The neural correlates of rapid eye movements (REMs) in sleep are extraordinarily robust; including REM-locked activation in the retrosplenial cortex, the supplementary eye field and areas overlapping cholinergic basal nucleus. The phenomenology of REMs speaks to the notion that perceptual experience in both sleep and wakefulness is a constructive process – in which we generate predictions of sensory inputs and then test those predictions through actively sampling the sensorium with eye movements. On this view, REMs during sleep may index an (...) internalized active sampling or ‘scanning’ of self-generated visual constructs that are not constrained by visual input. If this view is correct, it renders REMs an ideal probe to study consciousness as “an exclusively internal affair” (Metzinger 2009). In other words, REMs offer a probe of active inference – in the sense of predictive coding – when the brain is isolated from the sensorium in virtue of the natural blockade of sensory input during REM sleep. REMs are temporally precise events that enable powerful inferences based on timeseries analyses. As a natural, task-free probe, [REMs] could be used in non-compliant subjects, including infants and animals. In short, REM constitutes a promising probe to study the ontogenetic and phylogenetic development of consciousness and perhaps its abnormal development in schizophrenia and autism, which have been considered in terms of aberrant predictive coding. (shrink)

A unifying theory of general anesthetic-induced unconsciousness must explain the common mechanism through which various anesthetic agents produce unconsciousness. Functional-brain-imaging data obtained from 11 volunteers during general anesthesia showed specific suppression of regional thalamic and midbrain reticular formation activity across two different commonly used volatile agents. These findings are discussed in relation to findings from sleep neurophysiology and the implications of this work for consciousness research. It is hypothesized that the essential common neurophysiologic mechanism underlying anesthetic-induced unconsciousness is, as with (...) sleep-induced unconsciousness, a hyperpolarization block of thalamocortical neurons. A model of anesthetic-induced unconsciousness is introduced to explain how the plethora of effects anesthetics have on cellular functioning ultimately all converge on a single neuroanatomic/neurophysiologic system, thus providing for a unitary physiologic theory of narcosis related to consciousness. (shrink)

One method for investigating the neurobiology of consciousness is to experimentally manipulate consciousness as a variable and then visualize the resultant functional brain changes with advanced imaging techniques. To begin investigation into this area, healthy volunteers underwent positron emission tomography scanning while listening to randomized word lists in both conscious and unconscious conditions. Following anaesthesia, subjects had no explicit memories. Nonetheless, subjects demonstrated implicit memory on a forced-choice test . These subsequent memory scores were correlated with regional brain metabolism measured (...) during encoding. Conscious recall and unconscious recognition memory demonstrated considerable anatomic overlap in correlating significantly with relative glucose metabolism in auditory verbal memory areas. However, only conscious recall correlated with mediodorsal thalamic nucleus activity; unconscious recognition memory did not. These findings suggest that conscious versus unconscious memory distinctions may depend on the presence or absence of correlated thalamic activity, and directly implicate the thalamus in the neurobiology of consciousness. (shrink)

Medium- and high-spin states of Pr-134 were populated using the Cd-116(Na-23, 5n) reaction and studied with the GAMMASPHERE spectrometer. Several new bands have been found in this nucleus, one of them being linked to the previously observed chiral-candidate twin-band structure. The ground state of Pr-134 could be determined through establishing a level structure that connects the two previously known long-lived isomeric states. Unambiguous spin-parity assignments for the excited states could be performed based on the known 2(-) spin-parity of the ground (...) state combined with the present experimental data. Intrinsic single-particle configurations have been assigned to the newly observed bands on the basis of the measured B(M1)/B(E2) ratios, alignments, band-crossing frequencies, bandhead spins, the observed single-particle configurations in the neighboring nuclei, and taking into account the predictions of total Routhian surface and tilted-axis cranking calculations. (shrink)

High-spin states have been studied in Pr-135(59), populated through the Cd-116(Na-23,4n) reaction at 115 MeV, using the Gammasphere gamma-ray spectrometer. The negative-parity yrast band has been significantly extended to spin similar to 45 (h) over bar and excitation energy 21.5 MeV, showing evidence for several rotational alignments. The positive-parity yrast band of Ce-135(58), populated through the p4n channel of this reaction, was also populated to spin similar to 38 (h) over bar and excitation energy 18 MeV. Cranking calculations indicate that (...) these nuclei are soft with respect to the triaxiality parameter gamma and that several competing nuclear shapes occur at high spin. (shrink)

My object in this paper is to suggest a few reflections on some themes in Bentham's work which others as well as I have noted, without perhaps developing them as fully as might with advantage be done. There will be nothing like full development in the limited compass of what is said here, but what is said may at least indicate possible directions for further exploration. The greater part of the paper will be concerned with the notion of natural authority; (...) but I want to begin by taking a broader, though no doubt rather superficial, view of the role in Bentham's thinking of the concepts of ‘nature’ and ‘the natural’. (shrink)

This additional volume offers a revised edition of Lingua , Erasmus’ work on language, its possibilities and the dangers in its use, ending in a praise of the Word of God. Since it deals with the moral implications of language, Erasmus placed it in Ordo IV that comprises works on moral issues.

The object of this article is to examine, with the work of Jeremy Bentham as the principal example, one strand in the complex pattern of European social theory during the second half of the eighteenth century. This was of course the period not only of the American and French revolutions, but of the culmination of the movements of thought constituting what we know as the Enlightenment. Like all great historical episodes, the Enlightenment was both the fulfilment of long-established processes and (...) the inauguration of new processes of which the fulfilment lay in the future. Thus the seminal ideas of seventeenth-century rationalism realized and perhaps exhausted their potentialities in the eighteenth-century Enlightenment. The ideas with which this article is concerned, however—conveniently grouped and labelled as the ideas of utilitarianism—only began to achieve systematic development in these later decades of the eighteenth century. Within that period—during the first half and more of Bentham's long life—attempts to apply those ideas to the solution of social problems met largely with failure and frustration. Yet unrealized potentialities remained, the realization of which was reserved for a time when the world of the philosophes no longer existed. The movements for social and political reform which have played so large a part in modern history since the French Revolution may be judged in widely differing ways; but whatever the verdict, these movements surely cannot be understood without due consideration of that part of their origins which lies in eighteenth-century utilitarianism. (shrink)

In this book, James Lesher presents the Greek texts of all the surviving fragments of Xenophanes' teachings, with an original English translation on facing pages, along with detailed notes and commentaries and a series of essays on the philosophical questions generated by Xenophanes' remarks.

The contributions to this special collection concern issues and problems discussed in or related to the work of Wesley C. Salmon. Salmon has long been noted for his important work in the philosophy of science, which has included research on the interpretation of probability, the nature of explanation, the character of reasoning, the justification of induction, the structure of space/time and the paradoxes of Zeno, to mention only some of the most prominent. During a time of increasing preoccupation with historical (...) and sociological approaches to under standing science (which characterize scientific developments as though they could be adequately analysed from the perspective of political movements, even mistaking the phenomena of conversion for the rational appraisal of scientific theories), Salmon has remained stead fastly devoted to isolating and justifying those normative standards distinguishing science from non-science - especially through the vindi cation of general principles of scientific procedure and the validation of specific examples of scientific theories - without which science itself cannot be (even remotely) adequately understood. In this respect, Salmon exemplifies and strengthens a splendid tradi tion whose most remarkable representatives include Hans Reichenbach, Rudolf Carnap and Carl G. Hempel, all of whom exerted a profound influence upon his own development. (shrink)

Α Ν 0 Ι Ε Ν Τ Α Ν ϋ Μ Ε Ο Ι Ε V Α Ι, ΡΗΙΙ,ΟδΟΡΗΥ ΠΕ \ν III, Ρ - Μ Α Ν 5 Ι Ο Ν ΟΕΝΤΒΕ 5βΠ88 1 II ιηεΐ (1ε δίβυη νβη Ιιοί Βοΐβίδοΐι λ'αΐίοηααΐ ΌΟΟΓ ...

In many theories in contemporary philosophy of mind, attention is constitutively linked to phenomenal consciousness. Ned Block has recently argued that ‘identity crowding’ provides an example of subjects consciously seeing something to which they are unable to attend. Here I examine the reasons that Block gives for thinking that this is a case of a consciously perceived item that we are unable to attend to, and I offer a different interpretation.