Habituation is defined as a decline in responding to a repeated stimulus. After more than eighty years of research, there is an enduring consensus among researchers on the existence of 9-10 behavioral regularities or parameters of habituation. There is no similar agreement, however, on the best approach to explain these facts. In this paper, we demonstrate that the Sometimes Opponent Processes (SOP) model of stimulus processing accurately describes all of these regularities. This model was proposed by Allan Wagner as a (...) quantitative elaboration of Priming Theory, which states that the processing of a stimulus, and therefore its capacity to provoke its response, depends inversely on the degree to which the stimulus is pre-represented in short-term memory. Using computer simulations, we show that all the facts involving within-session effects or short-term habituation might be the result of priming from recent presentations of the stimulus (self-generated priming). The characteristics involving between-sessions effects or long-term habituation would result from the retrieval of the representation of the stimulus from memory by the associated context (associatively-generated priming). (shrink)

The success of assisted reproductive technologies (ARTs) worldwide has led to an accumulation of frozen embryos that are surplus to the reproductive needs of those for whom they were created. In these situations, couples must decide whether to discard them or donate them for scientific research or for use by other infertile couples. While legislation and regulation may limit the decisions that couples make, their decisions are often shaped by their religious beliefs. Unfortunately, health professionals, scientists and policy-makers are often (...) unaware of the way in which faith traditions view ART and decisions concerning the ‘fate’ of surplus embryos. In this paper scholars representing six major religious traditions provide a commentary on a hypothetical case concerning the donation or destruction of excess ART embryos. These commentaries provide a rich account of religious perspectives on the status of the human embryo and an insight into the relevance of faith to health and policy decisions, particularly in reproductive medicine, ART and embryo research. (shrink)

In conclusion, then, we have tried to show that Drug actions can be predicted and described best on a probabilistic basis and information theory offers a suitable framework for such predictions. Drug actions are fundamentally of the all-or-none type involving the choice between two alternatives and these choises are therefore measurable by binary digits. Drug actions are not absolutely but only relatively specific and such specificity can be measured on the basis of information theory by an array of suitable correlation (...) data. Synergisms and antagonisms can best be explained and measured by considering them as intersymbol influences in communications. A theory of drug action based on information theory is more comprehensive and simpler than any theory based on the principles of classical physics and chemistry.However, these conclusions provide only the general basis for future detailed studies of various drug groups which will probably require the collaboration of chemists and pharmacologists as well as biological mathematicians to produce practical results.Der Verfasser bespricht die verschiedenen Probleme der Drogenwirkung und der Reizwirkung im allgemeinen und kommt zu den folgenden Schlussfolgerungen: Die Wirkung der Drogen kann am besten auf Grundlage der Wahrscheinlichkeitstheorie vorhergesagt und beschrieben werden und die mathematische Informationstheorie bietet einen befriedigenden Rahmen für solche Voraussagungen. Drogenwirkungen beruhen im Grunde genommen auf dem „Alles oder Nichts Prinzip”, d.h. sie beruhen auf einer Wahl zwischen zwei Alternativen und diese Wahlen sind als Logarithmen mit der Basis 2 messbar. Drogenwirkungen sind nicht absolut sondern nur relativ spezifisch und diese SpezifizitÄt kann auf Grundlage der Informationstheorie durch eine Matrize gernessen werden die eine Anordnung passender Korrelationsdaten enthÄlt. Synergismen und Antagonismen zwischen verschiedenen Substanzen können am besten dadurch erklÄrt und gemessen werden, dass man sie als gegenseitige Beeinflussung zwischen den eine Mitteilung bildenden Symbolen auffasst. Eine Theorie der Drogenwirkung auf der Informationstheorie basiert, ist umfassender und einfacher als irgend eine andere der die Prinzipien der klassischen Physik und Chemie zugrunde liegen.Jedoch bieten diese Schlussfolgerungen nur die allgemeine Grundlage für zukünftige detaillierte Studien der verschiedenen Drogenklassen und diese Studien werden die Mitarbeit der Chemiker, der Pharmakologen und der mathematisch eingestellten Biologen erfordern.L'auteur discute les divers aspects de l'action des drogues et des stimulus en général et arrive aux conclusions suivantes: La meilleure manière de prédire et de décrire l'action des drogues est celle qui se base sur la théorie des probabilités, et la théorie mathématique des informations et communications offre un cadre satisfaisant pour de telles prédictions. L'action des drogues est essentiellement du type „tout ou rien”, c'es-à-dire qu'un choix entre deux alternatives prend place et ces choix peuvent Être mesurés par des digits binaires. L'action des drogues est charactérisée non pas par une specificité absolue mais seulement relative et cette specificité peut Être mesurée sur base de la théorie des informations par une matrice contenant des données corrélatives convenables. Les synergismes et les antagonismes des substances agissant simultanément peuvent Être expliqués et mesurés en les considérant comme des influences, existantes entre les symboles constituant une communication. Une théorie pharmacodynamique basée sur la théorie des informations est plus compréhensive et plus simple qu'une théorie basée sur les principes de la physique et de la chimie classiques.Toutefois, ces conclusions ne fournissent que la base générale pour des études futures détaillées des diverses classes de substances pharmacologiques, et ces études demanderont la collaboration des chimistes, des pharmacologistes ainsi que des biologistes mathématiciens. (shrink)

Face transplants have been performed, in a small number, since 2005. Popular concern over the morality of the face transplant has tended to focus on the role that one’s face plays in one’s sense of self or one’s personal identity. In order to address this concern, the current paper will explore the significance of face transplants in the light of a theory of the self that draws on symbolic interactionism, narrative theory, and accounts of embodiment. The paper will respond to (...) certain presuppositions concerning personal identity made by Huxtable and Woodley. A theory of the self will be articulated that draws on the work of Merleau-Ponty and G. H. Mead, in order to place embodiment and social interaction centrally to an understanding of self-identity. This will allow an account of the nature of the suffering that a face transplant seeks to remedy, and its worth as an operation, and crucially the impact that it may have on the sense of personal identity of the recipient of the transplant. The conclusion will review the treatment in the context of the prejudices that members of contemporary societies may hold against those with disfigurements. (shrink)

El artículo examina las posibilidades de una lectura naturalista del Sistema del idealismo trascendental (1800) de F. W. J. Schelling. Defiende que en el rechazo de un concepto absolutista de la voluntad y la teoría del surgimiento de la conciencia por medio del reconocimiento recíproco entre seres racionales se encuentra el principio (no desarrollado por Schelling) de una filosofía de la mente materialista no eliminativista plausible. Presento esas doctrinas en el contexto de las reacciones de F. H. Jacobi y J. (...) G. Fichte a las ambiguas consecuencias para el dogmatismo de la crítica kantiana del uso teórico de la razón. (shrink)