1
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Ye Q, Fidalgo C, Byrne P, Muñoz LE, Cant JS, Lee ACH. Using imagination and the contents of memory to create new scene and object representations: A functional MRI study. Neuropsychologia 2024; 204:109000. [PMID: 39271053 DOI: 10.1016/j.neuropsychologia.2024.109000] [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: 03/20/2024] [Revised: 09/09/2024] [Accepted: 09/10/2024] [Indexed: 09/15/2024]
Abstract
Humans can use the contents of memory to construct scenarios and events that they have not encountered before, a process colloquially known as imagination. Much of our current understanding of the neural mechanisms mediating imagination is limited by paradigms that rely on participants' subjective reports of imagined content. Here, we used a novel behavioral paradigm that was designed to systematically evaluate the contents of an individual's imagination. Participants first learned the layout of four distinct rooms containing five wall segments with differing geometrical characteristics, each associated with a unique object. During functional MRI, participants were then shown two different wall segments or objects on each trial and asked to first, retrieve the associated objects or walls, respectively (retrieval phase) and then second, imagine the two objects side-by-side or combine the two wall segments (imagination phase). Importantly, the contents of each participant's imagination were interrogated by having them make a same/different judgment about the properties of the imagined objects or scenes. Using univariate and multivariate analyses, we observed widespread activity across occipito-temporal cortex for the retrieval of objects and for the imaginative creation of scenes. Interestingly, a classifier, whether trained on the imagination or retrieval data, was able to successfully differentiate the neural patterns associated with the imagination of scenes from that of objects. Our results reveal neural differences in the cued retrieval of object and scene memoranda, demonstrate that different representations underlie the creation and/or imagination of scene and object content, and highlight a novel behavioral paradigm that can be used to systematically evaluate the contents of an individual's imagination.
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Affiliation(s)
- Qun Ye
- Intelligent Laboratory of Child and Adolescent Mental Health and Crisis Intervention of Zhejiang Province, School of Psychology, Zhejiang Normal University, Jinhua, 321004, Zhejiang, China; Key Laboratory of Intelligent Education Technology and Application of Zhejiang Province, Zhejiang Normal University, Jinhua, 321004, Zhejiang, China
| | - Celia Fidalgo
- Department of Psychology (Scarborough), University of Toronto, Toronto, Ontario, M1C 1A4, Canada
| | - Patrick Byrne
- Department of Psychology (Scarborough), University of Toronto, Toronto, Ontario, M1C 1A4, Canada
| | - Luis Eduardo Muñoz
- Department of Psychology (Scarborough), University of Toronto, Toronto, Ontario, M1C 1A4, Canada
| | - Jonathan S Cant
- Department of Psychology (Scarborough), University of Toronto, Toronto, Ontario, M1C 1A4, Canada.
| | - Andy C H Lee
- Department of Psychology (Scarborough), University of Toronto, Toronto, Ontario, M1C 1A4, Canada; Rotman Research Institute, Baycrest Centre, Toronto, Ontario, M6A 2E1, Canada.
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2
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Yashiro R, Sawayama M, Amano K. Decoding time-resolved neural representations of orientation ensemble perception. Front Neurosci 2024; 18:1387393. [PMID: 39148524 PMCID: PMC11325722 DOI: 10.3389/fnins.2024.1387393] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2024] [Accepted: 07/15/2024] [Indexed: 08/17/2024] Open
Abstract
The visual system can compute summary statistics of several visual elements at a glance. Numerous studies have shown that an ensemble of different visual features can be perceived over 50-200 ms; however, the time point at which the visual system forms an accurate ensemble representation associated with an individual's perception remains unclear. This is mainly because most previous studies have not fully addressed time-resolved neural representations that occur during ensemble perception, particularly lacking quantification of the representational strength of ensembles and their correlation with behavior. Here, we conducted orientation ensemble discrimination tasks and electroencephalogram (EEG) recordings to decode orientation representations over time while human observers discriminated an average of multiple orientations. We modeled EEG signals as a linear sum of hypothetical orientation channel responses and inverted this model to quantify the representational strength of orientation ensemble. Our analysis using this inverted encoding model revealed stronger representations of the average orientation over 400-700 ms. We also correlated the orientation representation estimated from EEG signals with the perceived average orientation reported in the ensemble discrimination task with adjustment methods. We found that the estimated orientation at approximately 600-700 ms significantly correlated with the individual differences in perceived average orientation. These results suggest that although ensembles can be quickly and roughly computed, the visual system may gradually compute an orientation ensemble over several hundred milliseconds to achieve a more accurate ensemble representation.
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Affiliation(s)
- Ryuto Yashiro
- Graduate School of Information Science and Technology, The University of Tokyo, Tokyo, Japan
| | - Masataka Sawayama
- Graduate School of Information Science and Technology, The University of Tokyo, Tokyo, Japan
| | - Kaoru Amano
- Graduate School of Information Science and Technology, The University of Tokyo, Tokyo, Japan
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3
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Park J, Soucy E, Segawa J, Mair R, Konkle T. Immersive scene representation in human visual cortex with ultra-wide-angle neuroimaging. Nat Commun 2024; 15:5477. [PMID: 38942766 PMCID: PMC11213904 DOI: 10.1038/s41467-024-49669-0] [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: 09/01/2023] [Accepted: 06/13/2024] [Indexed: 06/30/2024] Open
Abstract
While human vision spans 220°, traditional functional MRI setups display images only up to central 10-15°. Thus, it remains unknown how the brain represents a scene perceived across the full visual field. Here, we introduce a method for ultra-wide angle display and probe signatures of immersive scene representation. An unobstructed view of 175° is achieved by bouncing the projected image off angled-mirrors onto a custom-built curved screen. To avoid perceptual distortion, scenes are created with wide field-of-view from custom virtual environments. We find that immersive scene representation drives medial cortex with far-peripheral preferences, but shows minimal modulation in classic scene regions. Further, scene and face-selective regions maintain their content preferences even with extreme far-periphery stimulation, highlighting that not all far-peripheral information is automatically integrated into scene regions computations. This work provides clarifying evidence on content vs. peripheral preferences in scene representation and opens new avenues to research immersive vision.
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Affiliation(s)
- Jeongho Park
- Department of Psychology, Harvard University, Cambridge, MA, USA.
| | - Edward Soucy
- Center for Brain Science, Harvard University, Cambridge, MA, USA
| | - Jennifer Segawa
- Center for Brain Science, Harvard University, Cambridge, MA, USA
| | - Ross Mair
- Center for Brain Science, Harvard University, Cambridge, MA, USA
- Department of Radiology, Harvard Medical School, Boston, MA, USA
- Department of Radiology, Massachusetts General Hospital, Boston, MA, USA
| | - Talia Konkle
- Department of Psychology, Harvard University, Cambridge, MA, USA
- Center for Brain Science, Harvard University, Cambridge, MA, USA
- Kempner Institute for Biological and Artificial Intelligence, Harvard University, Boston, MA, USA
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4
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Zhu H, Ge Y, Bratch A, Yuille A, Kay K, Kersten D. Natural scenes reveal diverse representations of 2D and 3D body pose in the human brain. Proc Natl Acad Sci U S A 2024; 121:e2317707121. [PMID: 38830105 PMCID: PMC11181088 DOI: 10.1073/pnas.2317707121] [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: 10/19/2023] [Accepted: 04/25/2024] [Indexed: 06/05/2024] Open
Abstract
Human pose, defined as the spatial relationships between body parts, carries instrumental information supporting the understanding of motion and action of a person. A substantial body of previous work has identified cortical areas responsive to images of bodies and different body parts. However, the neural basis underlying the visual perception of body part relationships has received less attention. To broaden our understanding of body perception, we analyzed high-resolution fMRI responses to a wide range of poses from over 4,000 complex natural scenes. Using ground-truth annotations and an application of three-dimensional (3D) pose reconstruction algorithms, we compared similarity patterns of cortical activity with similarity patterns built from human pose models with different levels of depth availability and viewpoint dependency. Targeting the challenge of explaining variance in complex natural image responses with interpretable models, we achieved statistically significant correlations between pose models and cortical activity patterns (though performance levels are substantially lower than the noise ceiling). We found that the 3D view-independent pose model, compared with two-dimensional models, better captures the activation from distinct cortical areas, including the right posterior superior temporal sulcus (pSTS). These areas, together with other pose-selective regions in the LOTC, form a broader, distributed cortical network with greater view-tolerance in more anterior patches. We interpret these findings in light of the computational complexity of natural body images, the wide range of visual tasks supported by pose structures, and possible shared principles for view-invariant processing between articulated objects and ordinary, rigid objects.
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Affiliation(s)
- Hongru Zhu
- Department of Cognitive Science, Johns Hopkins University, Baltimore, MD21218
| | - Yijun Ge
- Department of Psychology, University of Minnesota, Minneapolis, MN55455
- Laboratory for Consciousness, Riken Center for Brain Science, Wako, Saitama3510198, Japan
| | - Alexander Bratch
- Department of Psychology, University of Minnesota, Minneapolis, MN55455
| | - Alan Yuille
- Department of Cognitive Science, Johns Hopkins University, Baltimore, MD21218
| | - Kendrick Kay
- Center for Magnetic Resonance Research, Department of Radiology, University of Minnesota, Minneapolis, MN55455
| | - Daniel Kersten
- Department of Psychology, University of Minnesota, Minneapolis, MN55455
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5
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Knox K, Pratt J, Cant JS. Examining the role of action-driven attention in ensemble processing. J Vis 2024; 24:5. [PMID: 38842835 PMCID: PMC11160948 DOI: 10.1167/jov.24.6.5] [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: 09/20/2023] [Accepted: 04/21/2024] [Indexed: 06/07/2024] Open
Abstract
Ensemble processing allows the visual system to condense visual information into useful summary statistics (e.g., average size), thereby overcoming capacity limitations to visual working memory and attention. To examine the role of attention in ensemble processing, we conducted three experiments using a novel paradigm that merged the action effect (a manipulation of attention) and ensemble processing. Participants were instructed to make a simple action if the feature of a cue word corresponded to a subsequent shape. Immediately after, they were shown an ensemble display of eight ovals of varying sizes and were asked to report either the average size of all ovals or the size of a single oval from the set. In Experiments 1 and 2, participants were cued with a task-relevant feature, and in Experiment 3, participants were cued with a task-irrelevant feature. Overall, the task-relevant cues that elicited an action influenced reports of average size in the ensemble phase more than the cues that were passively viewed, whereas task-irrelevant cues did not bias the reports of average size. The results of this study suggest that attention influences ensemble processing only when it is directed toward a task-relevant feature.
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Affiliation(s)
- Kristina Knox
- Department of Psychology, University of Toronto, Toronto, Canada
- Department of Psychology, University of Toronto Scarborough, Scarborough, Canada
| | - Jay Pratt
- Department of Psychology, University of Toronto, Toronto, Canada
| | - Jonathan S Cant
- Department of Psychology, University of Toronto Scarborough, Scarborough, Canada
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6
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Kozuch B. An embarrassment of richnesses: the PFC isn't the content NCC. Neurosci Conscious 2024; 2024:niae017. [PMID: 38938921 PMCID: PMC11210398 DOI: 10.1093/nc/niae017] [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: 09/07/2023] [Revised: 03/04/2024] [Accepted: 04/26/2024] [Indexed: 06/29/2024] Open
Abstract
Recent years have seen the rise of several theories saying that the prefrontal cortex (PFC) is a neural correlate of visual consciousness (NCC). Especially popular here are theories saying that the PFC is the 'content NCC' for vision, i.e. it contains those brain areas that are not only necessary for consciousness, but also determine 'what' it is that we visually experience (e.g. whether we experience green or red). This article points out how this "upper-deck" form of PFC theory is at odds with the character of visual experience: on the one hand, visual consciousness appears to contain copious amounts of content, with many properties (such as object, shape, or color) being simultaneously represented in many parts of the visual field. On the other hand, the functions that the PFC carries out (e.g. attention and working memory) are each dedicated to processing only a relatively small subset of available visual stimuli. In short, the PFC probably does not produce enough or the right kind of visual representations for it to supply all of the content found in visual experience, in which case the idea that the PFC is the content NCC for vision is probably false. This article also discusses data thought to undercut the idea that visual experience is informationally rich (inattentional blindness, etc.), along with theories of vision according to which "ensemble statistics" are used to represent features in the periphery of the visual field. I'll argue that these lines of evidence fail to close the apparently vast gap between the amount of visual content represented in the visual experience and the amount represented in the PFC.
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Affiliation(s)
- Benjamin Kozuch
- Philosophy Department, University of Alabama, Tuscaloosa, AL 35401, United States
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7
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Park J, Soucy E, Segawa J, Mair R, Konkle T. Immersive scene representation in human visual cortex with ultra-wide angle neuroimaging. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2023.05.14.540275. [PMID: 37292806 PMCID: PMC10245572 DOI: 10.1101/2023.05.14.540275] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
While humans experience the visual environment in a panoramic 220° view, traditional functional MRI setups are limited to display images like postcards in the central 10-15° of the visual field. Thus, it remains unknown how a scene is represented in the brain when perceived across the full visual field. Here, we developed a novel method for ultra-wide angle visual presentation and probed for signatures of immersive scene representation. To accomplish this, we bounced the projected image off angled-mirrors directly onto a custom-built curved screen, creating an unobstructed view of 175°. Scene images were created from custom-built virtual environments with a compatible wide field-of-view to avoid perceptual distortion. We found that immersive scene representation drives medial cortex with far-peripheral preferences, but surprisingly had little effect on classic scene regions. That is, scene regions showed relatively minimal modulation over dramatic changes of visual size. Further, we found that scene and face-selective regions maintain their content preferences even under conditions of central scotoma, when only the extreme far-peripheral visual field is stimulated. These results highlight that not all far-peripheral information is automatically integrated into the computations of scene regions, and that there are routes to high-level visual areas that do not require direct stimulation of the central visual field. Broadly, this work provides new clarifying evidence on content vs. peripheral preferences in scene representation, and opens new neuroimaging research avenues to understand immersive visual representation.
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Affiliation(s)
| | | | | | - Ross Mair
- Center for Brain Science, Harvard University
- Department of Radiology, Harvard Medical School
- Department of Radiology, Massachusetts General Hospital
| | - Talia Konkle
- Department of Psychology, Harvard University
- Center for Brain Science, Harvard University
- Kempner Institute for Biological and Artificial Intelligence, Harvard University
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8
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Sama MA, Nestor A, Cant JS. The Neural Dynamics of Face Ensemble and Central Face Processing. J Neurosci 2024; 44:e1027232023. [PMID: 38148151 PMCID: PMC10869155 DOI: 10.1523/jneurosci.1027-23.2023] [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: 06/09/2023] [Revised: 11/21/2023] [Accepted: 12/11/2023] [Indexed: 12/28/2023] Open
Abstract
Extensive work has investigated the neural processing of single faces, including the role of shape and surface properties. However, much less is known about the neural basis of face ensemble perception (e.g., simultaneously viewing several faces in a crowd). Importantly, the contribution of shape and surface properties have not been elucidated in face ensemble processing. Furthermore, how single central faces are processed within the context of an ensemble remains unclear. Here, we probe the neural dynamics of ensemble representation using pattern analyses as applied to electrophysiology data in healthy adults (seven males, nine females). Our investigation relies on a unique set of stimuli, depicting different facial identities, which vary parametrically and independently along their shape and surface properties. These stimuli were organized into ensemble displays consisting of six surround faces arranged in a circle around one central face. Overall, our results indicate that both shape and surface properties play a significant role in face ensemble encoding, with the latter demonstrating a more pronounced contribution. Importantly, we find that the neural processing of the center face precedes that of the surround faces in an ensemble. Further, the temporal profile of center face decoding is similar to that of single faces, while those of single faces and face ensembles diverge extensively from each other. Thus, our work capitalizes on a new center-surround paradigm to elucidate the neural dynamics of ensemble processing and the information that underpins it. Critically, our results serve to bridge the study of single and ensemble face perception.
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Affiliation(s)
- Marco Agazio Sama
- Department of Psychology, University of Toronto Scarborough, Toronto, Ontario M1C 1A4, Canada
| | - Adrian Nestor
- Department of Psychology, University of Toronto Scarborough, Toronto, Ontario M1C 1A4, Canada
| | - Jonathan Samuel Cant
- Department of Psychology, University of Toronto Scarborough, Toronto, Ontario M1C 1A4, Canada
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9
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Gunia A, Moraresku S, Janča R, Ježdík P, Kalina A, Hammer J, Marusič P, Vlček K. The brain dynamics of visuospatial perspective-taking captured by intracranial EEG. Neuroimage 2024; 285:120487. [PMID: 38072339 DOI: 10.1016/j.neuroimage.2023.120487] [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: 02/05/2023] [Revised: 09/18/2023] [Accepted: 12/05/2023] [Indexed: 12/24/2023] Open
Abstract
Visuospatial perspective-taking (VPT) is the ability to imagine a scene from a position different from the one used in self-perspective judgments (SPJ). We typically use VPT to understand how others see the environment. VPT requires overcoming the self-perspective, and impairments in this process are implicated in various brain disorders, such as schizophrenia and autism. However, the underlying brain areas of VPT are not well distinguished from SPJ-related ones and from domain-general responses to both perspectives. In addition, hierarchical processing theory suggests that domain-specific processes emerge over time from domain-general ones. It mainly focuses on the sensory system, but outside of it, support for this hypothesis is lacking. Therefore, we aimed to spatiotemporally distinguish brain responses domain-specific to VPT from the specific ones to self-perspective, and domain-general responses to both perspectives. In particular, we intended to test whether VPT- and SPJ specific responses begin later than the general ones. We recorded intracranial EEG data from 30 patients with epilepsy who performed a task requiring laterality judgments during VPT and SPJ, and analyzed the spatiotemporal features of responses in the broad gamma band (50-150 Hz). We found VPT-specific processing in a more extensive brain network than SPJ-specific processing. Their dynamics were similar, but both differed from the general responses, which began earlier and lasted longer. Our results anatomically distinguish VPT-specific from SPJ-specific processing. Furthermore, we temporally differentiate between domain-specific and domain-general processes both inside and outside the sensory system, which serves as a novel example of hierarchical processing.
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Affiliation(s)
- Anna Gunia
- Laboratory of Neurophysiology of Memory, Institute of Physiology of the Czech Academy of Sciences, Prague, Czech Republic; Charles University, Third Faculty of Medicine, Prague, Czech Republic.
| | - Sofiia Moraresku
- Laboratory of Neurophysiology of Memory, Institute of Physiology of the Czech Academy of Sciences, Prague, Czech Republic; Charles University, Third Faculty of Medicine, Prague, Czech Republic
| | - Radek Janča
- Department of Circuit Theory, Faculty of Electrical Engineering, Czech Technical University in Prague, Prague, Czech Republic
| | - Petr Ježdík
- Department of Circuit Theory, Faculty of Electrical Engineering, Czech Technical University in Prague, Prague, Czech Republic
| | - Adam Kalina
- Department of Neurology, Second Faculty of Medicine, Charles University, Motol University Hospital, Prague, Czech Republic
| | - Jiří Hammer
- Department of Neurology, Second Faculty of Medicine, Charles University, Motol University Hospital, Prague, Czech Republic
| | - Petr Marusič
- Department of Neurology, Second Faculty of Medicine, Charles University, Motol University Hospital, Prague, Czech Republic
| | - Kamil Vlček
- Laboratory of Neurophysiology of Memory, Institute of Physiology of the Czech Academy of Sciences, Prague, Czech Republic.
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10
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Coggan DD, Tong F. Spikiness and animacy as potential organizing principles of human ventral visual cortex. Cereb Cortex 2023; 33:8194-8217. [PMID: 36958809 PMCID: PMC10321104 DOI: 10.1093/cercor/bhad108] [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: 07/18/2022] [Revised: 03/05/2023] [Accepted: 03/06/2023] [Indexed: 03/25/2023] Open
Abstract
Considerable research has been devoted to understanding the fundamental organizing principles of the ventral visual pathway. A recent study revealed a series of 3-4 topographical maps arranged along the macaque inferotemporal (IT) cortex. The maps articulated a two-dimensional space based on the spikiness and animacy of visual objects, with "inanimate-spiky" and "inanimate-stubby" regions of the maps constituting two previously unidentified cortical networks. The goal of our study was to determine whether a similar functional organization might exist in human IT. To address this question, we presented the same object stimuli and images from "classic" object categories (bodies, faces, houses) to humans while recording fMRI activity at 7 Tesla. Contrasts designed to reveal the spikiness-animacy object space evoked extensive significant activation across human IT. However, unlike the macaque, we did not observe a clear sequence of complete maps, and selectivity for the spikiness-animacy space was deeply and mutually entangled with category-selectivity. Instead, we observed multiple new stimulus preferences in category-selective regions, including functional sub-structure related to object spikiness in scene-selective cortex. Taken together, these findings highlight spikiness as a promising organizing principle of human IT and provide new insights into the role of category-selective regions in visual object processing.
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Affiliation(s)
- David D Coggan
- Department of Psychology, Vanderbilt University, 111 21st Ave S, Nashville, TN 37240, United States
| | - Frank Tong
- Department of Psychology, Vanderbilt University, 111 21st Ave S, Nashville, TN 37240, United States
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11
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Zhao Y, Zeng T, Wang T, Fang F, Pan Y, Jia J. Subcortical encoding of summary statistics in humans. Cognition 2023; 234:105384. [PMID: 36736077 DOI: 10.1016/j.cognition.2023.105384] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2022] [Revised: 01/18/2023] [Accepted: 01/20/2023] [Indexed: 02/04/2023]
Abstract
Statistical encoding compresses redundant information from multiple items into a single summary metric (e.g., mean). Such statistical representation has been suggested to be automatic, but at which stage it is extracted is unknown. Here, we examined the involvement of the subcortex in the processing of summary statistics. We presented an array of circles dichoptically or monocularly while matching the number of perceived circles after binocular fusion. Experiments 1 and 2 showed that interocularly suppressed, invisible circles were automatically involved in the summary statistical representation, but only when they were presented to the same eye as the visible circles. This same-eye effect was further observed for consciously processed circles in Experiment 3, in which the estimated mean size of the circles was biased toward the information transmitted by monocular channels. Together, we provide converging evidence that the processing of summary statistics, an assumed high-level cognitive process, is mediated by subcortical structures.
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Affiliation(s)
- Yuqing Zhao
- Department of Psychology, Hangzhou Normal University, Hangzhou 311121, Zhejiang, China; Center for Cognition and Brain Disorders, The Affiliated Hospital of Hangzhou Normal University, Hangzhou 310015, Zhejiang, China
| | - Ting Zeng
- Center for Cognition and Brain Disorders, The Affiliated Hospital of Hangzhou Normal University, Hangzhou 310015, Zhejiang, China; School of Psychology, Jiangxi Normal University, Nanchang 330022, Jiangxi, China
| | - Tongyu Wang
- Department of Psychology, Hangzhou Normal University, Hangzhou 311121, Zhejiang, China; Center for Cognition and Brain Disorders, The Affiliated Hospital of Hangzhou Normal University, Hangzhou 310015, Zhejiang, China
| | - Fang Fang
- School of Psychological and Cognitive Sciences and Beijing Key Laboratory of Behavior and Mental Health, Peking University, Beijing 100871, China; IDG/McGovern Institute for Brain Research, Peking University, Beijing 100871, China; Peking-Tsinghua Center for Life Sciences, Peking University, Beijing 100871, China
| | - Yi Pan
- Department of Psychology, Hangzhou Normal University, Hangzhou 311121, Zhejiang, China.
| | - Jianrong Jia
- Department of Psychology, Hangzhou Normal University, Hangzhou 311121, Zhejiang, China; Center for Cognition and Brain Disorders, The Affiliated Hospital of Hangzhou Normal University, Hangzhou 310015, Zhejiang, China.
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12
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Ayzenberg V, Behrmann M. Does the brain's ventral visual pathway compute object shape? Trends Cogn Sci 2022; 26:1119-1132. [PMID: 36272937 DOI: 10.1016/j.tics.2022.09.019] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2022] [Revised: 09/22/2022] [Accepted: 09/26/2022] [Indexed: 11/11/2022]
Abstract
A rich behavioral literature has shown that human object recognition is supported by a representation of shape that is tolerant to variations in an object's appearance. Such 'global' shape representations are achieved by describing objects via the spatial arrangement of their local features, or structure, rather than by the appearance of the features themselves. However, accumulating evidence suggests that the ventral visual pathway - the primary substrate underlying object recognition - may not represent global shape. Instead, ventral representations may be better described as a basis set of local image features. We suggest that this evidence forces a reevaluation of the role of the ventral pathway in object perception and posits a broader network for shape perception that encompasses contributions from the dorsal pathway.
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Affiliation(s)
- Vladislav Ayzenberg
- Neuroscience Institute, Carnegie Mellon University, Pittsburgh, PA 15213, USA; Psychology Department, Carnegie Mellon University, Pittsburgh, PA 15213, USA.
| | - Marlene Behrmann
- Neuroscience Institute, Carnegie Mellon University, Pittsburgh, PA 15213, USA; Psychology Department, Carnegie Mellon University, Pittsburgh, PA 15213, USA; The Department of Ophthalmology, University of Pittsburgh, Pittsburgh, PA 15260, USA.
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13
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Ramp-shaped neural tuning supports graded population-level representation of the object-to-scene continuum. Sci Rep 2022; 12:18081. [PMID: 36302932 PMCID: PMC9613906 DOI: 10.1038/s41598-022-21768-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2022] [Accepted: 09/30/2022] [Indexed: 01/24/2023] Open
Abstract
We can easily perceive the spatial scale depicted in a picture, regardless of whether it is a small space (e.g., a close-up view of a chair) or a much larger space (e.g., an entire class room). How does the human visual system encode this continuous dimension? Here, we investigated the underlying neural coding of depicted spatial scale, by examining the voxel tuning and topographic organization of brain responses. We created naturalistic yet carefully-controlled stimuli by constructing virtual indoor environments, and rendered a series of snapshots to smoothly sample between a close-up view of the central object and far-scale view of the full environment (object-to-scene continuum). Human brain responses were measured to each position using functional magnetic resonance imaging. We did not find evidence for a smooth topographic mapping for the object-to-scene continuum on the cortex. Instead, we observed large swaths of cortex with opposing ramp-shaped profiles, with highest responses to one end of the object-to-scene continuum or the other, and a small region showing a weak tuning to intermediate scale views. However, when we considered the population code of the entire ventral occipito-temporal cortex, we found smooth and linear representation of the object-to-scene continuum. Our results together suggest that depicted spatial scale information is encoded parametrically in large-scale population codes across the entire ventral occipito-temporal cortex.
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14
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Jia J, Wang T, Chen S, Ding N, Fang F. Ensemble size perception: Its neural signature and the role of global interaction over individual items. Neuropsychologia 2022; 173:108290. [PMID: 35697088 DOI: 10.1016/j.neuropsychologia.2022.108290] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2021] [Revised: 06/02/2022] [Accepted: 06/07/2022] [Indexed: 10/18/2022]
Abstract
To efficiently process complex visual scenes, the visual system often summarizes statistical information across individual items and represents them as an ensemble. However, due to the lack of techniques to disentangle the representation of the ensemble from that of the individual items constituting the ensemble, whether there exists a specialized neural mechanism for ensemble processing and how ensemble perception is computed in the brain remain unknown. To address these issues, we used a frequency-tagging EEG approach to track brain responses to periodically updated ensemble sizes. Neural responses tracking the ensemble size were detected in parieto-occipital electrodes, revealing a global and specialized neural mechanism of ensemble size perception. We then used the temporal response function to isolate neural responses to the individual sizes and their interactions. Notably, while the individual sizes and their local and global interactions were encoded in the EEG signals, only the global interaction contributed directly to the ensemble size perception. Finally, distributed attention to the global stimulus pattern enhanced the neural signature of the ensemble size, mainly by modulating the neural representation of the global interaction between all individual sizes. These findings advocate a specialized, global neural mechanism of ensemble size perception and suggest that global interaction between individual items contributes to ensemble perception.
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Affiliation(s)
- Jianrong Jia
- Center for Cognition and Brain Disorders, The Affiliated Hospital of Hangzhou Normal University, Hangzhou, 311121, China; Institute of Psychological Sciences, Hangzhou Normal University, Hangzhou, 311121, China
| | - Tongyu Wang
- Center for Cognition and Brain Disorders, The Affiliated Hospital of Hangzhou Normal University, Hangzhou, 311121, China; Institute of Psychological Sciences, Hangzhou Normal University, Hangzhou, 311121, China
| | - Siqi Chen
- Center for Cognition and Brain Disorders, The Affiliated Hospital of Hangzhou Normal University, Hangzhou, 311121, China; Institute of Psychological Sciences, Hangzhou Normal University, Hangzhou, 311121, China
| | - Nai Ding
- Key Laboratory for Biomedical Engineering of Ministry of Education, College of Biomedical Engineering and Instrument Sciences, Zhejiang University, Hangzhou, 311121, China; Research Center for Advanced Artificial Intelligence Theory, Zhejiang Lab, Hangzhou, 311121, China
| | - Fang Fang
- School of Psychological and Cognitive Sciences and Beijing Key Laboratory of Behavior and Mental Health, Peking University, Beijing, 100871, China; IDG/McGovern Institute for Brain Research, Peking University, Beijing, 100871, China; Key Laboratory of Machine Perception (Ministry of Education), Peking University, Beijing, 100871, China; Peking-Tsinghua Center for Life Sciences, Peking University, Beijing, 100871, China.
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15
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Taylor J, Xu Y. Representation of Color, Form, and their Conjunction across the Human Ventral Visual Pathway. Neuroimage 2022; 251:118941. [PMID: 35122966 PMCID: PMC9014861 DOI: 10.1016/j.neuroimage.2022.118941] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2021] [Accepted: 01/25/2022] [Indexed: 11/25/2022] Open
Abstract
Despite decades of research, our understanding of the relationship
between color and form processing in the primate ventral visual pathway remains
incomplete. Using fMRI multivoxel pattern analysis, we examined coding of color
and form, using a simple form feature (orientation) and a mid-level form feature
(curvature), in human ventral visual processing regions. We found that both
color and form could be decoded from activity in early visual areas V1 to V4, as
well as in the posterior color-selective region and shape-selective regions in
ventral and lateral occipitotemporal cortex defined based on their univariate
selectivity to color or shape, respectively (the central color region only
showed color but not form decoding). Meanwhile, decoding biases towards one
feature or the other existed in the color- and shape-selective regions,
consistent with their univariate feature selectivity reported in past studies.
Additional extensive analyses show that while all these regions contain
independent (linearly additive) coding for both features, several early visual
regions also encode the conjunction of color and the simple, but not the
complex, form feature in a nonlinear, interactive manner. Taken together, the
results show that color and form are encoded in a biased distributed and largely
independent manner across ventral visual regions in the human brain.
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Affiliation(s)
- JohnMark Taylor
- Visual Inference Laboratory, Zuckerman Institute, Columbia University.
| | - Yaoda Xu
- Department of Psychology, Yale University
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16
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Three cortical scene systems and their development. Trends Cogn Sci 2022; 26:117-127. [PMID: 34857468 PMCID: PMC8770598 DOI: 10.1016/j.tics.2021.11.002] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2021] [Revised: 10/14/2021] [Accepted: 11/06/2021] [Indexed: 02/03/2023]
Abstract
Since the discovery of three scene-selective regions in the human brain, a central assumption has been that all three regions directly support navigation. We propose instead that cortical scene processing regions support three distinct computational goals (and one not for navigation at all): (i) The parahippocampal place area supports scene categorization, which involves recognizing the kind of place we are in; (ii) the occipital place area supports visually guided navigation, which involves finding our way through the immediately visible environment, avoiding boundaries and obstacles; and (iii) the retrosplenial complex supports map-based navigation, which involves finding our way from a specific place to some distant, out-of-sight place. We further hypothesize that these systems develop along different timelines, with both navigation systems developing slower than the scene categorization system.
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17
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Neural representations of ensemble coding in the occipital and parietal cortices. Neuroimage 2021; 245:118680. [PMID: 34718139 DOI: 10.1016/j.neuroimage.2021.118680] [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] [Received: 08/06/2021] [Revised: 10/17/2021] [Accepted: 10/23/2021] [Indexed: 11/23/2022] Open
Abstract
The human visual system is able to extract summary statistics from sets of similar items, but the underlying neural mechanism remains poorly understood. Using functional magnetic resonance imaging (fMRI) and an encoding model, we examined how the neural representation of ensemble coding is constructed by manipulating the task-relevance of ensemble features. We found a gradual increase in orientation-selective responses to the mean orientation of multiple stimuli along the visual hierarchy only when these orientations were task-relevant. Such responses to the ensemble orientation were present in the extrastriate area, V3, even when the mean orientation was not task-relevant, indicating that the ensemble representation can co-exist with the task-relevant individual feature representation. Ensemble orientations were also represented in frontal regions, but those representations were robust only when each mean orientation was linked to a motor response dimension. Together, our findings suggest that the neural representation of the ensemble percept is formed by pooling signals at multiple levels of the visual processing stream.
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18
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Chaisilprungraung T, Park S. "Scene" from inside: The representation of Observer's space in high-level visual cortex. Neuropsychologia 2021; 161:108010. [PMID: 34454940 DOI: 10.1016/j.neuropsychologia.2021.108010] [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: 04/04/2021] [Revised: 07/30/2021] [Accepted: 08/23/2021] [Indexed: 10/20/2022]
Abstract
Human observers are remarkably adept at perceiving and interacting with visual stimuli around them. Compared to visual stimuli like objects or faces, scenes are unique in that they provide enclosures for observers. An observer looks at a scene by being physically inside the scene. The current research explored this unique observer-scene relationship by studying the neural representation of scenes' spatial boundaries. Previous studies hypothesized that scenes' boundaries were processed in sets of high-level visual cortices. Notably, the parahippocampal place area (PPA), exhibited neural sensitivity to scenes that had closed vs. open spatial boundaries (Kravitz et al., 2011; Park et al., 2011). We asked whether this sensitivity reflected the openness of landscape (e.g., forest vs. beach), or the openness of the environment immediately surrounding the observer (i.e., whether a scene was viewed from inside vs. outside a room). Across two human fMRI experiments, we found that the PPA, as well as another well-known navigation-processing area, the occipital place area (OPA), processed scenes' boundaries according to the observer's space rather than the landscape. Moreover, we found that the PPA's activation pattern was susceptible to manipulations involving mid-level perceptual properties of scenes (e.g., rectilinear pattern of window frames), while the OPA's response was not. Our results have important implications for research in visual scene processing and suggest an important role of an observer's location in representing the spatial boundary, beyond the low-level visual input of a landscape.
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Affiliation(s)
| | - Soojin Park
- Department of Psychology, Yonsei University, Seoul, South Korea.
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19
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Whitwell RL, Striemer CL, Cant JS, Enns JT. The Ties that Bind: Agnosia, Neglect and Selective Attention to Visual Scale. Curr Neurol Neurosci Rep 2021; 21:54. [PMID: 34586544 DOI: 10.1007/s11910-021-01139-6] [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: 07/19/2021] [Indexed: 10/20/2022]
Abstract
PURPOSE OF REVIEW Historical and contemporary treatments of visual agnosia and neglect regard these disorders as largely unrelated. It is thought that damage to different neural processes leads directly to one or the other condition, yet apperceptive variants of agnosia and object-centered variants of neglect share remarkably similar deficits in the quality of conscious experience. Here we argue for a closer association between "apperceptive" variants of visual agnosia and "object-centered" variants of visual neglect. We introduce a theoretical framework for understanding these conditions based on "scale attention", which refers to selecting boundary and surface information at different levels of the structural hierarchy in the visual array. RECENT FINDINGS We review work on visual agnosia, the cortical structures and cortico-cortical pathways that underlie visual perception, visuospatial neglect and object-centered neglect, and attention to scale. We highlight direct and indirect pathways involved in these disorders and in attention to scale. The direct pathway involves the posterior vertical segments of the superior longitudinal fasciculus that are positioned to link the established dorsal and ventral attentional centers in the parietal cortex with structures in the inferior occipitotemporal cortex associated with visual apperceptive agnosia. The connections in the right hemisphere appear to be more important for visual conscious experience, whereas those in the left hemisphere appear to be more strongly associated with the planning and execution of visually guided grasps directed at multi-part objects such as tools. In the latter case, semantic and functional information must drive the selection of the appropriate hand posture and grasp points on the object. This view is supported by studies of grasping in patients with agnosia and in patients with neglect that show that the selection of grasp points when picking up a tool involves both scale attention and semantic contributions from inferotemporal cortex. The indirect pathways, which include the inferior fronto-occipital and horizontal components of the superior longitudinal fasciculi, involve the frontal lobe, working memory and the "multiple demands" network, which can shape the content of visual awareness through the maintenance of goal- and task-based abstractions and their influence on scale attention. Recent studies of human cortico-cortical pathways necessitate revisions to long-standing theoretical views on visual perception, visually guided action and their integrations. We highlight findings from a broad sample of seemingly disparate areas of research to support the proposal that attention to scale is necessary for typical conscious visual experience and for goal-directed actions that depend on functional and semantic information. Furthermore, we suggest that vertical pathways between the parietal and occipitotemporal cortex, along with indirect pathways that involve the premotor and prefrontal cortex, facilitate the operations of scale attention.
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Affiliation(s)
- Robert L Whitwell
- Department of Psychology, University of British Columbia, Vancouver, Canada.
| | | | - Jonathan S Cant
- Department of Psychology, University of Toronto Scarborough, Toronto, Canada
| | - James T Enns
- Department of Psychology, University of British Columbia, Vancouver, Canada
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20
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Tharmaratnam V, Patel M, Lowe MX, Cant JS. Shared cognitive mechanisms involved in the processing of scene texture and scene shape. J Vis 2021; 21:11. [PMID: 34269793 PMCID: PMC8297417 DOI: 10.1167/jov.21.7.11] [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] [Indexed: 12/04/2022] Open
Abstract
Recent research has demonstrated that the parahippocampal place area represents both the shape and texture features of scenes, with the importance of each feature varying according to perceived scene category. Namely, shape features are predominately more diagnostic to the processing of artificial human–made scenes, while shape and texture are equally diagnostic in natural scene processing. However, to date little is known regarding the degree of interactivity or independence observed in the processing of these scene features. Furthermore, manipulating the scope of visual attention (i.e., globally vs. locally) when processing ensembles of multiple objects—stimuli that share a functional neuroanatomical link with scenes—has been shown to affect their cognitive visual representation. It remains unknown whether manipulating the scope of attention impacts scene processing in a similar manner. Using the well-established Garner speeded-classification behavioral paradigm, we investigated the influence of both feature diagnosticity and the scope of visual attention on potential interactivity or independence in the shape and texture processing of artificial human–made scenes. The results revealed asymmetric interference between scene shape and texture processing, with the more diagnostic feature (i.e., shape) interfering with the less diagnostic feature (i.e., texture), but not vice versa. Furthermore, this interference was attenuated and enhanced with more local and global visual processing strategies, respectively. These findings suggest that the scene shape and texture processing are mediated by shared cognitive mechanisms and that, although these representations are governed primarily via feature diagnosticity, they can nevertheless be influenced by the scope of visual attention.
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Affiliation(s)
| | | | - Matthew X Lowe
- Graduate Program in Psychology, University of Toronto, Toronto, ON, Canada.,
| | - Jonathan S Cant
- Graduate Program in Psychology, University of Toronto, Toronto, ON, Canada.,Department of Psychology, University of Toronto Scarborough, Toronto, ON, Canada.,
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21
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Abstract
Perception, representation, and memory of ensemble statistics has attracted growing interest. Studies found that, at different abstraction levels, the brain represents similar items as unified percepts. We found that global ensemble perception is automatic and unconscious, affecting later perceptual judgments regarding individual member items. Implicit effects of set mean and range for low-level feature ensembles (size, orientation, brightness) were replicated for high-level category objects. This similarity suggests that analogous mechanisms underlie these extreme levels of abstraction. Here, we bridge the span between visual features and semantic object categories using the identical implicit perception experimental paradigm for intermediate novel visual-shape categories, constructing ensemble exemplars by introducing systematic variations of a central category base or ancestor. In five experiments, with different item variability, we test automatic representation of ensemble category characteristics and its effect on a subsequent memory task. Results show that observer representation of ensembles includes the group's central shape, category ancestor (progenitor), or group mean. Observers also easily reject memory of shapes belonging to different categories, i.e. originating from different ancestors. We conclude that complex categories, like simple visual form ensembles, are represented in terms of statistics including a central object, as well as category boundaries. We refer to the model proposed by Benna and Fusi (bioRxiv 624239, 2019) that memory representation is compressed when related elements are represented by identifying their ancestor and each one's difference from it. We suggest that ensemble mean perception, like category prototype extraction, might reflect employment at different representation levels of an essential, general representation mechanism.
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Affiliation(s)
- Noam Khayat
- ELSC Edmond & Lily Safra Center for Brain Research and Silberman Life Sciences Institute, Hebrew University, Jerusalem, Israel
| | - Stefano Fusi
- Mortimer B. Zuckerman Mind Brain and Behavior Institute and Department of Neuroscience, Columbia University, New York, NY USA
| | - Shaul Hochstein
- ELSC Edmond & Lily Safra Center for Brain Research and Silberman Life Sciences Institute, Hebrew University, Jerusalem, Israel
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22
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Differential neurodynamics and connectivity in the dorsal and ventral visual pathways during perception of emotional crowds and individuals: a MEG study. COGNITIVE AFFECTIVE & BEHAVIORAL NEUROSCIENCE 2021; 21:776-792. [PMID: 33725334 DOI: 10.3758/s13415-021-00880-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 02/03/2021] [Indexed: 11/08/2022]
Abstract
Reading the prevailing emotion of groups of people ("crowd emotion") is critical to understanding their overall intention and disposition. It alerts us to potential dangers, such as angry mobs or panicked crowds, giving us time to escape. A critical aspect of processing crowd emotion is that it must occur rapidly, because delays often are costly. Although knowing the timing of neural events is crucial for understanding how the brain guides behaviors using coherent signals from a glimpse of multiple faces, this information is currently lacking in the literature on face ensemble coding. Therefore, we used magnetoencephalography to examine the neurodynamics in the dorsal and ventral visual streams and the periamygdaloid cortex to compare perception of groups of faces versus individual faces. Forty-six participants compared two groups of four faces or two individual faces with varying emotional expressions and chose which group or individual they would avoid. We found that the dorsal stream was activated as early as 68 msec after the onset of stimuli containing groups of faces. In contrast, the ventral stream was activated later and predominantly for individual face stimuli. The latencies of the dorsal stream activation peaks correlated with participants' response times for facial crowds. We also found enhanced connectivity earlier between the periamygdaloid cortex and the dorsal stream regions for crowd emotion perception. Our findings suggest that ensemble coding of facial crowds proceeds rapidly and in parallel by engaging the dorsal stream to mediate adaptive social behaviors, via a distinct route from single face perception.
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23
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Markov YA, Tiurina NA. Size-distance rescaling in the ensemble representation of range: Study with binocular and monocular cues. Acta Psychol (Amst) 2021; 213:103238. [PMID: 33387867 DOI: 10.1016/j.actpsy.2020.103238] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2020] [Revised: 10/08/2020] [Accepted: 12/09/2020] [Indexed: 11/15/2022] Open
Abstract
According to numerous studies observers can rapidly and precisely evaluate mean or range of the set. Recent studies have shown that the mean size estimated based on sizes of objects rescaled to their distances (Tiurina & Utochkin, 2019). In the current study, we directly tested this rescaling mechanism on the perception of range using binocular and monocular cues. In Experiment 1, a sample set of circles with different angular sizes and in different apparent distances were stereoscopically presented. Participants had to adjust the range of the test set to match the range of the sample set. The main manipulation was the size-distance correlation for sample and test sets: in negative size-distance correlation, the apparent range had to decrease, while in positive correlation - increase. We found the highest underestimation in the condition with the negative sample correlation and positive test correlation, which could be explained only if ensemble summary statistics were estimated after the item's rescaling. In Experiment 2, we used Ponzo-like illusion and spatial positions as a depth cue. Sets were presented with positive, negative or without size-distance correlation on a grey background or the background with Ponzo-like illusion. We found that the range was underestimated in negative correlation and overestimated in positive correlation. Thus, items of ensemble could be automatically rescaled according to their distance, based on both binocular and monocular cues, and ensemble summary statistics estimation is based on perceived sizes.
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Affiliation(s)
- Yuri A Markov
- National Research University Higher School of Economics, Russia.
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24
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Global and local interference effects in ensemble encoding are best explained by interactions between summary representations of the mean and the range. Atten Percept Psychophys 2021; 83:1106-1128. [PMID: 33506350 PMCID: PMC8049940 DOI: 10.3758/s13414-020-02224-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/30/2020] [Indexed: 11/16/2022]
Abstract
Through ensemble encoding, the visual system compresses redundant statistical properties from multiple items into a single summary metric (e.g., average size). Numerous studies have shown that global summary information is extracted quickly, does not require access to single-item representations, and often interferes with reports of single items from the set. Yet a thorough understanding of ensemble processing would benefit from a more extensive investigation at the local level. Thus, the purpose of this study was to provide a more critical inspection of global-local processing in ensemble perception. Taking inspiration from Navon (Cognitive Psychology, 9(3), 353-383, 1977), we employed a novel paradigm that independently manipulates the degree of interference at the global (mean) or local (single item) level of the ensemble. Initial results were consistent with reciprocal interference between global and local ensemble processing. However, further testing revealed that local interference effects were better explained by interference from another summary statistic, the range of the set. Furthermore, participants were unable to disambiguate single items from the ensemble display from other items that were within the ensemble range but, critically, were not actually present in the ensemble. Thus, it appears that local item values are likely inferred based on their relationship to higher-order summary statistics such as the range and the mean. These results conflict with claims that local information is captured alongside global information in summary representations. In such studies, successful identification of set members was not compared with misidentification of items within the range, but which were nevertheless not presented within the set.
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25
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Herrera-Esposito D, Coen-Cagli R, Gomez-Sena L. Flexible contextual modulation of naturalistic texture perception in peripheral vision. J Vis 2021; 21:1. [PMID: 33393962 PMCID: PMC7794279 DOI: 10.1167/jov.21.1.1] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2020] [Accepted: 12/01/2020] [Indexed: 11/24/2022] Open
Abstract
Peripheral vision comprises most of our visual field, and is essential in guiding visual behavior. Its characteristic capabilities and limitations, which distinguish it from foveal vision, have been explained by the most influential theory of peripheral vision as the product of representing the visual input using summary statistics. Despite its success, this account may provide a limited understanding of peripheral vision, because it neglects processes of perceptual grouping and segmentation. To test this hypothesis, we studied how contextual modulation, namely the modulation of the perception of a stimulus by its surrounds, interacts with segmentation in human peripheral vision. We used naturalistic textures, which are directly related to summary-statistics representations. We show that segmentation cues affect contextual modulation, and that this is not captured by our implementation of the summary-statistics model. We then characterize the effects of different texture statistics on contextual modulation, providing guidance for extending the model, as well as for probing neural mechanisms of peripheral vision.
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Affiliation(s)
- Daniel Herrera-Esposito
- Laboratorio de Neurociencias, Facultad de Ciencias, Universidad de la República, Montevideo, Uruguay
| | - Ruben Coen-Cagli
- Department of Systems and Computational Biology and Dominick P. Purpura Department of Neuroscience, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Leonel Gomez-Sena
- Laboratorio de Neurociencias, Facultad de Ciencias, Universidad de la República, Montevideo, Uruguay
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26
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Schmid AC, Boyaci H, Doerschner K. Dynamic dot displays reveal material motion network in the human brain. Neuroimage 2020; 228:117688. [PMID: 33385563 DOI: 10.1016/j.neuroimage.2020.117688] [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] [Received: 05/20/2020] [Revised: 11/20/2020] [Accepted: 12/19/2020] [Indexed: 11/26/2022] Open
Abstract
There is growing research interest in the neural mechanisms underlying the recognition of material categories and properties. This research field, however, is relatively more recent and limited compared to investigations of the neural mechanisms underlying object and scene category recognition. Motion is particularly important for the perception of non-rigid materials, but the neural basis of non-rigid material motion remains unexplored. Using fMRI, we investigated which brain regions respond preferentially to material motion versus other types of motion. We introduce a new database of stimuli - dynamic dot materials - that are animations of moving dots that induce vivid percepts of various materials in motion, e.g. flapping cloth, liquid waves, wobbling jelly. Control stimuli were scrambled versions of these same animations and rigid three-dimensional rotating dots. Results showed that isolating material motion properties with dynamic dots (in contrast with other kinds of motion) activates a network of cortical regions in both ventral and dorsal visual pathways, including areas normally associated with the processing of surface properties and shape, and extending to somatosensory and premotor cortices. We suggest that such a widespread preference for material motion is due to strong associations between stimulus properties. For example viewing dots moving in a specific pattern not only elicits percepts of material motion; one perceives a flexible, non-rigid shape, identifies the object as a cloth flapping in the wind, infers the object's weight under gravity, and anticipates how it would feel to reach out and touch the material. These results are a first important step in mapping out the cortical architecture and dynamics in material-related motion processing.
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Affiliation(s)
- Alexandra C Schmid
- Department of Psychology, Justus Liebig University Giessen, Giessen 35394, Germany.
| | - Huseyin Boyaci
- Department of Psychology, Justus Liebig University Giessen, Giessen 35394, Germany; Department of Psychology, A.S. Brain Research Center, and National Magnetic Resonance Research Center (UMRAM), Bilkent University, Ankara 06800, Turkey.
| | - Katja Doerschner
- Department of Psychology, Justus Liebig University Giessen, Giessen 35394, Germany; Department of Psychology, A.S. Brain Research Center, and National Magnetic Resonance Research Center (UMRAM), Bilkent University, Ankara 06800, Turkey.
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27
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Josephs EL, Konkle T. Large-scale dissociations between views of objects, scenes, and reachable-scale environments in visual cortex. Proc Natl Acad Sci U S A 2020; 117:29354-29362. [PMID: 33229533 PMCID: PMC7703543 DOI: 10.1073/pnas.1912333117] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Space-related processing recruits a network of brain regions separate from those recruited in object processing. This dissociation has largely been explored by contrasting views of navigable-scale spaces to views of close-up, isolated objects. However, in naturalistic visual experience, we encounter spaces intermediate to these extremes, like the tops of desks and kitchen counters, which are not navigable but typically contain multiple objects. How are such reachable-scale views represented in the brain? In three human functional neuroimaging experiments, we find evidence for a large-scale dissociation of reachable-scale views from both navigable scene views and close-up object views. Three brain regions were identified that showed a systematic response preference to reachable views, located in the posterior collateral sulcus, the inferior parietal sulcus, and superior parietal lobule. Subsequent analyses suggest that these three regions may be especially sensitive to the presence of multiple objects. Further, in all classic scene and object regions, reachable-scale views dissociated from both objects and scenes with an intermediate response magnitude. Taken together, these results establish that reachable-scale environments have a distinct representational signature from both scene and object views in visual cortex.
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Affiliation(s)
- Emilie L Josephs
- Department of Psychology, Harvard University, Cambridge, MA 02138
| | - Talia Konkle
- Department of Psychology, Harvard University, Cambridge, MA 02138
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28
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Car expertise does not compete with face expertise during ensemble coding. Atten Percept Psychophys 2020; 83:1275-1281. [PMID: 33164130 DOI: 10.3758/s13414-020-02188-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/21/2020] [Indexed: 11/08/2022]
Abstract
When objects from two categories of expertise (e.g., faces and cars in dual car/face experts) are processed simultaneously, competition occurs across a variety of tasks. Here, we investigate whether competition between face and car processing also occurs during ensemble coding. The relationship between single object recognition and ensemble coding is debated, but if ensemble coding relies on the same ability as object recognition, we expect cars to interfere with ensemble coding of faces as a function of car expertise. We measured the ability to judge the variability in identity of arrays of faces, in the presence of task-irrelevant distractors (cars or novel objects). On each trial, participants viewed two sequential arrays containing four faces and four distractors, judging which array was the more diverse in terms of face identity. We measured participants' car expertise, object recognition ability, and face recognition ability. Using Bayesian statistics, we found evidence against competition as a function of car expertise during ensemble coding of faces. Face recognition ability predicted ensemble judgments for faces, regardless of the category of task-irrelevant distractors. The result suggests that ensemble coding is not susceptible to competition between different domains of similar expertise, unlike single-object recognition.
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29
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Cant JS, Xu Y. One bad apple spoils the whole bushel: The neural basis of outlier processing. Neuroimage 2020; 211:116629. [PMID: 32057998 PMCID: PMC7942194 DOI: 10.1016/j.neuroimage.2020.116629] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2019] [Revised: 02/01/2020] [Accepted: 02/09/2020] [Indexed: 10/25/2022] Open
Abstract
How are outliers in an otherwise homogeneous object ensemble represented by our visual system? Are outliers ignored because they are the minority? Or do outliers alter our perception of an otherwise homogeneous ensemble? We have previously demonstrated ensemble representation in human anterior-medial ventral visual cortex (overlapping the scene-selective parahippocampal place area; PPA). In this study we investigated how outliers impact object-ensemble representation in this human brain region as well as visual representation throughout posterior brain regions. We presented a homogeneous ensemble followed by an ensemble containing either identical elements or a majority of identical elements with a few outliers. Human participants ignored the outliers and made a same/different judgment between the two ensembles. In PPA, fMRI adaptation was observed when the outliers in the second ensemble matched the items in the first, even though the majority of the elements in the second ensemble were distinct from those in the first; conversely, release from fMRI adaptation was observed when the outliers in the second ensemble were distinct from the items in the first, even though the majority of the elements in the second ensemble were identical to those in the first. A similarly robust outlier effect was also found in other brain regions, including a shape-processing region in lateral occipital cortex (LO) and task-processing fronto-parietal regions. These brain regions likely work in concert to flag the presence of outliers during visual perception and then weigh the outliers appropriately in subsequent behavioral decisions. To our knowledge, this is the first time the neural mechanisms involved in outlier processing have been systematically documented in the human brain. Such an outlier effect could well provide the neural basis mediating our perceptual experience in situations like "one bad apple spoils the whole bushel".
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Affiliation(s)
- Jonathan S Cant
- Department of Psychology, University of Toronto Scarborough, Toronto, ON, M1C 1A4, Canada.
| | - Yaoda Xu
- Department of Psychology, Yale University, New Haven, CT, 06477, USA
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30
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Coding of Navigational Distance and Functional Constraint of Boundaries in the Human Scene-Selective Cortex. J Neurosci 2020; 40:3621-3630. [PMID: 32209608 DOI: 10.1523/jneurosci.1991-19.2020] [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] [Received: 08/12/2019] [Revised: 02/28/2020] [Accepted: 03/05/2020] [Indexed: 11/21/2022] Open
Abstract
For visually guided navigation, the use of environmental cues is essential. Particularly, detecting local boundaries that impose limits to locomotion and estimating their location is crucial. In a series of three fMRI experiments, we investigated whether there is a neural coding of navigational distance in the human visual cortex (both female and male). We used virtual reality software to systematically manipulate the distance from a viewer perspective to different types of a boundary. Using a multivoxel pattern classification employing a linear support vector machine, we found that the occipital place area (OPA) is sensitive to the navigational distance restricted by the transparent glass wall. Further, the OPA was sensitive to a non-crossable boundary only, suggesting an importance of the functional constraint of a boundary. Together, we propose the OPA as a perceptual source of external environmental features relevant for navigation.SIGNIFICANCE STATEMENT One of major goals in cognitive neuroscience has been to understand the nature of visual scene representation in human ventral visual cortex. An aspect of scene perception that has been overlooked despite its ecological importance is the analysis of space for navigation. One of critical computation necessary for navigation is coding of distance to environmental boundaries that impose limit on navigator's movements. This paper reports the first empirical evidence for coding of navigational distance in the human visual cortex and its striking sensitivity to functional constraint of environmental boundaries. Such finding links the paper to previous neurological and behavioral works that emphasized the distance to boundaries as a crucial geometric property for reorientation behavior of children and other animal species.
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31
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Khvostov VA, Utochkin IS. Independent and parallel visual processing of ensemble statistics: Evidence from dual tasks. J Vis 2020; 19:3. [PMID: 31390466 DOI: 10.1167/19.9.3] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
The visual system can represent multiple objects in a compressed form of ensemble summary statistics (such as object numerosity, mean, and feature variance/range). Yet the relationships between the different types of visual statistics remain relatively unclear. Here, we tested whether two summaries (mean and numerosity, or mean and range) are calculated independently from each other and in parallel. Our participants performed dual tasks requiring a report about two summaries in each trial, and single tasks requiring a report about one of the summaries. We estimated trial-by-trial correlations between the precision of reports as well as correlations across observers. Both analyses showed the absence of correlations between different types of ensemble statistics, suggesting their independence. We also found no decrement (except that related to the order of report explained by memory retrieval) in performance in dual compared to single tasks, which suggests that two statistics of one ensemble can be processed in parallel.
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Affiliation(s)
- Vladislav A Khvostov
- National Research University Higher School of Economics, Moscow, Russian Federation
| | - Igor S Utochkin
- National Research University Higher School of Economics, Moscow, Russian Federation
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32
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Schwettmann S, Tenenbaum JB, Kanwisher N. Invariant representations of mass in the human brain. eLife 2019; 8:46619. [PMID: 31845887 PMCID: PMC7007217 DOI: 10.7554/elife.46619] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2019] [Accepted: 12/10/2019] [Indexed: 01/14/2023] Open
Abstract
An intuitive understanding of physical objects and events is critical for successfully interacting with the world. Does the brain achieve this understanding by running simulations in a mental physics engine, which represents variables such as force and mass, or by analyzing patterns of motion without encoding underlying physical quantities? To investigate, we scanned participants with fMRI while they viewed videos of objects interacting in scenarios indicating their mass. Decoding analyses in brain regions previously implicated in intuitive physical inference revealed mass representations that generalized across variations in scenario, material, friction, and motion energy. These invariant representations were found during tasks without action planning, and tasks focusing on an orthogonal dimension (object color). Our results support an account of physical reasoning where abstract physical variables serve as inputs to a forward model of dynamics, akin to a physics engine, in parietal and frontal cortex.
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Affiliation(s)
- Sarah Schwettmann
- Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, United States.,Center for Brains, Minds, and Machines, Massachusetts Institute of Technology, Cambridge, United States.,McGovern Institute for Brain Research, Massachusetts Institute of Technology, Cambridge, United States
| | - Joshua B Tenenbaum
- Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, United States.,Center for Brains, Minds, and Machines, Massachusetts Institute of Technology, Cambridge, United States.,McGovern Institute for Brain Research, Massachusetts Institute of Technology, Cambridge, United States.,Computer Science and Artificial Intelligence Laboratory, Massachusetts Institute of Technology, Cambridge, United States
| | - Nancy Kanwisher
- Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, United States.,Center for Brains, Minds, and Machines, Massachusetts Institute of Technology, Cambridge, United States.,McGovern Institute for Brain Research, Massachusetts Institute of Technology, Cambridge, United States
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33
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34
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Julian JB, Keinath AT, Marchette SA, Epstein RA. The Neurocognitive Basis of Spatial Reorientation. Curr Biol 2019; 28:R1059-R1073. [PMID: 30205055 DOI: 10.1016/j.cub.2018.04.057] [Citation(s) in RCA: 50] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
The ability to recover one's bearings when lost is a skill that is fundamental for spatial navigation. We review the cognitive and neural mechanisms that underlie this ability, with the aim of linking together previously disparate findings from animal behavior, human psychology, electrophysiology, and cognitive neuroscience. Behavioral work suggests that reorientation involves two key abilities: first, the recovery of a spatial reference frame (a cognitive map) that is appropriate to the current environment; and second, the determination of one's heading and location relative to that reference frame. Electrophysiological recording studies, primarily in rodents, have revealed potential correlates of these operations in place, grid, border/boundary, and head-direction cells in the hippocampal formation. Cognitive neuroscience studies, primarily in humans, suggest that the perceptual inputs necessary for these operations are processed by neocortical regions such as the retrosplenial complex, occipital place area and parahippocampal place area, with the retrosplenial complex mediating spatial transformations between the local environment and the recovered spatial reference frame, the occipital place area supporting perception of local boundaries, and the parahippocampal place area processing visual information that is essential for identification of the local spatial context. By combining results across these various literatures, we converge on a unified account of reorientation that bridges the cognitive and neural domains.
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Affiliation(s)
- Joshua B Julian
- University of Pennsylvania, Department of Psychology, 3710 Hamilton Walk, Philadelphia, PA 19104, USA; Kavli Institute for Systems Neuroscience, Centre for Neural Computation, NTNU, Norwegian University of Science and Technology, Trondheim, Norway.
| | - Alexandra T Keinath
- University of Pennsylvania, Department of Psychology, 3710 Hamilton Walk, Philadelphia, PA 19104, USA; McGill University, Douglas Mental Health University Institute, 6875 Boulevard LaSalle, Verdun, QC, Canada
| | - Steven A Marchette
- University of Pennsylvania, Department of Psychology, 3710 Hamilton Walk, Philadelphia, PA 19104, USA
| | - Russell A Epstein
- University of Pennsylvania, Department of Psychology, 3710 Hamilton Walk, Philadelphia, PA 19104, USA.
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35
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Elucidating the Neural Representation and the Processing Dynamics of Face Ensembles. J Neurosci 2019; 39:7737-7747. [PMID: 31413074 DOI: 10.1523/jneurosci.0471-19.2019] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2019] [Revised: 08/02/2019] [Accepted: 08/06/2019] [Indexed: 11/21/2022] Open
Abstract
Extensive behavioral work has documented the ability of the human visual system to extract summary representations from face ensembles (e.g., the average identity of a crowd of faces). Yet, the nature of such representations, their underlying neural mechanisms, and their temporal dynamics await elucidation. Here, we examine summary representations of facial identity in human adults (of both sexes) with the aid of pattern analyses, as applied to EEG data, along with behavioral testing. Our findings confirm the ability of the visual system to form such representations both explicitly and implicitly (i.e., with or without the use of specific instructions). We show that summary representations, rather than individual ensemble constituents, can be decoded from neural signals elicited by ensemble perception, we describe the properties of such representations by appeal to multidimensional face space constructs, and we visualize their content through neural-based image reconstruction. Further, we show that the temporal profile of ensemble processing diverges systematically from that of single faces consistent with a slower, more gradual accumulation of perceptual information. Thus, our findings reveal the representational basis of ensemble processing, its fine-grained visual content, and its neural dynamics.SIGNIFICANCE STATEMENT Humans encounter groups of faces, or ensembles, in a variety of environments. Previous behavioral research has investigated how humans process face ensembles as well as the types of summary representations that can be derived from them, such as average emotion, gender, and identity. However, the neural mechanisms mediating these processes are unclear. Here, we demonstrate that ensemble representations, with different facial identity summaries, can be decoded and even visualized from neural data through multivariate analyses. These results provide, to our knowledge, the first detailed investigation into the status and the visual content of neural ensemble representations of faces. Further, the current findings shed light on the temporal dynamics of face ensembles and its relationship with single-face processing.
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36
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Castaldi E, Piazza M, Dehaene S, Vignaud A, Eger E. Attentional amplification of neural codes for number independent of other quantities along the dorsal visual stream. eLife 2019; 8:45160. [PMID: 31339490 PMCID: PMC6693892 DOI: 10.7554/elife.45160] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2019] [Accepted: 07/18/2019] [Indexed: 01/29/2023] Open
Abstract
Humans and other animals base important decisions on estimates of number, and intraparietal cortex is thought to provide a crucial substrate of this ability. However, it remains debated whether an independent neuronal processing mechanism underlies this ‘number sense’, or whether number is instead judged indirectly on the basis of other quantitative features. We performed high-resolution 7 Tesla fMRI while adult human volunteers attended either to the numerosity or an orthogonal dimension (average item size) of visual dot arrays. Along the dorsal visual stream, numerosity explained a significant amount of variance in activation patterns, above and beyond non-numerical dimensions. Its representation was selectively amplified and progressively enhanced across the hierarchy when task relevant. Our results reveal a sensory extraction mechanism yielding information on numerosity separable from other dimensions already at early visual stages and suggest that later regions along the dorsal stream are most important for explicit manipulation of numerical quantity. Numbers and the ability to count and calculate are an essential part of human culture. They are part of everyday life, featuring in calendars, computers or the weekly shop, but also in some of humanity’s biggest achievements: without them the pyramids or space travel would not exist. A precursor of sophisticated mathematical skill could reside in a simpler mental ability: the capacity to assess numerical quantities at a glance. This ‘number sense’ appears in humans in early childhood and it is also present in other animals, but it is still poorly understood. Brain imaging techniques have identified the parts of the brain that are active when perceiving numbers or making calculations. As techniques have advanced, it has become possible to resolve fine differences in brain activity that occur when people switch their attention between different visual tasks. But how exactly does the human brain process visual information to make sense of numbers? One theory suggests that humans use visual cues, such as the size of a group of objects or how densely packed objects are, to estimate numbers. On the other hand, it is also possible that humans can sense number directly, without reference to other properties of the group being observed. Castaldi et al. presented twenty adult volunteers with groups of dots and asked them to focus either on the number of dots or on the size of the dots during a brain scan. This approach allowed the separation of brain signals specific to number from signals corresponding to other visual cues, such as size or density of the group. The experiment revealed that brain activity changed depending on the number of dots displayed. The signal related to number became stronger when people focused on the number of dots, while signals related to other properties of the group remained unchanged. Moreover, brain signals for number were observed at the very early stages of visual processing, in the parts of the brain that receive input from the eyes first. These results suggest that the human visual system perceives number directly, and not by processing information about the size or density of a group of objects. This finding provides insights into how human brains encode numbers, which could be important to understand disorders where number sense can be impaired leading to difficulties learning math and operating with numbers.
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Affiliation(s)
- Elisa Castaldi
- Cognitive Neuroimaging Unit, CEA DRF/JOLIOT, INSERM, Université Paris-Sud, Université Paris-Saclay, NeuroSpin Center, Gif-sur-Yvette, France
| | - Manuela Piazza
- Center for Mind/Brain Sciences, University of Trento, Trento, Italy
| | - Stanislas Dehaene
- Cognitive Neuroimaging Unit, CEA DRF/JOLIOT, INSERM, Université Paris-Sud, Université Paris-Saclay, NeuroSpin Center, Gif-sur-Yvette, France
| | - Alexandre Vignaud
- UNIRS, CEA DRF/JOLIOT, Université Paris-Saclay, NeuroSpin Center, Gif-sur-Yvette, France
| | - Evelyn Eger
- Cognitive Neuroimaging Unit, CEA DRF/JOLIOT, INSERM, Université Paris-Sud, Université Paris-Saclay, NeuroSpin Center, Gif-sur-Yvette, France
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37
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Abstract
Humans are remarkably adept at perceiving and understanding complex real-world scenes. Uncovering the neural basis of this ability is an important goal of vision science. Neuroimaging studies have identified three cortical regions that respond selectively to scenes: parahippocampal place area, retrosplenial complex/medial place area, and occipital place area. Here, we review what is known about the visual and functional properties of these brain areas. Scene-selective regions exhibit retinotopic properties and sensitivity to low-level visual features that are characteristic of scenes. They also mediate higher-level representations of layout, objects, and surface properties that allow individual scenes to be recognized and their spatial structure ascertained. Challenges for the future include developing computational models of information processing in scene regions, investigating how these regions support scene perception under ecologically realistic conditions, and understanding how they operate in the context of larger brain networks.
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Affiliation(s)
- Russell A Epstein
- Department of Psychology, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA;
| | - Chris I Baker
- Section on Learning and Plasticity, Laboratory of Brain and Cognition, National Institute of Mental Health, Bethesda, Maryland 20892, USA;
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38
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Henriksson L, Mur M, Kriegeskorte N. Rapid Invariant Encoding of Scene Layout in Human OPA. Neuron 2019; 103:161-171.e3. [PMID: 31097360 DOI: 10.1016/j.neuron.2019.04.014] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2018] [Revised: 03/13/2019] [Accepted: 04/05/2019] [Indexed: 01/30/2023]
Abstract
Successful visual navigation requires a sense of the geometry of the local environment. How do our brains extract this information from retinal images? Here we visually presented scenes with all possible combinations of five scene-bounding elements (left, right, and back walls; ceiling; floor) to human subjects during functional magnetic resonance imaging (fMRI) and magnetoencephalography (MEG). The fMRI response patterns in the scene-responsive occipital place area (OPA) reflected scene layout with invariance to changes in surface texture. This result contrasted sharply with the primary visual cortex (V1), which reflected low-level image features of the stimuli, and the parahippocampal place area (PPA), which showed better texture than layout decoding. MEG indicated that the texture-invariant scene layout representation is computed from visual input within ∼100 ms, suggesting a rapid computational mechanism. Taken together, these results suggest that the cortical representation underlying our instant sense of the environmental geometry is located in the OPA.
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Affiliation(s)
- Linda Henriksson
- Department of Neuroscience and Biomedical Engineering, Aalto University, 02150 Espoo, Finland; AMI Centre, MEG Core, ABL, Aalto NeuroImaging, Aalto University, 02150 Espoo, Finland.
| | - Marieke Mur
- MRC Cognition and Brain Sciences Unit, University of Cambridge, Cambridge CB2 7EF, UK; Department of Psychology, Brain and Mind Institute, Western University, London, ON N6A 3K7, Canada
| | - Nikolaus Kriegeskorte
- MRC Cognition and Brain Sciences Unit, University of Cambridge, Cambridge CB2 7EF, UK; Department of Psychology, Department of Neuroscience, and Department of Electrical Engineering, Zuckerman Mind Brain Behavior Institute, Columbia University, New York, NY 10032, USA
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39
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Sama MA, Nestor A, Cant JS. Independence of viewpoint and identity in face ensemble processing. J Vis 2019; 19:2. [DOI: 10.1167/19.5.2] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Affiliation(s)
- Marco A. Sama
- Department of Psychology, University of Toronto Scarborough, Toronto, Canada
| | - Adrian Nestor
- Department of Psychology, University of Toronto Scarborough, Toronto, Canada
| | - Jonathan S. Cant
- Department of Psychology, University of Toronto Scarborough, Toronto, Canada
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40
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Abstract
The visual system represents summary statistical information from a set of similar items, a phenomenon known as ensemble perception. In exploring various ensemble domains (e.g., orientation, color, facial expression), researchers have often employed the method of continuous report, in which observers select their responses from a gradually changing morph sequence. However, given their current implementation, some face morphs unintentionally introduce noise into the ensemble measurement. Specifically, some facial expressions on the morph wheel appear perceptually similar even though they are far apart in stimulus space. For instance, in a morph wheel of happy-sad-angry-happy expressions, an expression between happy and sad may not be discriminable from an expression between sad and angry. Without accounting for this confusability, observer ability will be underestimated. In the present experiments we accounted for this by delineating the perceptual confusability of morphs of multiple expressions. In a two-alternative forced choice task, eight observers were asked to discriminate between anchor images (36 in total) and all 360 facial expressions on the morph wheel. The results were visualized on a "confusability matrix," depicting the morphs most likely to be confused for one another. The matrix revealed multiple confusable images between distant expressions on the morph wheel. By accounting for these "confusability regions," we demonstrated a significant improvement in performance estimation on a set of independent ensemble data, suggesting that high-level ensemble abilities may be better than has been previously thought. We also provide an alternative computational approach that may be used to determine potentially confusable stimuli in a given morph space.
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41
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Greene MR. The information content of scene categories. PSYCHOLOGY OF LEARNING AND MOTIVATION 2019. [DOI: 10.1016/bs.plm.2019.03.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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42
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Groen IIA, Jahfari S, Seijdel N, Ghebreab S, Lamme VAF, Scholte HS. Scene complexity modulates degree of feedback activity during object detection in natural scenes. PLoS Comput Biol 2018; 14:e1006690. [PMID: 30596644 PMCID: PMC6329519 DOI: 10.1371/journal.pcbi.1006690] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2018] [Revised: 01/11/2019] [Accepted: 12/01/2018] [Indexed: 02/06/2023] Open
Abstract
Selective brain responses to objects arise within a few hundreds of milliseconds of neural processing, suggesting that visual object recognition is mediated by rapid feed-forward activations. Yet disruption of neural responses in early visual cortex beyond feed-forward processing stages affects object recognition performance. Here, we unite these discrepant findings by reporting that object recognition involves enhanced feedback activity (recurrent processing within early visual cortex) when target objects are embedded in natural scenes that are characterized by high complexity. Human participants performed an animal target detection task on natural scenes with low, medium or high complexity as determined by a computational model of low-level contrast statistics. Three converging lines of evidence indicate that feedback was selectively enhanced for high complexity scenes. First, functional magnetic resonance imaging (fMRI) activity in early visual cortex (V1) was enhanced for target objects in scenes with high, but not low or medium complexity. Second, event-related potentials (ERPs) evoked by target objects were selectively enhanced at feedback stages of visual processing (from ~220 ms onwards) for high complexity scenes only. Third, behavioral performance for high complexity scenes deteriorated when participants were pressed for time and thus less able to incorporate the feedback activity. Modeling of the reaction time distributions using drift diffusion revealed that object information accumulated more slowly for high complexity scenes, with evidence accumulation being coupled to trial-to-trial variation in the EEG feedback response. Together, these results suggest that while feed-forward activity may suffice to recognize isolated objects, the brain employs recurrent processing more adaptively in naturalistic settings, using minimal feedback for simple scenes and increasing feedback for complex scenes.
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Affiliation(s)
- Iris I. A. Groen
- New York University, Department of Psychology, New York, New York, United States of America
| | - Sara Jahfari
- Spinoza Centre for Neuroimaging, Royal Netherlands Academy of Arts and Sciences (KNAW), Amsterdam, The Netherlands
- University of Amsterdam, Department of Psychology, Section Brain and Cognition, Amsterdam, The Netherlands
| | - Noor Seijdel
- University of Amsterdam, Department of Psychology, Section Brain and Cognition, Amsterdam, The Netherlands
| | - Sennay Ghebreab
- University of Amsterdam, Department of Psychology, Section Brain and Cognition, Amsterdam, The Netherlands
- University of Amsterdam, Department of Informatics, Intelligent Systems Lab, Amsterdam, The Netherlands
| | - Victor A. F. Lamme
- University of Amsterdam, Department of Psychology, Section Brain and Cognition, Amsterdam, The Netherlands
| | - H. Steven Scholte
- University of Amsterdam, Department of Psychology, Section Brain and Cognition, Amsterdam, The Netherlands
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43
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Neural Mechanisms of Material Perception: Quest on Shitsukan. Neuroscience 2018; 392:329-347. [PMID: 30213767 DOI: 10.1016/j.neuroscience.2018.09.001] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2018] [Revised: 08/13/2018] [Accepted: 09/03/2018] [Indexed: 01/11/2023]
Abstract
In recent years, a growing body of research has addressed the nature and mechanism of material perception. Material perception entails perceiving and recognizing a material, surface quality or internal state of an object based on sensory stimuli such as visual, tactile, and/or auditory sensations. This process is ongoing in every aspect of daily life. We can, for example, easily distinguish whether an object is made of wood or metal, or whether a surface is rough or smooth. Judging whether the ground is wet or dry or whether a fish is fresh also involves material perception. Information obtained through material perception can be used to govern actions toward objects and to make decisions about whether to approach an object or avoid it. Because the physical processes leading to sensory signals related to material perception is complicated, it has been difficult to manipulate experimental stimuli in a rigorous manner. However, that situation is now changing thanks to advances in technology and knowledge in related fields. In this article, we will review what is currently known about the neural mechanisms responsible for material perception. We will show that cortical areas in the ventral visual pathway are strongly involved in material perception. Our main focus is on vision, but every sensory modality is involved in material perception. Information obtained through different sensory modalities is closely linked in material perception. Such cross-modal processing is another important feature of material perception, and will also be covered in this review.
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44
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Relating the perception of visual ensemble statistics to individual levels of autistic traits. Atten Percept Psychophys 2018; 80:1667-1674. [PMID: 30088256 DOI: 10.3758/s13414-018-1580-1] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Integrating information across the visual field into an ensemble (e.g., seeing the forest from the trees) is an effective strategy to efficiently process the visual world, and one that is often impaired in autism spectrum disorder. Individual differences in sensory processing predict ensemble encoding, providing a potential mechanism for differing perceptual strategies across individuals, and possibly across diagnostic groups exhibiting atypical sensory processing. Here, we explore whether ensemble encoding is associated with traits associated with autism spectrum disorder (ASD). Participants (N=68) were presented with an ensemble display consisting of circles of varying sizes and colors, and were asked to remember the size of the red and blue circles, while ignoring the green circles. Participants were then cued to a target location after a brief delay, and instructed to report the remembered size of the circle they had previously viewed in that location, as ensemble information commonly biases memory for individual objects toward the probed mean of a set of similar objects. The Autism-spectrum Quotient (AQ) was completed to measure each individual's level of autistic traits. We found that an individual's level of ensemble perception, measured as their bias toward the probed mean, was negatively associated with a higher level of ASD traits. These results suggest that individuals with higher levels of ASD traits are less likely to integrate perceptual information. These findings may shed light on different perceptual processing within the autism spectrum, and provide insight into the relationship between individual differences and ensemble encoding.
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45
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Utochkin IS, Khvostov VA, Stakina YM. Continuous to discrete: Ensemble-based segmentation in the perception of multiple feature conjunctions. Cognition 2018; 179:178-191. [PMID: 29960219 DOI: 10.1016/j.cognition.2018.06.016] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2017] [Revised: 06/18/2018] [Accepted: 06/23/2018] [Indexed: 11/29/2022]
Abstract
Although objects around us vary in a number of continuous dimensions (color, size, orientation, etc.), we tend to perceive the objects using more discrete, categorical descriptions (e.g., berries and leaves). Previously, we described how continuous ensemble statistics of simple features are transformed into categorical classes: The visual system tests whether the feature distribution has one or several peaks, each representing a likely "category". Here, we tested the mechanism of segmentation for more complex conjunctions of features. Observers discriminated between two textures filled with lines of various lengths and orientations, which had same distributions between the textures, but opposite directions of correlations. Critically, feature distributions could be "segmentable" (only extreme feature values and a large gap between them) or "non-segmentable" (both extreme and middle values with smooth transition are present). Segmentable displays yielded steeper psychometric functions indicating better discrimination (Experiment 1). The effect of segmentability arises early in visual processing (Experiment 2) and is likely to be provided by global sampling of the entire field (Experiment 3). Also, rapid segmentation requires both feature dimensions having a "segmentable" distribution supporting division of the textures into categorical classes of conjunctions. We propose that observers select items from one side (peak) of one dimension and sample mean differences along a second dimension within the selected subset. In this scenario, subset selection is a limiting factor (Experiment 4) of texture discrimination. Yet, segmentability provided by the sharp feature distributions seems to facilitate both subset selection and mean comparison.
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Affiliation(s)
- Igor S Utochkin
- National Research University Higher School of Economics, Russian Federation.
| | | | - Yulia M Stakina
- National Research University Higher School of Economics, Russian Federation
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46
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Bonner MF, Epstein RA. Computational mechanisms underlying cortical responses to the affordance properties of visual scenes. PLoS Comput Biol 2018; 14:e1006111. [PMID: 29684011 PMCID: PMC5933806 DOI: 10.1371/journal.pcbi.1006111] [Citation(s) in RCA: 52] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2017] [Revised: 05/03/2018] [Accepted: 03/31/2018] [Indexed: 11/24/2022] Open
Abstract
Biologically inspired deep convolutional neural networks (CNNs), trained for computer vision tasks, have been found to predict cortical responses with remarkable accuracy. However, the internal operations of these models remain poorly understood, and the factors that account for their success are unknown. Here we develop a set of techniques for using CNNs to gain insights into the computational mechanisms underlying cortical responses. We focused on responses in the occipital place area (OPA), a scene-selective region of dorsal occipitoparietal cortex. In a previous study, we showed that fMRI activation patterns in the OPA contain information about the navigational affordances of scenes; that is, information about where one can and cannot move within the immediate environment. We hypothesized that this affordance information could be extracted using a set of purely feedforward computations. To test this idea, we examined a deep CNN with a feedforward architecture that had been previously trained for scene classification. We found that responses in the CNN to scene images were highly predictive of fMRI responses in the OPA. Moreover the CNN accounted for the portion of OPA variance relating to the navigational affordances of scenes. The CNN could thus serve as an image-computable candidate model of affordance-related responses in the OPA. We then ran a series of in silico experiments on this model to gain insights into its internal operations. These analyses showed that the computation of affordance-related features relied heavily on visual information at high-spatial frequencies and cardinal orientations, both of which have previously been identified as low-level stimulus preferences of scene-selective visual cortex. These computations also exhibited a strong preference for information in the lower visual field, which is consistent with known retinotopic biases in the OPA. Visualizations of feature selectivity within the CNN suggested that affordance-based responses encoded features that define the layout of the spatial environment, such as boundary-defining junctions and large extended surfaces. Together, these results map the sensory functions of the OPA onto a fully quantitative model that provides insights into its visual computations. More broadly, they advance integrative techniques for understanding visual cortex across multiple level of analysis: from the identification of cortical sensory functions to the modeling of their underlying algorithms. How does visual cortex compute behaviorally relevant properties of the local environment from sensory inputs? For decades, computational models have been able to explain only the earliest stages of biological vision, but recent advances in deep neural networks have yielded a breakthrough in the modeling of high-level visual cortex. However, these models are not explicitly designed for testing neurobiological theories, and, like the brain itself, their internal operations remain poorly understood. We examined a deep neural network for insights into the cortical representation of navigational affordances in visual scenes. In doing so, we developed a set of high-throughput techniques and statistical tools that are broadly useful for relating the internal operations of neural networks with the information processes of the brain. Our findings demonstrate that a deep neural network with purely feedforward computations can account for the processing of navigational layout in high-level visual cortex. We next performed a series of experiments and visualization analyses on this neural network. These analyses characterized a set of stimulus input features that may be critical for computing navigationally related cortical representations, and they identified a set of high-level, complex scene features that may serve as a basis set for the cortical coding of navigational layout. These findings suggest a computational mechanism through which high-level visual cortex might encode the spatial structure of the local navigational environment, and they demonstrate an experimental approach for leveraging the power of deep neural networks to understand the visual computations of the brain.
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Affiliation(s)
- Michael F. Bonner
- Department of Psychology, University of Pennsylvania, Philadelphia, PA, United States of America
- * E-mail:
| | - Russell A. Epstein
- Department of Psychology, University of Pennsylvania, Philadelphia, PA, United States of America
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Wang S, Cao L, Xu J, Zhang G, Lou Y, Liu B. Revealing the Semantic Association between Perception of Scenes and Significant Objects by Representational Similarity Analysis. Neuroscience 2018; 372:87-96. [DOI: 10.1016/j.neuroscience.2017.12.043] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2017] [Revised: 12/19/2017] [Accepted: 12/23/2017] [Indexed: 11/29/2022]
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Julian JB, Ryan J, Hamilton RH, Epstein RA. The Occipital Place Area Is Causally Involved in Representing Environmental Boundaries during Navigation. Curr Biol 2018; 26:1104-9. [PMID: 27020742 DOI: 10.1016/j.cub.2016.02.066] [Citation(s) in RCA: 82] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2016] [Revised: 02/24/2016] [Accepted: 02/26/2016] [Indexed: 10/21/2022]
Abstract
Thirty years of research suggests that environmental boundaries-e.g., the walls of an experimental chamber or room-exert powerful influence on navigational behavior, often to the exclusion of other cues [1-9]. Consistent with this behavioral work, neurons in brain structures that instantiate spatial memory often exhibit firing fields that are strongly controlled by environmental boundaries [10-15]. Despite the clear importance of environmental boundaries for spatial coding, however, a brain region that mediates the perception of boundary information has not yet been identified. We hypothesized that the occipital place area (OPA), a scene-selective region located near the transverse occipital sulcus [16], might provide this perceptual source by extracting boundary information from visual scenes during navigation. To test this idea, we used transcranial magnetic stimulation (TMS) to interrupt processing in the OPA while subjects performed a virtual-reality memory task that required them to learn the spatial locations of test objects that were either fixed in place relative to the boundary of the environment or moved in tandem with a landmark object. Consistent with our prediction, we found that TMS to the right OPA impaired spatial memory for boundary-tethered, but not landmark-tethered, objects. Moreover, this effect was found when the boundary was defined by a wall, but not when it was defined by a marking on the ground. These results show that the OPA is causally involved in boundary-based spatial navigation and suggest that the OPA is the perceptual source of the boundary information that controls navigational behavior.
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Affiliation(s)
- Joshua B Julian
- Department of Psychology, University of Pennsylvania, Philadelphia, PA 19104, USA.
| | - Jack Ryan
- Department of Psychology, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Roy H Hamilton
- Department of Neurology, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Russell A Epstein
- Department of Psychology, University of Pennsylvania, Philadelphia, PA 19104, USA
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Yang Y. Is There a Common Summary Statistical Process for Representing the Mean and Variance? A Study Using Illustrations of Familiar Items. Iperception 2018; 9:2041669517747297. [PMID: 29399318 PMCID: PMC5788105 DOI: 10.1177/2041669517747297] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
A number of studies revealed that our visual system can extract different types of summary statistics, such as the mean and variance, from sets of items. Although the extraction of such summary statistics has been studied well in isolation, the relationship between these statistics remains unclear. In this study, we explored this issue using an individual differences approach. Observers viewed illustrations of strawberries and lollypops varying in size or orientation and performed four tasks in a within-subject design, namely mean and variance discrimination tasks with size and orientation domains. We found that the performances in the mean and variance discrimination tasks were not correlated with each other and demonstrated that extractions of the mean and variance are mediated by different representation mechanisms. In addition, we tested the relationship between performances in size and orientation domains for each summary statistic (i.e. mean and variance) and examined whether each summary statistic has distinct processes across perceptual domains. The results illustrated that statistical summary representations of size and orientation may share a common mechanism for representing the mean and possibly for representing variance. Introspections for each observer performing the tasks were also examined and discussed.
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Affiliation(s)
- Yi Yang
- Graduate School of Humanities and Sciences, Ochanomizu University, Tokyo, Japan
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Utochkin IS, Vostrikov KO. The numerosity and mean size of multiple objects are perceived independently and in parallel. PLoS One 2017; 12:e0185452. [PMID: 28957361 PMCID: PMC5619754 DOI: 10.1371/journal.pone.0185452] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2017] [Accepted: 09/12/2017] [Indexed: 11/19/2022] Open
Abstract
It is well documented that people are good at the rapid representation of multiple objects in the form of ensemble summary statistics of different types (numerosity, the average feature, the variance of features, etc.). However, there is not enough clarity regarding the links between statistical domains. The relations between different-type summaries (numerosity and the mean) are of particular interest, since they can shed light on (1) a very general functional organization of ensemble processing and (2) mechanisms of statistical computations (whether averaging takes into account numerical information, as in regular statistics). Here, we show no correlation between the precision of estimated numerosity and that of the estimated mean. We also found that people are very good at dividing attention between numerosity and the mean size of a single set (Experiment 1); however, they show some cost of dividing attention between two same-type (two numerosities or two mean sizes, Experiment 2) and two different-type (one numerosity and one mean size, Experiment 3) summaries when each summary is ascribed to a different set. These results support the idea of domain specificity of numerosity and mean size perception, which also implies that, unlike regular statistics, computing the mean does not require numerosity information. We also conclude that computational capacity of ensemble statistics is more limited by encoding several ensembles than computing several summaries.
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Affiliation(s)
- Igor S. Utochkin
- National Research University Higher School of Economics, Moscow, Russia
- * E-mail:
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