The segregation of image parts into foreground and background is an important aspect of the neural computation of 3D scene perception. To achieve such segregation, the brain needs information about border ownership; that is, the belongingness of a contour to a specific surface represented in the image. This article presents psychophysical data derived from 3D percepts of figure and ground that were generated by presenting 2D images composed of spatially disjoint shapes that pointed inward or outward relative to the continuous (...) boundaries that they induced along their collinear edges. The shapes in some images had the same contrast (black or white) with respect to the background gray. Other images included opposite contrasts along each induced continuous boundary. Psychophysical results demonstrate conditions under which figure-ground judgment probabilities in response to these ambiguous displays are determined by the orientation of contrasts only, not by their relative contrasts, despite the fact that many border ownership cells in cortical area V2 respond to a preferred relative contrast. Studies are also reviewed in which both polarity-specific and polarity-invariant properties obtain perceptual figure-ground grouping results. The FACADE and 3D LAMINART models are used to explain these data. Keywords: figure-ground separation, border ownership, perceptual grouping, surface filling-in, V2, V4, FACADE Theory. (shrink)

The principle of self-organization has acquired a fundamental significance in the newly emerging field of computational philosophy. Self-organizing systems have been described in various domains in science and philosophy including physics, neuroscience, biology and medicine, ecology, and sociology. While system architecture and their general purpose may depend on domain-specific concepts and definitions, there are (at least) seven key properties of self-organization clearly identified in brain systems: 1) modular connectivity, 2) unsupervised learning, 3) adaptive ability, 4) functional resiliency, 5) functional plasticity, (...) 6) from-local-to-global functional organization, and 7) dynamic system growth. These are defined here in the light of insight from neurobiology, cognitive neuroscience and Adaptive Resonance Theory (ART), and physics to show that self-organization achieves stability and functional plasticity while minimizing structural system complexity. A specific example informed by empirical research is discussed to illustrate how modularity, adaptive learning, and dynamic network growth enable stable yet plastic somatosensory representation for human grip force control. Implications for the design of “strong” artificial intelligence in robotics are brought forward. (shrink)

Consciousness is known to be limited in processing capacity and often described in terms of a unique processing stream across a single dimension: time. In this paper, we discuss a purely temporal pattern code, functionally decoupled from spatial signals, for conscious state generation in the brain. Arguments in favour of such a code include Dehaene et al.'s long-distance reverberation postulate, Ramachandran's remapping hypothesis, evidence for a temporal coherence index and coincidence detectors, and Grossberg's Adaptive Resonance Theory. A time-bin resonance model (...) is developed, where temporal signatures of conscious states are generated on the basis of signal reverberation across large distances in highly plastic neural circuits. The temporal signatures are delivered by neural activity patterns which, beyond a certain statistical threshold, activate, maintain, and terminate a conscious brain state like a bar code would activate, maintain, or inactivate the electronic locks of a safe. Such temporal resonance would reflect a higher level of neural processing, independent from sensorial or perceptual brain mechanisms. (shrink)

Two universal functional principles of Grossberg’s Adaptive Resonance Theory [19] decipher the brain code of all biological learning and adaptive intelligence. Low-level representations of multisensory stimuli in their immediate environmental context are formed on the basis of bottom-up activation and under the control of top-down matching rules that integrate high-level long-term traces of contextual configuration. These universal coding principles lead to the establishment of lasting brain signatures of perceptual experience in all living species, from aplysiae to primates. They are re-visited (...) in this concept paper here on the basis of examples drawn from the original code and from some of the most recent related empirical findings on contextual modulation in the brain, highlighting the potential of Grossberg’s pioneering insights and groundbreaking theoretical work for intelligent solutions in the domain of developmental and cognitive robotics. (shrink)

Region R Question: How many objects — entities, things — are contained in R? Ignore the empty space. Our question might better be put, 'How many material objects does R contain?' Let's stipulate that A, B and C are metaphysical atoms: absolutely simple entities with no parts whatsoever besides themselves. So you don't have to worry about counting a particle's top half and bottom half as different objects. Perhaps they are 'point-particles', with no length, width or breadth. Perhaps they are (...) extended in space without possessing spatial parts (if that is possible). Never mind. We stipulate that A, B and C are perfectly simple. We also stipulate that they are connected as follows. A and B are stuck together in such a way that when a force is applied to one of them, they move together 'as a unit'. Moreover, the two of them together exhibit behavior that neither would exhibit on its own — Perhaps they emit a certain sound, or glow in the dark — whereas C is.. (shrink)

While some are currently debating whether time may or may not be an illusion, others keep devoting their time to the science of consciousness. Time as such may be seen as a physical or a subjective variable, and the limitations in our capacity of perceiving and analyzing temporal order and change in physical events definitely constrain our understanding of consciousness which, in return, constrains our conceptual under-standing of time. Temporal codes generated in the brain have been considered as the key (...) to insight into neural function and, ultimately, as potential neural substrates of consciousness itself. On the basis of cur-rent evidence and opinion from neuroscience and philosophy, we consider the interrelation between con-sciousness and time in the light of Hegel and Heidegger’s concepts of Sein (Being) and Zeit (Time). We suggest that consciousness can be defined in terms of a succession of psychological moments where we realize that we exist in, and are part of, a present moment in time. This definition places all other percep-tual or sensorial processes which may characterize phenomenal experience at a different level of analysis and centers the debate around consciousness on the fundamental identity link between awareness of the Ich (I) and awareness of what Heidegger termed Ursprüngliche Zeit (original time). We argue that human consciousness has evolved from the ability to be aware of, to remember, and to predict temporal order and change in nature, and that the limits of this capacity are determined by limits in the functional plasticity of resonant brain mechanisms. Although the conscious state of the Self is the ultimate expression of this evolution, it is devoid of any adaptive function as such. (shrink)

Although symmetry has been discussed in terms of a major law of perceptual organization since the early conceptual efforts of the Gestalt school (Wertheimer, Metzger, Koffka and others), the first quantitative measurements testing for effects of symmetry on processes of Gestalt formation have seen the day only recently. In this study, a psychophysical rating study and a “foreground”-“background” choice response time experiment were run with human observers to test for effects of bilateral symmetry on the perceived strength of figure-ground in (...) triangular Kanizsa configurations. Displays with and without bilateral symmetry, identical physically-specified-to-total contour ratio, and constant local contrast intensity within and across conditions, but variable local contrast polarity and variable orientation in the plane, were presented in a random order to human observers. Configurations with bilateral symmetry produced significantly stronger figure-ground percepts reflected by greater subjective magnitudes and consistently higher percentages of “foreground” judgments accompanied by significantly shorter response times. These effects of symmetry depend neither on the orientation of the axis of symmetry, nor on the contrast polarity of the physical inducers. It is concluded that bilateral symmetry, irrespective of orientation, significantly contributes to the, largely sign-invariant, visual mechanisms of figure-ground segregation that determine the salience of figure-ground in perceptually ambiguous configurations. (shrink)

Analysis of grip force signals tailored to hand and finger movement evolution and changes in grip force control during task execution provide unprecedented functional insight into somatosensory cognition. Somatosensory cognition is a basis of our ability to manipulate, move, and transform objects of the physical world around us, to recognize them on the basis of touch alone, and to grasp them with the right amount of force for lifting and manipulating them. Recent technology has permitted the wireless monitoring of grip (...) force signals recorded from biosensors in the palm of the human hand to track and trace human grip forces deployed in cognitive tasks executed under conditions of variable sensory (visual, auditory) input. Non-invasive multi-finger grip force sensor technology can be exploited to explore functional interactions between somatosensory brain mechanisms and motor control, in particular during learning a cognitive task where the planning and strategic execution of hand movements is essential. Sensorial and cognitive processes underlying manual skills and/or hand-specific (dominant versus non-dominant hand) behaviors can be studied in a variety of contexts by probing selected measurement loci in the fingers and palm of the human hand. Thousands of sensor data recorded from multiple spatial locations can be approached statistically to breathe functional sense into the forces measured under specific task constraints. Grip force patterns in individual performance profiling may reveal the evolution of grip force control as a direct result of cognitive changes during task learning. Grip forces can be functionally mapped to from-global-to-local coding principles in brain networks governing somatosensory processes for motor control in cognitive tasks leading to a specific task expertise or skill. Under the light of a comprehensive overview of recent discoveries into the functional significance of human grip force variations, perspectives for future studies in cognition, in particular the cognitive control of strategic and task relevant hand movements in complex real-world precision task, are pointed out. (shrink)

Two universal functional principles of Grossberg’s Adaptive Resonance Theory decipher the brain code of all biological learning and adaptive intelligence. Low-level representations of multisensory stimuli in their immediate environmental context are formed on the basis of bottom-up activation and under the control of top-down matching rules that integrate high-level, long-term traces of contextual configuration. These universal coding principles lead to the establishment of lasting brain signatures of perceptual experience in all living species, from aplysiae to primates. They are re-visited in (...) this concept paper on the basis of examples drawn from the original code and from some of the most recent related empirical findings on contextual modulation in the brain, highlighting the potential of Grossberg’s pioneering insights and groundbreaking theoretical work for intelligent solutions in the domain of developmental and cognitive robotics. (shrink)

We show that true colors as defined by Chevreul (1839) produce unsuspected simultaneous brightness induction effects on their immediate grey backgrounds when these are placed on a darker (black) general background surrounding two spatially separated configurations. Assimilation and apparent contrast may occur in one and the same stimulus display. We examined the possible link between these effects and the perceived depth of the color patterns which induce them as a function of their luminance contrast. Patterns of square-shaped inducers of a (...) single color (red, green, blue, yellow, or grey) were placed on background fields of a lighter and a darker grey, presented on a darker screen. Inducers were always darker on one side of the display and brighter on the other in a given trial. The intensity of the grey backgrounds varied between trials only. This permitted generating four inducer luminance contrasts, presented in random order, for each color. Background fields were either spatially separated or consisted of a single grey field on the black screen. Experiments were run under three environmental conditions: dark-adaptation, daylight, and rod-saturation after exposure to bright light. In a first task, we measured probabilities of contrast, assimilation, and no effect in a three-alternative forced-choice procedure (background appears brighter on the ‘left’, on the ‘right’ or the ‘same’). Visual adaptation and inducer contrast had no significant influence on the induction effects produced by colored inducers. Achromatic inducers produced significantly stronger contrast effects after dark-adaptation, and significantly stronger assimilation in daylight conditions. Grouping two backgrounds into a single one was found to significantly decrease probabilities of apparent contrast. Under the same conditions, we measured probabilities of the inducers to be perceived as nearer to the observer inducers. These, as predicted by Chevreul’s law of contrast, were determined by the luminance contrast of the inducers only, with significantly higher probabilities of brighter inducers to be seen as nearer, and a marked asymmetry between effects produced by inducers of opposite sign. Implications of these findings for theories which attempt to link simultaneous induction effects to the relative depth of object surfaces in the visual field are discussed. (shrink)

Poorly saturated colors are closer to a pure grey than strongly saturated ones and, therefore, appear less “colorful”. Color saturation is effectively manipulated in the visual arts for balancing conflicting sensations and moods and for inducing the perception of relative distance in the pictorial plane. While perceptual science has proven quite clearly that the luminance contrast of any hue acts as a self-sufficient cue to relative depth in visual images, the role of color saturation in such figure-ground organization has remained (...) unclear. We presented configurations of colored inducers on grey ‘test’ backgrounds to human observers. Luminance and saturation of the inducers was uniform on each trial, but varied across trials. We ran two separate experimental tasks. In the relative background brightness task, perceptual judgments indicated whether the apparent brightness of the grey test background contrasted with, assimilated to, or appeared equal (no effect) to that of a comparison background with the same luminance contrast. Contrast polarity and its interaction with color saturation affected response proportions for contrast, assimilation and no effect. In the figure-ground task, perceptual judgments indicated whether the inducers appeared to lie in front of, behind, or in the same depth with the background. Strongly saturated inducers produced significantly larger proportions of foreground effects indicating that these inducers stand out as figure against the background. Weakly saturated inducers produced significantly larger proportions of background effects, indicating that these inducers are perceived as lying behind the backgrounds. We infer that color saturation modulates figure-ground organization, both directly by determining relative inducer depth, and indirectly, and in interaction with contrast polarity, by affecting apparent background brightness. The results point towards a hitherto undocumented functional role of color saturation in the genesis of form, and in particular figure-ground percepts in the absence of chromatostereopsis. (shrink)

Victor Vasarely's (1906–1997) important legacy to the study of human perception is brought to the forefront and discussed. A large part of his impressive work conveys the appearance of striking three-dimensional shapes and structures in a large-scale pictorial plane. Current perception science explains such effects by invoking brain mechanisms for the processing of monocular (2D) depth cues. Here in this study, we illustrate and explain local effects of 2D color and contrast cues on the perceptual organization in terms of figure-ground (...) assignments, i.e. which local surfaces are likely to be seen as “nearer” or “bigger” in the image plane. Paired configurations are embedded in a larger, structurally ambivalent pictorial context inspired by some of Vasarely's creations. The figure-ground effects these configurations produce reveal a significant correlation between perceptual solutions for “nearer” and “bigger” when other geometric depth cues are missing. In consistency with previous findings on similar, albeit simpler visual displays, a specific color may compete with luminance contrast to resolve the planar ambiguity of a complex pattern context at a critical point in the hierarchical resolution of figure-ground uncertainty. The potential role of color temperature in this process is brought forward here. Vasarely intuitively understood and successfully exploited the subtle context effects accounted for in this paper, well before empirical investigation had set out to study and explain them in terms of information processing by the visual brain. (shrink)

Detecting quality in large unstructured datasets requires capacities far beyond the limits of human perception and communicability and, as a result, there is an emerging trend towards increasingly complex analytic solutions in data science to cope with this problem. This new trend towards analytic complexity represents a severe challenge for the principle of parsimony (Occam’s razor) in science. This review article combines insight from various domains such as physics, computational science, data engineering, and cognitive science to review the specific properties (...) of big data. Problems for detecting data quality without losing the principle of parsimony are then highlighted on the basis of specific examples. Computational building block approaches for data clustering can help to deal with large unstructured datasets in minimized computation time, and meaning can be extracted rapidly from large sets of unstructured image or video data parsimoniously through relatively simple unsupervised machine learning algorithms. Why we still massively lack in expertise for exploiting big data wisely to extract relevant information for specific tasks, recognize patterns and generate new information, or simply store and further process large amounts of sensor data is then reviewed, and examples illustrating why we need subjective views and pragmatic methods to analyze big data contents are brought forward. The review concludes on how cultural differences between East and West are likely to affect the course of big data analytics, and the development of increasingly autonomous artificial intelligence (AI) aimed at coping with the big data deluge in the near future. Keywords: big data; non-dimensionality; applied data science; paradigm shift; artificial intelligence; principle of parsimony (Occam’s razor) . (shrink)

In the field theories in physics, any particular region of the presumed space-time continuum and all interactions between elementary objects therein can be objectively measured and/or accounted for mathematically. Since this does not apply to any of thefield theories, or any other neural theory, of consciousness, their explanatory power is limited. As discussed in detail herein, the matter is complicated further by the facts than any scientifically operational definition of consciousness is inevitably partial, and that the phenomenon has no spatial (...) dimensionality. Under the light of insights from research on meditation and expanded consciousness, chronic pain syndrome, healthy aging, and eudaimonic well being, we may conceive consciousness as a source of potential energy that has no clearly defined spatial dimensionality, but can produce significant changes in others and in the world, observable in terms of changes in time. It is argued that consciousness may have evolved to enable the human species to generate such changes in order to cope with unprecedented and/or unpredictable adversity. Such coping could, ultimately, include the conscious planning of our own extinction when survival on the planet is no longer an acceptable option. (shrink)

Colour information not only helps sustain the survival of animal species by guiding sexual selection and foraging behaviour but also is an important factor in the cultural and technological development of our own species. This is illustrated by examples from the visual arts and from state-of-the-art imaging technology, where the strategic use of colour has become a powerful tool for guiding the planning and execution of interventional procedures. The functional role of colour information in terms of its potential benefits to (...) behavioural success across the species is addressed in the introduction here to clarify why colour perception may have evolved to generate behavioural success. It is argued that evolutionary and environmental pressures influence not only colour trait production in the different species but also their ability to process and exploit colour information for goal-specific purposes. We then leap straight to the human primate with insight from current research on the facilitating role of colour cues on performance training with precision technology for image-guided surgical planning and intervention. It is shown that local colour cues in two-dimensional images generated by a surgical fisheye camera help individuals become more precise rapidly across a limited number of trial sets in simulator training for specific manual gestures with a tool. This facilitating effect of a local colour cue on performance evolution in a video-controlled simulator (pick-and-place) task can be explained in terms of colour-based figure-ground segregation facilitating attention to local image parts when more than two layers of subjective surface depth are present, as in all natural and surgical images. (shrink)

The laws and principles which predict how perceptual qualities can be extracted from the most elementary visual signals were discovered by the Gestalt psychologists(e.g., Wertheimer,1923; Metzger,1930, translated and re-editedbySpillmann in 2009 and2012, respectively). Their seminal work has inspired visual science ever since, andhas led to exciting discoveries which have confirmed the Gestalt idea that the human brain would have an astonishing capacity for selecting and combining critical visual signals to generate output representations for decision making and action. This capacity of (...) selection and integration enables the perception of form and space, and the correct estimation of relative positions, trajectories, and distances of objects represented in planar images. This paper addresses problems of perceptual organization with critical implications for visual interfaces, and the design of surgical simulator platforms in particular. (shrink)

Scientific studies have shown that non-conscious stimuli and représentations influence information processing during conscious experience. In the light of such evidence, questions about potential functional links between non-conscious brain representations and conscious experience arise. This article discusses models capable of explaining how statistical learning mechanisms in dedicated resonant circuits could generate specific temporal activity traces of non-conscious representations in the brain. How reentrant signaling, top-down matching, and statistical coincidence of such activity traces may lead to the progressive consolidation of neural (...) signatures of conscious experience in networks extending across large distances beyond functionally specialized brain regions is then explained. (shrink)

This selective review explores biologically inspired learning as a model for intelligent robot control and sensing technology on the basis of specific examples. Hebbian synaptic learning is discussed as a functionally relevant model for machine learning and intelligence, as explained on the basis of examples from the highly plastic biological neural networks of invertebrates and vertebrates. Its potential for adaptive learning and control without supervision, the generation of functional complexity, and control architectures based on self-organization is brought forward. Learning without (...) prior knowledge based on excitatory and inhibitory neural mechanisms accounts for the process through which survival-relevant or task-relevant representations are either reinforced or suppressed. The basic mechanisms of unsupervised biological learning drive synaptic plasticity and adaptation for behavioral success in living brains with different levels of complexity. The insights collected here point toward the Hebbian model as a choice solution for “intelligent” robotics and sensor systems. Keywords: Hebbian learning; synaptic plasticity; neural networks; self-organization; brain; reinforcement; sensory processing; robot control . (shrink)

Evolution and geometry generate complexity in similar ways. Evolution drives natural selection while geometry may capture the logic of this selection and express it visually, in terms of specific generic properties representing some kind of advantage. Geometry is ideally suited for expressing the logic of evolutionary selection for symmetry, which is found in the shape curves of vein systems and other natural objects such as leaves, cell membranes, or tunnel systems built by ants. The topology and geometry of symmetry is (...) controlled by numerical parameters, which act in analogy with a biological organism’s DNA. The introductory part of this paper reviews findings from experiments illustrating the critical role of two-dimensional (2D) design parameters, affine geometry and shape symmetry for visual or tactile shape sensation and perception-based decision making in populations of experts and non-experts. It will be shown that 2D fractal symmetry, referred to herein as the “symmetry of things in a thing”, results from principles very similar to those of affine projection. Results from experiments on aesthetic and visual preference judgments in response to 2D fractal trees with varying degrees of asymmetry are presented. In a first experiment (psychophysical scaling procedure), non-expert observers had to rate (on a scale from 0 to 10) the perceived beauty of a random series of 2D fractal trees with varying degrees of fractal symmetry. In a second experiment (two-alternative forced choice procedure), they had to express their preference for one of two shapes from the series. The shape pairs were presented successively in random order. Results show that the smallest possible fractal deviation from “symmetry of things in a thing” significantly reduces the perceived attractiveness of such shapes. The potential of future studies where different levels of complexity of fractal patterns are weighed against different degrees of symmetry is pointed out in the conclusion. (shrink)

The laws which predict how the perceptual quality of figure-ground can be extracted from the most elementary visual signals were discovered by the Gestaltists, and form an essential part of their movement (see especially Metzger, 1930, and Wertheimer, 1923 translated and re-edited by Lothar Spillmann, 2009 and 2012, respectively). Distinguishing figure from ground is a prerequisite for perception of both form and space (the relative positions, trajectories, and distances of objects in the visual field. The human brain has an astonishing (...) capacity for selecting and combining a few critical visual signals to accurately represent both form and space. (shrink)

Technological progress has brought about the emergence of machines that have the capacity to take human lives without human control. These represent an unprecedented threat to humankind. This paper starts from the example of chemical weapons, now banned worldwide by the Geneva protocol, to illustrate how technological development initially aimed at the benefit of humankind has, ultimately, produced what is now called the “Weaponization of Artificial Intelligence (AI)”. Autonomous Weapon Systems (AWS) fail the so-called discrimination principle, yet, the wider public (...) is largely unaware of this problem. Given that ongoing scientific research on AWS, performed in the military sector, is generally not made available to the public domain, many of the viewpoints on this subject, expressed across different media, invoke common sense rather than scientific evidence. Yet, the implications of a potential weaponization of our work as scientists, especially in the field of AI, are reaching further than some may think. The potential consequences of a deployment of AWS for citizen stakeholders are incommensurable, and it is time to raise awareness in the public domain of the kind of potential threats identified, and to encourage legal policies ensuring that these threats will not materialize. (shrink)

Can we identify potential long-term consequences of digitalisation on public health? Environmental studies, metabolic research, and state of the art research in neurobiology point towards the reduced amount of natural day and sunlight exposure of the developing child, as a consequence of increasingly long hours spent indoors online, as the single unifying source of a whole set of health risks identified worldwide, as is made clear in this review of currently available literature. Over exposure to digital environments, from abuse to (...) addiction, now concerns even the youngest (ages 0 to 2) and triggers, as argued on the basis of clear examples herein, a chain of interdependent negative and potentially long-term metabolic changes. This leads to a deregulation of the serotonin and dopamine neurotransmitter pathways in the developing brain, currently associated with online activity abuse and/or internet addiction, and akin to that found in severe substance abuse syndromes. A general functional working model is proposed under the light of evidence brought to the forefront in this review. (shrink)

The quantization error in a fixed-size Self-Organizing Map (SOM) with unsupervised winner-take-all learning has previously been used successfully to detect, in minimal computation time, highly meaningful changes across images in medical time series and in time series of satellite images. Here, the functional properties of the quantization error in SOM are explored further to show that the metric is capable of reliably discriminating between the finest differences in local contrast intensities and contrast signs. While this capability of the QE is (...) akin to functional characteristics of a specific class of retinal ganglion cells (the so-called Y-cells) in the visual systems of the primate and the cat, the sensitivity of the QE surpasses the capacity limits of human visual detection. Here, the quantization error in the SOM is found to reliably signal changes in contrast or colour when contrast information is removed from or added to the image, but not when the amount and relative weight of contrast information is constant and only the local spatial position of contrast elements in the pattern changes. While the RGB Mean reflects coarser changes in colour or contrast well enough, the SOM-QE is shown to outperform the RGB Mean in the detection of single-pixel changes in images with up to five million pixels. This could have important implications in the context of unsupervised image learning and computational building block approaches to large sets of image data (big data). (shrink)

According to one sort of epistemic relativist, normative epistemic claims (e.g., evidence E justifies hypothesis H) are never true or false simpliciter, but only relative to one or another epistemic system. In chapter 6 of Fear of Knowledge, Paul Boghossian objects to this view on the ground that its central notions cannot be explained, and that it cannot account for the normativity of epistemic discourse. This paper explores how the dogged relativist might respond.

Perceptual neuroscience has identified mechanisms of perceptual grouping which account for the ways in which visual sensitivity to ordered structure and regularities expresses itself, in behavior and in the brain. The need to actively construct order, notably representations of objects in depth, is mandated as soon as visual signals reach the retina, given the occlusion of retinal signals by retinal veins and other retinal elements or blur. Multiple stages of neural processing transform fragmented signals into visual key representations of 3D (...) scenes that can be used to control effective behaviors. Since our survival depends on our ability to pick up order in the physical world, and since we conceive the physical world as an ordered one, our perception must somehow be sensitive to order. The articles from this collection illustrate how texture dissimilarity, boundary completion, surface filling-in, and figure-ground segregation generate perceptual order. (shrink)

In psychophysical experiments, the use of a psychophysical procedure of brightness/darkness cancellation shed light on interactions between spatial arrangement and figure–ground contrast in the perceptual filling in of achromatic and colored surfaces.Achromatic and chromatic Kanizsa squares with varying contrast, contrast polarity, and inducer spacingwere used to test how these factors interact in the perceptual filling in of surface brightness or darkness. The results suggest that the neuronal processing of surfaces with apparent contrast, leading to figure–ground segregation (i.e., perceptual organization), is (...) governed by mechanisms that integrate both luminance contrast and spatial information carried by the inducing stimuli, while discarding information on contrast polarity or color. The findings are discussed in relation to earlier observations on brightness assimilation and contrast. They support theories of nonantagonistic neural mechanisms suppressing local contrast or color signs in brightnessbased figure–ground percepts. Such mechanismsmight be necessary to cancel potentially conflicting polarities in geometricallycomplex visual stimuli so that perceptual filling in resulting in the most plausible representation of figure and ground can be achieved. (shrink)

This bookreview discusses Piccolino and Wades' book on Galileo's impact on contemporary perception science.

Global society issues are putting increasing pressure on both small and large organizations to communicate ethically at all levels. Achieving this requires social skills beyond the choice of language or vocabulary and relies above all on individual social responsibility. Arguments from social contract philosophy and speech act theory lead to consider a communication contract that identifies the necessary individual skills for ethical communication on the basis of a limited number of explicit clauses. These latter are pragmatically binding for all partners (...) involved and help to ensure that the ground rules of cooperative communication are observed within a group or an organization. Beyond promoting ethical communication, the communication contract clarifies how individual discursive behaviour can be constructively and ethically monitored by group leaders in business meetings. A case study which shows what may happen when ground clauses of ethical communication are violated is presented. The conclusions of the study highlights why attempting to respect the communication contract is in the best interest of all partners at all levels within any group or organization. (shrink)

Symmetry in biological and physical systems is a product of self-organization driven by evolutionary processes, or mechanical systems under constraints. Symmetry-based feature extraction or representation by neural networks may unravel the most informative contents in large image databases. Despite significant achievements of artificial intelligence in recognition and classification of regular patterns, the problem of uncertainty remains a major challenge in ambiguous data. In this study, we present an artificial neural network that detects symmetry uncertainty states in human observers. To this (...) end, we exploit a neural network metric in the output of a biologically inspired Self- Organizing Map Quantization Error (SOM-QE). Shape pairs with perfect geometry mirror symmetry but a non-homogenous appearance, caused by local variations in hue, saturation, or lightness within and/or across the shapes in a given pair produce, as shown here, a longer choice response time (RT) for “yes” responses relative to symmetry. These data are consistently mirrored by the variations in the SOM-QE from unsupervised neural network analysis of the same stimulus images. The neural network metric is thus capable of detecting and scaling human symmetry uncertainty in response to patterns. Such capacity is tightly linked to the metric’s proven selectivity to local contrast and color variations in large and highly complex image data. (shrink)

The fundamental question about the origin of human persons asks for a multidisciplinary approach. Biology and genetics have made remarkable progress in the last two decades. In addition, (pre-) history, philosophy, and anthropology could contribute significantly to a correct solution. Also, the Jewish-Christian tradition could provide elements to the complex puzzle. The present study attempts to show that recent genetic data can be an integrated part of a coherent view of the origin of human persons.

Victims of oppression are often called to let go of their anger in order to facilitate better discussion to bring about the end of their oppression. According to Amia Srinivasan, this constitutes an affective injustice. In this paper, we use research on emotion regulation to shed light on the nature of affective injustice. By drawing on the literature on emotion regulation, we illustrate specifically what kind of work is put upon people who are experiencing affective injustice and why it is (...) damaging. We begin by explaining affective injustice and how it can amount to a call for emotion regulation. Then we explain the various techniques that can be used to regulate emotions and explain how each might be harmful here. In the penultimate section of the paper, we explain how the upshot of this is that victims of affective injustice are left with a dilemma. Either they try to regulate their anger in a way that involves ignoring the fact of their oppression or they regulate it in a way that is likely to be harmful for them. Finally, we consider whether there are any good solutions to this dilemma, and how this issue opens up the possibility for further research into emotion regulation and moral philosophy. (shrink)

Results from three experiments using spatial forced-choice techniques show that an illusory contour improves the detectability of a spatially superimposed, 1pixel-thin subthreshold line of either contrast polarity. Furthermore, the subthreshold line is found to enhance the visibility of an illusory contour bridging the gap between the two colinear edges of physically defined boundaries. Stimuli which do not induce illusory contours, but reduce uncertainty about the spatial position of the line, give rise to a slight detection facilitation, but the threshold of (...) 75% correct responses is not attained. The data indicate that superimposing illusory contours and 1pixel thin subthreshold lines produces interactions which are similar to classic subthreshold summation. This provides psychophysical evidence for the functional equivalence of illusory and real lines, as suggested by neurophysiological data from single-cell recordings in V1 and V2 of cats and primates. (shrink)

The perception of brightness differences in Ehrenstein figures and of illusory contours in phase-shifted line gratings was investigated as a function of the contrast polarity of the inducing elements. We presented either continuous lines or line-like arrangements composed of aligned dashes or dots whose spacing was varied. A yes/no procedure was used in which naive observers had to decide whether or not they perceived a brightness difference in a given Ehrenstein figure or an illusory contour in a phase-shifted line grating. (...) The results show that brightness differences are perceived to some extent in Ehrenstein figures with inducers of opposite polarity of contrast; however, the percentage of yes response was systematically lower and response times were longer than for figures with inducers of the same polarity. Phase-shifted line gratings with lines of opposite polarity of contrast yielded stronger illusory contours and shorter response times than those with lines of the same polarity. When the sign of contrast was not the same within a given line of induction, neither differences in brightness nor illusory contours were perceived. The results suggest that the mechanisms that lead to apparent differences in brightness are more sensitive to input of the same contrast polarity, the mechanisms generating illusory contours more sensitive to input of opposite polarity. The data are discussed in the light of a multistage approach to illusory form perception and some implications for cortical models of illusory contour integration are discussed. (shrink)

Is it appropriate to honor artists who have created great works but who have also acted immorally? In this article, after arguing that honoring involves identifying a person as someone we ought to admire, we present three moral reasons against honoring immoral artists. First, we argue that honoring can serve to condone their behavior, through the mediums of emotional prioritization and exemplar identification. Second, we argue that honoring immoral artists can generate undue epistemic credibility for the artists, which can lead (...) to an indirect form of testimonial injustice for the artists’ victims. Third, we argue, building on the first two reasons, that honoring immoral artists can also serve to silence their victims. We end by considering how we might respond to these reasons. (shrink)

Brincat and Westheimer [Journal of Neurophysiology 83 (2000) 1900] have reported facilitating interactions in the discrimination of spatially separated target orientations and co-linear inducing orientations by human observers. With smaller gaps between stimuli (short-range effects), facilitating interactions were found to depend on the contrast polarity of the stimuli. With larger gaps (longrange effects), only co-linearity of the stimuli seemed necessary to produce facilitation. In our study, the dependency of facilitating interactions on the intensity (luminance) of line stimuli is investigated by (...) measuring detection thresholds for a target line separated from the end of an inducing line by co-axial gaps ranging from 5 to 200 min of visual arc. We find facilitating interactions between target and inducing orientations, producing short-range and long-range effects similar to those reported by Brincat and Westheimer. In addition, detection thresholds as a function of the co-axial separation between target and inducing line reveal an interaction between the spatial regime of facilitating effects and the luminance of the stimuli. Short-range effects are found to be sensitive to changes in local intensity while long-range effects remain unaffected. (shrink)

The family poses problems for liberal understandings of social justice, because of the ways in which it bestows unearned privileges. This is particularly stark when we consider inter-generational inequality, or ‘class fate’ – the ways in which inequality is transmitted from one generation to the next, with the family unit ostensibly a key conduit. There is a recognized tension between the assumption that families should as far as possible be autonomous spheres of decision-making, and the assumption that we should as (...) far as possible equalize the life chances of all children, regardless of background. In this article I address this tension by way of recent liberal egalitarian literature, and consideration of the different dimensions of class fate. I argue, firstly, that the tension may not be of the a priori nature which liberals have tended to identify – and secondly, that as well as distributive and recognition-based aspects, the notion of contributive justice provides a particularly illuminating way of analyzing what is wrong about class fate, and the role of the family in promoting it. (shrink)

Planar geometry was exploited for the computation of symmetric visual curves in the image plane, with consistent variations in local parameters such as sagitta, chordlength, and the curves’ height-to-width ratio, an indicator of the visual area covered by the curve, also called aspect ratio. Image representations of single curves (no local image context) were presented to human observers to measure their visual sensation of curvature magnitude elicited by a given curve. Nonlinear regression analysis was performed on both the individual and (...) the average data using two types of model: (1) a power function where. (shrink)

In what way might public statues wrong people? In recent years, philosophers have drawn on speech act theory to answer this question by arguing that statues constitute harmful or disrespectful forms of speech. My aim in this paper will be add a different theoretical perspective to this discussion. I will argue that while the speech act approach provides a useful starting point for thinking about what is wrong with public statues, we can get a fuller understanding of these wrongs by (...) drawing on resources from recent work in situated affectivity. I will argue that public statues can be understood as affective artifacts and that this can both help us understand both the deep affective wrongs caused by public statues and offer a possible explanation as to why some people are so strongly opposed to their removal. (shrink)

The rise of Artificial Intelligence (AI) has produced prophets and prophecies announcing that the age of artificial consciousness is near. Not only does the mere idea that any machine could ever possess the full potential of human consciousness suggest that AI could replace the role of God in the future, it also puts into question the fundamental human right to freedom and dignity. This position paper takes the stand that, in the light of all we currently know about brain evolution (...) and the never-stopping formation of adaptive neural circuitry for learning, memory, decision making and, ultimately, fully conscious reasoning and creativity in the human species, the idea of an artificial consciousness appears misconceived. The paper highlights some of the major reasons why. While awareness to external stimuli for processes such as perception, recognition, and operational problem solving is under the direct control of functionally specific brain networks associated with sensory and cognitive functions across animal species, consciousness is a unique property of the human mind. (shrink)

What, if anything, is problematic about the involvement of celebrities in democratic politics? While a number of theorists have criticized celebrity involvement in politics (Meyer 2002; Mills 1957; Postman 1987) none so far have examined this issue using the tools of social epistemology, the study of the effects of social interactions, practices and institutions on knowledge and belief acquisition. This paper will draw on these resources to investigate the issue of celebrity involvement in politics, specifically as this involvement relates to (...) democratic theory and its implications for democratic practice. We will argue that an important and underexplored form of power, which we will call epistemic power, can explain one important way in which celebrity involvement in politics is problematic. This is because unchecked uses and unwarranted allocations of epistemic power, which celebrities tend to enjoy, threaten the legitimacy of existing democracies and raise important questions regarding core commitments of deliberative, epistemic, and plebiscitary models of democratic theory. We will finish by suggesting directions that democratic theorists could pursue when attempting to address some of these problems. (shrink)

How might people be wronged in relation to their feelings, moods, and emotions? Recently philosophers have begun to investigate the idea that these kinds of wrongs may constitute a distinctive form of injustice: affective injustice. In previous work, we have outlined a particular form of affective injustice that we called emotional imperialism. This paper has two main aims. First, we aim to provide an expanded account of the forms that emotional imperialism can take. We will do so by drawing inspiration (...) from William Reddy’s (2001) concept of an emotional regime and investigating ways in which colonial powers of the eighteenth to twentieth centuries sought to impose their emotional regimes on their colonial subjects. Second, we will offer more expansive accounts of both emotional imperialism and affective injustice that can accommodate these additional forms of emotional imperialism. (shrink)

How should we respond to historical figures who played an important role in their country’s history but have also perpetrated acts of great evil? Much of the existing philosophical literature on this topic has focused on explaining why it may be wrong to celebrate such figures. However, a common response that is made in popular discussions around these issues is that we should not judge historical figures by today’s standards. Our goal in this paper is to examine the most plausible (...) way to understand this objection. We will examine three different interpretations of this argument. First, we will examine a view we call Temporal Moral Relativism, according to which moral standards are relative to particular points in time. Next, we outline Blame Relativism, the view that people from the past may be excused from blame for acts of conventionalized wrongdoing. Finally, we outline Ideals Relativism, according to which our moral ideals are partially relative to the time in which we live. We argue that Ideals Relativism provides the most plausible interpretation of this argument. (shrink)

While moral philosophers have paid significant attention to the concept of moral supererogation, far less attention has been paid to the possibility that supererogation may also exist in other areas of normativity. Recently, though, philosophers have begun to consider the possible existence of prudential, epistemic, aesthetic and sporting supererogation. These discussions tend to focus on aspects of our practices in these areas of normativity that suggest an implicit acceptance of the existence of supererogation. In this chapter, I will offer a (...) different kind of defense of non-moral supererogation. I will begin by considering a particular kind of argument made in support of moral supererogation. According to this line of argument, we should accept the existence of moral supererogation because a moral code which makes room for supererogation is likely to be more effective at promoting morally desirable behavior than a moral code which leaves no room for the supererogatory. I will begin by outlining this argument. I will then develop a similar line of argument for prudential, epistemic, aesthetic, and sporting norms. (shrink)

In this manuscript, published here for the first time, Tarski explores the concept of logical notion. He draws on Klein's Erlanger Programm to locate the logical notions of ordinary geometry as those invariant under all transformations of space. Generalizing, he explicates the concept of logical notion of an arbitrary discipline.

The testimonies of celebrities affect the lives of their many followers who pay attention to what they say. This gives celebrities a high degree of epistemic power, which has come under close scrutiny during the COVID-19 pandemic. This paper investigates the duties that arise from this power. We argue that celebrities have a negative duty of testimonial justice not to undermine trust in authoritative sources by spreading misinformation or directing attention to untrustworthy sources. Moreover, celebrities have a general imperfect duty (...) to try to correct for an unjust distribution of attention by redirecting it to those who deserve it. During a pandemic this may become a perfect one, due to the harm that could be prevented if people follow the advice of experts. Relatedly, we argue that celebrities have an imperfect duty to promote behavior that will reduce the spread of a pandemic. We outline three ways they might do so: they might take on the position of a role model, they may act as a salience magnet or they can direct people’s attention towards others who have taken on these roles. (shrink)

With his bestselling publication, A Brief History of Time, Stephen Hawking introduced in 1988 a new genre by connecting modern science with the question of the existence of God. In the posthumous publication Brief Answers to the Big Questions, he continues with his quest for the ultimate truth. The current study presents a philosophical analysis of this search in terms of the classical philosophy of Aristotle and Aquinas. Causality is the central concept employed by Hawking. However, its meaning, in the (...) modern scientific and philosophical literature, is limited to temporal causality in contrast to the view of classical philosophy. Only the latter one accepts causality from outside space and time, with other words, a reality transcending the material world. In a quote presented in the discussion, Hawking defines himself as an atheist. After a careful reading of his writings, however, doubts arise about his unbelief. (shrink)

In this chapter we analyse the nature and ethical implications of parasocial relationships. While this type of relationship has received significant attention in other interdisciplinary fields such as celebrity studies and fan studies, philosophers have so far had very little to say about them. Parasocial relationships are usually defined as asymmetrical, in which a media-user closely relates to a media-personality as if they were a friend or family member, and where this connection is mostly unreciprocated. We focus on the most (...) typical form of this kind of relationship, between fans and celebrities. We argue that a parasocial relationship between fan and celebrity is a distinct kind of personal relationship, constituted by three basic structural asymmetries: attention, communication, and epistemic. These asymmetries give rise to a more substantial asymmetry concerning the way in which celebrities and fans have ‘directive’ or ‘interpretative’ influence over each other’s identity. This can lead to a failure of recognition respect, and generates ethical responsibilities for both fans and celebrities. We conclude by noting that the structural asymmetries we find in parasocial relationships are present in many other types of relationship, especially those in which one person holds a position of power. As such, it is valuable to pay attention to the way in which asymmetries point to forms of parasociality in these other relationships, and the extent to which they give rise to distinct ethical responsibilities. (shrink)

It has become increasingly popular for sports fans, pundits, coaches and players to appeal to ideas of ‘sporting integrity’ when voicing their approval or disapproval of some aspect of the sporting world. My goal in this paper will be to examine whether there is any way to understand this idea in a way that both makes sense of the way in which it is used and presents a distinctly ‘sporting’ form of integrity. I will look at three recent high-profile sporting (...) incidents that caused sporting integrity to be called into question. I will then examine three different ways in which philosophers have sought to understand integrity and examine whether any of these accounts can provide us with a plausible account of sporting integrity. I will argue that such an account can be given and show how this helps us to understand the three cases. (shrink)

Following the pioneering studies of the receptive field (RF), the concept gained further significance for visual perception by the discovery of input effects from beyond the classical RF. These studies demonstrated that neuronal responses could be modulated by stimuli outside their RFs, consistent with the perception of induced brightness, color, orientation, and motion. Lesion scotomata are similarly modulated perceptually from the surround by RFs that have migrated from the interior to the outer edge of the scotoma and in this way (...) provide filling-in of the void. Large RFs are advantageous to this task. In higher visual areas, such as the middle temporal and inferotemporal lobe, RFs increase in size and lose most of their retinotopic organization while encoding increasingly complex features. Whereas lowerlevel RFs mediate perceptual filling-in, contour integration, and figure–ground segregation, RFs at higher levels serve the perception of grouping by common fate, biological motion, and other biologically relevant stimuli, such as faces. Studies in alert monkeys while freely viewing natural scenes showed that classical and nonclassical RFs cooperate in forming representations of the visual world. Today, our understanding of the mechanisms underlying the RF is undergoing a quantum leap. What had started out as a hierarchical feedforward concept for simple stimuli, such as spots, lines, and bars, now refers to mechanisms involving ascending, descending, and lateral signal flow. By extension of the bottom-up paradigm, RFs are nowadays understood as adaptive processors, enabling the predictive coding of complex scenes. Top-down effects guiding attention and tuned to task-relevant information complement the bottom-up analysis. (shrink)