Traditional explanations of multistable visual phenomena (e.g. ambiguous figures, perceptual rivalry) suggest that the basis for spontaneous reversals in perception lies in antagonistic connectivity within the visual system. In this review, we suggest an alternative, albeit speculative. explanation for visual multistability - that spontaneous alternations reflect responses to active, programmed events initiated by brain areas that integrate sensory and non-sensory information to coordinate a diversity of behaviors. Much evidence suggests that perceptual reversals are themselves more closely related to the expression (...) of a behavior than to passive sensory responses: (1) they are initiated spontaneously, often voluntarily, and are influenced by subjective variables such as attention and mood; (2) the alternation process is greatly facilitated with practice and compromised by lesions in non- visual cortical areas; (3) the alternation process has temporal dynamics similar to those of spontaneously initiated behaviors; (4) functional imaging reveals that brain areas associated with a variety of cognitive behaviors are specifically activated when vision becomes unstable. In this scheme, reorganizations of activity throughout the visual cortex, concurrent with perceptual reversals, are initiated by higher, largely non- sensory brain centers. Such direct intervention In the processing of the sensory input by brain structures associated with planning and motor programming might serve an important role in perceptual organization, particularly in aspects related to selective attention. (shrink)

Traditional explanations of multistable visual phenomena (e.g. ambiguous figures, perceptual rivalry) suggest that the basis for spontaneous reversals in perception lies in antagonistic connectivity within the visual system. In this review, we suggest an alternative, albeit speculative, explanation for visual multistability – that spontaneous alternations reflect responses to active, programmed events initiated by brain areas that integrate sensory and non-sensory information to coordinate a diversity of behaviors. Much evidence suggests that perceptual reversals are themselves more closely related to the expression (...) of a behavior than to passive sensory responses: (1) they are initiated spontaneously, often voluntarily, and are influenced by subjective variables such as attention and mood; (2) the alternation process is greatly facilitated with practice and compromised by lesions in non-visual cortical areas; (3) the alternation process has temporal dynamics similar to those of spontaneously initiated behaviors; (4) functional imaging reveals that brain areas associated with a variety of cognitive behaviors are specifically activated when vision becomes unstable. In this scheme, reorganizations of activity throughout the visual cortex, concurrent with perceptual reversals, are initiated by higher, largely non-sensory brain centers. Such direct intervention in the processing of the sensory input by brain structures associated with planning and motor programming might serve an important role in perceptual organization, particularly in aspects related to selective attention. (shrink)

Correspondence should be addressed to David A. Leopold david.leopold@tuebingen.mpg.deDuring the viewing of certain patterns, widely known as ambiguous or puzzle figures, perception lapses into a sequence of spontaneous alternations, switching every few seconds between two or more visual interpretations of the stimulus. Although their nature and origin remain topics of debate, these stochastic switches are generally thought to be the automatic and inevitable consequence of viewing a pattern without a unique solution. We report here that in humans such (...) perceptual alternations can be slowed, and even brought to a standstill, if the visual stimulus is periodically removed from view. We also show, with a visual illusion, that this stabilizing effect hinges on perceptual disappearance rather than on actual removal of the stimulus. These findings indicate that uninterrupted subjective perception of an ambiguous pattern is required for the initiation of the brain-state changes underlying multistable vision.Visual perception involves coordination between sensory sampling of the world and active interpretation of the sensory data. Human perception of objects and scenes is normally stable and robust, but it falters when one is presented with patterns that are inherently ambiguous or contradictory. Under such conditions, vision lapses into a chain of continually alternating percepts, whereby a viable visual interpretation dominates for a few seconds and is then replaced by a rival interpretation. This multistable vision, or 'multistability', is thought to result from destabilization of fundamental visual mechanisms, and has offered valuable insights into how sensory patterns are actively organized and interpreted in the brain1, 2. Despite a great deal of recent research and interest in multistable perception, however, its neurophysiological underpinnings remain poorly understood. Physiological studies have suggested that disambiguation of ambiguous patterns. (shrink)

Understanding how activity in the brain leads to a subjective percept is of great interest to philosophers and neuroscientists alike. In the last years, neurophysiological experiments have approached this problem directly by measuring neural signals in animals as they experience well-defined visual percepts. Stimuli in these studies are often inherently ambiguous, and thus rely upon the subjective report, generally from trained monkeys, to provide a measure of perception. By correlating activity levels in the brain to this report, one can speculate (...) on the role of individual neurons and groups of neurons in the formation and maintenance of a particular percept. However, in order to draw valid conclusions from such experiments, it is critical that the responses accurately and reliably reflect what is perceived. For this reason, a number of behavioural paradigms have been developed to control and evaluate the truthfulness of responses from behaving animals. Here we describe several approaches to optimizing the reliability of a monkey's perceptual report, and argue that their combination provides an invaluable approach in the study of subjective visual perception. (shrink)

Background: Continuous viewing of ambiguous patterns is characterized by wavering perception that alternates between two or more equally valid visual solutions. However, when such patterns are viewed intermittently, either by repetitive presentation or by periodic closing of the eyes, perception can become locked or "frozen" in one configuration for several minutes at a time. One aspect of this stabilization is the possible existence of a perceptual memory that persists during periods in which the ambiguous stimulus is absent. Here, we use (...) a novel paradgim of temporally interleaved ambiguous stimuli to explore the nature of this memory, with particular regard to its potential impact on perceptual organization. Results: We found that the persistence of a perceptual configuration was robust to interposed visual patterns and, further, that at least three ambiguous patterns, when interleaved in time, could undergo parallel, stable time courses. Then, using an interleaved presentation paradigm, we established that the occasional reversal in one pattern could be coupled with that of its interleaved counterpart, and that this coupling was a function of the structural similarity between the patterns. Conclusions: We postulate that the stabilization observed with repetitive presentation of ambiguous patterns can be at least partially accounted for by processes that retain a recent perceptual interpretation, and we speculate that such memory may be important in natural vision. We further propose tha the interleaved paradigm introduced here may be of great value to gauge aspects of stimulus similarity that appeal to particular mechanisms of perceptual organization. (shrink)

The relationship between brain activity and conscious visual experience is central to our understanding of the neural mechanisms underlying perception. Binocular rivalry, where monocular stimuli compete for perceptual dominance, has been previously used to dissociate the constant stimulus from the varying percept. We report here fMRI results from humans experiencing binocular rivalry under a dichoptic stimulation paradigm that consisted of two drifting random dot patterns with different motion coherence. Each pattern had also a different color, which both enhanced rivalry and (...) was used for reporting which of the two patterns was visible at each time. As the perception of the subjects alternated between coherent motion and motion noise, we examined the effect that these alternations had on the strength of the MR signal throughout the brain. Our results demonstrate that motion perception is able to modulate the activity of several of the visual areas which are known to be involved in motion processing. More specifically, in addition to area V5 which showed the strongest modulation, a higher activity during the perception of motion than during the perception of noise was also clearly observed in areas V3A and LOC, and less so in area V3. In previous studies, these areas had been selectively activated by motion stimuli but whether their activity reflects motion perception or not remained unclear; here we show that they are involved in motion perception as well. The present findings therefore suggest a lack of a clear distinction between ?processing? versus ?perceptual? areas in the brain, but rather that the areas involved in the processing of a specific visual attribute are also part of the neuronal network that is collectively responsible for its perceptual representation. (shrink)

Logothetis, N.K.: Single units and conscious vision. Philosophical Transactions of the Royal Society of London Series B-Biological Sciences 353, 1801-1818 (1998) Abstract.

In order to contribute to the consolidation in the field ofPositive Psychology, we reinvestigated the factor structure of top 10 positive emotions of Barbara Fredrickson. Former research in experimental settings resulted in a three-cluster solution, which we tested withexploratoryandconfirmatorymethodology against different factor models. Within our non-experimental data (N= 312), statistical evidence is presented, advocating for a single factor model of the 10 positive emotions. Different possible reasons for the deviating results are discussed, as well as the theoretical significance to various (...) subfields inPositive Psychology(e.g., therapeutical interventions). Furthermore, the special role ofawewithin the study and its implications for further research in the field are discussed. (shrink)

Le dualisme de Kant doit être remplacé par une différenciation plus subtile. L’indéterminisme n’est plus pour nous notion contradictoire du déterminisme ; la norme, individuelle ou sociale, ne doit plus être dépourvue de tout élément empirique. Connexion du déterminisme avec le rationalisme : le « rationalisme interventionniste » prouve l’impossibilité d’un point de vue radical. En un sens modifié, le moment indéterministe demeure et se conserve dans la pensée normative ; même les normes apparemment déterministes de Nietzsche n’en sont pas (...) moins libres. La norme sociale n’est pas possible sans une hiérarchie des connexes, et celle-ci a pour prémisse un pluralisme des sphères ontiques, dont le heurt représente le moment indéterministe. La détermination intégrale, elle, tient, au contraire, de la métaphysique. (shrink)

Excerpt from Histoire de la Philosophie Atomistique La recherche proprement historique des origines de l'atomisme ne peut porter que sur quelques points tres limites ou une formule particuliere de ce systeme semble s'etre spontanement degagee d'un concours de circonstances accidentelles, telles qu'une opposition d'ecoles, une evolution ou une communication de doctrines. Les epoques qui comportent une pareille investigation sont precisement les plus obscures de l'histoire philosophique. Quand on aura distingue a grands traits les antecedents probables de Kanada chez les Hindous, (...) de Leucippe chez les Grecs, des Motecallemin chez les Arabes, de Gassendi au XVIIe siecle, on aura a peu pres epuise la matiere. Qui oserait pourtant soutenir qu'on ait alors repondu a la veritable question d'origine, qui se pose necessairement aux abords d'un systeme de cette importance? L'atomisme n'est pas une simple theorie de la matiere: c'est la plus large explication de la nature, la plus complete peut-etre et la plus vraisemblable qui ait jamais ete tentee. Il semble donc qu'on ne puisse se dispenser, avant d'en entreprendre l'examen suivant l'histoire, d'en indiquer, au moins d'un trait rapide, les racines profondes dans la reflexion ou dans l'experience primitives. About the Publisher Forgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.com This book is a reproduction of an important historical work. Forgotten Books uses state-of-the-art technology to digitally reconstruct the work, preserving the original format whilst repairing imperfections present in the aged copy. In rare cases, an imperfection in the original, such as a blemish or missing page, may be replicated in our edition. We do, however, repair the vast majority of imperfections successfully; any imperfections that remain are intentionally left to preserve the state of such historical works.". (shrink)

Predictive medicine presents opportunities to consider later life under conditions of illness, such as dementia. This paper examines how family caregivers (N = 27) assess the opportunity of prediction and early diagnosis of dementia for oneself based on their particular experience. Furthermore, it compares their attitudes with laypersons’ attitudes (N = 43) towards genetic testing of APOE. By this, we elaborate how much personal experience impacts anticipation and affects, but also moral attitudes towards predictive medicine. Differences in our settings do (...) not allow for direct comparison, so our analysis focuses on multiple similarities in the assessments of predictive (non-genetic vs. genetic) testing. Groups’ reasoning showed also differences influenced mainly by personal experience. Family caregivers addressed more responsibility towards family and had more hopes into medical treatments. To cope with the disease, they expressed expectations to start with medicine and care decisions as early as possible. Laypersons, however, stressed self-determination more and expressed worries about the influence of the pharmaceutical industry by referring to unnecessary medication and, implicitly, the medicalization of aging. (shrink)

Moutoussis, K., A. Maier, S. Zeki and N. K. Logothetis: Seeing invisible motion: responses of area V5 neurons in the awake-behaving macaque. Soc. for Neurosci. Abstr. 390.11, 1.

Aldo Leopold’s land ethic calls for an extension of ethical consideration to nonhuman components of the complex system he called “the land.” Although the basis for this extension was holistic, interpretations of Leopold’s holism leave one baffled at how he could see his land ethic as an extension of a system which recognizes individual human rights. Leopold’s critics and exponents alike have focused on the holism expressed in his definition of right and wrong. Both regard it as (...) a working criterion of morality to be applied directly to conduct, act by act. Both are mistaken. Leopold was an indirect holist, not a direct one. That is, he applied his holistic definition of right and wrong not as a role for judging conduct directly, case by case, but as a principle for judging conduct only indirectly by judging the roles, tastes, predilections, practices, and attitudes which influence it. (shrink)

Using concepts from abstract algebra and type theory, I analyze the structural presuppositions of any holistic ethical theory. This study is motivated by such recent holistic theories in environmental ethics as Aldo Leopold’s land ethic, James E. Lovelock’s Gaia hypothesis, Arne Naess’ deep ecology, and various aesthetic ethics of the sublime. I also discuss the holistic and type theoretic assumptions of suchstandard ethical theories as hedonism, natural rights theory, utilitarianism, Rawls’ difference principle, and fascism. I argue that although there (...) are several common senses of part-whole in ethical theory, the central sense of holism in ethics is that of a theory that defines its key moral idea as an emergent group property grounded in the relational properties of its individual constituents. Hedonism and Kantianism do not count as holistic in this sense. Natural rights theory does in adegenerate way. Utilitarianism and various environmental ethics are paradigm examples. I point out as a general structural weakness of environmental holistic theories that their first-order grounding in nonmoral vocabulary seems to preclude an explanation of many moral intuitions about human ethics. (shrink)

Using concepts from abstract algebra and type theory, I analyze the structural presuppositions of any holistic ethical theory. This study is motivated by such recent holistic theories in environmental ethics as Aldo Leopold’s land ethic, James E. Lovelock’s Gaia hypothesis, Arne Naess’ deep ecology, and various aesthetic ethics of the sublime. I also discuss the holistic and type theoretic assumptions of suchstandard ethical theories as hedonism, natural rights theory, utilitarianism, Rawls’ difference principle, and fascism. I argue that although there (...) are several common senses of part-whole in ethical theory, the central sense of holism in ethics is that of a theory that defines its key moral idea as an emergent group property grounded in the relational properties of its individual constituents. Hedonism and Kantianism do not count as holistic in this sense. Natural rights theory does in adegenerate way. Utilitarianism and various environmental ethics are paradigm examples. I point out as a general structural weakness of environmental holistic theories that their first-order grounding in nonmoral vocabulary seems to preclude an explanation of many moral intuitions about human ethics. (shrink)

Both individually and as a collection, these essays will promote understanding and provoke further debate amongst students and established scholars alike.

Rev. ed. of v. 1 of the author's Schicksalsanalyse, first published in 1944.

Keine ausführliche Beschreibung für "Reform der Wissenschaften, zur Herstellung der Einheit zwischen Theorie und Praxis, Teil 1" verfügbar.

This work has been selected by scholars as being culturally important, and is part of the knowledge base of civilization as we know it. This work was reproduced from the original artifact, and remains as true to the original work as possible. Therefore, you will see the original copyright references, library stamps (as most of these works have been housed in our most important libraries around the world), and other notations in the work. This work is in the public domain (...) in the United States of America, and possibly other nations. Within the United States, you may freely copy and distribute this work, as no entity (individual or corporate) has a copyright on the body of the work. As a reproduction of a historical artifact, this work may contain missing or blurred pages, poor pictures, errant marks, etc. Scholars believe, and we concur, that this work is important enough to be preserved, reproduced, and made generally available to the public. We appreciate your support of the preservation process, and thank you for being an important part of keeping this knowledge alive and relevant. (shrink)

Consciousness and Qualia is a philosophical study of qualitative consciousness, characteristic examples of which are pains, experienced colors, sounds, etc.

Asif A. Ghazanfar,1,3,* Hjalmar K. Turesson,1,3 statistical pattern recognition [16, 17] and psychophys- Joost X. Maier,1 Ralph van Dinther,2 ics [13, 18–23] have suggested that formants are signif- Roy D. Patterson,2 and Nikos K. Logothetis1 icant contributors to these indexical cues. It is likely, 1Max Planck Institute for Biological Cybernetics then, that detecting formants could have provided 72076 Tuebingen ancestral primates with indexical cues necessary for Germany navigating the complex social interactions that are the 2Centre for the Neural Basis of (...) Hearing essence of primate societies. One important indexical Department of Physiology cue is body size. Formant cues related to body size University of Cambridge could be used by monkeys to determine the sex (in sex- CB2 3EG Cambridge ually dimorphic species), degree of potential threat (e.g., United Kingdom whether a competitor is larger or smaller), and/or age of an individual, as such cues do for human listeners [13, 18, 20, 21]. Summary Formants are the result of acoustic filtering by the supralaryngeal vocal tract—the nasal and oral cavities Vocal-tract resonances (or formants) are acoustic sigabove the vocal folds. During vocal production, pulses natures in the voice and are related to the shape and of air generated by the rapid movement of the vocal length of the vocal tract. Formants play an important folds produce an acoustic signal. The frequency of these role in human communication, helping us not only to pulses—the glottal-pulse rate—determines the fundadistinguish several different speech sounds [1], but mental frequency of the signal, which in turn is perceived also to extract important information related to the as pitch. As the signal passes through the supralaryngphysical characteristics of the speaker, so-called ineal vocal tract, it excites resonances, resulting in the dexical cues. How did formants come to play such an enhancement of particular frequency bands; these are important role in human vocal communication? One the formants.. (shrink)

En 1975, Michelle Perrot s’interrogeait : « Refuser à la femme sa nature criminelle, n’est-ce pas encore une façon de la nier? ». Cette citation, rappelée en introduction (p. 5) puis en conclusion (p. 323), illustre bien la voie adoptée par Adrien Dubois. Le propos de cet ouvrage, en effet, est moins la violence faite aux femmes que celle qu’elles exercent. Il s’inscrit donc dans un champ historiographique très neuf. Des publications récentes ont montré combien les premières études féministe...

Given the apparent nondisplaceability and noncancellability of the derogatory content of slurs, it may appear puzzling that non-derogatory uses of slurs exist. Moreover, these uses seem to be in general available only to in-group speakers, thereby exhibiting a peculiar kind of context-sensitivity. In this paper the author argues that to understand non-derogatory uses we should consider slurs in terms of the kind of social practice their uses instantiate. A suitable theory of social practices has been proposed by McMillan. In typical (...) uses the practice is one of bigotry and discrimination. Non-derogatory uses are only possible to the extent that they consitute acts of an alternative, non-derogatory practice. In the core cases it must be a subversive practice of satire or reappropriation. The social identity of speakers is not an ultimately decisive factor but it is an important constitutive condition: most non-derogatory practices of slur-use can only be performed by a member of the target group. (shrink)

During the second half of the eighteenth century, the most powerful literary work in Britain was nonfictional: philosophy, history, biography, and political controversy. Leo Damrosch argues that this tendency is no accident; at the beginning of the modern age, writers were consciously aware of the role of cultural fictions, and they sought to ground those fictions in a real world beyond the text. Their political conservatism (often neglected by modern scholars) was an extensively thought out response to a world in (...) which meaning was inseparable from consensus, and in which consensus was increasingly under attack. Damrosch finds strong affinities between writers who are usually described as antagonists. The first chapter places Hume and Johnson in dialogue, showing that their responses to the challenge of their age have deep similarities, and that their thinking points forward in significant ways to twentieth-century pragmatism. Subsequent chapters explore the interrelationship of the fictive and the "real" in a wide range of works by Boswell, Gibbon, White, Burke, and Godwin. In its combination of literary, philosophical, and cultural criticism, this book will appeal to scholars in many fields as well as to nonacademic readers interested in intellectual history. (shrink)