Pioneering work in the 1940s and 1950s suggested that the concept of chunking might be important in many processes of perception, learning and cognition in humans and animals. We summarize here the major sources of evidence for chunking mechanisms, and consider how such mechanisms have been implemented in computational models of the learning process. We distinguish two forms of chunking: the first deliberate, under strategic control, and goal-oriented; the second automatic, continuous, and linked to perceptual processes. Recent work with discrimination-network (...) computational models of long- and short-term memory (EPAM/CHREST) has produced a diverse range of applications of perceptual chunking. We focus on recent successes in verbal learning, expert memory, language acquisition and learning multiple representations, to illustrate the implementation and use of chunking mechanisms within contemporary models of human learning. (shrink)

Because no single person or group holds knowledge about all aspects of research, mechanisms are needed to support knowledge exchange and engagement. Expertise in the research setting necessarily includes scientific and methodological expertise, but also expertise gained through the experience of participating in research and/or being a recipient of research outcomes. Engagement is, by its nature, reciprocal and relational: the process of engaging research participants, patients, citizens and others brings them closer to the research but also brings the research closer (...) to them. When translating research into practice, engaging the public and other stakeholders is explicitly intended to make the outcomes of translation relevant to its constituency of users. In practice, engagement faces numerous challenges and is often time-consuming, expensive and ‘thorny’ work. We explore the epistemic and ontological considerations and implications of four common critiques of engagement methodologies that contest: representativeness, communication and articulation, impacts and outcome, and democracy. The ECOUTER methodology addresses problems of representation and epistemic foundationalism using a methodology that asks, “How could it be otherwise?” ECOUTER affords the possibility of engagement where spatial and temporal constraints are present, relying on saturation as a method of ‘keeping open’ the possible considerations that might emerge and including reflexive use of qualitative analytic methods. This paper describes the ECOUTER process, focusing on one worked example and detailing lessons learned from four other pilots. ECOUTER uses mind-mapping techniques to ‘open up’ engagement, iteratively and organically. ECOUTER aims to balance the breadth, accessibility and user-determination of the scope of engagement. An ECOUTER exercise comprises four stages: engagement and knowledge exchange; analysis of mindmap contributions; development of a conceptual schema ; and feedback, refinement and development of recommendations. ECOUTER refuses fixed truths but also refuses a fixed nature. Its promise lies in its flexibility, adaptability and openness. ECOUTER will be formed and re-formed by the needs and creativity of those who use it. (shrink)

We suggest that the cerebellum generates sensory or estimates based on outgoing motor commands and sensory feedback. Thus, it is not a motor pattern generator (HOUK et al.) but a predictive system which is intimately involved in motor behavior. This theory may explain the sensitivity of the climbing fibers to both unexpected external events and motor errors (SIMPSON et al.), and we speculate that unusual biophysical properties of the inferior olive might allow the cerebellum to develop multiple asynchronous sensory estimates, (...) [HOUK et al.; SIMPSON et al.; THACH]. (shrink)

Aim To study the views of people in a largely Muslim country, Kuwait, of the acceptability of a life-ending action such as physician-assisted suicide (PAS). Method 330 Kuwaiti university students judged the acceptability of PAS in 36 scenarios composed of all combinations of four factors: the patient's age (35, 60 or 85 years); the level of incurability of the illness (completely incurable vs extremely difficult to cure); the type of suffering (extreme physical pain or complete dependence) and the extent to (...) which the patient requests a life-ending procedure, euthanasia or PAS (no request, some form of request, repeated requests). In all scenarios, the patients were women who were receiving the best possible care. The ratings were subjected to cluster analysis and analyses of variance. Results Five clusters were found. For 44%, PAS was always very unacceptable, no matter what the circumstances. For 23%, it was unacceptable, but less so if the patient was older or requested it repeatedly. For 16%, it was unacceptable if the patient was young but was acceptable if the patient was elderly. For 5%, it was unacceptable if the patient had extreme pain but was acceptable if completely dependent. For 11%, it was unacceptable if the patient did not request it but acceptable if she did. Conclusion The majority of the Kuwaiti university students opposed PAS either categorically or with a slight variation according to circumstances. Nonetheless, a minority approved of PAS in some cases, particularly when the patient was elderly. (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)

Comprehending the origin of marine invertebrate larvae remains a key domain of research for evolutionary biologists, including the repeated origin of direct developmental modes in echinoids. In order to address the latter question, we surveyed existing evidence on relationships of homology between the ectoderm territories of two closely related sea urchin species in the genus Heliocidaris that differ in their developmental mode. Additionally, we explored a recently articulated idea about homology called ‘organizational homology’ (Muller 2003. In: Muller GB, Newman SA, (...) editors. Origination of organismal form: beyond the gene in developmental and evolutionary biology. Cambridge, MA: A Bradford Book, The MIT Press. p 51–69. ) in the context of this specific empirical case study. Applying the perspective of organizational homology to our experimental system of congeneric echinoids has led us to a new hypothesis concerning the ectoderm evolution in these species. The extravestibular ectoderm of the direct developer Heliocidaris erythrogramma is a novel developmental territory that arose as a fusion of the oral and aboral ectoderm territories found in indirect developing echinoids such as Heliocidaris tuberculata. This hypothesis instantiates a theoretical principle concerning the origin of developmental modules, ‘integration’, which has been neglected because the opposite theoretical principle, ‘parcellation’, is more readily observable in events such as gene duplication and divergence (Wagner 1996. Am Zool 36:36–43). J. Exp. Zool. (Mol. Dev. Evol.) 306B:18– 34, 2006. (shrink)

“Tell me," Wittgenstein once asked a friend, "why do people always say, it was natural for man to assume that the sun went round the earth rather than that the earth was rotating?" His friend replied, "Well, obviously because it just looks as though the Sun is going round the Earth." Wittgenstein replied, "Well, what would it have looked like if it had looked as though the Earth was rotating?” What would it have looked like if we looked at all (...) sciences from the viewpoint of Wittgenstein’s philosophy? Wittgenstein is undoubtedly one of the most influential philosophers of the twentieth century. His complex body of work has been analysed by numerous scholars, from mathematicians and physicists, to philosophers, linguists, and beyond. This volume brings together some of his central perspectives as applied to the modern sciences and studies the influence they may have on the thought processes underlying science and on the world view it engenders. The contributions stem from leading scholars in philosophy, mathematics, physics, economics, psychology and human sciences; all of them have written in an accessible style that demands little specialist knowledge, whilst clearly portraying and discussing the deep issues at hand. (shrink)

Polybius in a familiar passage, lists goods moving past Byzantium between the Mediterranean. world and the Black Sea region; among these goods, slaves are accorded a prominent place: …as regards necessities it is an unidsputed fact that the most plentiful supplies and best qualities of of cattle and slaves reach us from the countries lying round the Pontus, while among luxuries the same countries furnish us with an abundance of honey, wax and preserved fish; from the surplus of our countries (...) they take olive-oil and every kind of wine. As for grain, there is give and-take – with them sometimes supplying us when we require it and sometimes importing it from us. (shrink)

The volume presents essays on the philosophical explanation of the relationship between body and soul in antiquity from the Presocratics to Galen. The title of the volume alludes to a phrase found in Plato, Aristotle and Plotinus, referring to aspects of living behaviour involving both body and soul, and is a commonplace in ancient philosophy, dealt with in very different ways by different authors.

Basic disagreements about what makes human life valuable hinder use of the concept of futility to decide whether it is appropriate to continue life support for one in a permanent state of unconsciousness, or to provide intensive medical care to one in the last stages of a terminal illness (the “paradigm cases”). Triage planning (the process of establishing criteria for health care prioritization) is an attractive alternative framework for addressing the paradigm cases. Triage planning permits society to see the cases (...) in the context of diverse moral perspectives, limited resources, and competing health care demands. Furthermore, at least one essential question posed by the paradigm cases is whether treatment is wasteful, and triage planning is a useful model for identifying and eliminating wasteful medical care. The authors describe how triage planning can be implemented to address the paradigm cases, and conclude that it offers one way of moving debate about these cases beyond futility. (shrink)

The larval arms of echinoid plutei are used for locomotion and feeding. They are composed of internal calcite skeletal rods covered by an ectoderm layer bearing a ciliary band. Skeletogenesis includes an autonomous molecular differentiation program in primary mesenchyme cells (PMCs), initiated when PMCs leave the vegetal plate for the blastocoel, and a patterning of the differentiated skeletal units that requires molecular cues from the overlaying ectoderm. The arms represent a larval feature that arose in the echinoid lineage during the (...) Paleozoic and offers a subject for the study of gene co-option in the evolution of novel larval features. We isolated new molecular markers in two closely related but differently developing species, Heliocidaris tuberculata and Heliocidaris erythrogramma. We report the expression of a larval arm-associated ectoderm gene tetraspanin, as well as two new PMC markers, advillin and carbonic anhydrase. Tetraspanin localizes to the animal half of blastula stage H. tuberculata and then undergoes a restriction into the putative oral ectoderm and future location of the postoral arms, where it continues to be expressed at the leading edge of both the postoral and anterolateral arms. In H. erythrogramma, its expression initiates in the animal half of blastulae and expands over the entire ectoderm from gastrulation onward. Advillin and carbonic anhydrase are upregulated in the PMCs postgastrulation and localized to the leading edge of the growing larval arms of H. tuberculata but do not exhibit coordinated expression in H. erythrogramma larvae. The tight spatiotemporal regulation of these genes in H. tuberculata along with other ontogenetic and phylogenetic evidence suggest that pluteus arms are novel larval organs, distinguishable from the processes of skeletogenesis per se. The dissociation of expression control in H. erythrogramma suggest that coordinate gene expression in H. tuberculata evolved as part of the evolution of pluteus arms, and is not required for larval or adult development. (shrink)