their view. In this issue of Annals, Erde suggests that physicians' incomes should depend on patients' assessments of their ethical behavior in much the same way that waiters' incomes depend on patrons' tips. Although Erde's solution is satiric, the problem is a serious one. The experiences and perspectives of patients regarding their own illness are undervalued by physicians. A truly patient-centered care demands that physicians elicit, understand, and respond to patients' perspectives. Tying physicians' pay to measurements of patient satisfaction is unlikely to dramatically improve the ethical quality of patient care as long as attention to the patient's perspective is seen as peripheral to "good medical care." Rather than relying on a single, easy "fix," we must re-examine all of professional development and practice. We need to choose persons for medical careers who will find patient-centered care rewarding; we need to provide such persons with training and socialization that underscores the value of personalized medicine; and we need to build institutions and systems that facilitate and reinforce patient-centered practice. The best ways to achieve these objectives are as yet unclear, but if we, as physicians, are offended by Erde's "modest proposal," then we must respond by proposing and implementing our own ideas about how patient care can become more humane.     

血吸虫病防治服务中政府治理工具的选择探讨

本文从公共管理学与管理流行病学的视角,结合我国中央政府和地方政府血吸虫病防治实践案例,讨论了血防服务中10种公共物品和服务的提供方式以及7种主要的政府治理工具,指出了政府在政策工具选择中的多元性、复杂性,以及政府对公共卫生政策工具偏好的细微转变,探讨了政府将实质防治目标转化为具体行动的途径和机制。     

Predictive energy landscapes for folding α-helical transmembrane proteins

We explore the hypothesis that the folding landscapes of membrane proteins are funneled once the proteins’ topology within the membrane is established. We extend a protein folding model, the associative memory, water-mediated, structure, and energy model (AWSEM) by adding an implicit membrane potential and reoptimizing the force field to account for the differing nature of the interactions that stabilize proteins within lipid membranes, yielding a model that we call AWSEM-membrane. Once the protein topology is set in the membrane, hydrophobic attractions play a lesser role in finding the native structure, whereas polar–polar attractions are more important than for globular proteins. We examine both the quality of predictions made with AWSEM-membrane when accurate knowledge of the topology and secondary structure is available and the quality of predictions made without such knowledge, instead using bioinformatically inferred topology and secondary structure based on sequence alone. When no major errors are made by the bioinformatic methods used to assign the topology of the transmembrane helices, these two types of structure predictions yield roughly equivalent quality structures. Although the predictive energy landscape is transferable and not structure based, within the correct topological sector we find the landscape is indeed very funneled: Thermodynamic landscape analysis indicates that both the total potential energy and the contact energy decrease as native contacts are formed. Nevertheless the near symmetry of different helical packings with respect to native contact formation can result in multiple packings with nearly equal thermodynamic occupancy, especially at temperatures just below collapse.The folding of globular proteins has come to be well understood starting from Anfinsen’s thermodynamic hypothesis (1), by means of statistical energy landscape theory (2–5) and its principle of minimal frustration. Evolution selects the sequences of most globular proteins so that folding is, by and large, thermodynamically controlled and the landscape is dominated by the interactions between residues that are close together in the folded state, i.e., the native contacts. In vivo folding of α-helical transmembrane proteins differs from the usually autonomous folding of globular proteins in that, during translation, another actor, the translocon, generally assists the nascent chain in either translocating across or integrating peptides into the lipid membrane. Topology, by which we mean the “specification of the number of transmembrane helices and their in and/or out orientations across the membrane” (ref. 6, p. 909), in vivo is thus initially established cotranslationally with few exceptions. Large barriers between alternate topologies once the protein is folded, along with the involvement of the translocon catalyst, suggest a role for kinetic control in folding of α-helical transmembrane proteins. In light of these differences, what aspects of energy landscape theory, based as it is on near-equilibrium statistical physics, can be applied for understanding and predicting membrane protein structures and folding mechanisms?Despite the known differences between globular and membrane protein folding, there is evidence that some of the ideas from energy landscape theory also apply to membrane protein folding. Starting with Khorana’s work (7), numerous α-helical transmembrane proteins have been refolded from a chemically denatured state in vitro (8). This indicates that at least some transmembrane domains may not require the translocon to fold properly. In addition, recent experiments on a few α-helical transmembrane proteins have succeeded in characterizing the structure of transition state ensembles, in a manner like that used for globular proteins. These studies suggest that native contacts are important in the folding nucleus but may not represent the whole story (9, 10). Whether membrane proteins possess energy landscapes as funneled as globular proteins remains an open question. Experimentally, resolving this question is complicated by the fact that the many ways membrane proteins are unfolded also disrupts their membrane environment. One way to circumvent this problem is to use detergent to solubilize the denatured state, but as of yet, it is unknown how closely the resulting folding mechanisms resemble the folding mechanisms in more realistic membrane environments.We address the role of thermodynamic control and funneled landscapes in α-helical transmembrane protein folding once the protein’s overall topology is set by using coarse-grained molecular dynamics simulations to examine the consequences of the principle of minimal frustration for the second stage of membrane protein folding in which the helices arrange into a specific structure. If the landscapes of α-helical transmembrane membrane proteins indeed are funneled, by using a sufficiently large database of α-helical transmembrane protein structures (11), the principle of minimal frustration provides a strategy to learn an energy function potentially capable of folding α-helical transmembrane proteins via molecular dynamics. We explore this strategy in this paper by extending to membrane proteins an associative memory, water-mediated, structure, and energy model (AWSEM) (12), a coarse-grained molecular dynamics Hamiltonian that has been shown to predict globular protein structures to low resolution. Through an energy landscape optimization we learn the parameters of an intramembrane transferable interaction potential and include an implicit membrane potential. In this work we describe these additions to AWSEM, motivate and detail the optimization and learning algorithm, and evaluate the predictive abilities of the newly optimized AWSEM-membrane force field. We then use thermodynamic landscape analysis to quantify how funnel-like the resulting energy landscapes for folding membrane proteins are when conformations are restricted to have a proper topology within the membrane.     

Senility as disintegrated person in Japan

This article focuses upon the intersection of Japanese concepts ofperson, mind and body and ideas about senile dementia. Questions exploredinclude: How do Japanese ideas about person, in terms of the relationship between mind and body, differ from those generally accepted in the Euro-American world? And how do these ideas influence Japanese conceptualizations ofsenility? I argue that gerontologists and others concerned with the treatmentand understanding of senility from a cross-cultural perspective need topay close attention to how the person, as an ontological concept of being,is perceived and constructed in different contexts. The manner in which people indifferent cultures conceptualize the nature of human being will inevitably have asignificant influence on how they perceive and experience senility. The datafor this article were collected during more than two years of ethnographicfieldwork in northern Japan.     

Predictive information in a sensory population

Guiding behavior requires the brain to make predictions about the future values of sensory inputs. Here, we show that efficient predictive computation starts at the earliest stages of the visual system. We compute how much information groups of retinal ganglion cells carry about the future state of their visual inputs and show that nearly every cell in the retina participates in a group of cells for which this predictive information is close to the physical limit set by the statistical structure of the inputs themselves. Groups of cells in the retina carry information about the future state of their own activity, and we show that this information can be compressed further and encoded by downstream predictor neurons that exhibit feature selectivity that would support predictive computations. Efficient representation of predictive information is a candidate principle that can be applied at each stage of neural computation.Almost all neural computations involve making predictions. Whether we are trying to catch prey, avoid predators, or simply move through a complex environment, the data we collect through our senses can guide our actions only to the extent that these data provide information about the future state of the world. Although it is natural to focus on the prediction of rewards (1), prediction is a much broader problem, ranging from the extrapolation of the trajectories of moving objects to the learning of abstract rules that describe the unfolding pattern of events around us (2–4). An essential aspect of the problem in all these forms is that not all features of the past carry predictive power. Because there are costs associated with representing and transmitting information, it is natural to suggest that sensory systems have optimized coding strategies to keep only a limited number of bits of information about the past, ensuring that these bits are maximally informative about the future. This principle can be applied at successive stages of signal processing, as the brain attempts to predict future patterns of neural activity. We explore these ideas in the context of the vertebrate retina, provide evidence for near-optimal coding, and find that this performance cannot be explained by classical models of ganglion cell firing.     

A backbone-based theory of protein folding

Under physiological conditions, a protein undergoes a spontaneous disorder order transition called "folding." The protein polymer is highly flexible when unfolded but adopts its unique native, three-dimensional structure when folded. Current experimental knowledge comes primarily from thermodynamic measurements in solution or the structures of individual molecules, elucidated by either x-ray crystallography or NMR spectroscopy. From the former, we know the enthalpy, entropy, and free energy differences between the folded and unfolded forms of hundreds of proteins under a variety of solvent/cosolvent conditions. From the latter, we know the structures of approximately 35,000 proteins, which are built on scaffolds of hydrogen-bonded structural elements, alpha-helix and beta-sheet. Anfinsen showed that the amino acid sequence alone is sufficient to determine a protein's structure, but the molecular mechanism responsible for self-assembly remains an open question, probably the most fundamental open question in biochemistry. This perspective is a hybrid: partly review, partly proposal. First, we summarize key ideas regarding protein folding developed over the past half-century and culminating in the current mindset. In this view, the energetics of side-chain interactions dominate the folding process, driving the chain to self-organize under folding conditions. Next, having taken stock, we propose an alternative model that inverts the prevailing side-chain/backbone paradigm. Here, the energetics of backbone hydrogen bonds dominate the folding process, with preorganization in the unfolded state. Then, under folding conditions, the resultant fold is selected from a limited repertoire of structural possibilities, each corresponding to a distinct hydrogen-bonded arrangement of alpha-helices and/or strands of beta-sheet.     

The continuity of gerontological themes.

Based on the premise that scientists should periodically examine the history of their ideas and methodologies, this article focuses on the issue of continuity in the evolution of scientific knowledge about aging. Taking a twenty-five-year perspective, selected research questions and priorities in the biomedical, behavioral, and social domains of aging are used to exemplify the continuity of the gerontological knowledge base. This article concludes that there is considerable evidence of continuity, despite the strong influences of changing cohorts of people and external forces that have shaped new ideas and research questions in gerontology.