13:00-13:25
Synaesthesia, multisensory integration and imagery: associated or independent processes to bridge the senses?
Professor Fiona Newell, Trinity College Dublin, Ireland
Abstract
Although cross-modal interactions in the brain are often assumed to mediate synaesthesia, relatively few investigations have attempted to elucidate the nature of these interactions. Synaesthesia can be driven by integrated, multisensory rather than unisensory inputs, which is consistent with growing evidence that multisensory interactions are the norm, both within the brain and on behaviour. Moreover, evidence for cross-modal, synaesthetic-like associations in non-synaesthetes as well as enhanced multisensory processes in synaesthetes suggests that synaesthesia may be scaffolded onto multisensory processes which are common to all. However, this line of research has primarily focussed on cross-modal interactions that lie outside of synaesthetic experiences and has yet to address whether synaesthesia is associated with differences in how related sensory information is processed. In particular, the phenomenology and prevalence of synaesthesia suggests that cross-modal interactions associated with synaesthesia may be discrete, and not cognitively penetrable. However, evidence that synaesthesia can also be triggered by a mental image of the inducing stimulus challenges the idea that synaesthesia relies on discrete processes. Mental imagery itself has also been shown to induce multisensory illusions, but its role in broader synaesthetic experiences is mainly unknown. This can largely be attributed to our relatively poor understanding of mental imagery in sensory domains beyond vision. Current investigations are aimed at exploring individual differences in the ability to imagine stimulation across other sensory domains. Such abilities may, in turn, be linked with specific types of synaesthesia thus providing further insight into the cross-modal mechanisms underpinning synaesthesia.
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Professor Fiona Newell, Trinity College Dublin, Ireland
Professor Fiona Newell, Trinity College Dublin, Ireland
Fiona Newell is Professor of Experimental Psychology at the School of Psychology and Institute of Neuroscience in Trinity College Dublin, Ireland. She is a graduate in Psychology from Trinity College Dublin and subsequently obtained her PhD from the University of Durham, UK. During her post-doctoral training she spent time in various academic institutions including the MRC Cognition and Brain Sciences Unit, Cambridge, UK, the Weizmann institute, Israel and the Max Plank Institute for Biological Cybernetics, Germany. She returned to Trinity College in 2000 to take up a lectureship position. Her research is widely disseminated across leading journals in her field and she has received a number of awards including a US Fulbright Scholarship in 2011 and Best Impact award from Science Foundation Ireland in 2017. Professor Newell’s research is focussed on the behavioural and cortical correlates of multisensory perception in humans. As part of this programme, she has a strong interest in understanding the perceptual basis of synaesthesia, particularly how synaesthesia compares to typical multisensory processes.
13:25-13:50
Synesthesia evoked through mild sensory deprivation
Assistant Professor David Brang, University of Michigan, USA
Abstract
The natural environment contains auditory and visual cues, conveying both redundant and unique information about multisensory objects and events. To facilitate the processing of this information, the brain integrates auditory and visual signals, leading to better detection and response. While these multisensory benefits can result from one sensory system influencing another (eg, the spatial position of a tone modulates neural activity in areas of visual cortex that process similar regions of space), tones presented in isolation do not typically evoke conscious visual experiences. In individuals with synesthesia, however, these multisensory interactions do lead to qualitatively different experiences such as tones evoking flashes of light. Why, if multisensory interactions are present in all individuals, do only synesthetes experience multisensory hallucinations? Models of synesthesia propose that this difference is due to either reduced inhibition or increased connectivity between associated modalities in synesthetes. Case reports suggest that non-synesthetes can experience these sensations through drug ingestion, raising the possibility that synesthesia exists as a latent feature in all individuals, manifesting only when the balance of activity across the senses has been altered. This talk with presents data from a series of studies showing that aspects of generic multisensory interactions present in all individuals operate at early sensory levels, and that perturbation of these networks can lead to auditory-visual hallucinations (synesthesia) in the general population, providing tentative links between these conventionally distinct processes.
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Assistant Professor David Brang, University of Michigan, USA
Assistant Professor David Brang, University of Michigan, USA
David Brang is an Assistant Professor of Psychology at the University of Michigan, where he directs the Multisensory Perception Lab. His research examines how information from one sensory system influences processing in other sensory systems, as well as how this information is integrated in the brain. Dr Brang is interested in questions such as: why do some people see yellow when they hear a sound, how do we adjust our body-image to fit the boundaries of objects we use like our cars, and how does knowing the identity of a speaker and what their voice sounds like help us hear them better at a party? His current research examines multisensory processes using a variety of techniques including intracranial electrocorticography (ECoG) recordings in patients with epilepsy or brain tumours, enabling direct neuronal recordings from humans.
14:35-15:00
Using mirror-sensory synaesthesia to examine how we perceive and understand others
Professor Michael Banissy, Goldsmiths, University of London, UK
Abstract
Our capacity to share the experiences of others is a critical part of human behaviour. One process thought to be important for this is vicarious perception - the ability to co-represent the experiences of other people by matching the observed state onto representations of our own first-hand experience. For example, observing pain in other people activates some of the same network of brain regions as the first-hand experience of pain. The degree of vicarious perception is contextually and socially embedded. It has thus been used as a model system for exploring the broader mechanisms that underpin inter-personal representations and complex phenomena such as empathy. For most of us vicarious perception is implicit (i.e. unconscious), but for some individuals viewing another person’s state results in them literally experiencing a conscious sensation of the observed event (known as mirror-sensory synaesthesia). This talk will discuss what factors contribute to mirror-sensory synaesthesia and ways in which mirror-sensory synaesthesia can be used to enhance our knowledge of how we understand the experiences of others.
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Professor Michael Banissy, Goldsmiths, University of London, UK
Professor Michael Banissy, Goldsmiths, University of London, UK
Professor Michael Banissy is Head of Department of Psychology at Goldsmiths. He has contributed to several diverse research areas, with a specialism in Social Neuroscience. The breadth of his work is not only seen in scientific contributions, but also in his engagement to bring science to the public and industry. He is perhaps most well-known for his work on mirror-touch synaesthesia, where he is recognised as a leader in the field. He received the 2016 Spearman Medal and 2017 Bertelson Award (two of the highest accolades given to Psychologists) for this and related work (eg on empathy and social perception).
15:00-15:25
Neurophenomenological investigations of natural and trained synaesthesia
Professor Anil Seth, University of Sussex, UK
Abstract
Synaesthesia offers a unique window into the neurocognitive mechanisms underlying conscious perception. Intriguingly, recent evidence suggests that extensive perceptual and cognitive training can induce synesthesia-like experiences in non-synaesthetic adult volunteers (Bor et al, Scientific Reports, 2014, 4:7089). On the other hand, neuroimaging findings of colour-selective responses during natural (grapheme-colour) synaesthesia have been inconsistently reported. Focusing on grapheme-colour synaesthesia, I will describe a series of studies linking neural responses to phenomenology in both natural and ‘trained’ synaesthesia. For natural synaesthetes, our results show that colour-specific specific brain responses can be predicted by individual differences in synaesthetic phenomenology captured by ‘localisation’ and ‘automaticity’. For trained non-synaesthetes, we find coordinated phenomenological, behavioural and neurophysiological changes following a battery of adaptive cognitive training, revealing an unexpectedly powerful capability for perceptual plasticity even in adults. Finally, I will highlight an overlooked property of synaesthesia, which is that synaesthetic concurrents usually lack perceptual ‘presence’; that is, they are not experienced as being part of the external world. A theory based on counterfactual predictive processing suggests why this might be so.
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Professor Anil Seth, University of Sussex, UK
Professor Anil Seth, University of Sussex, UK
Anil Seth is Professor of Cognitive and Computational Neuroscience at the University of Sussex and Founding Co-Director of the Sackler Centre for Consciousness Science. He is also a Wellcome Trust Engagement Fellow and a Senior Fellow of the Canadian Institute for Advanced Research. In his work, Professor Seth seeks to understand the biological basis of consciousness by bringing together research across neuroscience, mathematics, artificial intelligence, computer science, psychology, philosophy and psychiatry. He holds degrees in Natural Sciences (MA, Cambridge, 1994), Knowledge-Based Systems (MSc, Sussex, 1996) and Computer Science and Artificial Intelligence (DPhil, Sussex, 2000).
15:50-17:00
Synthesis discussion
Professor Simon E Fisher, Max Planck Institute for Psycholinguistics, The Netherlands
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Professor Simon E Fisher, Max Planck Institute for Psycholinguistics, The Netherlands
Professor Simon E Fisher, Max Planck Institute for Psycholinguistics, The Netherlands
Professor Simon E Fisher is director of the Max Planck Institute for Psycholinguistics and Professor of Language and Genetics at the Donders Institute for Brain, Cognition & Behaviour in the Netherlands. Professor Fisher obtained his Natural Sciences degree from Cambridge University, and his Human Genetics DPhil from Oxford University. From 1996-2002, as a postdoctoral researcher at Oxford's Wellcome Trust Centre for Human Genetics, he carried out genomic investigations of human neurodevelopment, and was co-discoverer of FOXP2, the first gene implicated in a speech and language disorder. From 2002-2010, Professor Fisher was a Royal Society Research Fellow leading his own research group at the Wellcome Trust Centre. In 2010 he became head of the newly established Language and Genetics Department at the Max Planck Institute in Nijmegen. His research investigates unusual human traits by integrating data from genomics, psychology, neuroscience, developmental biology and evolutionary anthropology. Awards include the Francis Crick Medal and Lecture, and the Eric Kandel Young Neuroscientists Prize.