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Favre E, Piveteau M, Babinet MN, Demily C. Extent of magnitude representation deficit and relationship with arithmetic skills in children with 22q11.2DS. Orphanet J Rare Dis 2024; 19:250. [PMID: 38961462 DOI: 10.1186/s13023-024-03263-1] [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: 02/07/2024] [Accepted: 06/21/2024] [Indexed: 07/05/2024] Open
Abstract
BACKGROUND Previous studies have produced conflicting results concerning the extent of magnitude representation deficit and its relationship with arithmetic achievement in children with 22q11.2 deletion syndrome. More specifically, it remains unclear whether deficits are restricted to visuospatial content or are more general and whether they could explain arithmetical impairment. METHODS Fifteen 5- to 12-year-old children with 22q11.2 deletion syndrome and 23 age-matched healthy controls performed a non-symbolic magnitude comparison task. Depending on the trial, participants had to compare stimuli with high or low visuospatial load (visuospatial stimuli or temporal sequence of visual stimuli). The participants also completed a battery of arithmetic skills (ZAREKI-R) and a battery of global cognitive functioning (WISC-V or WPPSI-IV), from which working memory and visuospatial indices were derived. RESULTS Children with 22q11.2DS responded as fast as healthy controls did but received fewer correct responses, irrespective of visuospatial load. In addition, their performance in the non-symbolic magnitude comparison task did not correlate with the ZAREKI total score, while the working memory index did. CONCLUSION Children with 22q11.2DS might suffer from a global magnitude representation deficit rather than a specific deficit due to visuospatial load. However, this deficit alone does not seem to be related to arithmetic achievement. Working memory might be a better concern of interest in favoring arithmetic skills in patients with 22q11.2 deletion syndrome. TRIAL REGISTRATION Clinicaltrials, NCT04373226 . Registered 16 September 2020.
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Affiliation(s)
- Emilie Favre
- Laboratoire EMC, Département de Sciences Cognitives, Psychologie Cognitive et Neuropsychologie, Université Lyon 2, Lyon, France.
| | - Margot Piveteau
- Service de Neuropédiatrie, Hôpital Nord Ouest, Villefranche-Sur-Saône, France
| | - Marie-Noelle Babinet
- CRMR GénoPsy-Lyon, Centre d'Excellence Autisme iMIND & Pôle HU-ADIS, CH le Vinatier, Lyon, France
| | - Caroline Demily
- CRMR GénoPsy-Lyon, Centre d'Excellence Autisme iMIND & Pôle HU-ADIS, CH le Vinatier, CNRS & Université Lyon 1, Lyon, France
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2
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Romeo Z, Dolfi S, D'Amelio M, Mioni G. Duration, numerosity and length processing in healthy ageing and Parkinson's disease. Eur J Ageing 2024; 21:14. [PMID: 38656628 PMCID: PMC11043296 DOI: 10.1007/s10433-024-00807-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/10/2024] [Indexed: 04/26/2024] Open
Abstract
People constantly process temporal, numerical, and length information in everyday activities and interactions with the environment. However, it is unclear whether quantity perception changes during ageing. Previous studies have provided heterogeneous results, sometimes showing an age-related effect on a particular quantity, and other times reporting no differences between young and elderly samples. However, three dimensions were never compared within the same study. Here, we conducted two experiments with the aim of investigating the processing of duration, numerosity and length in both healthy and pathological ageing. The experimental paradigm consisted of three bisection tasks in which participants were asked to judge whether the presented stimulus (i.e. a time interval, a group of dots, or a line) was more similar to the short/few or long/many standards. The first study recruited healthy young and elderly participants, while the second recruited healthy elderly participants and patients with Parkinson's disease, a clinical condition commonly associated with temporal impairments. The results of both experiments showed that discrimination precision differed between domains in all groups, with higher precision in the numerosity task and lower sensitivity in judging duration. Furthermore, while discrimination abilities were affected in healthy elderly and, even more so, in Parkinson's disease group, no domain-specific impairments emerged. According to our research, reduced discrimination precision might be explained by an alteration of a single system for all quantities or by an age-related general cognitive decline.
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Affiliation(s)
- Z Romeo
- Department of General Psychology, University of Padova, Via Venezia, 8, 35131, Padua, Italy.
- Neuroscience Institute, National Research Council (CNR), Padua, Italy.
| | - S Dolfi
- Department of Developmental Psychology and Socialization, University of Padova, Padua, Italy
| | | | - G Mioni
- Department of General Psychology, University of Padova, Via Venezia, 8, 35131, Padua, Italy.
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3
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Johari K, Tabari F, Desai RH. Right frontal HD-tDCS reveals causal involvement of time perception networks in temporal processing of concepts. Sci Rep 2023; 13:16658. [PMID: 37789056 PMCID: PMC10547783 DOI: 10.1038/s41598-023-43416-z] [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: 05/08/2023] [Accepted: 09/23/2023] [Indexed: 10/05/2023] Open
Abstract
Evidence suggests that perceptual and action related features of concepts are grounded in the corresponding sensory-motor networks in the human brain. However, less is known about temporal features of event concepts (e.g., a lecture) and whether they are grounded in time perception networks. We examined this question by stimulating the right dorsolateral prefrontal cortex (rDLPFC)-a part of time perception network-using HD-tDCS and subsequently recording EEG while participants performed semantic and time perception tasks. Semantic tasks were composed of event noun duration judgment (EDur), object noun size judgement (OSize), event (EVal) and object noun valence judgement. In the time perception task, participants judged the durations of pure tones. Results showed that cathodal stimulation accelerated responses for time perception task and decreased the magnitude of global field power (GFP) compared to sham stimulation. Semantic tasks results revealed that cathodal, but not sham, stimulation significantly decreased GFP for EDur relative to OSize, and to EVal. These findings provide first causal evidence that temporal features of event words are grounded in the rDLPFC as part of the temporal cognition network and shed light on the conceptual processing of time.
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Affiliation(s)
- Karim Johari
- Human Neurophysiology and Neuromodulation Laboratory, Department of Communication Science and Disorders, Louisiana State University, 86 Hatcher Hall, Field House Drive, Baton Rouge, LA, 70803, USA.
| | - Fatemeh Tabari
- Human Neurophysiology and Neuromodulation Laboratory, Department of Communication Science and Disorders, Louisiana State University, 86 Hatcher Hall, Field House Drive, Baton Rouge, LA, 70803, USA
| | - Rutvik H Desai
- Department of Psychology, University of South Carolina, Columbia, SC, USA
- Institute for Mind and Brain, University of South Carolina, Columbia, SC, USA
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4
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Cona G, Wiener M, Allegrini F, Scarpazza C. Gradient Organization of Space, Time, and Numbers in the Brain: A Meta-analysis of Neuroimaging Studies. Neuropsychol Rev 2023:10.1007/s11065-023-09609-z. [PMID: 37594695 DOI: 10.1007/s11065-023-09609-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2022] [Accepted: 07/07/2023] [Indexed: 08/19/2023]
Abstract
In this study, we ran a meta-analysis of neuroimaging studies to pinpoint the neural regions that are commonly activated across space, time, and numerosity, and we tested the existence of gradient transitions among these magnitude representations in the brain. Following PRISMA guidelines, we included in the meta-analysis 112 experiments (for space domain), 114 experiments (time domain), and 115 experiments (numerosity domain), and we used the activation likelihood estimation method. We found a system of brain regions that was commonly recruited in all the three magnitudes, which included bilateral insula, the supplementary motor area (SMA), the right inferior frontal gyrus, and bilateral intraparietal sulci. Gradiental transitions between different magnitudes were found along all these regions but insulae, with space and numbers leading to gradients mainly over parietal regions (and SMA) whereas time and numbers mainly over frontal regions. These findings provide evidence for the GradiATOM theory (Gradient Theory of Magnitude), suggesting that spatial proximity given by overlapping activations and gradients is a key aspect for efficient interactions and integrations among magnitudes.
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Affiliation(s)
- Giorgia Cona
- Department of General Psychology, University of Padua, Via Venezia 8, 35131, Padua, Italy.
- Padova Neuroscience Center, University of Padua, Padua, Italy.
- Department of Neuroscience, University of Padua, Padua, Italy.
| | - Martin Wiener
- Department of Psychology, George Mason University, Fairfax, VA, USA
| | - Francesco Allegrini
- Department of General Psychology, University of Padua, Via Venezia 8, 35131, Padua, Italy
| | - Cristina Scarpazza
- Department of General Psychology, University of Padua, Via Venezia 8, 35131, Padua, Italy
- IRCSS San Camillo Hospital, Venice, Italy
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5
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Gennari G, Dehaene S, Valera C, Dehaene-Lambertz G. Spontaneous supra-modal encoding of number in the infant brain. Curr Biol 2023; 33:1906-1915.e6. [PMID: 37071994 DOI: 10.1016/j.cub.2023.03.062] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2022] [Revised: 01/30/2023] [Accepted: 03/21/2023] [Indexed: 04/20/2023]
Abstract
The core knowledge hypothesis postulates that infants automatically analyze their environment along abstract dimensions, including numbers. According to this view, approximate numbers should be encoded quickly, pre-attentively, and in a supra-modal manner by the infant brain. Here, we directly tested this idea by submitting the neural responses of sleeping 3-month-old infants, measured with high-density electroencephalography (EEG), to decoders designed to disentangle numerical and non-numerical information. The results show the emergence, in approximately 400 ms, of a decodable number representation, independent of physical parameters, that separates auditory sequences of 4 vs. 12 tones and generalizes to visual arrays of 4 vs. 12 objects. Thus, the infant brain contains a number code that transcends sensory modality, sequential or simultaneous presentation, and arousal state.
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Affiliation(s)
- Giulia Gennari
- Cognitive Neuroimaging Unit U992, Institut National de la Santé et de la Recherche Médicale, Commissariat à l'Énergie Atomique et aux Énergies Alternatives, Direction de la Recherche Fondamentale/Institut Joliot, Centre National de la Recherche Scientifique ERL9003, NeuroSpin Center, Université Paris-Saclay, 91191 Gif-sur-Yvette, France; Neuroscience Institute, New York University Grossman School of Medicine, New York, NY 10016, USA.
| | - Stanislas Dehaene
- Cognitive Neuroimaging Unit U992, Institut National de la Santé et de la Recherche Médicale, Commissariat à l'Énergie Atomique et aux Énergies Alternatives, Direction de la Recherche Fondamentale/Institut Joliot, Centre National de la Recherche Scientifique ERL9003, NeuroSpin Center, Université Paris-Saclay, 91191 Gif-sur-Yvette, France; Collège de France, Université Paris Sciences Lettres (PSL), 75005 Paris, France
| | - Chanel Valera
- Cognitive Neuroimaging Unit U992, Institut National de la Santé et de la Recherche Médicale, Commissariat à l'Énergie Atomique et aux Énergies Alternatives, Direction de la Recherche Fondamentale/Institut Joliot, Centre National de la Recherche Scientifique ERL9003, NeuroSpin Center, Université Paris-Saclay, 91191 Gif-sur-Yvette, France
| | - Ghislaine Dehaene-Lambertz
- Cognitive Neuroimaging Unit U992, Institut National de la Santé et de la Recherche Médicale, Commissariat à l'Énergie Atomique et aux Énergies Alternatives, Direction de la Recherche Fondamentale/Institut Joliot, Centre National de la Recherche Scientifique ERL9003, NeuroSpin Center, Université Paris-Saclay, 91191 Gif-sur-Yvette, France
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6
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Aulet LS, Lourenco SF. No intrinsic number bias: Evaluating the role of perceptual discriminability in magnitude categorization. Dev Sci 2023; 26:e13305. [PMID: 35851738 DOI: 10.1111/desc.13305] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2021] [Revised: 04/13/2022] [Accepted: 07/05/2022] [Indexed: 01/29/2023]
Abstract
Accumulating evidence suggests that there is a spontaneous preference for numerical, compared to non-numerical (e.g., cumulative surface area), information. However, given a paucity of research on the perception of non-numerical magnitudes, it is unclear whether this preference reflects a specific bias towards number, or a general bias towards the more perceptually discriminable dimension (i.e., number). Here, we found that when the number and area of visual dot displays were matched in mathematical ratio, number was more perceptually discriminable than area in both adults and children. Moreover, both adults and children preferentially categorized these ratio-matched stimuli based on number, consistent with previous work. However, when number and area were matched in perceptual discriminability, a different pattern of results emerged. In particular, children preferentially categorized stimuli based on area, suggesting that children's previously observed number bias may be due to a mismatch in the perceptual discriminability of number and area, not an intrinsic salience of number. Interestingly, adults continued to categorize the displays on the basis of number. Altogether, these findings suggest a dominant role for area during childhood, refuting the claim that number is inherently and uniquely salient. Yet they also reveal an increased salience of number that emerges over development. Potential explanations for this developmental shift are discussed. RESEARCH HIGHLIGHTS: Previous work found that children and adults spontaneously categorized dot array stimuli by number, over other magnitudes (e.g., area), suggesting number is uniquely salient. However, here we found that when number and area were matched by ratio, as in prior work, number was significantly more perceptually discriminable than area. When number and area were made equally discriminable ('perceptually-matched'), children, contra adults, spontaneously categorized stimuli by area over number (and other non-numerical magnitudes). These findings suggest that area may be uniquely salient early in childhood, with the previously-observed number bias not emerging until later in development.
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Affiliation(s)
- Lauren S Aulet
- Department of Psychology, Carnegie Mellon University, Pittsburgh, Pennsylvania, USA
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7
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How many seconds was that? Teaching children about time does not refine their ability to track durations. Cognition 2023; 235:105410. [PMID: 36848703 DOI: 10.1016/j.cognition.2023.105410] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2022] [Revised: 01/09/2023] [Accepted: 02/13/2023] [Indexed: 02/27/2023]
Abstract
Over development, children acquire symbols to represent abstract concepts such as time and number. Despite the importance of quantity symbols, it is unknown how acquiring these symbols impacts one's ability to perceive quantities (i.e., nonsymbolic representations). While it has been proposed that learning symbols shapes nonsymbolic quantitative abilities (i.e., the refinement hypothesis), this hypothesis has been understudied, especially in the domain of time. Moreover, the majority of research in support of this hypothesis has been correlational in nature, and thus, experimental manipulations are critical for determining whether this relation is causal. In the present study, kindergarteners and first graders (N = 154) who have yet to learn about temporal symbols in school completed a temporal estimation task during which they were either (1) trained on temporal symbols and effective timing strategies ("2 s" and counting on the beat), (2) trained on temporal symbols only ("2 s"), or (3) participated in a control training. Children's nonsymbolic and symbolic timing abilities were assessed before and after training. Results revealed a correlation between children's nonsymbolic and symbolic timing abilities at pre-test (when controlling for age), indicating this relation exists prior to formal classroom instruction on temporal symbols. Notably, we found no support for the refinement hypothesis, as learning temporal symbols did not impact children's nonsymbolic timing abilities. Implications and future directions are discussed.
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8
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Children and adults rely on different heuristics for estimation of durations. Sci Rep 2023; 13:1077. [PMID: 36658160 PMCID: PMC9852441 DOI: 10.1038/s41598-023-27419-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2022] [Accepted: 01/02/2023] [Indexed: 01/20/2023] Open
Abstract
Time is a uniquely human yet culturally ubiquitous concept acquired over childhood and provides an underlying dimension for episodic memory and estimating durations. Because time, unlike distance, lacks a sensory representation, we hypothesized that subjects at different ages attribute different meanings to it when comparing durations; pre-kindergarten children compare the density of events, while adults use the concept of observer-independent absolute time. We asked groups of pre-kindergarteners, school-age children, and adults to compare the durations of an "eventful" and "uneventful" video, both 1-minute long but durations unknown to subjects. In addition, participants were asked to express the durations of both videos non-verbally with simple hand gestures. Statistical analysis has revealed highly polarized temporal biases in each group, where pre-kindergarteners estimated the duration of the eventful video as "longer." In contrast, the school-age group of children and adults claimed the same about the uneventful video. The tendency to represent temporal durations with a horizontal hand gesture was evident among all three groups, with an increasing prevalence with age. These results support the hypothesis that pre-kindergarten-age children use heuristics to estimate time, and they convert from availability to sampling heuristics between pre-kindergarten and school age.
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9
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Gazes RP, Templer VL, Lazareva OF. Thinking about order: a review of common processing of magnitude and learned orders in animals. Anim Cogn 2023; 26:299-317. [PMID: 36369418 DOI: 10.1007/s10071-022-01713-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2022] [Revised: 11/03/2022] [Accepted: 11/04/2022] [Indexed: 11/13/2022]
Abstract
Rich behavioral and neurobiological evidence suggests cognitive and neural overlap in how quantitatively comparable dimensions such as quantity, time, and space are processed in humans and animals. While magnitude domains such as physical magnitude, time, and space represent information that can be quantitatively compared (4 "is half of" 8), they also represent information that can be organized ordinally (1→2→3→4). Recent evidence suggests that the common representations seen across physical magnitude, time, and space domains in humans may be due to their common ordinal features rather than their common quantitative features, as these common representations appear to extend beyond magnitude domains to include learned orders. In this review, we bring together separate lines of research on multiple ordinal domains including magnitude-based and learned orders in animals to explore the extent to which there is support for a common cognitive process underlying ordinal processing. Animals show similarities in performance patterns across natural quantitatively comparable ordered domains (physical magnitude, time, space, dominance) and learned orders (acquired through transitive inference or simultaneous chaining). Additionally, they show transfer and interference across tasks within and between ordinal domains that support the theory of a common ordinal representation across domains. This review provides some support for the development of a unified theory of ordinality and suggests areas for future research to better characterize the extent to which there are commonalities in cognitive processing of ordinal information generally.
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Affiliation(s)
- Regina Paxton Gazes
- Department of Psychology and Program in Animal Behavior, Bucknell University, Lewisburg, PA, USA.
| | | | - Olga F Lazareva
- Department of Psychology and Neuroscience, Drake University, Des Moines, IA, USA
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10
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Tsouli A, Harvey BM, Hofstetter S, Cai Y, van der Smagt MJ, Te Pas SF, Dumoulin SO. The role of neural tuning in quantity perception. Trends Cogn Sci 2021; 26:11-24. [PMID: 34702662 DOI: 10.1016/j.tics.2021.10.004] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Revised: 10/01/2021] [Accepted: 10/04/2021] [Indexed: 11/16/2022]
Abstract
Perception of quantities, such as numerosity, timing, and size, is essential for behavior and cognition. Accumulating evidence demonstrates neurons processing quantities are tuned, that is, have a preferred quantity amount, not only for numerosity, but also other quantity dimensions and sensory modalities. We argue that quantity-tuned neurons are fundamental to understanding quantity perception. We illustrate how the properties of quantity-tuned neurons can underlie a range of perceptual phenomena. Furthermore, quantity-tuned neurons are organized in distinct but overlapping topographic maps. We suggest that this overlap in tuning provides the neural basis for perceptual interactions between different quantities, without the need for a common neural representational code.
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Affiliation(s)
- Andromachi Tsouli
- Department of Experimental Psychology, Helmholtz Institute, Utrecht University, Utrecht, The Netherlands
| | - Ben M Harvey
- Department of Experimental Psychology, Helmholtz Institute, Utrecht University, Utrecht, The Netherlands
| | - Shir Hofstetter
- The Spinoza Centre for Neuroimaging, Amsterdam, The Netherlands
| | - Yuxuan Cai
- The Spinoza Centre for Neuroimaging, Amsterdam, The Netherlands; Department of Experimental and Applied Psychology, VU University, Amsterdam, The Netherlands
| | - Maarten J van der Smagt
- Department of Experimental Psychology, Helmholtz Institute, Utrecht University, Utrecht, The Netherlands
| | - Susan F Te Pas
- Department of Experimental Psychology, Helmholtz Institute, Utrecht University, Utrecht, The Netherlands
| | - Serge O Dumoulin
- Department of Experimental Psychology, Helmholtz Institute, Utrecht University, Utrecht, The Netherlands; The Spinoza Centre for Neuroimaging, Amsterdam, The Netherlands; Department of Experimental and Applied Psychology, VU University, Amsterdam, The Netherlands; Netherlands Institute for Neuroscience, Royal Netherlands Academy of Sciences, Amsterdam, The Netherlands.
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11
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Application of an abstract concept across magnitude dimensions by fish. Sci Rep 2020; 10:16935. [PMID: 33037309 PMCID: PMC7547013 DOI: 10.1038/s41598-020-74037-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2020] [Accepted: 09/22/2020] [Indexed: 11/26/2022] Open
Abstract
Mastering relational concepts and applying them to different contexts presupposes abstraction capacities and implies a high level of cognitive sophistication. One way to investigate extrapolative abilities is to assess cross-dimensional application of an abstract relational magnitude rule to new domains. Here we show that angelfish initially trained to choose either the shorter of two lines in a spatial task (line-length discrimination task) or the array with “fewer” items (numerical discrimination task) spontaneously transferred the learnt rule to novel stimuli belonging to the previously unseen dimension demonstrating knowledge of the abstract concept of “smaller”. Our finding challenges the idea that the ability to master abstract magnitude concepts across domains is unique to humans and suggests that the circuits involved in rule learning and magnitude processing might be evolutionary conserved.
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12
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Perini F, Powell T, Watt SJ, Downing PE. Neural representations of haptic object size in the human brain revealed by multivoxel fMRI patterns. J Neurophysiol 2020; 124:218-231. [PMID: 32519597 DOI: 10.1152/jn.00160.2020] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
The brain must interpret sensory input from diverse receptor systems to estimate object properties. Much has been learned about the brain mechanisms behind these processes in vision, but our understanding of haptic perception remains less clear. Here we examined haptic judgments of object size, which require integrating multiple cutaneous and proprioceptive afferent signals, as a model problem. To identify candidate human brain regions that support this process, participants (n = 16) in an event-related functional MRI experiment grasped objects to categorize them as one of four sizes. Object sizes were calibrated psychophysically to be equally distinct for each participant. We applied representational similarity logic to whole brain, multivoxel searchlight analyses to identify brain regions that exhibit size-relevant voxelwise activity patterns. Of particular interest was to identify regions for which more similar sizes produce more similar patterns of activity, which constitutes evidence of a metric size code. Regions of the intraparietal sulcus and the lateral prefrontal cortex met this criterion, both within hands and across hands. We suggest that these regions compute representations of haptic size that abstract over the specific peripheral afferent signals generated in a grasp. Results of a matched visual size task, performed by the same participants and analyzed in the same fashion, identified similar regions, indicating that these representations may be partly modality general. We consider these results with respect to perspectives on magnitude estimation in general and to computational views on perceptual signal integration.NEW & NOTEWORTHY Our understanding of the neural basis of haptics (perceiving the world through touch) remains incomplete. We used functional MRI to study human haptic judgments of object size, which require integrating multiple afferent signals. Multivoxel pattern analyses identified intraparietal and prefrontal regions that encode size haptically in a metric and hand-invariant fashion. Effector-independent haptic size estimates are useful on their own and in combination with other sensory estimates for a variety of perceptual and motor tasks.
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Affiliation(s)
- Francesca Perini
- Centre for Sleep and Cognition, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - Thomas Powell
- Netherlands Applied Science Organisation (TNO), Oude Waalsdorperweg 63, Den Haag, The Netherlands
| | - Simon J Watt
- School of Psychology, Bangor University, Bangor, United Kingdom
| | - Paul E Downing
- School of Psychology, Bangor University, Bangor, United Kingdom
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