Our visual system can process information at both conscious and unconscious levels. Understanding the factors that control whether a stimulus reaches our awareness, and the fate of those stimuli that remain at an unconscious level, are the major challenges of brain science in the new millennium. Since its publication in 1984, Visual Masking has established itself as a classic text in the field of cognitive psychology. In the years since, there have been considerable advances in the cognitive neurosciences, and a (...) growth of interest in the topic of consciousness, and the time is ripe for a new edition of this text. Where most current approaches to the study of visual consciousness adopt a 'steady-state' view, the approach presented in this book explores its dynamic properties. This new edition uses the technique of visual masking to explore temporal aspects of conscious and unconscious processes down to a resolution in the millisecond range. The 'time slices' through conscious and unconscious vision revealed by the visual masking technique can shed light on both normal and abnormal operations in the brain. The main focus of this book is on the microgenesis of visual form and pattern perception - microgenesis referring to the processes occurring in the visual system from the time of stimulus presentation on the retinae to the time, a few hundred milliseconds later, of its registration at conscious or unconscious perceptual and behavioural levels. The book takes a highly integrative approach by presenting microgenesis within a broad context encompassing visuo-temporal phenomena, attention, and consciousness. (shrink)

We examined the updating of decisions made during visuo-motor processing when two sequentially presented stimuli, Prime1 and Prime2, primed discriminative responses to a following probe. In Experiment 1, the visibility of the two primes was suppressed or left intact by varying the stimulus onset asynchrony of the stimuli immediately following them. In Experiment 2, the visibility of Prime2 was suppressed or left intact by varying its spatial separation from the following probe. We found that Prime2 dominated the effects of Prime1; (...) that Prime2’s updating was stronger when the Prime2–probe SOA was 200 as compared to 53 ms; and that Prime2’s updating was weaker when the Prime2–probe spatial separation was 58 as compared to 0 minarc. We conclude that these effects are due to an interaction of spatial attention and the state of processing of Prime2. (shrink)

This new edition uses the technique of visual masking to explore temporal aspects of conscious and unconscious processes down to a resolution in the...

Using a metacontrast masking paradigm, prior studies have shown that a target’s color information and form information, can be processed without awareness and that unconscious color processing occurs at early, wavelength-dependent levels in the cortical information processing hierarchy. Here we used a combination of paracontrast and metacontrast masking techniques to explore unconscious color and form priming effects produced by blue, green, and neutral stimuli. We found that color priming in normal observers is significantly reduced when an additional paracontrast mask precedes (...) the target at optimal masking SOAs. However, no reduction of form-priming effects was obtained at similar optimal paracontrast SOAs. We conclude that unconscious color priming depends on an early, wavelength- or stimulus-dependent response of color neurons located at early cortical levels whereas unconscious form priming occurs at later levels. (shrink)

Visual stimuli as well as transcranial magnetic stimulation can be used: to suppress the visibility of a target and to recover the visibility of a target that has been suppressed by another mask. Both types of stimulation thus provide useful methods for studying the microgenesis of object perception. We first review evidence of similarities between the processes by which a TMS mask and a visual mask can either suppress the visibility of targets or recover such suppressed visibility. However, we then (...) also point out a significant difference that has important implications for the study of the time course of unconscious and conscious visual information processing and for theoretical accounts of the processes involved. We present evidence and arguments showing: that visual masking techniques, by revealing more detailed aspects of target masking and target recovery, support a theoretical approach to visual masking and visual perception that must take into account activities in two separate neural channels or processing streams and, as a corollary, that at the current stage of methodological sophistication visual masks, by acting in more highly specifiable ways on these pathways, provide information about the microgenesis of form perception not available with TMS masks. (shrink)

Susan Pockett presents sound arguments supporting her reinterpretations of data that Libet and co-workers used to support a number of intriguing and influential conclusions regarding the microgenesis and timing of conscious sensory experience and volitionally controlled motor responses. The following analysis, extending and elaborating some of her main arguments, proposes that Libet's experimental methodologies and rationales, and thus also his interpretation of data, are flawed and that neglect or ignorance of methodological and empirical constraints well known to sensory psychologists risks (...) drawing premature or faulty conclusions about the timing of conscious experience. (shrink)

Visual control of our actions can be unconscious as well as conscious. The book explores unconscious and conscious vision, investigated using psychophysical and brain-recording methods. The book sheds new light on and advances experimental, philosophical, and scholarly research on visual consciousness.

Experimental Phenomena of Consciousness is the definitive collection of consciousness phenomena in which awareness emerges as an experimental variable.

Empirical and theoretical foundations for the study of the temporal dynamics of mechanisms contributing to unconscious and conscious processing of visual information; from computational, psychological, neuropsychological, and neurophysiological perspectives.

A modified flanker task was used to assess the effects of spatial attention during conscious and nonconscious processing. In line with prior findings, we demonstrated that increasing spatial separation between flankers and probes diminished the differences between reaction times to the incongruent and congruent probe–flanker pairs. This trend occurred even when the identity of flankers was suppressed from awareness by a metacontrast mask, indicating that spatial attention can be allocated to information processed at the nonconscious, in addition to the conscious, (...) levels, that effects of spatial attention at these two levels can be equivalent, and that attention deployed at the nonconscious level of processing can be characterized by a spatial gradient that is nearly identical to that found at the conscious level of processing. (shrink)

Haluk Ogmen and Bruno G. Breitmeyer (eds.): The First Half Second: The Microgenesis and Temporal Dynamics of Unconscious and Conscious Visual Processes Content Type Journal Article Category Book Review Pages 61-65 DOI 10.1007/s11023-011-9266-7 Authors Ramesh Kumar Mishra, Centre of Behavioral and Cognitive Sciences, Allahabad University, Allahabad, India Journal Minds and Machines Online ISSN 1572-8641 Print ISSN 0924-6495 Journal Volume Volume 22 Journal Issue Volume 22, Number 1.

The emergence of modern sciences in the seventeenth century profoundly renewed our understanding of Nature. For the last three centuries new ideas of Nature have been continuously developed by theology, politics, economics, and science, especially the sciences of the material world. The situation is even more unstable today, now that we have entered an ecological mutation of unprecedented scale. Some call it the Anthropocene, but it is best described as a new climatic regime. And a new regime it certainly is, (...) since the many unexpected connections between human activity and the natural world oblige every one of us to reopen the earlier notions of Nature and redistribute what had been packed inside. So the question now arises: what will replace the old ways of looking at Nature? This book explores a potential candidate proposed by James Lovelock when he chose the name "Gaia" for the fragile, complex system through which living phenomena modify the Earth. The fact that he was immediately misunderstood proves simply that his readers have tried to fit this new notion into an older frame, transforming Gaia into a single organism, a kind of giant thermostat, some sort of New Age goddess, or even divine Providence. In this series of lectures on "natural religion", Bruno Latour argues that the complex and ambiguous figure of Gaia offers, on the contrary, an ideal way to disentangle the ethical, political, theological, and scientific aspects of the now obsolete notion of Nature. He lays the groundwork for a future collaboration among scientists, theologians, activists, and artists as they, and we, begin to adjust to the new climatic regime. (shrink)

L'origine dell'anima umana secondo Dante.--La dottrina d'Alberto Magno sull'Inchoatio formae.--Alberto Magno e san Tommaso.--La posizione di Alberto Magno di fronte all'averroismo.--L'anima umana secondo Sigieri.--Anima e corpo nel pensiero di san Tommaso.--L'aristotelismo della scolastica e i francescani.--Individualità e immortalità nell'averroismo e nel tomismo.

In Intuition et idéalités: Phénoménologie des objets mathématiques (2020), Dominique Pradelle questioned the nature of mathematical knowledge–the status of math.

Ontological pluralism is the view that there are different ways to exist. It is a position with deep roots in the history of philosophy, and in which there has been a recent resurgence of interest. In contemporary presentations, it is stated in terms of fundamental languages: as the view that such languages contain more than one quantifier. For example, one ranging over abstract objects, and another over concrete ones. A natural worry, however, is that the languages proposed by the pluralist (...) are mere notational variants of those proposed by the monist, in which case the debate between the two positions would not seem to be substantive. Jason Turner has given an ingenious response to this worry, in terms of a principle that he calls ‘logical realism’. This paper offers a counter-response on behalf of the ‘notationalist’. I argue that, properly applied, the principle of logical realism is no threat to the claim that the languages in question are notational variants. Indeed, there seems to be every reason to think that they are. (shrink)

... Le figure del terzo legislatore e del terzo giudice costituiscono la garanzia che la tutela dei deboli non renda debole né il dovere né il diritto, ma ne fortifichi la consapevolezza responsabile in ognuno di noi, mostrando il significato giuridico del ‘dono di senso’, nucleo, nella mia interpretazione dell’intenso magistero di Bruno Romano. (Dalla Presentazione di L. Avitabile).

Which entities should be accepted as part of the furniture of the world, and which not? What are pseudo-objects, if they are not properly objects? This collection explores the answers given to these questions by some key philosophers throughout the 20th century. It brings together essays by leading scholars on a subject of central importance to both metaphysics and the history of philosophy.".

This chapter challenges Cantor’s notion of the ‘power’, or ‘cardinality’, of an infinite set. According to Cantor, two infinite sets have the same cardinality if and only if there is a one-to-one correspondence between them. Cantor showed that there are infinite sets that do not have the same cardinality in this sense. Further, he took this result to show that there are infinite sets of different sizes. This has become the standard understanding of the result. The chapter challenges this, arguing (...) that we have no reason to think there are infinite sets of different sizes. It begins with an initial argument against Cantor’s claim that there are infinite sets of different sizes and then proceeds, by way of an analogy between Cantor’s mathematical result and Russell’s paradox, to a more direct argument. (shrink)

When reading contemporary theories of distributive justice, one could easily get the impression that questions of fiscal design are normatively speaking merely instrumental for realizing the distributive ideal. Once the overall conception of justice is settled upon, questions of how the state should arrange its institutions and policies are settled if they effectively and efficiently promote the preferred distribution. I argue that such pure instrumentalism is mistaken in the context of fiscal policy. As a result, there is nothing problematic or (...) morally arbitrary about accepting domain-specific principles of fiscal justice. (shrink)