Chairs
Professor Brian Butterworth FBA, University College London, UK
Professor Sarah Benson-Amram, University of Wyoming, USA
Professor Brian Butterworth FBA, University College London, UK
Brian Butterworth is in the Institute of Cognitive Neuroscience at University College London, where he is currently working on the neuroscience and the genetics of mathematical abilities and disabilities. He led two European networks, Neuromath and Numbra, that promoted multidisciplinary research on mathematical cognition. At UCL, he created the first master’s degree in cognitive neuroscience, and founded, and was first chair of, the Centre for Educational Neuroscience. He holds professorial positions at National Chengchi University, Taiwan, and at Melbourne University, Australia. He was elected Fellow of the British Psychological Society in 1993, and Fellow of the British Academy in 2002.
His popular science book, The Mathematical Brain (1999) was a best seller. The Dyscalculia Screener (2003) revolutionized the identification of this specific learning disability. His latest book, co-edited with Denis Mareschal and Andrew Tolmie, Educational Neuroscience, was published by Wiley in 2013.
Professor Sarah Benson-Amram, University of Wyoming, USA
Sarah Benson-Amram is the Director of the Animal Behavior and Cognition Laboratory and an assistant professor in the Department of Zoology and Physiology and in the Program in Ecology at the University of Wyoming, USA. Sarah is interested in understanding the evolution of complex cognitive abilities in animals and in investigating what animals know about their social and ecological environments. Additionally, she inquires how animals use this knowledge and their ability to learn about their environments in adaptive ways. Sarah’s research has been published in top international journals, such as the Proceedings of the National Academy of Sciences and the Proceedings of the Royal Society: B. Articles about her work have appeared in many news publications, including: the New York Times, The New Scientist, the BBC, National Public Radio, and Nature News. Sarah earned her PhD from Michigan State University in the USA and conducted her postdoctoral research at the University of St. Andrews in Scotland, UK.
09:05-09:50
How does the brain code quantity?
Professor Charles Gallistel, Rutgers University, USA
Abstract
The representation of numerosity must be embedded in a system for representing both discrete and continuous quantities. The most basic question then is the coding question: how does the brain encode a quantity? Neuroscience has nothing to offer in the way of an answer. Computer science does. The code is probably not unary, which rules out analog codes, like rate codes, because it must support the implementation of addition and multiplication over many orders of magnitude. Also analog codes have reading noise; the build up of purely computational error makes dead reckoning impossible. The representation must be able to approximate a huge range of the computable numbers (negative, positive, |n|>> 1 and |n|<<1). Twos-complement fixed point with settable offset (bias) and slope (scale) and a 2-bit to 8-bit integer portion has much to recommend it: 1) it obeys Weber’s Law. 2) It is the most computationally efficient of the known codes (least amount of hardware and least energy use). 3) It is particularly advised for Archimedean computations like dead reckoning, where a great many additions of small quantities may produce a quantity orders of magnitude larger. 4) It converts subtraction to addition. 5) The bit flipping that is the key to this conversion has a natural chemical realisation. 6) Division and multiplication by 2 are particularly simple and known to be psychologically easy and fast. 7) It can produce an exact code for large integers. 8) It solves the exact equality problem.
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Professor Charles Gallistel, Rutgers University, USA
Professor Charles Gallistel, Rutgers University, USA
C.R. Gallistel is Professor of Psychology, Emeritus and formerly Co-Director of the Rutgers Center for Cognitive Science at Rutgers. He taught previously at the University of Pennsylvania (1966-1989) and UCLA (1989-2000). He received his BA from Stanford in 1963 and his PhD in Psychology from Yale University in 1966. His research currently focuses on the development of quantitative, highly automated behavioural tests for memory malfunction in genetically manipulated mice, with the long-term goal of using genetic methods to discover the molecular, cellular and systems’ mechanisms underlying the foundational mechanisms of cognition. Other research interests are spatio-temporal learning, the theory of associative learning, the theory of action, non-verbal arithmetic in humans and non-human animals, matching behaviour, the perception of probability and electrical self-stimulation of the brain in the rat. He is a member of the American Academy of Arts and Sciences and the National Academy of Sciences. He has written several influential books.
09:50-10:35
Numerical assessment in the wild: insights from social carnivores and other mammals
Professor Sarah Benson-Amram, University of Wyoming, USA
Abstract
Playback experiments have proven to be a useful tool to investigate the extent to which wild animals understand numerical concepts and the factors that play into their decisions to respond to different numbers of vocalising conspecifics. Professor Benson-Amram will review a series of playback experiments conducted with wild social carnivores and other mammals, including African lions, spotted hyenas, and chimpanzees, which demonstrate that these animals can assess the number of conspecifics calling and respond based on numerical advantage. Additionally, she will discuss the key role that individual discrimination and cross-modal recognition can play in the ability of animals to assess the number of conspecifics vocalising nearby. For example, a listener hearing three vocalisations would benefit from being able to assess whether the vocalisations were emitted by the same individual or three different ones, and whether the identity of the callers match individuals they have recently seen in the area. Because the costs and benefits associated with approaching conspecifics change depending on the callers’ age, sex, and relatedness, listeners will likely adjust the level of their behavioural response to playback experiments where the identity of the callers change even when the number of callers is held constant. The listener’s sex, age, social rank and social system will also help determine their behavioural response to varying number of competitors. Finally, Professor Benson-Amram will discuss the implications of these findings for understanding how carnivores and other animals may have evolved a concept of ‘one’.
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Professor Sarah Benson-Amram, University of Wyoming, USA
Professor Sarah Benson-Amram, University of Wyoming, USA
Sarah Benson-Amram is the Director of the Animal Behavior and Cognition Laboratory and an assistant professor in the Department of Zoology and Physiology and in the Program in Ecology at the University of Wyoming, USA. Sarah is interested in understanding the evolution of complex cognitive abilities in animals and in investigating what animals know about their social and ecological environments. Additionally, she inquires how animals use this knowledge and their ability to learn about their environments in adaptive ways. Sarah’s research has been published in top international journals, such as the Proceedings of the National Academy of Sciences and the Proceedings of the Royal Society: B. Articles about her work have appeared in many news publications, including: the New York Times, The New Scientist, the BBC, National Public Radio, and Nature News. Sarah earned her PhD from Michigan State University in the USA and conducted her postdoctoral research at the University of St. Andrews in Scotland, UK.
11:00-11:45
At the roots of numerical cognition: insights from the day-old domestic chick (Gallus gallus)
Dr Rosa Rugani, University of Padova, Italy
Abstract
The ability to represent number and to use numerical concepts, such as real numbers, logarithms, and square roots, is a prerogative of a subset of human beings who have received specific mathematical instruction. In the last few decades, however, it has been demonstrated that non-verbal numerical abilities (i.e., those calculations that can be solved in the absence of words) are widespread within the animal Kingdom. To investigate the ontogenetic origins of numerical knowledge Dr Rugani used the domestic chick (Gallus gallus) as animal model. Unlike previous studies on adult animals, this model can be tested very early in life, allowing a precise control of sensory experience.
Dr Rugani will discuss evidence revealing that day-old domestic chicks can: (i) discriminate between different numbers of artificial social companions (i.e., objects they were exposed to soon after hatching); (ii) solve rudimentary arithmetic calculations, such as 1+1+1 vs. 1+1; and (iii) use ordinal information, identifying a target element, (e.g., the 4th), in a series of identical elements, on the basis of its numerical position in the series.
These studies suggest that non-verbal numerical comprehension can be observed in animals in the absence of (or with very reduced) experience, indicating that numerical competences may not have emerged ‘de novo’ in our species together with language, but that they could be based on an evolutionary-ancient precursor system.
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Dr Rosa Rugani, University of Padova, Italy
Dr Rosa Rugani, University of Padova, Italy
Rosa Rugani is a fellow at the Department of General Psychology at the University of Padova. Her research focus is the biological basis of cognitive processes. She was visiting researcher at the Center for Avian Cognition of the Saskatchewan University in Canada and at the Center for Cognitive Neuroscience of the Duke University in Durham, North Carolina (USA).
Her research has been published in prestigious scientific journals and her work has attracted media attention internationally because of her notable and original contribution to the advancement of our knowledge on the biological basis and evolution of animal mathematical cognition.
11:45-12:30
The primacy of numerical information
Professor Elizabeth Brannon, University of Pennsylvania, USA
Abstract
The ability to use numbers is one of the most complex cognitive abilities that humans possess and is often held up as a defining feature of the human mind. Alongside the uniquely human symbolic system for representing number we possess an approximate number system (ANS) that is evolutionarily ancient and developmentally conservative. In this talk Professor Brannon will illustrate the signatures of the ANS with experimental data from human babies and nonhuman primates. She will describe behavioural and neurobiological data that demonstrates how the human and nonhuman primate mind privileges numerical information over other types of quantitative information. She will argue that this numerical privilege implicates the biological importance of number in our evolutionary history.
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Professor Elizabeth Brannon, University of Pennsylvania, USA
Professor Elizabeth Brannon, University of Pennsylvania, USA
Dr Elizabeth M. Brannon graduated Summa Cum Laude from The University of Pennsylvania, where she received her BA in Physical Anthropology in 1992. In 1994, she received a Masters degree in Anthropology from Columbia where she worked with Dr Marina Cords. In 2000, she completed a PhD in Psychology in the laboratory of Dr Herb Terrace. Dr Brannon was faculty at Duke University from 2000-2015 where she served as Director of Graduate Studies for the Cognitive Neuroscience Admitting Program and Head of the Developmental Training Area. She is now a Professor of Psychology at The University of Pennsylvania. Dr Brannon has received numerous academic awards and honours including the Young Investigator Award from The Society for Experimental Psychology, a CAREER award from the National Science Foundation, a Merck Scholar Award, and a James McDonnell Scholar Award. She served on the editorial board of Psychological Science, Cognition, and Infancy, served as associate editor for Developmental Science and is currently serving as an associate editor for Open Mind. Dr Brannon’s research is currently funded by The National Science Foundation and The National Institutes of Health. Dr Brannon teaches courses on cognitive development and comparative psychology and her research probes the developmental and evolutionary building blocks of human mathematical knowledge.
13:30-14:15
Numerical abilities in fish
Dr Christian Agrillo, University of Padova, Italy
Abstract
While there is a well established tradition of studying numerical abilities in mammals and birds, it is only in the last decade that some studies have proposed that teleost fish possess similar capacities. There is substantial evidence showing that fish integrate numerical information and continuous quantities (such as cumulative surface area or convex hull) when assessing which group of fish or objects is larger/smaller. Typically, their performance is more accurate when both pieces of information are simultaneously available, although different fish species were also shown to use pure numerical information when prevented from using continuous quantities. The ability to discriminate small numbers of social companions seems to be already displayed at birth while large number discrimination develops later as a consequence of maturation and experience. The similarities among species (i.e., Gambusia holbrooki, Poecilia reticulata, Danio rerio, Pterophyllum scalare and Xenotoca eiseni) appear greater than the differences, and in general, the numerical capacities of fish partially match those reported in mammals and birds, raising the intriguing idea that our non-symbolic numerical abilities are more ancient than previously thought and date back at least as far as the divergence between fish and land vertebrates. Dr Agrillo will summarise the current state of art in the literature, focusing on three main topics: the relation between discrete (numerical) and continuous quantities, the ontogeny of numerical abilities in fish and the comparison of numerical abilities of fish and other vertebrates.
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Dr Christian Agrillo, University of Padova, Italy
Dr Christian Agrillo, University of Padova, Italy
Christian Agrillo is assistant professor at the Department of General Psychology of University of Padova. He got his PhD in Psychological Science in 2008 studying numerical abilities in fish species. After his PhD, he enlarged his investigation testing other vertebrates (e.g, chimpanzees, macaques, capuchin monkeys, dogs and cats). He was visiting scientist at Psychology Department of Essex University (UK), Institute of Cognitive Neuroscience (University College of London, UK) and Language Research Center of Georgia State University (USA).
Currently he is on the editorial boards of Animal Cognition, Scientific Reports, Plos one and Frontiers in Psychology. He has published more than 55 peer-reviewed journal articles and his research has been often featured on television and in magazines, including National Geographic, BBC, CNN and New Scientist.
14:15-15:00
Neural correlates of the numerical abilities of anurans: neurons that count
Professor Gary Rose, University of Utah, USA
Abstract
Acoustic communication plays important roles in the reproductive behaviour of anurans (frogs and toads). The acoustic repertoire of most species consists of several call types, but some anurans gradually increase the complexity of their calls during aggressive interactions between males and when approached by females. Observations of natural behaviour, as well as experimental studies, have revealed the numerical abilities of anurans in their acoustic communication. In particular, anurans are able to discern the number of properly timed pulses (notes) in their calls. The temporal intervals between successive pulses provide information about species identity and call type. A neural correlate of this numerical ability is evident in the responses of neurons that show ‘tuning’ for mid to fast pulse rates. These ‘interval-counting’ neurons respond only after at least a threshold number of pulses have occurred with the correct timing. A single interpulse interval that is 2-3 times the optimal value can reset this interval-counting process. Whole-cell recordings of the membrane potentials of midbrain neurons, in vivo, have revealed that complex interplay between activity-dependent excitation and inhibition contributes to this counting process. Single pulses primarily elicit inhibition. As additional pulses are presented with optimal intervals, cells are progressively depolarised and spike after a threshold number of intervals have occurred. Similarly, pulses that are presented at long intervals (slow rates) elicit primarily inhibition. As interpulse intervals are shortened, however, depolarisation progressively increases. The mechanisms that underlie this apparent shift in the balance of excitation and inhibition during a pulse sequence are under investigation.
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Professor Gary Rose, University of Utah, USA
Professor Gary Rose, University of Utah, USA
Gary Rose is Professor in the Department of Biology at the University of Utah. He has a BA from University of California, San Diego and MS and PhD degrees from Cornell University. His group studies animal behaviour at both ‘proximate’ and ‘ultimate’ levels, using methodologies ranging from neurophysiological analysis of single neuron function to behavioural studies in the lab and field. This allows them to both generate testable hypotheses regarding neuronal control and study the evolution of behaviours. Specific research interests include: the neural basis of electro-sensory behaviours in weakly electric fish; acoustic communication in anurans; neural mechanisms of audition; behavioural and physiological determinants of sex and colouration in marine wrasses; and song learning in songbirds. Professor Rose is a member of the Society for Neuroscience, the Acoustical Society of America and the International Society for Neuroethology.
15:00-15:45
Counting insects
Professor Lars Chittka, Queen Mary University of London, UK
Abstract
When counting-like abilities were first described in the honeybee in the mid 1990s, many scholars were sceptical, but such capacities have since been confirmed in a number of paradigms and also in other insect species, though curiously not in a solitary bee species in a natural foraging task. Counter to the intuitive notion that counting is a cognitively advanced ability, neural network analyses indicate that they can be mediated by very small neural circuits, and we should therefore perhaps not be surprised that insects and other small brained animals such as some small fish exhibit such abilities. One outstanding question is how bees actually acquire numerical information. Recent work on the question of whether bees can see ‘at a glance’ indicates that bees must acquire spatial detail by sequential scanning rather than parallel processing. This is confirmed for a numerosity task in the bumblebee.
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Professor Lars Chittka, Queen Mary University of London, UK
Professor Lars Chittka, Queen Mary University of London, UK
Lars Chittka is distinguished for his work on the evolutionary ecology of sensory systems and cognition, using insect-flower interactions as a model. He developed perceptual models of bee colour vision, allowing the derivation of optimal receiver systems as well as a quantification of the evolutionary pressures shaping flower signals. Chittka also made fundamental contributions to the understanding of animal cognition and its fitness benefits in the economy of nature. He explored phenomena such as numerosity, speed-accuracy tradeoffs, false memories and social learning in bees. His discoveries have made a substantial impact on the understanding of animal intelligence and its neural-computational underpinnings.
16:00-16:45
Comparative cognition of space and number: the case of the mental number line
Professor Giorgio Vallortigara, University of Trento, Italy
Abstract
Evidence will be discussed about encoding of geometry and forming associations between space and numbers in non-human animals. A variety of vertebrate species are able to reorient in a rectangular environment in accord with its metrical and sense relations, i.e. using simple Euclidian geometry. There seems to be a primacy of geometric over non-geometric information and, possibly, innate encoding of the sense of direction. Moreover, the hippocampal formation plays a key role in geometry navigation in mammals, birds and fish. Although some invertebrate species show similar behaviours, it is unclear whether the underlying mechanisms are shared. A disposition to associate numerical magnitudes onto a left-to-right-oriented mental number line appears to exist independently of cultural factors, and can be observed in animals with very little numerical experience, such as three-day old chicks. This evidence supports a nativistic foundation of such orientation. Preliminary evidence suggests that the same is observed in human neonates and in zebrafish.
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Professor Giorgio Vallortigara, University of Trento, Italy
Professor Giorgio Vallortigara, University of Trento, Italy
Giorgio Vallortigara is Professor of Neuroscience and Director of the Animal Cognition and Neuroscience Laboratory at the Centre for Mind/Brain Sciences of the University of Trento, Italy.
His major research interest is the study of cognition in a comparative and evolutionary perspective, with particular reference to the mechanisms underlying the use of geometry in spatial navigation and the origins of number and object cognition in the animal brain. He also studied the evolution of the asymmetry of the brain. He discovered functional brain asymmetry in the so-called ‘lower’ vertebrate species (fish and amphibians).
Professor Vallortigara’s most recent work has focused on the study of brain and cognition in insects.
On all these topics he has contributed numerous articles to scientific journals and book chapters, and is the author with L.J. Rogers and R.J. Andrew of the monograph Divided Brains (Cambridge University Press, 2013).