A role of perirhinal cortex (PrC) in recognition memory for objects has been well established. Contributions of parahippocampal cortex (PhC) to this function, while documented, remain less well understood. Here, we used fMRI to examine whether the organization of item-based recognition memory signals across these two structures is shaped by object category, independent of any difference in representing episodic context. Guided by research suggesting that PhC plays a critical role in processing landmarks, we focused on three categories of objects that (...) differ from each other in their landmark suitability as confirmed with behavioral ratings (buildings > trees > aircraft). Participants made item-based recognition-memory decisions for novel and previously studied objects from these categories, which were matched in accuracy. Multi-voxel pattern classification revealed category-specific item-recognition memory signals along the long axis of PrC and PhC, with no sharp functional boundaries between these structures. Memory signals for buildings were observed in the mid to posterior extent of PhC, signals for trees in anterior to posterior segments of PhC, and signals for aircraft in mid to posterior aspects of PrC and the anterior extent of PhC. Notably, item-based memory signals for the category with highest landmark suitability ratings were observed only in those posterior segments of PhC that also allowed for classification of landmark suitability of objects when memory status was held constant. These findings provide new evidence in support of the notion that item-based memory signals for objects are not limited to PrC, and that the organization of these signals along the longitudinal axis that crosses PrC and PhC can be captured with reference to landmark suitability. (shrink)

We report two experiments in which participants had to judge the time of occurrence of a stimulus relative to a clock. The experiments were based on the control condition used by Libet, Gleason, Wright, and Pearl [Libet, B., Gleason, C. A., Wright, E. W., & Pearl, D. K. . Time of conscious intention to act in relation to onset of cerebral activities : The unconscious initiation of a freely voluntary act. Brain 106, 623–642] to correct for any bias (...) in the estimation of the time at which an endogenous event, the conscious intention to perform a movement, occurred. Participants’ responses were affected systematically by the sensory modality of the stimulus and by the speed of the clock. Such findings demonstrate the variability in judging the time at which an exogenous event occurs and, by extension, suggest that such variability may also apply to the judging the time of occurrence of endogenous events. The reliability of participants’ estimations of when they formed the conscious intention to perform a movement in Libet et al.’s study is therefore questionable. (shrink)

We report two experiments in which participants had to judge the time of occurrence of a stimulus relative to a clock. The experiments were based on the control condition used by Libet, Gleason, Wright, and Pearl [Libet, B., Gleason, C. A., Wright, E. W., & Pearl, D. K. . Time of conscious intention to act in relation to onset of cerebral activities : The unconscious initiation of a freely voluntary act. Brain 106, 623–642] to correct for any bias (...) in the estimation of the time at which an endogenous event, the conscious intention to perform a movement, occurred. Participants’ responses were affected systematically by the sensory modality of the stimulus and by the speed of the clock. Such findings demonstrate the variability in judging the time at which an exogenous event occurs and, by extension, suggest that such variability may also apply to the judging the time of occurrence of endogenous events. The reliability of participants’ estimations of when they formed the conscious intention to perform a movement in Libet et al.’s study is therefore questionable. (shrink)

Current UK legislation is impacting upon the feasibility and cost-effectiveness of medical record-based research aimed at benefiting the NHS and the public heath. Whereas previous commentators have focused on the Data Protection Act 1998, the Health and Social Care Act 2001 is the key legislation for public health researchers wishing to access medical records without written consent. The Act requires researchers to apply to the Patient Information Advisory Group for permission to access medical records without written permission. We present a (...) case study of the work required to obtain the necessary permissions from PIAG in order to conduct a large scale public health research project. In our experience it took eight months to receive permission to access basic identifying information on individuals registered at general practices, and a decision on whether we could access clinical information in medical records without consent took 18 months. Such delays pose near insurmountable difficulties to grant funded research, and in our case £560 000 of public and charitable money was spent on research staff while a large part of their work was prohibited until the third year of a three year grant. We conclude by arguing that many of the current problems could be avoided by returning PIAG’s responsibilities to research ethics committees, and by allowing “opt-out” consent for many public health research projects. (shrink)

Current UK legislation is impacting upon the feasibility and cost-effectiveness of medical record-based research aimed at benefiting the NHS and the public heath. Whereas previous commentators have focused on the Data Protection Act 1998, the Health and Social Care Act 2001 is the key legislation for public health researchers wishing to access medical records without written consent. The Act requires researchers to apply to the Patient Information Advisory Group for permission to access medical records without written permission. We present a (...) case study of the work required to obtain the necessary permissions from PIAG in order to conduct a large scale public health research project. In our experience it took eight months to receive permission to access basic identifying information on individuals registered at general practices, and a decision on whether we could access clinical information in medical records without consent took 18 months. Such delays pose near insurmountable difficulties to grant funded research, and in our case £560 000 of public and charitable money was spent on research staff while a large part of their work was prohibited until the third year of a three year grant. We conclude by arguing that many of the current problems could be avoided by returning PIAG’s responsibilities to research ethics committees, and by allowing “opt-out” consent for many public health research projects. (shrink)

Self-knowledge is the focus of considerable attention from philosophers: Knowing Our Own Minds gives a much-needed overview of current work on the subject, bringing together new essays by leading figures. Knowledge of one's own sensations, desires, intentions, thoughts, beliefs, and other attitudes is characteristically different from other kinds of knowledge: it has greater immediacy, authority, and salience. The contributors examine philosophical questions raised by the distinctive character of self-knowledge, relating it to knowledge of other minds, to rationality and agency, externalist (...) theories of psychological content, and knowledge of language. Together these original, stimulating, and closely interlinked essays demonstrate the special relevance of self-knowledge to a broad range of issues in epistemology, philosophy of mind, and philosophy of language. (shrink)

The Institute of Medicine's report, the American Medical Association's project, the Open Society Institute's and the initiative sponsored by the Robert Wood Johnson Foundation have focused attention on improving the care of dying patients. These efforts include advance care planning and the use of written advance directives. Although previous studies have provided quantitative descriptions of patient preferences for life-sustaining treatment, including those documented in written ADs, to our knowledge open-ended written preferences have not been studied. Studies of these open-ended preferences (...) could highlight issues with respect to quality end-of-life care. The purpose of this study was to explore the open-ended proxy, health, and personal care preferences of people with HIV as expressed in a written AD form. (shrink)

Background:The severity of the Coronavirus pandemic has led to lockdowns in different countries to reduce the spread of the infection. These lockdown restrictions are likely to be detrimental to mental health and well-being in adolescents. Physical activity can be beneficial for mental health and well-being; however, research has yet to examine associations between adolescent physical activity and mental health and well-being during lockdown.Purpose:Examine the effects of adolescent perceived Coronavirus prevalence and fear on mental health and well-being and investigate the extent (...) to which physical activity can be a protective factor against these concerns.Methods:During United Kingdom lockdown restrictions, 165 participants (100 female, aged 13–19) completed an online questionnaire assessing perceived Coronavirus prevalence and fear, physical activity, and indicators of mental health and well-being (stress, anxiety, depression, fatigue, vitality, and perceived health). Separate hierarchical multiple linear regression analyses (with age, gender, perceived Coronavirus prevalence, and fear entered in step 1, and physical activity in step 2) were run to predict each well-being outcome.Results:Regression analyses indicated that in general, while Coronavirus fear was a negative predictor, physical activity was a positive and stronger predictor of enhanced mental health and well-being outcomes.Conclusion:Findings suggest that physical activity during the Coronavirus pandemic can counteract the negative effects of Coronavirus fear on adolescent mental health and well-being. Therefore, physical activity should be promoted during lockdown to support good mental health and well-being. (shrink)

While outcomes for children with T-cell acute lymphoblastic leukemia have improved dramatically, survival rates for patients with relapsed/refractory disease remain dismal. Prior studies indicate that glucocorticoid resistance is more common than resistance to other chemotherapies at relapse. In addition, failure to clear peripheral blasts during a prednisone prophase correlates with an elevated risk of relapse in newly diagnosed patients. Here we show that intrinsic GC resistance is present at diagnosis in early thymic precursor T-ALLs as well as in a subset (...) of non-ETP T-ALLs. GC-resistant non-ETP T-ALLs are characterized by strong induction of JAK/STAT signaling in response to interleukin-7 stimulation. Removing IL7 or inhibiting JAK/STAT signaling sensitizes these T-ALLs, and a subset of ETP T-ALLs, to GCs. The combination of the GC dexamethasone and the JAK1/2 inhibitor ruxolitinib altered the balance between pro- and anti-apoptotic factors in samples with IL7-dependent GC resistance, but not in samples with IL7-independent GC resistance. Together, these data suggest that the addition of ruxolitinib or other inhibitors of IL7 receptor/JAK/STAT signaling may enhance the efficacy of GCs in a biologically defined subset of T-ALL.Leukemia advance online publication, 30 May 2017; doi:10.1038/leu.2017.136. (shrink)

Psychiatric disorders present distinct clinical challenges which are partly attributable to their multifactorial aetiology and the absence of laboratory tests that can be used to confirm diagnosis or predict risk. Psychiatric disorders are highly heritable, but also polygenic, with genetic risk conferred by interactions between thousands of variants of small effect that can be summarized in a polygenic risk score. We discuss four areas in which the use of polygenic risk scores in psychiatric research and clinical contexts could have ethical (...) implications. First, there is concern that clinical use of polygenic risk scores may exacerbate existing health inequities. Second, research findings regarding polygenic risk could be misinterpreted in stigmatising or discriminatory ways. Third, there are concerns associated with testing minors as well as eugenics concerns elicited by prenatal polygenic risk testing. Fourth, potential challenges that could arise with the feedback and interpretation of high polygenic risk for a psychiatric disorder would require consideration. While there would be extensive overlap with the challenges of feeding back genetic findings in general, the potential clinical use of polygenic risk scoring warrants discussion in its own right, given the recency of this possibility. To this end, we discuss how lay interpretations of risk and genetic information could intersect. Consideration of these factors would be necessary for ensuring effective and constructive communication and interpretation of polygenic risk information which, in turn, could have implications for the uptake of any therapeutic recommendations. Recent advances in polygenic risk scoring have major implications for its clinical potential, however, care should be taken to ensure that communication of polygenic risk does not feed into problematic assumptions regarding mental disorders or support reductive interpretations. (shrink)

When the COVID-19 surge hit New York City hospitals, the Division of Medical Ethics at Weill Cornell Medical College, and our affiliated ethics consultation services, faced waves of ethical issues sweeping forward with intensity and urgency. In this article, we describe our experience over an eight-week period (16 March through 10 May 2020), and describe three types of services: clinical ethics consultation (CEC); service practice communications/interventions (SPCI); and organizational ethics advisement (OEA). We tell this narrative through the prism of time, (...) describing the evolution of ethical issues and trends as the pandemic unfolded. We delineate three phases: anticipation and preparation, crisis management, and reflection and adjustment. The first phase focused predominantly on ways to address impending resource shortages and to plan for remote ethics consultation, and CECs focused on code status discussions with surrogates. The second phase was characterized by the dramatic convergence of a rapid increase in the number of critically ill patients, a growing scarcity of resources, and the reassignment/ redeployment of staff outside their specialty areas. The third phase was characterized by the recognition that while the worst of the crisis was waning, its medium- and long-term consequences continued to pose immense challenges. We note that there were times during the crisis that serving in the role of clinical ethics consultant created a sense of dis-ease as novel as the coronavirus itself. In retrospect we learned that our activities far exceeded the familiar terrain of clinical ethics consultation and extended into other spheres of organizational life in novel ways that were unanticipated before this pandemic. To that end, we defined and categorized a middle level of ethics consultation, which we have termed service practice communication intervention (SPCI). This is an underappreciated dimension of the work that ethics consult services are capable of in times of crisis. We believe that the pandemic has revealed the many enduring ways that ethics consultation services can more robustly contribute to the ethical life of their institutions moving forward. (shrink)

Wittgenstein finished part 1 of the _Philosophical Investigations_ in the spring of 1945. From 1946 to 1949 he worked on the philosophy of psychology almost without interruption. The present two-volume work comprises many of his writings over this period. Some of the remarks contained here were culled for part 2 of the _Investigations_; others were set aside and appear in the collection known as Zettel. The great majority, however, although of excellent quality, have hitherto remained unpublished. This bilingual edition of (...) the _Remarks on the Philosophy of Psychology_ presents the first English translation of an essential body of Wittgenstein's work. It elaborates Wittgenstein's views on psychological concepts such as expectation, sensation, knowing how to follow a rule, and knowledge of the sensations of other persons. It also shows strong emphasis on the "anthropological" aspect of Wittgenstein's thought. Philosophers, as well as anthropologists, psychologists, and sociologists will welcome this important publication. (shrink)

Wittgenstein finished part 1 of the _Philosophical Investigations_ in the spring of 1945. From 1946 to 1949 he worked on the philosophy of psychology almost without interruption. The present two-volume work comprises many of his writings over this period. Some of the remarks contained here were culled for part 2 of the _Investigations_; others were set aside and appear in the collection known as Zettel. The great majority, however, although of excellent quality, have hitherto remained unpublished. This bilingual edition of (...) the _Remarks on the Philosophy of Psychology_ presents the first English translation of an essential body of Wittgenstein's work. It elaborates Wittgenstein's views on psychological concepts such as expectation, sensation, knowing how to follow a rule, and knowledge of the sensations of other persons. It also shows strong emphasis on the "anthropological" aspect of Wittgenstein's thought. Philosophers, as well as anthropologists, psychologists, and sociologists will welcome this important publication. (shrink)

Philosophical arguments often assume that the folk tends towards moral objectivism. Although recent psychological studies have indicated that lay persons’ attitudes to morality are best characterized in terms of non-objectivism-leaning pluralism, it has been maintained that the folk may be committed to moral objectivism _implicitly_. Since the studies conducted so far almost exclusively assessed subjects’ metaethical attitudes via explicit cognitions, the strength of this rebuttal remains unclear. The current study attempts to test the folk’s implicit metaethical commitments. We present results (...) of a newly developed Implicit Association Test (IAT) for metaethical attitudes which indicate that the folk generally tend towards moral non-objectivism on the implicit level as well. We discuss implications of this finding for the philosophical debate. (shrink)

Psychiatry is rapidly adopting digital phenotyping and artificial intelligence/machine learning tools to study mental illness based on tracking participants’ locations, online activity, phone and text message usage, heart rate, sleep, physical activity, and more. Existing ethical frameworks for return of individual research results (IRRs) are inadequate to guide researchers for when, if, and how to return this unprecedented number of potentially sensitive results about each participant’s real-world behavior. To address this gap, we convened an interdisciplinary expert working group, supported by (...) a National Institute of Mental Health grant. Building on established guidelines and the emerging norm of returning results in participant-centered research, we present a novel framework specific to the ethical, legal, and social implications of returning IRRs in digital phenotyping research. Our framework offers researchers, clinicians, and Institutional Review Boards (IRBs) urgently needed guidance, and the principles developed here in the context of psychiatry will be readily adaptable to other therapeutic areas. (shrink)

BackgroundPreprint usage is growing rapidly in the life sciences; however, questions remain on the relative quality of preprints when compared to published articles. An objective dimension of quality that is readily measurable is completeness of reporting, as transparency can improve the reader’s ability to independently interpret data and reproduce findings.MethodsIn this observational study, we initially compared independent samples of articles published in bioRxiv and in PubMed-indexed journals in 2016 using a quality of reporting questionnaire. After that, we performed paired comparisons (...) between preprints from bioRxiv to their own peer-reviewed versions in journals.ResultsPeer-reviewed articles had, on average, higher quality of reporting than preprints, although the difference was small, with absolute differences of 5.0% [95% CI 1.4, 8.6] and 4.7% [95% CI 2.4, 7.0] of reported items in the independent samples and paired sample comparison, respectively. There were larger differences favoring peer-reviewed articles in subjective ratings of how clearly titles and abstracts presented the main findings and how easy it was to locate relevant reporting information. Changes in reporting from preprints to peer-reviewed versions did not correlate with the impact factor of the publication venue or with the time lag from bioRxiv to journal publication.ConclusionsOur results suggest that, on average, publication in a peer-reviewed journal is associated with improvement in quality of reporting. They also show that quality of reporting in preprints in the life sciences is within a similar range as that of peer-reviewed articles, albeit slightly lower on average, supporting the idea that preprints should be considered valid scientific contributions. (shrink)

In this consensus report by a diverse group of academics who conduct and/or are concerned about social and behavioral genomics (SBG) research, the authors recount the often‐ugly history of scientific attempts to understand the genetic contributions to human behaviors and social outcomes. They then describe what the current science—including genomewide association studies and polygenic indexes—can and cannot tell us, as well as its risks and potential benefits. They conclude with a discussion of responsible behavior in the context of SBG research. (...) SBG research that compares individuals within a group according to a “sensitive” phenotype requires extra attention to responsible conduct and to responsible communication about the research and its findings. SBG research (1) on sensitive phenotypes that (2) compares two or more groups defined by (a) race, (b) ethnicity, or (c) genetic ancestry (where genetic ancestry could easily be misunderstood as race or ethnicity) requires a compelling justification to be conducted, funded, or published. All authors agree that this justification at least requires a convincing argument that a study's design could yield scientifically valid results; some authors would additionally require the study to have a socially favorable risk‐benefit profile. (shrink)

The rubber hand paradigm is used to create the illusion of self-touch, by having the participant administer stimulation to a prosthetic hand while the Examiner, with an identical stimulus , administers stimulation to the participant’s hand. With synchronous stimulation, participants experience the compelling illusion that they are touching their own hand. In the current study, the robustness of this illusion was assessed using incongruent stimuli. The participant used the index finger of the right hand to administer stimulation to a prosthetic (...) hand while the Examiner used a paintbrush to administer stimulation to the participant’s left hand. The results indicate that this violation of tactile expectations does not diminish the illusion of self-touch. Participants experienced the illusion despite the use of incongruent stimuli, both when vision was precluded and when visual feedback provided clear evidence of the tactile mismatch. (shrink)

The UK launch of the Science Enterprise Challenge in 1999 has stimulated interest in the evolutions of science-based firms and this paper argues that Popper’s seminal diverse contributions to philosophy are directly relevant to them. It begins by commenting on the applications of both Kuhn’s and Popper’s concepts to technological (as against) scientific evolutions. It then suggests how Popper’s approaches are applicable to the development and assessment of new technology within the framework of Freeman’s stakeholders approach. Monsanto’s development of GMOs (...) is used as an illustrative case. (shrink)

MORRIS: But come back to that other kind of fiction, in which the author himself is involved with his works, not merely in writing something for other people but in writing what seems to be necessary to his conscious existence, to his sense of well-being. For such a writer, when he finished with something he finishes with it; he is not left with continuations that he can go on knitting until he runs out of yarn. This conceit reflects my own (...) experience as a writer, relying on the sap that keeps rising, the force that drives the flower, as Dylan Thomas put it. It is plantlike. We put it in the sun and when it doesn't grow, we take it and put it in another room. I don't think of repotting the plant. The plant must make its own way. BOOTH: I like the organic metaphor, but I keep wanting to come back to particular cases to see how you actually work, in literal detail. Even the organic novelist obviously still has the matter of collecting notes, starting a novel, having it fail to go. Let me put a simple question, and move out from there. How many actual novels, whether they ever reach fruition or not, do you have "growing" at a given time? MORRIS: You don't mean simultaneously? BOOTH: I mean actual notes that exist in some kind of manuscript form, starts on a novel, something you are actually working on. MORRIS: It is so unusual for me to have more than one or two things in mind at once that I don't find this a fruitful question. Wright Morris's work as a novelist, essayist, and photographer is examined by prominent critics in Conversations with Wright Morris; the collection, edited by Robert E. Knoll, was published in the spring of 1977 by the University of Nebraska Press. "The Writing of Organic Fiction" is a chapter in that book. Wayne C. Booth's other contributions to Critical Inquiry include "Kenneth Burke's Way of Knowing" ,"Irony and Pity Once Again: Thais Revisited" , "M.H. Abrams: Historian as Critic, Critic as Pluralist" , “'Preserving the Exemplar': Or, How Not to Dig our Own Graves" , "Notes and Exchanges" , "Metaphor as Rhetoric: The Problem of Evaluation" ,"Ten Literal 'Theses" , and, with Robert E. Streeter, W.J.T. Mitchell: "Sheldon Sacks 1930-1979". (shrink)

Peter Abelard (1079–1142 ce) was the most wide‐ranging philosopher of the twelfth century. He quickly established himself as a leading teacher of logic in and near Paris shortly after 1100. After his affair with Heloise, and his subsequent castration, Abelard became a monk, but he returned to teaching in the Paris schools until 1140, when his work was condemned by a Church Council at Sens. His logical writings were based around discussion of the “Old Logic”: Porphyry's Isagoge, aristotle'S Categories and (...) On Interpretation and boethius'S textbook on topical inference. They comprise a freestanding Dialectica (“Logic”; probably c.1116), a set of commentaries (known as the Logica [Ingredientibus], c. 1119) and a later (c. 1125) commentary on the Isagoge (Logica Nostrorum Petititoni Sociorum or Glossulae). In a work Abelard called his Theologia, issued in three main versions (between 1120 and c.1134), he attempted a logical analysis of trinitarian relations and explored the philosophical problems surrounding God's claims to omnipotence and omniscience. The Collationes (“Debates,” also known as “Dialogue between a Christian, a Philosopher and a Jew”; probably c.1130) present a rational investigation into the nature of the highest good, in which the Christian and the Philosopher (who seems to be modeled on a philosopher of pagan antiquity) are remarkably in agreement. The unfinished Scito teipsum (“Know thyself,” also known as the “Ethics”; c.1138) analyses moral action. (shrink)

This edition of Martin Ostwald's revised version of J. B. Skemp's 1952 translation of _Statesman_ includes a new selected bibliography, as well as Ostwald's interpretive introduction, which traces the evolution in Plato's political philosophy from _Republic_ to _Statesman to Laws_--from philosopher-king to royal statesman.

BackgroundFor many decades, the debate on children’s competence to give informed consent in medical settings concentrated on ethical and legal aspects, with little empirical underpinnings. Recently, data from empirical research became available to advance the discussion. It was shown that children’s competence to consent to clinical research could be accurately assessed by the modified MacArthur Competence Assessment Tool for Clinical Research. Age limits for children to be deemed competent to decide on research participation have been studied: generally children of 11.2 (...) years and above were decision-making competent, while children of 9.6 years and younger were not. Age was pointed out to be the key determining factor in children’s competence. In this article we reflect on policy implications of these findings, considering legal, ethical, developmental and clinical perspectives.DiscussionAlthough assessment of children’s competence has a normative character, ethics, law and clinical practice can benefit from research data. The findings may help to do justice to the capacities children possess and challenges they may face when deciding about treatment and research options. We discuss advantages and drawbacks of standardized competence assessment in children on a case-by-case basis compared to application of a fixed age limit, and conclude that a selective implementation of case-by-case competence assessment in specific populations is preferable. We recommend the implementation of age limits based on empirical evidence. Furthermore, we elaborate on a suitable model for informed consent involving children and parents that would do justice to developmental aspects of children and the specific characteristics of the parent-child dyad.SummaryPrevious research outcomes showed that children’s medical decision-making capacities could be operationalized into a standardized assessment instrument. Recommendations for policies include a dual consent procedure, including both child as well as parents, for children from the age of 12 until they reach majority. For children between 10 and 12 years of age, and in case of children older than 12 years in special research populations of mentally compromised patients, we suggest a case-by-case assessment of children’s competence to consent. Since such a dual consent procedure is fundamentally different from a procedure of parental permission and child assent, and would imply a considerable shift regarding some current legislations, practical implications are elaborated. (shrink)

For decades, the discussion on children’s competence to consent to medical issues has concentrated around normative concerns, with little progress in clinical practices. Decision-making competence is an important condition in the informed consent model. In pediatrics, clinicians need to strike a proper balance in order to both protect children’s interests when they are not fully able to do so themselves and to respect their autonomy when they are. Children’s competence to consent, however, is currently not assessed in a standardized way. (...) Moreover, the correlation between competence to give informed consent and age in children has never been systematically investigated, nor do we know which factors exactly contribute to children’s competence. (shrink)

This book is a rich blend of analyses by leading experts from various cultures and disciplines. A compact introduction to a complex field, it illustrates biotechnology's profound impact upon the environment and society. Moreover, it underscores the vital relevance of cultural values. This book empowers readers to more critically assess biotechnology's value and effectiveness within both specific cultural and global contexts.

In this essay I discuss Abraham Joshua Heschel’s influence in the Chinese-reading world by focusing on the growing list of publications about, and translations of, his works in Chinese. By examinin...

This article is part of a For-Discussion-Section of Methods of Information in Medicine about the paper "Biomedical Informatics: We Are What We Publish", written by Peter L. Elkin, Steven H. Brown, and Graham Wright. It is introduced by an editorial. This article contains the combined commentaries invited to independently comment on the Elkin et al. paper. In subsequent issues the discussion can continue through letters to the editor.