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Reeder RR, Sala G, van Leeuwen TM. A novel model of divergent predictive perception. Neurosci Conscious 2024; 2024:niae006. [PMID: 38348335 PMCID: PMC10860603 DOI: 10.1093/nc/niae006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2023] [Revised: 01/16/2024] [Accepted: 01/23/2024] [Indexed: 02/15/2024] Open
Abstract
Predictive processing theories state that our subjective experience of reality is shaped by a balance of expectations based on previous knowledge about the world (i.e. priors) and confidence in sensory input from the environment. Divergent experiences (e.g. hallucinations and synaesthesia) are likely to occur when there is an imbalance between one's reliance on priors and sensory input. In a novel theoretical model, inspired by both predictive processing and psychological principles, we propose that predictable divergent experiences are associated with natural or environmentally induced prior/sensory imbalances: inappropriately strong or inflexible (i.e. maladaptive) high-level priors (beliefs) combined with low sensory confidence can result in reality discrimination issues, a characteristic of psychosis; maladaptive low-level priors (sensory expectations) combined with high sensory confidence can result in atypical sensory sensitivities and persistent divergent percepts, a characteristic of synaesthesia. Crucially, we propose that whether different divergent experiences manifest with dominantly sensory (e.g. hallucinations) or nonsensory characteristics (e.g. delusions) depends on mental imagery ability, which is a spectrum from aphantasia (absent or weak imagery) to hyperphantasia (extremely vivid imagery). We theorize that imagery is critically involved in shaping the sensory richness of divergent perceptual experience. In sum, to predict a range of divergent perceptual experiences in both clinical and general populations, three factors must be accounted for: a maladaptive use of priors, individual level of confidence in sensory input, and mental imagery ability. These ideas can be expressed formally using nonparametric regression modeling. We provide evidence for our theory from previous work and deliver predictions for future research.
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Affiliation(s)
- Reshanne R Reeder
- Department of Psychology, Institute of Population Health, University of Liverpool, Liverpool L69 3BX, United Kingdom
| | - Giovanni Sala
- Department of Psychology, Institute of Population Health, University of Liverpool, Liverpool L69 3BX, United Kingdom
| | - Tessa M van Leeuwen
- Department of Communication and Cognition, Tilburg School of Humanities and Digital Sciences, Tilburg University, Tilburg, The Netherlands
- Donders Institute for Brain, Cognition and Behaviour, Radboud University, Nijmegen, The Netherlands
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2
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Racey C, Kampoureli C, Bowen-Hill O, Bauer M, Simpson I, Rae C, Del Rio M, Simner J, Ward J. An Open Science MRI Database of over 100 Synaesthetic Brains and Accompanying Deep Phenotypic Information. Sci Data 2023; 10:766. [PMID: 37925503 PMCID: PMC10625562 DOI: 10.1038/s41597-023-02664-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2023] [Accepted: 10/19/2023] [Indexed: 11/06/2023] Open
Abstract
We provide a neuroimaging database consisting of 102 synaesthetic brains using state-of-the-art 3 T MRI protocols from the Human Connectome Project (HCP) which is freely available to researchers. This database consists of structural (T1- and T2-weighted) images together with approximately 24 minutes of resting state data per participant. These protocols are designed to be inter-operable and reproducible so that others can add to the dataset or directly compare it against other normative or special samples. In addition, we provide a 'deep phenotype' of our sample which includes detailed information about each participant's synaesthesia together with associated clinical and cognitive measures. This behavioural dataset, which also includes data from (N = 109) non-synaesthetes, is of importance in its own right and is openly available.
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Affiliation(s)
- Chris Racey
- School of Psychology and Sussex Neuroscience, University of Sussex, Brighton, UK
| | - Christina Kampoureli
- School of Psychology and Sussex Neuroscience, University of Sussex, Brighton, UK
| | - Oscar Bowen-Hill
- School of Psychology and Sussex Neuroscience, University of Sussex, Brighton, UK
| | - Mathilde Bauer
- School of Psychology and Sussex Neuroscience, University of Sussex, Brighton, UK
| | - Ivor Simpson
- School of Engineering and Informatics, University of Sussex, Brighton, UK
| | - Charlotte Rae
- School of Psychology and Sussex Neuroscience, University of Sussex, Brighton, UK
| | - Magda Del Rio
- School of Psychology and Sussex Neuroscience, University of Sussex, Brighton, UK
| | - Julia Simner
- School of Psychology and Sussex Neuroscience, University of Sussex, Brighton, UK
| | - Jamie Ward
- School of Psychology and Sussex Neuroscience, University of Sussex, Brighton, UK.
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3
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Taylor MJ, van Leeuwen TM, Kuja-Halkola R, Lundström S, Larsson H, Lichtenstein P, Bölte S, Neufeld J. Genetic and environmental architecture of synaesthesia and its association with the autism spectrum-a twin study. Proc Biol Sci 2023; 290:20231888. [PMID: 37876199 PMCID: PMC10598415 DOI: 10.1098/rspb.2023.1888] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2023] [Accepted: 09/26/2023] [Indexed: 10/26/2023] Open
Abstract
Synaesthesia is a sensory phenomenon where external stimuli, such as sounds or letters, trigger additional sensations (e.g. colours). Synaesthesia aggregates in families but its heritability is unknown. The phenomenon is more common in people on the autism spectrum compared with the general population and associated with higher autistic traits. Using classical twin design, we assessed the heritability of individual differences in self-reported synaesthesia and the genetic and environmental contributions to their association with autistic traits within a population twin cohort (n = 4262, age = 18 years). We estimated individual differences in synaesthesia to be heritable and influenced by environmental factors not shared between twins. The association between individual differences in synaesthesia and autistic traits was estimated to be predominantly under genetic influence and seemed to be mainly driven by non-social autistic traits (repetitive behaviours, restricted interests and attention to detail). Our study suggests that the link between synaesthesia and autism might reside in shared genetic causes, related to non-social autistic traits such as alterations in perception. Future studies building on these findings may attempt to identify specific groups of genes that influence both autism, synaesthesia and perception.
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Affiliation(s)
- Mark J. Taylor
- Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, 17165 Stockholm, Sweden
| | - Tessa M. van Leeuwen
- Tilburg School of Humanities and Digital Sciences, Department of Communication and Cognition, Tilburg University, 5037 AB Tilburg, The Netherlands
- Donders Institute for Brain, Cognition and Behaviour, Radboud University, 6525 XZ Nijmegen, The Netherlands
| | - Ralf Kuja-Halkola
- Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, 17165 Stockholm, Sweden
| | - Sebastian Lundström
- Gillberg Neuropsychiatry Centre, Centre for Ethics, Law and Mental Health, University of Gothenburg, 405 30 Gothenburg, Sweden
| | - Henrik Larsson
- Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, 17165 Stockholm, Sweden
- School of Medical Sciences, Örebro University, 70281 Örebro, Sweden
| | - Paul Lichtenstein
- Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, 17165 Stockholm, Sweden
| | - Sven Bölte
- Center of Neurodevelopmental Disorders (KIND), Centre for Psychiatry Research, Department of Women's and Children's Health, Karolinska Institutet, Stockholm Health Care Services, Region Stockholm, 11364 Stockholm, Sweden
- Curtin Autism Research Group, Curtin School of Allied Health, Curtin University, WA 66102 Perth, Western Australia
- Child and Adolescent Psychiatry, Stockholm Health Care Services, Region Stockholm, 11364 Stockholm, Sweden
| | - Janina Neufeld
- Center of Neurodevelopmental Disorders (KIND), Centre for Psychiatry Research, Department of Women's and Children's Health, Karolinska Institutet, Stockholm Health Care Services, Region Stockholm, 11364 Stockholm, Sweden
- Swedish Collegium for Advanced Study (SCAS), 75238 Uppsala, Sweden
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Abstract
INTRODUCTION This study determines whether there is a familial aggregation between synaesthesia and two neuropsychiatric conditions (autism and schizophrenia). METHOD We examined the prevalence of autism and schizophrenia among synaesthetes and non-synaesthetic controls, and among their first-degree relatives. RESULTS As predicted, autism occurred at elevated levels among synaesthetes and-we document for the first time-amongst their relatives. This was not found for schizophrenia, where a link may be expected, or in a control condition (type 1 diabetes) where we had no a priori reason to assume a link. Synaesthetes, compared to controls, were also more likely to have other synaesthetes in their family. People with three or more types of synaesthesia were more likely (compared to synaesthetes with fewer types) to have synaesthetic relatives and to report autism in themselves. People with two or more types of synaesthesia (compared to synaesthetes with only one type) were more likely to report familial autism. CONCLUSIONS The results suggest a shared genetic predisposition between synaesthesia and autism, and more extreme synaesthetes may tend to hail from more neurodiverse families.
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Affiliation(s)
- Max Nugent
- School of Psychology University of Sussex, Brighton, UK
| | - Jamie Ward
- School of Psychology University of Sussex, Brighton, UK
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5
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van Leeuwen TM, Wilsson L, Norrman HN, Dingemanse M, Bölte S, Neufeld J. Perceptual processing links autism and synesthesia: A co-twin control study. Cortex 2021; 145:236-249. [PMID: 34763130 DOI: 10.1016/j.cortex.2021.09.016] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2020] [Revised: 05/21/2021] [Accepted: 09/02/2021] [Indexed: 11/19/2022]
Abstract
Synesthesia occurs more commonly in individuals fulfilling criteria for an autism spectrum diagnosis than in the general population. It is associated with autistic traits and autism-related perceptual processing characteristics, including a more detail-focused attentional style and altered sensory sensitivity. In addition, these characteristics correlate with the degree of grapheme-color synesthesia (consistency of grapheme-color associations) in non-synesthetes. We investigated a predominantly non-synesthetic twin sample, including individuals fulfilling criteria for an autism spectrum diagnosis or other neurodevelopmental disorders (n = 65, 14-34 years, 60% female). We modelled linear relationships between the degree of grapheme-color synesthesia and autistic traits, sensory sensitivity, and visual perception, both within-twin pairs (22 pairs) where all factors shared by twins are implicitly controlled (including 50-100% genetics), and across the entire cohort. We found that the degree of grapheme-color synesthesia was associated with autistic traits within the domain of Attention to Details and with sensory hyper-, but not hypo-sensitivity. These associations were stronger within-twin pairs than across the sample. Further, twins with a higher degree of grapheme-color synesthesia were better than their co-twins at identifying fragmented images (Fragmented Pictures Test). This is the first twin study on the association between synesthesia and autism-related perceptual features and traits. The results suggest that investigating these associations within-twin pairs, implicitly adjusting for potential confounding factors shared by twins, is more sensitive than doing so in non-related individuals. Consistent with previous findings, the results suggest an association between the degree of grapheme-color synesthesia and autism-related perceptual features, while utilizing a different measure for sensory sensitivity. The novel finding of enhanced fragmented picture integration in twins with a higher degree of grapheme-color synesthesia challenges the view of a generally more detail-focused attentional style in synesthesia and might be related to enhanced memory or mental imagery in more synesthetic individuals.
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Affiliation(s)
- Tessa M van Leeuwen
- Donders Institute for Brain, Cognition and Behaviour, Radboud University, Nijmegen, the Netherlands; Department of Communication and Cognition, Tilburg School of Humanities and Digital Sciences, Tilburg University, Tilburg, the Netherlands
| | - Lowe Wilsson
- Center of Neurodevelopmental Disorders (KIND), Centre for Psychiatry Research, Department of Women's and Children's Health, Karolinska Institutet & Stockholm Health Care Services, Region Stockholm, Stockholm, Sweden
| | - Hjalmar Nobel Norrman
- Center of Neurodevelopmental Disorders (KIND), Centre for Psychiatry Research, Department of Women's and Children's Health, Karolinska Institutet & Stockholm Health Care Services, Region Stockholm, Stockholm, Sweden
| | - Mark Dingemanse
- Donders Institute for Brain, Cognition and Behaviour, Radboud University, Nijmegen, the Netherlands; Centre for Language Studies, Radboud University, Nijmegen, the Netherlands
| | - Sven Bölte
- Center of Neurodevelopmental Disorders (KIND), Centre for Psychiatry Research, Department of Women's and Children's Health, Karolinska Institutet & Stockholm Health Care Services, Region Stockholm, Stockholm, Sweden; Child and Adolescent Psychiatry, Stockholm Health Care Services, Region Stockholm, Stockholm, Sweden; Curtin Autism Research Group, Curtin School of Allied Health, Curtin University, Perth, WA, Australia
| | - Janina Neufeld
- Center of Neurodevelopmental Disorders (KIND), Centre for Psychiatry Research, Department of Women's and Children's Health, Karolinska Institutet & Stockholm Health Care Services, Region Stockholm, Stockholm, Sweden.
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Berger JJ, Harris IM, Whittingham KM, Terpening Z, Watson JDG. Sharing the load: How a personally coloured calculator for grapheme-colour synaesthetes can reduce processing costs. PLoS One 2021; 16:e0257713. [PMID: 34551015 PMCID: PMC8457480 DOI: 10.1371/journal.pone.0257713] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2020] [Accepted: 09/08/2021] [Indexed: 11/18/2022] Open
Abstract
Synaesthesia refers to a diverse group of perceptions. These unusual perceptions are defined by the experience of concurrents; these are conscious experiences that are catalysed by attention to some normally unrelated stimulus, the inducer. In grapheme-colour synaesthesia numbers, letters, and words can all cause colour concurrents, and these are independent of the actual colour with which the graphemes are displayed. For example, when seeing the numeral '3' a person with synaesthesia might experience green as the concurrent irrespective of whether the numeral is printed in blue, black, or red. As a trait, synaesthesia has the potential to cause both positive and negative effects. However, regardless of the end effect, synaesthesia incurs an initial cost when compared with its equivalent example from normal perception; this is the additional processing cost needed to generate the information on the concurrent. We contend that this cost can be reduced by mirroring the concurrent in the environment. We designed the Digital-Colour Calculator (DCC) app, allowing each user to personalise and select the colours with which it displays its digits; it is the first reported example of a device/approach that leverages the concurrent. In this article we report on the reactions to the DCC for a sample of fifty-three synaesthetes and thirty-five non-synaesthetes. The synaesthetes showed a strong preference for the DCC over its normal counterpart. The non-synaesthetes showed no obvious preference. When using the DCC a subsample of the synaesthete group showed consistent improvement in task speed (around 8%) whereas no synaesthete showed a decrement in their speed.
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Affiliation(s)
- Joshua J. Berger
- Faculty of Medicine and Health, The University of Sydney, Sydney, NSW, Australia
| | - Irina M. Harris
- School of Psychology, Faculty of Science, The University of Sydney, Sydney, NSW, Australia
| | | | - Zoe Terpening
- School of Psychology, Faculty of Science, The University of Sydney, Sydney, NSW, Australia
- Faculty of Medicine and Health, University of New South Wales, Sydney, NSW, Australia
| | - John D. G. Watson
- Faculty of Medicine and Health, The University of Sydney, Sydney, NSW, Australia
- Faculty of Medicine and Health, University of New South Wales, Sydney, NSW, Australia
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7
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Ward J. Synaesthesia as a model system for understanding variation in the human mind and brain. Cogn Neuropsychol 2021; 38:259-278. [PMID: 34266374 DOI: 10.1080/02643294.2021.1950133] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
The aim of this article is to reposition synaesthesia as model system for understanding variation in the construction of the human mind and brain. People with synaesthesia inhabit a remarkable mental world in which numbers can be coloured, words can have tastes, and music is a visual spectacle. Key questions remain unanswered about why it exists, and how the study of synaesthesia might inform theories of the human mind. This article argues we need to rethink synaesthesia as not just representing exceptional experiences, but as a product of an unusual neurodevelopmental cascade from genes to brain to cognition of which synaesthesia is only one outcome. Specifically, differences in the brains of synaesthetes support a distinctive way of thinking (enhanced memory, imagery etc.) and may also predispose towards particular clinical vulnerabilities. In effect, synaesthesia can act as a paradigmatic example of a neuropsychological approach to individual differences.
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Affiliation(s)
- Jamie Ward
- School of Psychology, University of Sussex, Brighton, UK
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8
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Benítez-Burraco A, Progovac L. Language evolution: examining the link between cross-modality and aggression through the lens of disorders. Philos Trans R Soc Lond B Biol Sci 2021; 376:20200188. [PMID: 33745319 PMCID: PMC8059641 DOI: 10.1098/rstb.2020.0188] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/10/2020] [Indexed: 12/12/2022] Open
Abstract
We demonstrate how two linguistic phenomena, figurative language (implicating cross-modality) and derogatory language (implicating aggression), both demand a precise degree of (dis)inhibition in the same cortico-subcortical brain circuits, in particular cortico-striatal networks, whose connectivity has been significantly enhanced in recent evolution. We examine four cognitive disorders/conditions that exhibit abnormal patterns of (dis)inhibition in these networks: schizophrenia (SZ), autism spectrum disorder (ASD), synaesthesia and Tourette's syndrome (TS), with the goal of understanding why the two phenomena altered reactive aggression and altered cross-modality cluster together in these disorders. Our proposal is that enhanced cross-modality (necessary to support language, in particular metaphoricity) was a result, partly a side-effect, of self-domestication (SD). SD targeted the taming of reactive aggression, but reactive impulses are controlled by the same cortico-subcortical networks that are implicated in cross-modality. We further add that this biological process of SD did not act alone, but was engaged in an intense feedback loop with the cultural emergence of early forms of language/grammar, whose high degree of raw metaphoricity and verbal aggression also contributed to increased brain connectivity and cortical control. Consequently, in conjunction with linguistic expressions serving as approximations/'fossils' of the earliest stages of language, these cognitive disorders/conditions serve as confident proxies of brain changes in language evolution, helping us reconstruct certain crucial aspects of early prehistoric languages and cognition, as well as shed new light on the nature of the disorders. This article is part of the theme issue 'Reconstructing prehistoric languages'.
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Affiliation(s)
- Antonio Benítez-Burraco
- Department of Spanish, Linguistics and Theory of Literature (Linguistics), Faculty of Philology, University of Seville, Seville, Spain
| | - Ljiljana Progovac
- Linguistics Program, Department of English, Wayne State University, Detroit, MI, USA
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9
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Jewanski J, Simner J, Day SA, Rothen N, Ward J. Recognizing synesthesia on the international stage: The first scientific symposium on synesthesia (at The International Conference of Physiological Psychology, Paris, 1889). JOURNAL OF THE HISTORY OF THE NEUROSCIENCES 2020; 29:357-384. [PMID: 32407641 DOI: 10.1080/0964704x.2020.1747866] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
At the first ever worldwide international conference of psychology in Paris, 1889, one symposium included a round-table event devoted entirely to the neurodevelopmental condition of synesthesia. Details of this seminal gathering on synesthesia and its international reception have been lost to historical obscurity. A synesthesia study committee emerged from this meeting, as well as a new research tool. Moreover, the scientific findings discussed during this symposium would be echoed over a hundred years later, when a new wave of synesthesia research in the late-twentieth century arose. This article sheds new light on this seminal gathering and aims to answer the following historical questions: Why was synesthesia included in this conference? What science was discussed? Who were the members of the committee and how did they come to be involved? What were their contributions to synesthesia research before, during, and after the conference? What has history shown us about the impact of this symposium on the science of synesthesia?
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Affiliation(s)
- Jörg Jewanski
- Institute of Musicology, University of Vienna , Vienna, Austria
- Department Musikhochschule, University of Münster , Münster, Germany
| | - Julia Simner
- School of Psychology, University of Sussex , Brighton, UK
| | - Sean A Day
- Department of Behavioral and Social Sciences, Trident Technical College , Charleston, South Carolina, USA
| | - Nicolas Rothen
- Faculty of Psychology, Swiss Distance University Institute , Brig, Switzerland
| | - Jamie Ward
- School of Psychology, University of Sussex , Brighton, UK
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10
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van Leeuwen TM, Neufeld J, Hughes J, Ward J. Synaesthesia and autism: Different developmental outcomes from overlapping mechanisms? Cogn Neuropsychol 2020; 37:433-449. [PMID: 32845799 DOI: 10.1080/02643294.2020.1808455] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Synaesthesia, a mixing of the senses, is more common in individuals with autism. Here, we review the evidence for the association between synaesthesia and autism with regard to their genetic background, brain connectivity, perception, cognitive mechanisms and their contribution to exceptional talents. Currently, the overlap between synaesthesia and autism is established most convincingly at the level of alterations in sensory sensitivity and perception, with synaesthetes showing autism-like profiles of sensory sensitivity and a bias towards details in perception. Shared features may include a predominance of local over global connectivity in the brain. When autism and synaesthesia co-occur in the same individual, the chance of developing heightened cognitive and memory abilities is increased. We discuss how the same theoretical models could potentially explain both conditions. Given the evidence, we believe the phenotypical overlap between autism and synaesthesia has been established clearly enough to invite future research to confirm overlapping mechanisms.
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Affiliation(s)
- Tessa M van Leeuwen
- Donders Institute for Brain, Cognition and Behaviour, Radboud University, Nijmegen, the Netherlands
| | - Janina Neufeld
- Center of Neurodevelopmental Disorders (KIND), Centre for Psychiatry Research, Department of Women's and Children's Health, Karolinska Institutet & Stockholm Health Care Services, Region Stockholm, Stockholm, Sweden
| | - James Hughes
- School of Psychology, University of Sussex, Brighton, UK
| | - Jamie Ward
- School of Psychology, University of Sussex, Brighton, UK
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11
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Simner J, Hughes JEA, Sagiv N. Objectum sexuality: A sexual orientation linked with autism and synaesthesia. Sci Rep 2019; 9:19874. [PMID: 31882730 PMCID: PMC6934473 DOI: 10.1038/s41598-019-56449-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2019] [Accepted: 12/06/2019] [Indexed: 01/06/2023] Open
Abstract
Objectum-sexuality (OS) is a sexual orientation which has received little attention in the academic literature. Individuals who identify as OS experience emotional, romantic and/or sexual feelings towards inanimate objects (e.g. a bridge, a statue). We tested 34 OS individuals and 88 controls, and provide the first empirical evidence that OS is linked to two separate neurodevelopmental traits - autism and synaesthesia. We show that OS individuals possess significantly higher rates of diagnosed autism and significantly stronger autistic traits compared to controls, as well as a significantly higher prevalence of synaesthesia, and significant synaesthetic traits inherent in the nature of their attractions. Our results suggest that OS may encapsulate autism and synaesthesia within its phenomenology. Our data speak to debates concerning the biological underpinnings of sexuality, to models of autism and synaesthesia, and to psychological and philosophical models of romantic love.
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Affiliation(s)
- Julia Simner
- School of Psychology, Pevensey Building, University of Sussex, Brighton, BN1 9QJ, UK.
| | - James E A Hughes
- School of Psychology, Pevensey Building, University of Sussex, Brighton, BN1 9QJ, UK
| | - Noam Sagiv
- Centre for Cognitive Neuroscience, College of Health and Life Sciences, Brunel University, London, Uxbridge, UB8 3PN, UK
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12
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Spiller MJ, Harkry L, McCullagh F, Thoma V, Jonas C. Exploring the relationship between grapheme colour-picking consistency and mental imagery. Philos Trans R Soc Lond B Biol Sci 2019; 374:20190023. [PMID: 31630654 DOI: 10.1098/rstb.2019.0023] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Previous research has indicated a potential link between mental imagery and synaesthesia. However, these findings are mainly based on imagery self-report measures and recruitment of self-selected synaesthetes. To avoid issues of self-selection and demand effects, we recruited participants from the general population, rather than synaesthetes specifically, and used colour-picking consistency tests for letters and numbers to assess a 'synaesthete-like' experience. Mental imagery ability and mental rotation ability were assessed using both self-report measures and behavioural assessments. Consistency in colour-picking for letters (but not numbers) was predicted by performance on the visual mental imagery task but not by a mental rotation task or self-report measures. Using the consistency score as a proxy measure of grapheme-colour synaesthesia, we provide more evidence for the suggestion that synaesthetic experience is associated with enhanced mental imagery, even when participants are naive to the research topic. This article is part of a discussion meeting issue 'Bridging senses: novel insights from synaesthesia'.
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Affiliation(s)
| | - Lee Harkry
- School of Psychology, University of East London, London E14 4LZ, UK
| | - Fintan McCullagh
- School of Psychology, University of East London, London E14 4LZ, UK
| | - Volker Thoma
- School of Psychology, University of East London, London E14 4LZ, UK
| | - Clare Jonas
- School of Psychology, University of East London, London E14 4LZ, UK
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