R. Beau Lotto

R. Beau Lotto
Prof. University of London; Visiting Scholar NYU

PhD

About

85
Publications
31,234
Reads
How we measure 'reads'
A 'read' is counted each time someone views a publication summary (such as the title, abstract, and list of authors), clicks on a figure, or views or downloads the full-text. Learn more
2,308
Citations

Publications

Publications (85)
Article
Full-text available
Creative coding, or artistic creation through the medium of program instructions, is constantly gaining traction, and there is a steady stream of new resources emerging to support it. However, the question of how creative coding is carried out still deserves more attention. In what ways may the act of program development be rendered conducive to ar...
Article
Full-text available
Artists and scientists have long had an interest in the relationship between music and visual art, leading up to the present-day artform of correlated animation and music, “visual music.” Current live performance tools and paradigms for visual music however are subject to several limitations. The work detailed addresses these through a transdiscipl...
Article
Humans show a natural tendency to discount bad news while incorporating good news into beliefs (the "good news-bad news effect"), an effect that may help explain seemingly irrational risk taking. Understanding how this bias develops with age is important because adolescents are prone to engage in risky behavior; thus, educating them about danger is...
Data
Questions, answers and distracters used in the symbolic mathematics test. Participants were presented with up to 25 mathematics questions (5 per each of 5 levels) according to performance. Possible answers that the participant could chose from are presented in brackets, with the correct answer presented first. During the experiment the spatial pres...
Data
Zero-order and partial correlations. Pearson’s correlation coefficients (R) and corresponding significance levels (P) are shown for correlations between age, mathematics score, general education level (Ed), mathematics education level (MEd) and psychophysical task performance (with age and Weber fractions/thresholds log transformed and converted in...
Article
Full-text available
Sensitivity to visual numerosity has previously been shown to predict human mathematical performance. However, it is not clear whether it is discrimination of numerosity per se that is predictive of mathematics, or whether the association is driven by more general task demands. To test this notion we had over 300 participants (ranging in age from 6...
Conference Paper
Full-text available
The emergence of any organism's brain and behaviour cannot be explained solely by examining the organism itself. We must look beyond the organism and model the ecology as well. This is the philosophical difference between the approach that we propose and the traditional approaches that seek to model behaviour and/or neural networks. We propose trea...
Article
Students of Blackawton Primary School, Blackawton, Devon, the UK, conducted experiments to find out if bees can solve puzzles. The tests were conducted in the bee arena, a Plexiglas box that is 1 m high, 1 m wide, and 1 m deep. After training the bees in the arena, the students tested them three times to see if they learned anything during training...
Article
Understanding perception of colour is challenging because what we see is not always what is there, which is a phenomenon we call illusions. Here we review the nature of colour vision, and the problems facing most current models and explanations. Focusing on our recent research on humans, bees and computers, we describe a new, more ecologically base...
Article
Full-text available
This article considers visual perception, the nature of the information on which perceptions seem to be based, and the implications of a wholly empirical concept of perception and sensory processing for vision science. Evidence from studies of lightness, brightness, color, form, and motion all indicate that, because the visual system cannot access...
Article
Full-text available
Background: Real science has the potential to not only amaze, but also transform the way one thinks of the world and oneself. This is because the process of science is little different from the deeply resonant, natural processes of play. Play enables humans (and other mammals) to discover (and create) relationships and patterns. When one adds rule...
Article
Binocular rivalry occurs when a stimulus (e.g., horizontal bars) that is clearly visible, when presented to one eye, is periodically rendered invisible when a different stimulus is simultaneously presented to the other eye (vertical bars, for example). While the physiological basis of rivalry (and fusion) has been much debated, two general theories...
Article
Surface perception is fundamental to human vision, yet most studies of visual cortex have focused on the processing of borders. We therefore investigated the responses of human visual cortex to parametric changes in the luminance of uniform surfaces using functional MRI. Early visual areas V1 and V2/V3 showed strong and reliable increases in signal...
Article
Human perception of colour remains enigmatic largely because we frequently see the world ‘incorrectly’ — in other words, because we see illusions. Indeed, illusions have long been a key tool for investigating how and why we see what we do. In this talk I will present our recent work on evolving synthetic colour visual systems, which provides direct...
Article
Full-text available
4 ICREA-IDIBAPS, Barcelona This paper reviews the concept of presence in immersive virtual envi-ronments, the sense of being there signalled by people acting and responding realistically to virtual situations and events. We argue that presence is a unique phenomenon that must be distinguished from the degree of engage-ment, involvement in the portr...
Conference Paper
In this paper, the design and implementation of a visualised sound simulation environment is presented as an initial step to further laboratory experimentation. Preliminary laboratory experiments showed a positive learning curve in human auditory perception. Learning occurred when new information was processed with relevant existing knowledge in th...
Article
Determining the statistical relationships of images that facilitate robust visual behaviour is nontrivial. Here we ask if some spatial relationships are more easily learned by the visual brain than others. Visually naïve bumblebees were trained to recognise coloured artificial flowers in scenes of equal spatial complexity but differing patterns of...
Article
Full-text available
Background: The perception of brightness depends on spatial context: the same stimulus can appear light or dark depending on what surrounds it. A less well-known but equally important contextual phenomenon is that the colour of a stimulus can also alter its brightness. Specifically, stimuli that are more saturated (i.e. purer in colour) appear bri...
Article
Full-text available
Artists and scientists have a perpetual interest in the relationship between music and art. As technology has progressed, so too have the tools that allow the practical exploration of this relationship. Today, artists in many disparate fields occupy themselves with producing animated visual art that is correlated with music (called 'visual music')....
Conference Paper
Full-text available
In most contemporary forms of musical and other technologically mediated artistic performance, systems are used where digital control information is transmitted from the interfaces used by the performers, to the devices producing the intended output. There is considerable ongoing discussion regarding how this control data is mapped between its sour...
Conference Paper
Full-text available
Bio-inspired processes are involved more and more in today’s technologies, yet their modelling and implementation tend to be taken away from their original concept because of the limitations of the classical computation paradigm. To address this, systemic computation (SC), a model of interacting systems with natural characteristics, followed by a m...
Conference Paper
Full-text available
Previous work suggests that innate immunity and represen- tations of tissue can be useful when combined with artificial immune systems. Here we provide a new implementation of tissue for AIS us- ing systemic computation, a new model of computation and correspond- ing computer architecture based on a systemics world-view and supple- mented by the in...
Article
Understanding the percepts elicited by spectral distributions in visual stimuli (i.e. understanding the perception of colour) is made especially challenging by the peculiar phenomenology of colour contrast and constancy effects. Interestingly as the first systematic account of colour contrast was published in 1839 by the French chemist Michel Chevr...
Chapter
The quality of brightness – perhaps the simplest visual attribute we perceive – appears to be determined probabilistically. In this empirical conception of the perception of light, the stimulus-induced activity of visual cortical neurons does not encode the retinal image or the properties of the stimulus per se, but associations (percepts) determin...
Conference Paper
Full-text available
Reliability in computer or engineering systems is undoubt-edly a key requirement in the development process. Safety within critical control systems, and reliable data transfers, require tolerance to unexpected and unwanted phenom-ena. In biology, new cells can replace damaged cells [1], DNA is able to repair and replicate with error control [1]. Th...
Article
Full-text available
In contrast to the classical view of development as a preprogrammed and deterministic process, recent studies have demonstrated that stochastic perturbations of highly non-linear systems may underlie the emergence and stability of biological patterns. Herein, we address the question of whether noise contributes to the generation of the stereotypica...
Article
Full-text available
Here we describe a programme that will enable the performance of advanced real-time computer graphics by non-programmers through flexible modules that are easily exchanged and managed. Introduction From the colour organs of past centuries, to today's VJing and new media art performances, artists and scientists have shown perpetual interest in the l...
Article
Full-text available
Lightness illusions are fundamental to human perception, and yet why we see them is still the focus of much research. Here we address the question by modelling not human physiology or perception directly as is typically the case but our natural visual world and the need for robust behaviour. Artificial neural networks were trained to predict the re...
Chapter
Previous research on primarily the peripheral nervous system has shown that soluble growth factors help control key developmental events by contributing to dynamic autocrine and paracrine signalling systems. Much less is known about the roles of these substances in neocortical development. Using cell and tissue culture paradigms, we have demonstrat...
Data
Overfitting Caused by Training the ANN for Too Many Epochs The error on the training set continues to drop as the backpropagation algorithm continues, but the test error on novel “dead-leaves” images starts to rise after around 150–200 epochs. This overfitting is a problem with any nonparametric learning algorithm, such as ANNs, and a typical solut...
Data
The Effect of the Number of Hidden Nodes None of the test errors is significantly worse than the optimum, corresponding to four hidden nodes (two-tailed t-test; p > 0.05 in all cases). In each case, the number of training epochs was adjusted to minimise the test error. (31 KB DOC)
Data
The Effect of the Number of Training Records on ANNs with Four Hidden Nodes Providing more training examples leads to lower test errors, at a decreasing rate. (29 KB DOC)
Data
Various ANN Activation Functions Two-tailed t-tests show that: log sigmoid is not significantly different to tan sigmoid (p = 0.067); log sigmoid is significantly better than pure linear (p ≈ 0); tan sigmoid is significantly better than pure linear (p ≈ 0). (26 KB DOC)
Data
ANNs' Response to Various Stimuli during Training For each test stimulus, we selected two pixels that had identical reflectance values but generate illusory responses in humans. For the brightness contrast and White's stimuli, we used the pair of test mid-grey patches, and for the Hermann Grid we used an “intersection” pixel and an “edge” pixel hal...
Article
Full-text available
People who experience an immersive VR system usually report feeling as if they were really in the displayed virtual situation, and can often be observed behaving in accordance with that feeling, even though they know that they're not actually there. Researchers refer to this feeling as "presence" in virtual environments, yet the term has come to ha...
Article
Full-text available
The Presenccia project takes an operational approach to the concept of presence. Presenccia's approach lets the project team assess the extent of presence using tools beyond traditional questionnaires, and therefore avoid many of the problems involved with sole reliance on these. Instead, the team considers the extent to which mixed reality and VR...
Conference Paper
Full-text available
The constraint satisfaction problem (CSP) is one of the most prominent problems in artificial intelligence, logic, theoretical computer science, engineering and many other areas in science and industry. One instance of a CSP, the satisfiability problem in propositional logic (SAT), has become increasingly popular and has illuminated important insig...
Conference Paper
Full-text available
Computation in biology and in conventional computer architectures seem to share some features, yet many of their important characteristics are very different. To address this, (1) introduced systemic computation, a model of interacting systems with natural characteristics. Following this work, here we introduce the first platform implementing such...
Conference Paper
Full-text available
A system composed of multiple interacting components is capable of responding to contextual information and can produce a higher range of non-linear responses to stimuli compared to a modular system with a low degree of component interaction. However, the fitness landscape of highly integrated systems is more rugged indicating that such systems are...
Article
Much current vision research is predicated on the idea--and a rapidly growing body of evidence--that visual percepts are generated according to the empirical significance of light stimuli rather than their physical characteristics. As a result, an increasing number of investigators have asked how visual perception can be rationalized in these terms...
Conference Paper
Full-text available
This paper expands Mosaic World, an artificial life model, in order to directly test theories on the emergence of multicellular life. Five experiments are conducted and demonstrate that both the presence of predation and acciden- tal aggregation are sufficient conditions for the transition to multicellularity. In addition, it is shown that division...
Conference Paper
Full-text available
This paper investigates whether replacing non-modular artificial neural network brains of visual agents with modular brains improves their ability to solve difficult tasks, specifically, survive in a changing environment. A set of experiments was conducted and confirmed that agents with modular brains are in fact better. Further analysis of the evo...
Article
Bees, like humans, can continue to see a surface from its color even when the scene's global illuminant changes (which is a phenomenon called color constancy). It is not known, however, whether they can also generate color-constant behavior in more natural complex scenes that are lit by multiple lights simultaneously, conditions in which most compu...
Conference Paper
Full-text available
This paper investigates evolvability of artificial neural networks within an artificial life environment. Five different structural mutations are in- vestigated, including adaptive evolution, structure duplication, and incremental changes. The total evolvability indicator, Etotal, and the evolvability function through time, are calculated in each i...
Article
Full-text available
The principal challenge faced by any color vision system is to contend with the inherent ambiguity of stimulus information, which represents the interaction between multiple attributes of the world (e.g., object reflectance and illumination). How natural systems deal with this problem is not known, although traditional hypotheses are predicated on...
Conference Paper
Full-text available
The fundamental challenge faced by any visual system within natural environments is the ambiguity caused by the fact that light that falls on the system's sensors conflates multiple attributes of the physical world. Understanding the computational principles by which natural systems overcome this challenge and generate useful behaviour remains the...
Article
Recent findings show that colour processing, like most other sensory attributes, is shaped by experience. While such studies can reveal the mechanisms of development, can they also help uncover the mechanisms of perception?
Article
Full-text available
This report results from a contract tasking Institute of Ophthalmology as follows: The contractor will develop a series of models that will resolve visual ambiguity in progressively more complex situations. These will begin with the most simple reflectance of objects and at the end of the grant progress to correlated landscapes with competitive and...
Article
Surface perception is fundamental to human vision, yet most studies of visual cortex have focused on the processing of borders. We therefore investigated the responses of human visual cortex to parametric changes in the luminance of uniform surfaces by using functional MRI. Early visual areas V1 and V2/V3 showed strong and reliable increases in sig...
Article
We view the world with two eyes and yet are typically only aware of a single, coherent image. Arguably the simplest explanation for this is that the visual system unites the two monocular stimuli into a common stream that eventually leads to a single coherent sensation. However, this notion is inconsistent with the well-known phenomenon of rivalry;...
Article
Full-text available
The relationship between luminance (i.e., the photometric intensity of light) and its perception (i.e., sensations of lightness or brightness) has long been a puzzle. In addition to the mystery of why these perceptual qualities do not scale with luminance in any simple way, "illusions" such as simultaneous brightness contrast, Mach bands, Craik-O'B...
Article
There is evidence that developing thalamic cells become dependent for their survival on the integrity of their afferent and/or efferent connections, which may provide required levels of neural activity and/or essential neurotrophic factors. These connections develop in the second half of gestation in mice and, during this time (embryonic days 17-19...
Article
Rationalizing the perceptual effects of spectral stimuli has been a major challenge in vision science for at least the last 200 years. Here we review evidence that this otherwise puzzling body of phenomenology is generated by an empirical strategy of perception in which the color an observer sees is entirely determined by the probability distributi...
Article
The intention of this textbook is not to dismantle a current conception of vision and replace it with something entirely different. Since there is at present no consensus about the link between visual physiology and perception, there is nothing to dismantle, even if that was the aim. As it is, the intention is simply to build upon present knowledge...
Article
The colors perceived by humans in response to light stimuli are generally described in terms of four color categories (reds, greens, blues and yellows), the members of which are systematically arrayed around gray. This broadly accepted description of color sensation differs fundamentally from the light that induces it, which is neither 'circular' n...
Article
The perceived difference in brightness between elements of a patterned target is diminished when the target is embedded in a similar surround of higher luminance contrast (the Chubb illusion). Here we show that this puzzling effect can be explained by the degree to which imperfect transmittance is likely to have affected the light that reaches the...
Article
Full-text available
Many neurons die as the normal brain develops. How this is regulated and whether the mechanism involves neurotrophic molecules from target cells are unknown. We found that cultured neurons from a key forebrain structure, the dorsal thalamus, develop a need for survival factors including brain-derived neurotrophic factor (BDNF) from their major targ...
Article
Many otherwise puzzling aspects of the way we see brightness, colour, orientation and motion can be understood in wholly empirical terms. The evidence reviewed here leads to the conclusion that visual percepts are based on patterns of reflex neural activity shaped entirely by the past success (or failure) of visually guided behaviour in response to...
Article
The brightness of any luminant stimulus varies, often quite markedly, as a function of the context in which it is presented. An especially intriguing example of this phenomenon is the illusion described by Chubb and colleagues (1989) in which the apparent contrast of a patterned target is reduced when it is embedded in a pattern of the same spatial...
Article
For reasons not well understood, the color of a surface can appear quite different when placed in different chromatic surrounds. Here we explore the possibility that these color contrast effects are generated according to what the same or similar stimuli have turned out to signify in the past about the physical relationships between reflectance, il...
Article
Full-text available
Although it has long been apparent that observers tend to overestimate the magnitude of acute angles and underestimate obtuse ones, there is no consensus about why such distortions are seen. Geometrical modeling combined with psychophysical testing of human subjects indicates that these misperceptions are the result of an empirical strategy that re...
Article
Full-text available
Four different colors are needed to make maps that avoid adjacent countries of the same color. Because the retinal image is two dimensional, like a map, four dimensions of chromatic experience would also be needed to optimally distinguish regions returning spectrally different light to the eye. We therefore suggest that the organization of human co...
Article
The quality of brightness--perhaps the simplest visual attribute we perceive--appears to be determined probabilistically. In this empirical conception of the perception of light, the stimulus-induced activity of visual cortical neurons does not encode the retinal image or the properties of the stimulus per se, but associations (percepts) determined...
Article
Full-text available
Observation of human subjects shows that the spectral returns of equiluminant colored surrounds govern the apparent brightness of achromatic test targets. The influence of color on brightness provides further evidence that perceptions of luminance are generated according to the empirical frequency of the possible sources of visual stimuli, and sugg...
Article
Full-text available
A long-standing puzzle in vision is the assignment of illusory brightness values to visual territories based on the characteristics of their edges (the Craik-O'Brien-Cornsweet effect). Here we show that the perception of the equiluminant territories flanking the Cornsweet edge varies according to whether these regions are more likely to be similarl...
Article
Subplate neurons form a transient layer immediately below the embryonic cortex and die early in postnatal life. It has been suggested that trophic factors, perhaps coming from cortical afferents, maintain the initial survival of these cells. Later withdrawal of these factors may cause subplate cell death. We tested whether basic fibroblast growth f...
Article
The cerebral cortex is a multilayered tissue, with each layer differing in its cellular composition and connections. Axons from deep layer neurons project subcortically, many to the thalamus, whereas superficial layer neurons target other cortical areas. The mechanisms that regulate the development of this pattern of connections are not fully under...
Article
Mach bands, the illusory brightness maxima and minima perceived at the initiation and termination of luminance gradients, respectively, are generally considered a direct perceptual manifestation of lateral inhibitory interactions among retinal or other lower order visual neurons. Here we examine an alternative explanation, namely that Mach bands ar...
Article
If Mach bands arise as an empirical consequence of real-world luminance profiles, several predictions follow. First, the appearance of Mach bands should accord with the appearance of naturally occurring highlights and lowlights. Second, altering the slope of an ambiguous luminance gradient so that it corresponds more closely to gradients that are t...
Article
The mechanisms that determine whether developing CNS neurons live or die are poorly understood. We studied the role of the neurotrophins and fibroblast growth factors in the survival of embryonic thalamic neurons in culture. Dissociated embryonic dorsal thalamic neurons cultured at high density in defined serum-free medium survived and grew neurite...
Article
Full-text available
The afferent and efferent connections of the cerebral neocortex develop simultaneously toward the end of embryogenesis. At this stage, the neocortex comprises two main cell-dense layers: the thicker and more superficial cortical plate (future layers 2-6) and the thinner underlying subplate. Many early thalamocortical projections temporarily innerva...
Article
Cortical efferents grow from deep cortical layers to innervate numerous subcortical structures late in embryogenesis. The mechanisms that control their development are poorly understood. We co-cultured organotypic embryonic cortical explants with other tissues, maintaining a distance between them to avoid contact-mediated interactions. At embryonic...
Article
Recent in vitro experiments have provided useful insights into the development of connections between the thalamus and the cortex. While most of these previous studies focused on neurite guidance and target recognition, our experiments used a serum-free culture system to examine the possible roles of unidentified diffusible cortex-derived growth fa...
Article
The development of tonic activity and membrane excitability of MVN neurones was examined using extracellular and intracellular recordings in slices prepared from mice at various stages in the first post-natal month. The tonic spontaneous discharge rates of MVN cells as post-natal day 5 (P5) were typically below 5 imp/s, and gradually increased to r...
Article
Previous research on primarily the peripheral nervous system has shown that soluble growth factors help control key developmental events by contributing to dynamic autocrine and paracrine signalling systems. Much less is known about the roles of these substances in neocortical development. Using cell and tissue culture paradigms, we have demonstrat...
Article
The development of tonic activity and membrane excitability of MVN neurones was examined using extracellular and intracellular recordings in slices prepared from mice at various stages in the first post-natal month. The tonic spontaneous discharge rates of MVN cells as post-natal day 5 (P5) were typically below 5 imp/s, and gradually increased to r...