Automatic Processing of Numerosity in Human Neocortex Evidenced by Occipital and Parietal Neuromagnetic Responses

AbstractHumans and other animal species are endowed with the ability to sense, represent, and mentally manipulate the number of items in a set without needing to count them. One central hypothesis is that this ability relies on an automated functional system dedicated to numerosity, the perception of the discrete numerical magnitude of a set of items. This system has classically been associated with intraparietal regions, however accumulating evidence in favor of an early visual number sense calls into question the functional role of parietal regions in numerosity processing. Targeting specifically numerosity among other visual features in the earliest stages of processing requires high temporal and spatial resolution. We used frequency-tagged magnetoencephalography (MEG) to investigate the early automatic processing of numerical magnitudes and measured the steady-state brain responses specifically evoked by numerical and other visual changes in the visual scene. The neuromagnetic responses showed implicit discrimination of numerosity, total occupied area, and convex hull. The source reconstruction corresponding to the implicit discrimination responses showed common and separate sources along the ventral and dorsal visual pathways. Occipital sources attested the perceptual salience of numerosity similarly to both other implicitly discriminable visual features. Crucially, we found parietal responses uniquely associated with numerosity discrimination, showing automatic processing of numerosity in the parietal cortex, even when not relevant to the task. Taken together, these results provide further insights into the functional roles of parietal and occipital regions in numerosity encoding along the visual hierarchy.Significance StatementApproximating the number of items in a set has been identified as a building block of mathematical cognition but the processing of numerosity is not fully understood. The natural correlation between numerosity and other visual features makes it difficult to test whether the number of items is a perceptual primitive or whether it needs to be recombined at a higher level. We used frequency-tagged magnetoencephalography to localize the implicit discrimination of numerosity within the visual hierarchy. We found that numerosity yielded occipital responses, supporting that the human visual system can grasp it at a single glance. Crucially, numerosity also yielded specific parietal responses, showing that numerosity is a perceptual primitive with a unique automatic involvement of parietal cortex.

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Developmental Dyscalculia in Adults: Beyond Numerical Magnitude Impairment

Journal of Learning Disabilities ◽

10.1177/0022219417732338 ◽

2017 ◽

Vol 51 (6) ◽

pp. 600-611 ◽

Cited By ~ 8

Author(s):

Alice De Visscher ◽

Marie-Pascale Noël ◽

Mauro Pesenti ◽

Valérie Dormal

Keyword(s):

Mental Representation ◽

Healthy Adults ◽

Numerical Magnitude ◽

Developmental Dyscalculia ◽

Common System ◽

The Core ◽

Magnitude Processing ◽

Core Deficit ◽

Face Categorization ◽

Numerical Magnitudes

Numerous studies have tried to identify the core deficit of developmental dyscalculia (DD), mainly by assessing a possible deficit of the mental representation of numerical magnitude. Research in healthy adults has shown that numerosity, duration, and space share a partly common system of magnitude processing and representation. However, in DD, numerosity processing has until now received much more attention than the processing of other non-numerical magnitudes. To assess whether or not the processing of non-numerical magnitudes is impaired in DD, the performance of 15 adults with DD and 15 control participants was compared in four categorization tasks using numerosities, lengths, durations, and faces (as non-magnitude-based control stimuli). Results showed that adults with DD were impaired in processing numerosity and duration, while their performance in length and face categorization did not differ from controls’ performance. Our findings support the idea of a nonsymbolic magnitude deficit in DD, affecting numerosity and duration processing but not length processing.

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Imaging Informational Conflict: A Functional Magnetic Resonance Imaging Study of Numerical Stroop

Journal of Cognitive Neuroscience ◽

10.1162/jocn.2006.18.12.2049 ◽

2006 ◽

Vol 18 (12) ◽

pp. 2049-2062 ◽

Cited By ~ 42

Author(s):

J. Tang ◽

H. D. Critchley ◽

D. E. Glaser ◽

R. J. Dolan ◽

B. Butterworth

Keyword(s):

Imaging Study ◽

Distance Effect ◽

Irrelevant Information ◽

Numerical Magnitude ◽

Neural Basis ◽

Neural Fate ◽

Numerical Magnitudes ◽

Informational Conflict ◽

Task Irrelevant ◽

Theoretical Issues

We employed a parametric version of the comparison Stroop paradigm to investigate the processing of numerical magnitude and physical size under task-relevant and -irrelevant conditions to investigate two theoretical issues: (1) What is the neural fate of task-irrelevant information? (2) What is the neural basis of the resolution of the conflict between task-relevant and -irrelevant information? We show in 18 healthy adults that numerical magnitudes of numbers call for higher processing requirements than physical sizes. The enhanced activation elicited by numerical magnitudes is not modulated by task relevance, indicating autonomous processing. Moreover, the normal behavioral distance effect when the numerical dimension is task relevant and reversed distance effect when it is not show that autonomous processing fully encodes numerical magnitudes. Conflict trials elicited greater activation in bilateral inferior frontal gyri, right middle frontal gyri, and right superior frontal gyri. We postulate two sources to the conflict, namely, at cognitive and response levels.

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Feature-Specific Neural Reactivation during Episodic Memory

10.1101/622837 ◽

2019 ◽

Author(s):

Michael B. Bone ◽

Fahad Ahmad ◽

Bradley R. Buchsbaum

Keyword(s):

Frontal Cortex ◽

Visual Features ◽

Semantic Features ◽

Low Level ◽

Visual Hierarchy ◽

Strict Interpretation ◽

Novel Approach ◽

High Level ◽

Hierarchical Representations

AbstractWhen recalling an experience of the past, many of the component features of the original episode may be, to a greater or lesser extent, reconstructed in the mind’s eye. There is strong evidence that the pattern of neural activity that occurred during an initial perceptual experience is recreated during episodic recall (neural reactivation), and that the degree of reactivation is correlated with the subjective vividness of the memory. However, while we know that reactivation occurs during episodic recall, we have lacked a way of precisely characterizing the contents—in terms of its featural constituents—of a reactivated memory. Here we present a novel approach, feature-specific informational connectivity (FSIC), that leverages hierarchical representations of image stimuli derived from a deep convolutional neural network to decode neural reactivation in fMRI data collected while participants performed an episodic recall task. We show that neural reactivation associated with low-level visual features (e.g. edges), high-level visual features (e.g. facial features), and semantic features (e.g. “terrier”) occur throughout the dorsal and ventral visual streams and extend into the frontal cortex. Moreover, we show that reactivation of both low- and high-level visual features correlate with the vividness of the memory, whereas only reactivation of low-level features correlates with recognition accuracy when the lure and target images are semantically similar. In addition to demonstrating the utility of FSIC for mapping feature-specific reactivation, these findings resolve the relative contributions of low- and high-level features to the vividness of visual memories, clarify the role of the frontal cortex during episodic recall, and challenge a strict interpretation the posterior-to-anterior visual hierarchy.

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Attention mediates the influence of numerical magnitude on temporal processing

Scientific Reports ◽

10.1038/s41598-021-90466-2 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Anuj Shukla ◽

Raju S. Bapi

Keyword(s):

Temporal Processing ◽

Processing System ◽

Human Cognition ◽

Numerical Magnitude ◽

Comparison Task ◽

Domain Interaction ◽

Domain Specific ◽

Magnitude Processing ◽

Cross Domain ◽

Numerical Magnitudes

AbstractThe processing of time and numbers has been fundamental to human cognition. One of the prominent theories of magnitude processing, a theory of magnitude (ATOM), suggests that a generalized magnitude system processes space, time, and numbers; thereby, the magnitude dimensions could potentially interact with one another. However, more recent studies have found support for domain-specific magnitude processing and argued that the magnitudes related to time and number are processed through distinct mechanisms. Such mixed findings have raised questions about whether these magnitudes are processed independently or share a common processing mechanism. In the present study, we examine the influence of numerical magnitude on temporal processing. To investigate, we conducted two experiments using a temporal comparison task, wherein we presented positive and negative numerical magnitudes (large and small) in a blocked (Experiment-1) and intermixed manner (Experiment-2). Results from experiment-1 suggest that numerical magnitude affects temporal processing only in positive numbers but not for negative numbers. Further, results from experiment-2 indicate that the polarity (positive and negative) of the numbers influences temporal processing instead of the numerical magnitude itself. Overall, the current study seems to suggest that cross-domain interaction of magnitudes arises from attentional mechanisms and may not need to posit a common magnitude processing system.

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Correlates of social awareness in the visual prosody of growing children

Laboratory Phonology Journal of the Association for Laboratory Phonology ◽

10.1515/labphon.2011.014 ◽

2011 ◽

Vol 2 (2) ◽

Cited By ~ 3

Author(s):

Marc Swerts

Keyword(s):

Facial Expressions ◽

Communication Systems ◽

Negative Emotion ◽

Child Behaviour ◽

Social Awareness ◽

Visual Features ◽

Experimental Paradigm ◽

Central Hypothesis ◽

Visual Prosody ◽

Auditory Features

AbstractThis article focuses on how growing children use prosody for communicative purposes. Prosody refers to the set of expressive features that do not so much determine what speakers say, but rather how they say it. It includes both auditory features, such as intonation and tempo, and visual features, such as facial expressions. Our central hypothesis is that children, as they grow older, become more socially aware — a process which is reflected in the way they express themselves in prosody. To this end, we present the results of three studies that focus on how children use such features (1) to mark their level of uncertainty, (2) to signal a positive or negative emotion, and (3) to show whether they are being truthful or not. All the studies use a game-based experimental paradigm that is especially suited for analyses of child behaviour. The approach combines controlled elicitations of spontaneous interactions with perception tests that explore how children's expressions are being interpreted. Results of such studies are relevant for pedagogical and diagnostic purposes, and will lead to improvements in child-directed communication systems.

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From what we perceive to what we remember: Characterizing representational dynamics of visual memorability

10.1101/049700 ◽

2016 ◽

Cited By ~ 4

Author(s):

Seyed-Mahdi Khaligh-Razavi ◽

Wilma A. Bainbridge ◽

Dimitrios Pantazis ◽

Aude Oliva

Keyword(s):

Neural Dynamics ◽

Visual Features ◽

Memory Encoding ◽

Low Level ◽

Brain Responses ◽

Neural Processes ◽

Neural Bases ◽

Spatio Temporal ◽

High Level

AbstractNot all visual memories are equal—some endure in our minds, while others quickly disappear. Recent behavioral work shows we can reliably predict which images will be remembered. This image property is called memorability. Memorability is intrinsic to an image, robust across observers, and unexplainable by low-level visual features. However, its neural bases and relation with perception and memory remain unknown. Here we characterize the representational dynamics of memorability using magnetoencephalography (MEG). We find memorability is indexed by brain responses starting at 218ms for faces and 371ms for scenes—later than classical early face/scene discrimination perceptual signals, yet earlier than the late memory encoding signal observed at ~700ms. The results show memorability is a high-level image property whose spatio-temporal neural dynamics are different from those of memory encoding. Together, this work brings new insights into the underlying neural processes of the transformation from what we perceive to what we remember.

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Enhanced deviant responses in patterned relative to random sound sequences

10.1101/214031 ◽

2017 ◽

Author(s):

Rosy Southwell ◽

Maria Chait

Keyword(s):

Human Brain ◽

Orbitofrontal Cortex ◽

Sensory Input ◽

Automatic Processing ◽

Specific Pattern ◽

Visual Task ◽

Brain Responses ◽

Temporal Pole ◽

Incoming Information ◽

Preceding Context

AbstractHow are brain responses to deviant events affected by the statistics of the preceding context? We recorded electroencephalography (EEG) brain responses to frequency deviants in matched, regularly-patterned (REG) versus random (RAND) tone-pip sequences. Listeners were naïve and distracted by an incidental visual task. Stimuli were very rapid so as to limit conscious reasoning about the sequence order and tap automatic processing of regularity.Deviants within REG sequences evoked a substantially larger response (by 71%) than matched deviants in RAND sequences from 80 ms after deviant onset. This effect was underpinned by distinct sources in right temporal pole and orbitofrontal cortex in addition to the standard bilateral temporal and right pre-frontal network for generic frequency deviance-detection. These findings demonstrate that the human brain rapidly acquires a detailed representation of regularities within the sensory input and evaluates incoming information according to the context established by the specific pattern.

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Strategy variability in numerosity comparison task: a study in young and older adults

Open Psychology ◽

10.1515/psych-2018-0011 ◽

2019 ◽

Vol 1 (1) ◽

pp. 152-167 ◽

Cited By ~ 7

Author(s):

Angélique Roquet ◽

Patrick Lemaire

Keyword(s):

Older Adults ◽

Visual Features ◽

Verbal Protocols ◽

Comparison Task ◽

Numerosity Discrimination ◽

Trial Solution ◽

Age Related ◽

Single Strategy ◽

Trial Basis ◽

And Performance

AbstractWe investigated strategies used by young and older adults in dot comparison tasks to further our understanding of mechanisms underlying numerosity discrimination and age-related differences therein. The participants were shown a series of two dot collections and asked to select the largest collection. Analyses of verbal protocols collected on each trial, solution times, and percentages of errors documented the strategy repertoire and strategy distribution in young and older adults. Based on visual features of dot collections, both young and older adults used a set of 9 strategies and selected strategies on a trial-by-trial basis. The findings also documented age-related differences (i.e., strategy preferences) and similarities (e.g., number of strategies used by individuals) in strategies and performance. Strategy variability found here has important implications for understanding numerosity comparison and contrasts with previous findings suggesting that participants use a single strategy when they compare dot collections.

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Asymmetric Processing of Numerical and Nonnumerical Magnitudes in the Brain: An fMRI Study

Journal of Cognitive Neuroscience ◽

10.1162/jocn_a_00887 ◽

2016 ◽

Vol 28 (1) ◽

pp. 166-176 ◽

Cited By ~ 18

Author(s):

Tali Leibovich ◽

Stephan E. Vogel ◽

Avishai Henik ◽

Daniel Ansari

Keyword(s):

Numerical Magnitude ◽

Comparison Task ◽

Brain Areas ◽

Surface Areas ◽

Fmri Study ◽

Numerical Magnitudes ◽

The Right ◽

Task Irrelevant ◽

The Brain

It is well established that, when comparing nonsymbolic magnitudes (e.g., dot arrays), adults can use both numerical (i.e., the number of items) and nonnumerical (density, total surface areas, etc.) magnitudes. It is less clear which of these magnitudes is more salient or processed more automatically. In this fMRI study, we used a nonsymbolic comparison task to ask if different brain areas are responsible for the automatic processing of numerical and nonnumerical magnitudes, when participants were instructed to attend to either the numerical or the nonnumerical magnitudes of the same stimuli. An interaction of task (numerical vs. nonnumerical) and congruity (congruent vs. incongruent) was found in the right TPJ. Specifically, this brain region was more strongly activated during numerical processing when the nonnumerical magnitudes were negatively correlated with numerosity (incongruent trials). In contrast, such an interference effect was not evident during nonnumerical processing when the task-irrelevant numerical magnitude was incongruent. In view of the role of the right TPJ in the control of stimulus-driven attention, we argue that these data demonstrate that the processing of nonnumerical magnitudes is more automatic than that of numerical magnitudes and that, therefore, the influence of numerical and nonnumerical variables on each other is asymmetrical.

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