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Rolls ET. Two what, two where, visual cortical streams in humans. Neurosci Biobehav Rev 2024; 160:105650. [PMID: 38574782 DOI: 10.1016/j.neubiorev.2024.105650] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2023] [Revised: 03/25/2024] [Accepted: 03/31/2024] [Indexed: 04/06/2024]
Abstract
ROLLS, E. T. Two What, Two Where, Visual Cortical Streams in Humans. NEUROSCI BIOBEHAV REV 2024. Recent cortical connectivity investigations lead to new concepts about 'What' and 'Where' visual cortical streams in humans, and how they connect to other cortical systems. A ventrolateral 'What' visual stream leads to the inferior temporal visual cortex for object and face identity, and provides 'What' information to the hippocampal episodic memory system, the anterior temporal lobe semantic system, and the orbitofrontal cortex emotion system. A superior temporal sulcus (STS) 'What' visual stream utilising connectivity from the temporal and parietal visual cortex responds to moving objects and faces, and face expression, and connects to the orbitofrontal cortex for emotion and social behaviour. A ventromedial 'Where' visual stream builds feature combinations for scenes, and provides 'Where' inputs via the parahippocampal scene area to the hippocampal episodic memory system that are also useful for landmark-based navigation. The dorsal 'Where' visual pathway to the parietal cortex provides for actions in space, but also provides coordinate transforms to provide inputs to the parahippocampal scene area for self-motion update of locations in scenes in the dark or when the view is obscured.
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Affiliation(s)
- Edmund T Rolls
- Oxford Centre for Computational Neuroscience, Oxford, UK; Department of Computer Science, University of Warwick, Coventry CV4 7AL, UK; Institute of Science and Technology for Brain Inspired Intelligence, Fudan University, Shanghai 200403, China.
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Rolls ET. Hippocampal spatial view cells for memory and navigation, and their underlying connectivity in humans. Hippocampus 2023; 33:533-572. [PMID: 36070199 PMCID: PMC10946493 DOI: 10.1002/hipo.23467] [Citation(s) in RCA: 17] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2022] [Revised: 08/16/2022] [Accepted: 08/16/2022] [Indexed: 01/08/2023]
Abstract
Hippocampal and parahippocampal gyrus spatial view neurons in primates respond to the spatial location being looked at. The representation is allocentric, in that the responses are to locations "out there" in the world, and are relatively invariant with respect to retinal position, eye position, head direction, and the place where the individual is located. The underlying connectivity in humans is from ventromedial visual cortical regions to the parahippocampal scene area, leading to the theory that spatial view cells are formed by combinations of overlapping feature inputs self-organized based on their closeness in space. Thus, although spatial view cells represent "where" for episodic memory and navigation, they are formed by ventral visual stream feature inputs in the parahippocampal gyrus in what is the parahippocampal scene area. A second "where" driver of spatial view cells are parietal inputs, which it is proposed provide the idiothetic update for spatial view cells, used for memory recall and navigation when the spatial view details are obscured. Inferior temporal object "what" inputs and orbitofrontal cortex reward inputs connect to the human hippocampal system, and in macaques can be associated in the hippocampus with spatial view cell "where" representations to implement episodic memory. Hippocampal spatial view cells also provide a basis for navigation to a series of viewed landmarks, with the orbitofrontal cortex reward inputs to the hippocampus providing the goals for navigation, which can then be implemented by hippocampal connectivity in humans to parietal cortex regions involved in visuomotor actions in space. The presence of foveate vision and the highly developed temporal lobe for object and scene processing in primates including humans provide a basis for hippocampal spatial view cells to be key to understanding episodic memory in the primate and human hippocampus, and the roles of this system in primate including human navigation.
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Affiliation(s)
- Edmund T. Rolls
- Oxford Centre for Computational NeuroscienceOxfordUK
- Department of Computer ScienceUniversity of WarwickCoventryUK
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Liu N, Behrmann M, Turchi JN, Avidan G, Hadj-Bouziane F, Ungerleider LG. Bidirectional and parallel relationships in macaque face circuit revealed by fMRI and causal pharmacological inactivation. Nat Commun 2022; 13:6787. [PMID: 36351907 PMCID: PMC9646786 DOI: 10.1038/s41467-022-34451-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2021] [Accepted: 10/25/2022] [Indexed: 11/11/2022] Open
Abstract
Although the presence of face patches in primate inferotemporal (IT) cortex is well established, the functional and causal relationships among these patches remain elusive. In two monkeys, muscimol was infused sequentially into each patch or pair of patches to assess their respective influence on the remaining IT face network and the amygdala, as determined using fMRI. The results revealed that anterior face patches required input from middle face patches for their responses to both faces and objects, while the face selectivity in middle face patches arose, in part, from top-down input from anterior face patches. Moreover, we uncovered a parallel fundal-lateral functional organization in the IT face network, supporting dual routes (dorsal-ventral) in face processing within IT cortex as well as between IT cortex and the amygdala. Our findings of the causal relationship among the face patches demonstrate that the IT face circuit is organized into multiple functional compartments.
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Affiliation(s)
- Ning Liu
- Section on Neurocircuitry, Laboratory of Brain and Cognition, NIMH, NIH, Bethesda, MD, 20892, USA.
- State Key Laboratory of Brain and Cognitive Science, Institute of Biophysics, Chinese Academy of Sciences, 100101, Beijing, China.
| | - Marlene Behrmann
- Department of Ophthalmology, University of Pittsburgh, Pittsburgh, PA, 15213, USA
- Department of Psychology and Neuroscience Institute, Carnegie Mellon University, Pittsburgh, PA, 15213, USA
| | - Janita N Turchi
- Laboratory of Neuropsychology, NIMH, NIH, Bethesda, MD, 20892, USA
| | - Galia Avidan
- Department of Psychology, Ben-Gurion University of the Negev, Beer-Sheva, 8410501, Israel
| | - Fadila Hadj-Bouziane
- Section on Neurocircuitry, Laboratory of Brain and Cognition, NIMH, NIH, Bethesda, MD, 20892, USA
- INSERM, U1028, CNRS UMR5292, Lyon Neuroscience Research Center, ImpAct Team, F-69000, Lyon, France
- University UCBL Lyon 1, F-69000, Lyon, France
| | - Leslie G Ungerleider
- Section on Neurocircuitry, Laboratory of Brain and Cognition, NIMH, NIH, Bethesda, MD, 20892, USA
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Bittencourt M, van der Horn HJ, Balart-Sánchez SA, Marsman JC, van der Naalt J, Maurits NM. Effects of Mild Traumatic Brain Injury on Resting State Brain Network Connectivity in Older Adults. Brain Imaging Behav 2022. [PMID: 35394617 DOI: 10.1007/s11682-022-00662-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/10/2022] [Indexed: 11/02/2022]
Abstract
Older age is associated with worsened outcome after mild traumatic brain injury (mTBI) and a higher risk of developing persistent post-traumatic complaints. However, the effects of mTBI sequelae on brain connectivity at older age and their association with post-traumatic complaints remain understudied.We analyzed multi-echo resting-state functional magnetic resonance imaging data from 25 older adults with mTBI (mean age: 68 years, SD: 5 years) in the subacute phase (mean injury to scan interval: 38 days, SD: 9 days) and 20 age-matched controls. Severity of complaints (e.g. fatigue, dizziness) was assessed using self-reported questionnaires. Group independent component analysis was used to identify intrinsic connectivity networks (ICNs). The effects of group and severity of complaints on ICNs were assessed using spatial maps intensity (SMI) as a measure of within-network connectivity, and (static) functional network connectivity (FNC) as a measure of between-network connectivity.Patients indicated a higher total severity of complaints than controls. Regarding SMI measures, we observed hyperconnectivity in left-mid temporal gyrus (cognitive-language network) and hypoconnectivity in the right-fusiform gyrus (visual-cerebellar network) that were associated with group. Additionally, we found interaction effects for SMI between severity of complaints and group in the visual(-cerebellar) domain. Regarding FNC measures, no significant effects were found.In older adults, changes in cognitive-language and visual(-cerebellar) networks are related to mTBI. Additionally, group-dependent associations between connectivity within visual(-cerebellar) networks and severity of complaints might indicate post-injury (mal)adaptive mechanisms, which could partly explain post-traumatic complaints (such as dizziness and balance disorders) that are common in older adults during the subacute phase.
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Staib M, Frühholz S. Distinct functional levels of human voice processing in the auditory cortex. Cereb Cortex 2022; 33:1170-1185. [PMID: 35348635 PMCID: PMC9930621 DOI: 10.1093/cercor/bhac128] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2021] [Revised: 02/03/2022] [Accepted: 03/07/2022] [Indexed: 11/12/2022] Open
Abstract
Voice signaling is integral to human communication, and a cortical voice area seemed to support the discrimination of voices from other auditory objects. This large cortical voice area in the auditory cortex (AC) was suggested to process voices selectively, but its functional differentiation remained elusive. We used neuroimaging while humans processed voices and nonvoice sounds, and artificial sounds that mimicked certain voice sound features. First and surprisingly, specific auditory cortical voice processing beyond basic acoustic sound analyses is only supported by a very small portion of the originally described voice area in higher-order AC located centrally in superior Te3. Second, besides this core voice processing area, large parts of the remaining voice area in low- and higher-order AC only accessorily process voices and might primarily pick up nonspecific psychoacoustic differences between voices and nonvoices. Third, a specific subfield of low-order AC seems to specifically decode acoustic sound features that are relevant but not exclusive for voice detection. Taken together, the previously defined voice area might have been overestimated since cortical support for human voice processing seems rather restricted. Cortical voice processing also seems to be functionally more diverse and embedded in broader functional principles of the human auditory system.
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Affiliation(s)
- Matthias Staib
- Cognitive and Affective Neuroscience Unit, University of Zurich, 8050 Zurich, Switzerland
| | - Sascha Frühholz
- Corresponding author: Department of Psychology, University of Zürich, Binzmuhlestrasse 14/18, 8050 Zürich, Switzerland.
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Passarelli M, Masini M, Chiorri C, Nurcis A, Daini R, Bracco F. Implicit evidence on the dissociation of identity and emotion recognition. Cogn Process 2021; 23:79-90. [PMID: 34618254 DOI: 10.1007/s10339-021-01061-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2021] [Accepted: 09/07/2021] [Indexed: 11/29/2022]
Abstract
Recognition of identity and of emotional facial expressions of individuals are both based on processing of the human face. While most studies show these abilities to be dissociated, some others find evidence of a connection. One possible explanation for these contradictory results comes from neurological evidence, which points to identity recognition being mostly based on holistic processing, while emotion recognition seems to be based on both an explicit, fine-grained process, and an implicit, mostly-holistic one. Our main hypothesis, that would explain the contradictory findings, is that holistic implicit emotion recognition, specifically, would be related to identity recognition, while explicit emotion recognition would be a process separate to identity recognition. To test this hypothesis, we employed an experimental paradigm in which spatial frequencies of visual stimuli are manipulated so that automatic, holistic-based, implicit emotion recognition influences perceived friendliness of unfamiliar faces. We predicted the effect to be related to identity recognition ability, since they both require holistic face processing. After a successful replication study, we employed the paradigm with 140 participants, measuring also identity recognition ability and explicit emotion recognition ability. Results showed that the effect is not moderated by these two variables (p = .807 and .373, respectively), suggesting that the independence of identity and emotion recognition holds even when considering, specifically, implicit emotion recognition.
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Affiliation(s)
- Marcello Passarelli
- ITD - Consiglio Nazionale delle Ricerche, Via de Marini 6, 16149, Genova, Italy.
| | - Michele Masini
- V.I.E. (Valorizzazione Innovazione Empowerment), Viale Brigata Bisagno 12/4, 16129, Genova, Italy
| | - Carlo Chiorri
- Dipartimento di Scienze della Formazione, Università degli Studi di Genova, Corso Andrea Podestà 2, 16139, Genova, Italy
| | - Alessandro Nurcis
- Dipartimento di Scienze della Formazione, Università degli Studi di Genova, Corso Andrea Podestà 2, 16139, Genova, Italy
| | - Roberta Daini
- Dipartimento di Psicologia, Università degli Studi di Milano-Bicocca, Piazza dell'Ateneo Nuovo, 1, 20126, Milano, Italy
| | - Fabrizio Bracco
- Dipartimento di Scienze della Formazione, Università degli Studi di Genova, Corso Andrea Podestà 2, 16139, Genova, Italy
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Seider TR, Porges EC, Woods AJ, Cohen RA. Dedifferentiation of Functional Brain Activation Associated With Greater Visual Discrimination Accuracy in Middle-Aged and Older Adults. Front Aging Neurosci 2021; 13:651284. [PMID: 34366822 PMCID: PMC8336636 DOI: 10.3389/fnagi.2021.651284] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2021] [Accepted: 06/17/2021] [Indexed: 11/13/2022] Open
Abstract
Neural dedifferentiation refers to an age-related phenomenon whereby brain functions that are localized to specific, distinct, and differentiated brain areas in young adults become less so as people reach more advanced age. Older adults tend to exhibit greater spread of cortical activation on fMRI during cognitive processing compared to younger adults, with evidence that this occurs during visuoperceptual processing. Some age-related functional changes are considered compensatory, but whether dedifferentiation is compensatory is not clearly understood. The current study assessed dedifferentiation and visual discrimination performance during simultaneous match-to-sample tasks from the Visual Assessment Battery (VAB) among 40 healthy middle-aged and older adults using fMRI. Task-relevant regions of interest (ROIs) were created in the dorsal stream for discrimination of spatial location, the ventral stream for shape, and an area encompassing V5 for velocity. Dedifferentiation, or less specificity in functional activation, was associated with greater discrimination accuracy and more years of education. Secondary analyses showed that reduced functional activation in task-relevant ROIs was associated with faster discrimination speed. Age was unassociated with functional activation. Results suggest that dedifferentiation is compensatory. Lack of age effects suggest that other factors beyond age, such as cognitive or brain reserve, may better predict performance when considering cognitive skills that are relatively stable as adults age, such as visual discrimination.
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Affiliation(s)
- Talia R Seider
- Center for Cognitive Aging and Memory, Clinical Translational Research Program, Department of Clinical and Health Psychology, University of Florida, Gainesville, FL, United States
| | - Eric C Porges
- Center for Cognitive Aging and Memory, Clinical Translational Research Program, Department of Clinical and Health Psychology, University of Florida, Gainesville, FL, United States
| | - Adam J Woods
- Center for Cognitive Aging and Memory, Clinical Translational Research Program, Department of Clinical and Health Psychology, University of Florida, Gainesville, FL, United States
| | - Ronald A Cohen
- Center for Cognitive Aging and Memory, Clinical Translational Research Program, Department of Clinical and Health Psychology, University of Florida, Gainesville, FL, United States
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Walbrin J, Almeida J. High-Level Representations in Human Occipito-Temporal Cortex Are Indexed by Distal Connectivity. J Neurosci 2021; 41:4678-4685. [PMID: 33849949 PMCID: PMC8260247 DOI: 10.1523/jneurosci.2857-20.2021] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2020] [Revised: 03/09/2021] [Accepted: 03/15/2021] [Indexed: 12/30/2022] Open
Abstract
Human object recognition is dependent on occipito-temporal cortex (OTC), but a complete understanding of the complex functional architecture of this area must account for how it is connected to the wider brain. Converging functional magnetic resonance imaging evidence shows that univariate responses to different categories of information (e.g., faces, bodies, and nonhuman objects) are strongly related to, and potentially shaped by, functional and structural connectivity to the wider brain. However, to date, there have been no systematic attempts to determine how distal connectivity and complex local high-level responses in occipito-temporal cortex (i.e., multivoxel response patterns) are related. Here, we show that distal functional connectivity is related to, and can reliably index, high-level representations for several visual categories (i.e., tools, faces, and places) within occipito-temporal cortex; that is, voxel sets that are strongly connected to distal brain areas show higher pattern discriminability than less well-connected sets do. We further show that in several cases, pattern discriminability is higher in sets of well-connected voxels than sets defined by local activation (e.g., strong amplitude responses to faces in fusiform face area). Together, these findings demonstrate the important relationship between the complex functional organization of occipito-temporal cortex and wider brain connectivity.SIGNIFICANCE STATEMENT Human object recognition relies strongly on OTC, yet responses in this broad area are often considered in relative isolation to the rest of the brain. We employ a novel connectivity-guided voxel selection approach with functional magnetic resonance imaging data to show higher sensitivity to information (i.e., higher multivoxel pattern discriminability) in voxel sets that share strong connectivity to distal brain areas, relative to (1) voxel sets that are less strongly connected, and in several cases, (2) voxel sets that are defined by strong local response amplitude. These findings underscore the importance of distal contributions to local processing in OTC.
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Affiliation(s)
- Jon Walbrin
- Proaction Laboratory, Faculty of Psychology and Educational Sciences, University of Coimbra, 3004-531 Coimbra, Portugal
| | - Jorge Almeida
- Proaction Laboratory, Faculty of Psychology and Educational Sciences, University of Coimbra, 3004-531 Coimbra, Portugal
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Weisberg SM, Ekstrom AD. Hippocampal volume and navigational ability: The map(ping) is not to scale. Neurosci Biobehav Rev 2021; 126:102-12. [PMID: 33722618 DOI: 10.1016/j.neubiorev.2021.03.012] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2020] [Revised: 01/19/2021] [Accepted: 03/08/2021] [Indexed: 11/22/2022]
Abstract
A critical question regards the neural basis of complex cognitive skill acquisition. One extensively studied skill is navigation, with evidence suggesting that humans vary widely in navigation abilities. Yet, data supporting the neural underpinning of these individual differences are mixed. Some evidence suggests robust structure-behavior relations between hippocampal volume and navigation ability, whereas other experiments show no such correlation. We focus on several possibilities for these discrepancies: 1) volumetric hippocampal changes are relevant only at the extreme ranges of navigational abilities; 2) hippocampal volume correlates across individuals but only for specific measures of navigation skill; 3) hippocampal volume itself does not correlate with navigation skill acquisition; connectivity patterns are more relevant. To explore this third possibility, we present a model emphasizing functional connectivity changes, particularly to extra-hippocampal structures. This class of models arises from the premise that navigation is dynamic and that good navigators flexibly solve spatial challenges. These models pave the way for research on other skills and provide more precise predictions for the neural basis of skill acquisition.
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Burns EJ, Arnold T, Bukach CM. P-curving the fusiform face area: Meta-analyses support the expertise hypothesis. Neurosci Biobehav Rev 2019; 104:209-21. [DOI: 10.1016/j.neubiorev.2019.07.003] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2018] [Revised: 06/30/2019] [Accepted: 07/01/2019] [Indexed: 11/22/2022]
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Abstract
Many cognitive abilities decline with age even in the absence of detectable pathology. Recent evidence indicates that age-related neural dedifferentiation, operationalized in terms of neural selectivity, may contribute to this decline. We review here work exploring the relationship between neural dedifferentiation, cognition, and age. Compelling evidence for age effects on neural selectivity comes from both non-human animal and human research. However, current data suggest that age does not moderate the observed relationships between neural dedifferentiation and cognitive performance. We propose that functionally significant variance in measures of neural dedifferentiation reflects both age-dependent and age-independent factors. We further propose that the effects of age on neural dedifferentiation do not exclusively reflect detrimental consequences of aging.
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Affiliation(s)
- Joshua D Koen
- Department of Psychology, University of Notre Dame, Notre Dame, IN 46556, USA.
| | - Michael D Rugg
- Center for Vital Longevity, School of Behavioral and Brain Sciences, University of Texas at Dallas, Richardson, TX 75235, USA
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Holzinger Y, Ullman S, Harari D, Behrmann M, Avidan G. Minimal Recognizable Configurations Elicit Category-selective Responses in Higher Order Visual Cortex. J Cogn Neurosci 2019; 31:1354-1367. [PMID: 31059350 DOI: 10.1162/jocn_a_01420] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
Visual object recognition is performed effortlessly by humans notwithstanding the fact that it requires a series of complex computations, which are, as yet, not well understood. Here, we tested a novel account of the representations used for visual recognition and their neural correlates using fMRI. The rationale is based on previous research showing that a set of representations, termed "minimal recognizable configurations" (MIRCs), which are computationally derived and have unique psychophysical characteristics, serve as the building blocks of object recognition. We contrasted the BOLD responses elicited by MIRC images, derived from different categories (faces, objects, and places), sub-MIRCs, which are visually similar to MIRCs, but, instead, result in poor recognition and scrambled, unrecognizable images. Stimuli were presented in blocks, and participants indicated yes/no recognition for each image. We confirmed that MIRCs elicited higher recognition performance compared to sub-MIRCs for all three categories. Whereas fMRI activation in early visual cortex for both MIRCs and sub-MIRCs of each category did not differ from that elicited by scrambled images, high-level visual regions exhibited overall greater activation for MIRCs compared to sub-MIRCs or scrambled images. Moreover, MIRCs and sub-MIRCs from each category elicited enhanced activation in corresponding category-selective regions including fusiform face area and occipital face area (faces), lateral occipital cortex (objects), and parahippocampal place area and transverse occipital sulcus (places). These findings reveal the psychological and neural relevance of MIRCs and enable us to make progress in developing a more complete account of object recognition.
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Barry DN, Barnes GR, Clark IA, Maguire EA. The Neural Dynamics of Novel Scene Imagery. J Neurosci 2019; 39:4375-86. [PMID: 30902867 DOI: 10.1523/JNEUROSCI.2497-18.2019] [Citation(s) in RCA: 63] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2018] [Revised: 03/06/2019] [Accepted: 03/07/2019] [Indexed: 12/16/2022] Open
Abstract
Retrieval of long-term episodic memories is characterized by synchronized neural activity between hippocampus and ventromedial prefrontal cortex (vmPFC), with additional evidence that vmPFC activity leads that of the hippocampus. It has been proposed that the mental generation of scene imagery is a crucial component of episodic memory processing. If this is the case, then a comparable interaction between the two brain regions should exist during the construction of novel scene imagery. To address this question, we leveraged the high temporal resolution of MEG to investigate the construction of novel mental imagery. We tasked male and female humans with imagining scenes and single isolated objects in response to one-word cues. We performed source-level power, coherence, and causality analyses to characterize the underlying interregional interactions. Both scene and object imagination resulted in theta power changes in the anterior hippocampus. However, higher theta coherence was observed between the hippocampus and vmPFC in the scene compared with the object condition. This interregional theta coherence also predicted whether imagined scenes were subsequently remembered. Dynamic causal modeling of this interaction revealed that vmPFC drove activity in hippocampus during novel scene construction. Additionally, theta power changes in the vmPFC preceded those observed in the hippocampus. These results constitute the first evidence in humans that episodic memory retrieval and scene imagination rely on similar vmPFC–hippocampus neural dynamics. Furthermore, they provide support for theories emphasizing similarities between both cognitive processes and perspectives that propose the vmPFC guides the construction of context-relevant representations in the hippocampus. SIGNIFICANCE STATEMENT Episodic memory retrieval is characterized by a dialog between hippocampus and ventromedial prefrontal cortex (vmPFC). It has been proposed that the mental generation of scene imagery is a crucial component of episodic memory processing. An ensuing prediction would be of a comparable interaction between the two brain regions during the construction of novel scene imagery. Here, we leveraged the high temporal resolution of MEG and combined it with a scene imagination task. We found that a hippocampal–vmPFC dialog existed and that it took the form of vmPFC driving the hippocampus. We conclude that episodic memory and scene imagination share fundamental neural dynamics and the process of constructing vivid, spatially coherent, contextually appropriate scene imagery is strongly modulated by vmPFC.
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Shulman RG, Rothman DL. A Non-cognitive Behavioral Model for Interpreting Functional Neuroimaging Studies. Front Hum Neurosci 2019; 13:28. [PMID: 30914933 PMCID: PMC6421518 DOI: 10.3389/fnhum.2019.00028] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2018] [Accepted: 01/21/2019] [Indexed: 12/17/2022] Open
Abstract
The dominant model for interpreting brain imaging experiments, which we refer to as the Standard Cognitive Model (SCM), assumes that the brain is organized in support of mental processes that control behavior. However, functional neuroimaging experiments of cognitive tasks have not shown clear anatomic segregation between mental processes originally proposed by this model. This failing has been blamed on limitations in imaging technology and non-linearity in the brain’s implementation of these processes. However, the validity of the underlying cognitive models used to describe the brain has rarely been questioned or directly tested against imaging results. We propose an alternative model of brain function, that we term the Non-cognitive Behavioral Model (NBM), which correlates observed human behavior directly with measured brain activity without making assumptions about intervening cognitive processes. Our model derives from behavioral psychology but is extended to include brain activity, in addition to behavior, as observables. A further extension is the role of neuroplasticity, as opposed to innate cognitive processes, in developing the brain’s support of cognitive behavior. We present the theoretical basis with which the SCM maps cognitive processes onto functional magnetic resonance and positron emission tomography images and compare and contrast with the NBM. We also describe how the NBM can be used experimentally to study how the brain supports behavior. Two applications are presented that support the usefulness of the NBM. In one, the NBM use of the total functional imaging signal (not just the differences between states) provides a stronger correlation of neural activity with the behavioral state of consciousness than the SCM approach in both anesthesia and coma. The second example reviews studies of facial and object recognition that provide evidence for the NBM proposal that neuroplasticity and experience play key roles in the brain’s support of recognition and other behaviors. The conclusions regarding neuroplasticity are then generalized to explain the incomplete functional segregation observed in the application of the SCM to neuroimaging.
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Affiliation(s)
- Robert G Shulman
- Magnetic Resonance Research Center, Department of Radiology, Yale University School of Medicine, New Haven, CT, United States.,Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, United States
| | - Douglas L Rothman
- Magnetic Resonance Research Center, Department of Radiology, Yale University School of Medicine, New Haven, CT, United States
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Nishio N, Tsukano H, Hishida R, Abe M, Nakai J, Kawamura M, Aiba A, Sakimura K, Shibuki K. Higher visual responses in the temporal cortex of mice. Sci Rep 2018; 8:11136. [PMID: 30042474 DOI: 10.1038/s41598-018-29530-3] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2018] [Accepted: 07/14/2018] [Indexed: 01/17/2023] Open
Abstract
The visual cortex of mice is a useful model for investigating the mammalian visual system. In primates, higher visual areas are classified into two parts, the dorsal stream (“where” pathway) and ventral stream (“what” pathway). The ventral stream is known to include a part of the temporal cortex. In mice, however, some cortical areas adjacent to the primary visual area (V1) in the occipital cortex are thought to be comparable to the ventral stream in primates, although the whole picture of the mouse ventral stream has never been elucidated. We performed wide-field Ca2+ imaging in awake mice to investigate visual responses in the mouse temporal cortex, and found that the postrhinal cortex (POR), posterior to the auditory cortex (AC), and the ectorhinal and temporal association cortices (ECT), ventral to the AC, showed clear visual responses to moving visual objects. The retinotopic maps in the POR and ECT were not clearly observed, and the amplitudes of the visual responses in the POR and ECT were less sensitive to the size of the objects, compared to visual responses in the V1. In the ECT, objects of different sizes activated different subareas. These findings strongly suggest that the mouse ventral stream extends to the ECT ventral to the AC, and that it has characteristic response properties that are markedly different from the response properties in the V1.
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16
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Shehzad Z, McCarthy G. Category representations in the brain are both discretely localized and widely distributed. J Neurophysiol 2018; 119:2256-2264. [PMID: 29537922 PMCID: PMC6032110 DOI: 10.1152/jn.00912.2017] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2017] [Revised: 03/05/2018] [Accepted: 03/05/2018] [Indexed: 11/22/2022] Open
Abstract
Whether category information is discretely localized or represented widely in the brain remains a contentious issue. Initial functional MRI studies supported the localizationist perspective that category information is represented in discrete brain regions. More recent fMRI studies using machine learning pattern classification techniques provide evidence for widespread distributed representations. However, these latter studies have not typically accounted for shared information. Here, we find strong support for distributed representations when brain regions are considered separately. However, localized representations are revealed by using analytical methods that separate unique from shared information among brain regions. The distributed nature of shared information and the localized nature of unique information suggest that brain connectivity may encourage spreading of information but category-specific computations are carried out in distinct domain-specific regions. NEW & NOTEWORTHY Whether visual category information is localized in unique domain-specific brain regions or distributed in many domain-general brain regions is hotly contested. We resolve this debate by using multivariate analyses to parse functional MRI signals from different brain regions into unique and shared variance. Our findings support elements of both models and show information is initially localized and then shared among other regions leading to distributed representations being observed.
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Affiliation(s)
- Zarrar Shehzad
- Department of Psychology, Yale University , New Haven, Connecticut
| | - Gregory McCarthy
- Department of Psychology, Yale University , New Haven, Connecticut
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17
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Weiner KS, Natu VS, Grill-Spector K. On object selectivity and the anatomy of the human fusiform gyrus. Neuroimage 2018; 173:604-609. [PMID: 29471101 DOI: 10.1016/j.neuroimage.2018.02.040] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2017] [Revised: 02/13/2018] [Accepted: 02/18/2018] [Indexed: 11/15/2022] Open
Abstract
pFs is a functionally-defined region in the human brain that is involved in recognizing objects. A recent trend refers to pFs as the posterior fusiform sulcus, which is a neuroanatomical structure that does not exist. Here, we correct this mistake. To achieve this goal, we first recount the original definitions of pFs and then review the identification of sulci within and surrounding the fusiform gyrus (FG) including the mid-fusiform sulcus (MFS), which is a tertiary sulcus within the FG. We highlight that tertiary sulci, such as the MFS, are often absent from brain atlases, which complicates the accurate localization of functional regions, as well as the understanding of structural-functional relationships in ventral temporal cortex (VTC). When considering the location of object-selective pFs from previously published data relative to the sulci surrounding the FG, as well as the MFS, we illustrate that (1) pFs spans several macroanatomical structures, which is consistent with the original definitions of pFs (Grill-Spector et al., 1999, 2000), and (2) the topological relationship between pFs and MFS has both stable and variable features. To prevent future confusion regarding the anatomical location of functional regions within VTC, as well as to complement tools that automatically identify sulci surrounding the FG, we provide a method to automatically identify the MFS in individual brains using FreeSurfer. Finally, we highlight the benefits of using cortical surface reconstructions in large datasets to identify and quantify tertiary sulci compared to classic dissection methods because the latter often fail to differentiate tertiary sulci from shallow surface indentations produced by veins and arteries. Altogether, we propose that the inclusion of definitions and labels for tertiary sulci in neuroanatomical atlases and neuroimaging software packages will enhance understanding of functional-structural relationships throughout the human brain.
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Affiliation(s)
- Kevin S Weiner
- Department of Psychology, University of California, Berkeley, Berkeley, CA 94720, USA; Helen Wills Neuroscience Institute, University of California, Berkeley, Berkeley, CA 94720, USA.
| | - Vaidehi S Natu
- Department of Neurological Surgery, University of Texas Southwestern Medical Centre, TX 75390, USA; Department of Psychology, Stanford University, Stanford, CA 94305, USA
| | - Kalanit Grill-Spector
- Department of Psychology, Stanford University, Stanford, CA 94305, USA; Stanford Neurosciences Institute, Stanford University, Stanford, CA 94305, USA
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18
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Wang B, Li T, Niu Y, Xiang J, Cheng J, Liu B, Zhang H, Yan T, Kanazawa S, Wu J. Differences in neural responses to ipsilateral stimuli in wide-view fields between face- and house-selective areas. PLoS One 2018; 13:e0192532. [PMID: 29451872 PMCID: PMC5815592 DOI: 10.1371/journal.pone.0192532] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2017] [Accepted: 01/25/2018] [Indexed: 11/18/2022] Open
Abstract
Category-selective brain areas exhibit varying levels of neural activity to ipsilaterally presented stimuli. However, in face- and house-selective areas, the neural responses evoked by ipsilateral stimuli in the peripheral visual field remain unclear. In this study, we displayed face and house images using a wide-view visual presentation system while performing functional magnetic resonance imaging (fMRI). The face-selective areas (fusiform face area (FFA) and occipital face area (OFA)) exhibited intense neural responses to ipsilaterally presented images, whereas the house-selective areas (parahippocampal place area (PPA) and transverse occipital sulcus (TOS)) exhibited substantially smaller and even negative neural responses to the ipsilaterally presented images. We also found that the category preferences of the contralateral and ipsilateral neural responses were similar. Interestingly, the face- and house-selective areas exhibited neural responses to ipsilateral images that were smaller than the responses to the contralateral images. Multi-voxel pattern analysis (MVPA) was implemented to evaluate the difference between the contralateral and ipsilateral responses. The classification accuracies were much greater than those expected by chance. The classification accuracies in the FFA were smaller than those in the PPA and TOS. The closer eccentricities elicited greater classification accuracies in the PPA and TOS. We propose that these ipsilateral neural responses might be interpreted by interhemispheric communication through intrahemispheric connectivity of white matter connection and interhemispheric connectivity via the corpus callosum and occipital white matter connection. Furthermore, the PPA and TOS likely have weaker interhemispheric communication than the FFA and OFA, particularly in the peripheral visual field.
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Affiliation(s)
- Bin Wang
- College of Computer Science and Technology, Taiyuan University of Technology, Taiyuan, Shanxi, China
- Department of Radiology, First Hospital of Shanxi Medical University, Taiyuan, Shanxi, China
- * E-mail: (BW); (TY); (HZ); (JW)
| | - Ting Li
- College of Computer Science and Technology, Taiyuan University of Technology, Taiyuan, Shanxi, China
| | - Yan Niu
- College of Computer Science and Technology, Taiyuan University of Technology, Taiyuan, Shanxi, China
| | - Jie Xiang
- College of Computer Science and Technology, Taiyuan University of Technology, Taiyuan, Shanxi, China
| | - Junjie Cheng
- College of Computer Science and Technology, Taiyuan University of Technology, Taiyuan, Shanxi, China
| | - Bo Liu
- Department of Radiology, First Hospital of Shanxi Medical University, Taiyuan, Shanxi, China
| | - Hui Zhang
- Department of Radiology, First Hospital of Shanxi Medical University, Taiyuan, Shanxi, China
- * E-mail: (BW); (TY); (HZ); (JW)
| | - Tianyi Yan
- School of Life Science, Beijing Institute of Technology, Beijing, China
- * E-mail: (BW); (TY); (HZ); (JW)
| | - Susumu Kanazawa
- Graduate School of Medicine, Dentistry, Pharmaceutical Sciences, Okayama University, Okayama, Japan
| | - Jinglong Wu
- Graduate School of Natural Science and Technology, Okayama University, Okayama, Japan
- Key Laboratory of Biomimetic Robots and Systems, Ministry of Education, Beijing Institute of Technology, Beijing, China
- * E-mail: (BW); (TY); (HZ); (JW)
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19
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Abstract
Primates have specialized domains in inferior temporal (IT) cortex that are responsive to particular image categories. Though IT traditionally has been regarded as lacking retinotopy, several recent studies in monkeys have shown that retinotopic maps extend to face patches along the lower bank of the superior temporal sulcus (STS) and neighboring regions of IT cortex. Here, we used fMRI to map the retinotopic organization of medial ventral temporal cortex in four monkeys (2 male and 2 female). We confirm the presence of visual field maps within and around the lower bank of the STS and extend these prior findings to scene-selective cortex in the ventral-most regions of IT. Within the occipitotemporal sulcus (OTS), we identified two retinotopic areas, OTS1 and OTS2. The polar angle representation of OTS2 was a mirror reversal of the OTS1 representation. These regions contained representations of the contralateral periphery and were selectively active for scene versus face, body, or object images. The extent of this retinotopy parallels that in humans and shows that the organization of the scene network is preserved across primate species. In addition retinotopic maps were identified in dorsal extrastriate, posterior parietal, and frontal cortex as well as the thalamus, including both the lateral geniculate nucleus and pulvinar. Together, it appears that most, if not all, of the macaque visual system contains organized representations of visual space.SIGNIFICANCE STATEMENT Primates have specialized domains in inferior temporal (IT) cortex that are responsive to particular image categories. Though retinotopic maps are considered a fundamental organizing principle of posterior visual cortex, IT traditionally has been regarded as lacking retinotopy. Recent imaging studies have demonstrated the presence of several visual field maps within the lateral IT. Using neuroimaging, we found multiple representations of visual space within ventral IT cortex of macaques that included scene-selective cortex. Scene domains were biased toward the peripheral visual field. These data demonstrate the prevalence of visual field maps throughout the primate visual system, including late stages in the ventral visual hierarchy, and support the idea that domains representing different categories are biased toward different parts of the visual field.
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Affiliation(s)
- Michael J Arcaro
- Department of Neurobiology, Harvard Medical School, Boston, Massachusetts 02115
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20
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Çukur T, Huth AG, Nishimoto S, Gallant JL. Functional Subdomains within Scene-Selective Cortex: Parahippocampal Place Area, Retrosplenial Complex, and Occipital Place Area. J Neurosci 2016; 36:10257-73. [PMID: 27707964 DOI: 10.1523/JNEUROSCI.4033-14.2016] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2014] [Accepted: 07/28/2016] [Indexed: 11/21/2022] Open
Abstract
Functional MRI studies suggest that at least three brain regions in human visual cortex-the parahippocampal place area (PPA), retrosplenial complex (RSC), and occipital place area (OPA; often called the transverse occipital sulcus)-represent large-scale information in natural scenes. Tuning of voxels within each region is often assumed to be functionally homogeneous. To test this assumption, we recorded blood oxygenation level-dependent responses during passive viewing of complex natural movies. We then used a voxelwise modeling framework to estimate voxelwise category tuning profiles within each scene-selective region. In all three regions, cluster analysis of the voxelwise tuning profiles reveals two functional subdomains that differ primarily in their responses to animals, man-made objects, social communication, and movement. Thus, the conventional functional definitions of the PPA, RSC, and OPA appear to be too coarse. One attractive hypothesis is that this consistent functional subdivision of scene-selective regions is a reflection of an underlying anatomical organization into two separate processing streams, one selectively biased toward static stimuli and one biased toward dynamic stimuli. SIGNIFICANCE STATEMENT Visual scene perception is a critical ability to survive in the real world. It is therefore reasonable to assume that the human brain contains neural circuitry selective for visual scenes. Here we show that responses in three scene-selective areas-identified in previous studies-carry information about many object and action categories encountered in daily life. We identify two subregions in each area: one that is selective for categories of man-made objects, and another that is selective for vehicles and locomotion-related action categories that appear in dynamic scenes. This consistent functional subdivision may reflect an anatomical organization into two processing streams, one biased toward static stimuli and one biased toward dynamic stimuli.
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21
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Livingstone MS, Vincent JL, Arcaro MJ, Srihasam K, Schade PF, Savage T. Development of the macaque face-patch system. Nat Commun 2017; 8:14897. [PMID: 28361890 PMCID: PMC5381009 DOI: 10.1038/ncomms14897] [Citation(s) in RCA: 53] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2016] [Accepted: 02/10/2017] [Indexed: 11/08/2022] Open
Abstract
Face recognition is highly proficient in humans and other social primates; it emerges in infancy, but the development of the neural mechanisms supporting this behaviour is largely unknown. We use blood-volume functional MRI to monitor longitudinally the responsiveness to faces, scrambled faces, and objects in macaque inferotemporal cortex (IT) from 1 month to 2 years of age. During this time selective responsiveness to monkey faces emerges. Some functional organization is present at 1 month; face-selective patches emerge over the first year of development, and are remarkably stable once they emerge. Face selectivity is refined by a decreasing responsiveness to non-face stimuli.
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Affiliation(s)
| | - Justin L Vincent
- Department of Neurobiology, Harvard Medical School, Boston, Massachusetts 02115, USA
| | - Michael J Arcaro
- Department of Neurobiology, Harvard Medical School, Boston, Massachusetts 02115, USA
| | - Krishna Srihasam
- Department of Neurobiology, Harvard Medical School, Boston, Massachusetts 02115, USA
| | - Peter F Schade
- Department of Neurobiology, Harvard Medical School, Boston, Massachusetts 02115, USA
| | - Tristram Savage
- Department of Neurobiology, Harvard Medical School, Boston, Massachusetts 02115, USA
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22
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Cocchi L, Yang Z, Zalesky A, Stelzer J, Hearne LJ, Gollo LL, Mattingley JB. Neural decoding of visual stimuli varies with fluctuations in global network efficiency. Hum Brain Mapp 2017; 38:3069-3080. [PMID: 28342260 DOI: 10.1002/hbm.23574] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2017] [Revised: 02/25/2017] [Accepted: 03/07/2017] [Indexed: 12/14/2022] Open
Abstract
Functional magnetic resonance imaging (fMRI) studies have shown that neural activity fluctuates spontaneously between different states of global synchronization over a timescale of several seconds. Such fluctuations generate transient states of high and low correlation across distributed cortical areas. It has been hypothesized that such fluctuations in global efficiency might alter patterns of activity in local neuronal populations elicited by changes in incoming sensory stimuli. To test this prediction, we used a linear decoder to discriminate patterns of neural activity elicited by face and motion stimuli presented periodically while participants underwent time-resolved fMRI. As predicted, decoding was reliably higher during states of high global efficiency than during states of low efficiency, and this difference was evident across both visual and nonvisual cortical regions. The results indicate that slow fluctuations in global network efficiency are associated with variations in the pattern of activity across widespread cortical regions responsible for representing distinct categories of visual stimulus. More broadly, the findings highlight the importance of understanding the impact of global fluctuations in functional connectivity on specialized, stimulus driven neural processes. Hum Brain Mapp 38:3069-3080, 2017. © 2017 Wiley Periodicals, Inc.
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Affiliation(s)
- Luca Cocchi
- Queensland Brain Institute, The University of Queensland, Brisbane, Australia.,QIMR Berghofer Medical Research Institute, Brisbane, Australia
| | - Zhengyi Yang
- Queensland Brain Institute, The University of Queensland, Brisbane, Australia.,Brainnetome Center, Institute of Automation, Chinese Academy of Sciences, Beijing, China.,School of Information Technology and Electrical Engineering, The University of Queensland, Brisbane, Australia
| | - Andrew Zalesky
- Melbourne Neuropsychiatry Centre, The University of Melbourne, Melbourne, Australia
| | - Johannes Stelzer
- Department of Biomedical Magnetic Resonance Imaging, University Hospital Tuebingen, Germany.,Magnetic Resonance Centre, Max-Planck-Institute for Biological Cybernetics, Tuebingen, Germany
| | - Luke J Hearne
- Queensland Brain Institute, The University of Queensland, Brisbane, Australia
| | | | - Jason B Mattingley
- Queensland Brain Institute, The University of Queensland, Brisbane, Australia.,School of Psychology, The University of Queensland, Brisbane, Australia
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23
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Praß M, Grimsen C, Fahle M. Functional modulation of contralateral bias in early and object-selective areas after stroke of the occipital ventral cortices. Neuropsychologia 2017; 95:73-85. [PMID: 27956263 DOI: 10.1016/j.neuropsychologia.2016.12.014] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2016] [Revised: 11/14/2016] [Accepted: 12/08/2016] [Indexed: 11/16/2022]
Abstract
Object agnosia is a rare symptom, occurring mainly after bilateral damage of the ventral visual cortex. Most patients suffering from unilateral ventral lesions are clinically non-agnosic. Here, we studied the effect of unilateral occipito-temporal lesions on object categorization and its underlying neural correlates in visual areas. Thirteen non-agnosic stroke patients and twelve control subjects performed an event-related rapid object categorization task in the fMRI scanner where images were presented either to the left or to the right of a fixed point. Eight patients had intact central visual fields within at least 10° eccentricity while five patients showed an incomplete hemianopia. Patients made more errors than controls for both contra- and ipsilesional presentation, meaning that object categorization was impaired bilaterally in both patient groups. The activity in cortical visual areas is usually higher when a stimulus is presented contralaterally compared to presented ipsilaterally (contralateral bias). A region of interest analysis of early visual (V1-V4) and object-selective areas (lateral occipital complex, LOC; fusiform face area, FFA; and parahippocampal place area, PPA) revealed that the lesioned-hemisphere of patients showed reduced contralateral bias in early visual areas and LOC. In contrast, literally no contralateral bias in FFA and PPA was found. These findings indicate disturbed processing in the lesioned hemisphere, which might be related to the processing of visually presented objects. Thus, unilateral occipito-temporal damage leads to altered contralateral bias in the lesioned hemisphere, which might be the cause of impaired categorization performance in both visual hemifields in clinically non-agnosic patients. We conclude that both hemispheres need to be functionally intact for unimpaired object processing.
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Affiliation(s)
- Maren Praß
- Center for Cognitive Science, Human Neurobiology, Bremen University, Hochschulring 18, 28359 Bremen, Germany.
| | - Cathleen Grimsen
- Center for Cognitive Science, Human Neurobiology, Bremen University, Hochschulring 18, 28359 Bremen, Germany.
| | - Manfred Fahle
- Center for Cognitive Science, Human Neurobiology, Bremen University, Hochschulring 18, 28359 Bremen, Germany.
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24
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Affiliation(s)
- Isabel Gauthier
- Department of Psychology, Vanderbilt University, Nashville, Tennessee 37240-7817;
| | - Michael J. Tarr
- Department of Psychology, Center for the Neural Basis of Cognition, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213
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25
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Collins JA, Koski JE, Olson IR. More Than Meets the Eye: The Merging of Perceptual and Conceptual Knowledge in the Anterior Temporal Face Area. Front Hum Neurosci 2016; 10:189. [PMID: 27199711 PMCID: PMC4852584 DOI: 10.3389/fnhum.2016.00189] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2015] [Accepted: 04/14/2016] [Indexed: 11/13/2022] Open
Abstract
An emerging body of research has supported the existence of a small face sensitive region in the ventral anterior temporal lobe (ATL), referred to here as the "anterior temporal face area". The contribution of this region in the greater face-processing network remains poorly understood. The goal of the present study was to test the relative sensitivity of this region to perceptual as well as conceptual information about people and objects. We contrasted the sensitivity of this region to that of two highly-studied face-sensitive regions, the fusiform face area (FFA) and the occipital face area (OFA), as well as a control region in early visual cortex (EVC). Our findings revealed that multivoxel activity patterns in the anterior temporal face area contain information about facial identity, as well as conceptual attributes such as one's occupation. The sensitivity of this region to the conceptual attributes of people was greater than that of posterior face processing regions. In addition, the anterior temporal face area overlaps with voxels that contain information about the conceptual attributes of concrete objects, supporting a generalized role of the ventral ATLs in the identification and conceptual processing of multiple stimulus classes.
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Affiliation(s)
- Jessica A Collins
- Frontotemporal Dementia Unit, Department of Neurology, Massachusetts General Hospital and Harvard Medical School Charlestown, MA, USA
| | - Jessica E Koski
- Department of Psychology, University of Texas Austin Austin, TX, USA
| | - Ingrid R Olson
- Department of Psychology, Temple University Philadelphia, PA, USA
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26
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Zhang W, Wang J, Fan L, Zhang Y, Fox PT, Eickhoff SB, Yu C, Jiang T. Functional organization of the fusiform gyrus revealed with connectivity profiles. Hum Brain Mapp 2016; 37:3003-16. [PMID: 27132874 DOI: 10.1002/hbm.23222] [Citation(s) in RCA: 58] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2015] [Revised: 04/06/2016] [Accepted: 04/10/2016] [Indexed: 11/07/2022] Open
Abstract
Within the object recognition-related ventral visual stream, the human fusiform gyrus (FG), which topographically connects the striate cortex to the inferior temporal lobe, plays a pivotal role in high-level visual/cognitive functions. However, though there are many previous investigations of distinct functional modules within the FG, the functional organization of the whole FG in its full functional heterogeneity has not yet been established. In the current study, a replicable functional organization of the FG based on distinct anatomical connectivity patterns was identified. The FG was parcellated into medial (FGm), lateral (FGl), and anterior (FGa) regions using diffusion tensor imaging. We validated the reasonability of such an organizational scheme from the perspective of resting-state whole brain functional connectivity patterns and the involvement of functional subnetworks. We found corroborating support for these three distinct modules, and suggest that the FGm serves as a transition region that combines multiple stimuli, the FGl is responsible for categorical recognition, and the FGa is involved in semantic understanding. These findings support two organizational functional transitions of the ventral temporal gyrus, a posterior/anterior direction of visual/semantic processing, and a media/lateral direction of high-level visual processing. Our results may facilitate a more detailed study of the human FG in the future. Hum Brain Mapp 37:3003-3016, 2016. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Wen Zhang
- Key Laboratory for NeuroInformation of the Ministry of Education, School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu, China
- School of Computing, Informatics, and Decision Systems Engineering, Arizona State University, Tempe, AZ, USA
| | - Jiaojian Wang
- Key Laboratory for NeuroInformation of the Ministry of Education, School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu, China
| | - Lingzhong Fan
- Brainnetome Center, Institute of Automation, Chinese Academy of Sciences, Beijing, China
| | - Yuanchao Zhang
- Key Laboratory for NeuroInformation of the Ministry of Education, School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu, China
| | - Peter T Fox
- Research Imaging Institute, University of Texas Health Science Center at San Antonio, Texas
| | - Simon B Eickhoff
- Institute of Neuroscience and Medicine (INM-1), Research Centre Jülich, Germany
- Institute of Clinical Neuroscience and Medical Psychology, Heinrich Heine University, Dusseldorf, Germany
| | - Chunshui Yu
- Department of Radiology, Tianjin Medical University General Hospital, Tianjin, China
| | - Tianzi Jiang
- Key Laboratory for NeuroInformation of the Ministry of Education, School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu, China
- Brainnetome Center, Institute of Automation, Chinese Academy of Sciences, Beijing, China
- National Laboratory of Pattern Recognition, Institute of Automation, Chinese Academy of Sciences, Beijing, China
- The Queensland Brain Institute, University of Queensland, Brisbane, QLD, Australia
- CAS Center for Excellence in Brain Science and Intelligence Technology, Institute of Automation, Chinese Academy of Sciences, Beijing, China
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27
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Abstract
Are face and object recognition abilities independent? Although it is commonly believed that they are, Gauthier et al. [Gauthier, I., McGugin, R. W., Richler, J. J., Herzmann, G., Speegle, M., & VanGulick, A. E. Experience moderates overlap between object and face recognition, suggesting a common ability. Journal of Vision, 14, 7, 2014] recently showed that these abilities become more correlated as experience with nonface categories increases. They argued that there is a single underlying visual ability, v, that is expressed in performance with both face and nonface categories as experience grows. Using the Cambridge Face Memory Test and the Vanderbilt Expertise Test, they showed that the shared variance between Cambridge Face Memory Test and Vanderbilt Expertise Test performance increases monotonically as experience increases. Here, we address why a shared resource across different visual domains does not lead to competition and to an inverse correlation in abilities? We explain this conundrum using our neurocomputational model of face and object processing ["The Model", TM, Cottrell, G. W., & Hsiao, J. H. Neurocomputational models of face processing. In A. J. Calder, G. Rhodes, M. Johnson, & J. Haxby (Eds.), The Oxford handbook of face perception. Oxford, UK: Oxford University Press, 2011]. We model the domain general ability v as the available computational resources (number of hidden units) in the mapping from input to label and experience as the frequency of individual exemplars in an object category appearing during network training. Our results show that, as in the behavioral data, the correlation between subordinate level face and object recognition accuracy increases as experience grows. We suggest that different domains do not compete for resources because the relevant features are shared between faces and objects. The essential power of experience is to generate a "spreading transform" for faces (separating them in representational space) that generalizes to objects that must be individuated. Interestingly, when the task of the network is basic level categorization, no increase in the correlation between domains is observed. Hence, our model predicts that it is the type of experience that matters and that the source of the correlation is in the fusiform face area, rather than in cortical areas that subserve basic level categorization. This result is consistent with our previous modeling elucidating why the FFA is recruited for novel domains of expertise [Tong, M. H., Joyce, C. A., & Cottrell, G. W. Why is the fusiform face area recruited for novel categories of expertise? A neurocomputational investigation. Brain Research, 1202, 14-24, 2008].
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28
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CHENG K. What We Have Learned about Human Primary Visual Cortex from High Resolution Functional Magnetic Resonance Imaging. Magn Reson Med Sci 2016; 15:1-10. [DOI: 10.2463/mrms.2015-0008] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Affiliation(s)
- Kang CHENG
- Laboratory for Cognitive Brain Mapping and Support Unit for Functional Magnetic Resonance Imaging, RIKEN Brain Science Institute
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Chung JY, Sung YW, Ogawa S. Evaluation of the Contribution of Signals Originating from Large Blood Vessels to Signals of Functionally Specific Brain Areas. Biomed Res Int 2015; 2015:234345. [PMID: 26413511 DOI: 10.1155/2015/234345] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/14/2014] [Revised: 09/05/2014] [Accepted: 09/19/2014] [Indexed: 11/24/2022]
Abstract
The fusiform face area (FFA) is known to play a pivotal role in face processing. The FFA is located in the ventral region, at the base of the brain, through which large blood vessels run. The location of the FFA via functional MRI (fMRI) may be influenced by these large blood vessels. Responses of large blood vessels may not exactly correspond to neuronal activity in a target area, because they may be diluted and influenced by inflow effects. In this study, we investigated the effects of large blood vessels in the FFA, that is, whether the FFA includes large blood vessels and/or whether inflow signals contribute to fMRI signals of the FFA. For this purpose, we used susceptibility-weighted imaging (SWI) sequences to visualize large blood vessels and dual-echo gradient-echo echo-planar imaging (GE-EPI) to measure inflow effects. These results showed that the location and response signals of the FFA were not influenced by large blood vessels or inflow effects, although large blood vessels were located near the FFA. Therefore, the data from the FFA obtained by individual analysis were robust to large blood vessels but leaving a warning that the data obtained by group analysis may be prone to large blood vessels.
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Farivar R, Grigorov F, van der Kouwe AJ, Wald LL, Keil B. Dense, shape-optimized posterior 32-channel coil for submillimeter functional imaging of visual cortex at 3T. Magn Reson Med 2015. [PMID: 26218835 PMCID: PMC4747861 DOI: 10.1002/mrm.25815] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Purpose Functional neuroimaging of small cortical patches such as columns is essential for testing computational models of vision, but imaging from cortical columns at conventional 3T fields is exceedingly difficult. By targeting the visual cortex exclusively, we tested whether combined optimization of shape, coil placement, and electronics would yield the necessary gains in signal‐to‐noise ratio (SNR) for submillimeter visual cortex functional MRI (fMRI). Method We optimized the shape of the housing to a population‐averaged atlas. The shape was comfortable without cushions and resulted in the maximally proximal placement of the coil elements. By using small wire loops with the least number of solder joints, we were able to maximize the Q factor of the individual elements. Finally, by planning the placement of the coils using the brain atlas, we were able to target the arrangement of the coil elements to the extent of the visual cortex. Results The combined optimizations led to as much as two‐fold SNR gain compared with a whole‐head 32‐channel coil. This gain was reflected in temporal SNR as well and enabled fMRI mapping at 0.75 mm resolutions using a conventional GRAPPA‐accelerated gradient echo echo planar imaging. Conclusion Integrated optimization of shape, electronics, and element placement can lead to large gains in SNR and empower submillimeter fMRI at 3T. Magn Reson Med 76:321–328, 2016. © 2015 Wiley Periodicals, Inc.
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Affiliation(s)
- Reza Farivar
- McGill Vision Research Unit, Department of Ophthalmology, McGill University, Montreal, Quebec, Canada
| | - Filip Grigorov
- McGill Vision Research Unit, Department of Ophthalmology, McGill University, Montreal, Quebec, Canada
| | - Andre J van der Kouwe
- A.A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Charlestown, Massachusetts, USA.,Harvard Medical School, Boston, Massachusetts, USA
| | - Lawrence L Wald
- A.A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Charlestown, Massachusetts, USA.,Harvard Medical School, Boston, Massachusetts, USA.,Health Science and Technology, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA
| | - Boris Keil
- A.A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Charlestown, Massachusetts, USA.,Harvard Medical School, Boston, Massachusetts, USA
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Brown TI, Staresina BP, Wagner AD. Noninvasive functional and anatomical imaging of the human medial temporal lobe. Cold Spring Harb Perspect Biol 2015; 7:a021840. [PMID: 25780085 DOI: 10.1101/cshperspect.a021840] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
The ability to remember life's events, and to leverage memory to guide behavior, defines who we are and is critical for everyday functioning. The neural mechanisms supporting such mnemonic experiences are multiprocess and multinetwork in nature, which creates challenges for studying them in humans and animals. Advances in noninvasive neuroimaging techniques have enabled the investigation of how specific neural structures and networks contribute to human memory at its many cognitive and mechanistic levels. In this review, we discuss how functional and anatomical imaging has provided novel insights into the types of information represented in, and the computations performed by, specific medial temporal lobe (MTL) regions, and we consider how interactions between the MTL and other cortical and subcortical structures influence what we learn and remember. By leveraging imaging, researchers have markedly advanced understanding of how the MTL subserves declarative memory and enables navigation of our physical and mental worlds.
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McGugin RW, Newton AT, Gore JC, Gauthier I. Robust expertise effects in right FFA. Neuropsychologia 2014; 63:135-44. [PMID: 25192631 DOI: 10.1016/j.neuropsychologia.2014.08.029] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2014] [Revised: 07/31/2014] [Accepted: 08/25/2014] [Indexed: 11/21/2022]
Abstract
The fusiform face area (FFA) is one of several areas in occipito-temporal cortex whose activity is correlated with perceptual expertise for objects. Here, we investigate the robustness of expertise effects in FFA and other areas to a strong task manipulation that increases both perceptual and attentional demands. With high-resolution fMRI at 7T, we measured responses to images of cars, faces and a category globally visually similar to cars (sofas) in 26 subjects who varied in expertise with cars, in (a) a low load 1-back task with a single object category and (b) a high load task in which objects from two categories were rapidly alternated and attention was required to both categories. The low load condition revealed several areas more active as a function of expertise, including both posterior and anterior portions of FFA bilaterally (FFA1/FFA2, respectively). Under high load, fewer areas were positively correlated with expertise and several areas were even negatively correlated, but the expertise effect in face-selective voxels in the anterior portion of FFA (FFA2) remained robust. Finally, we found that behavioral car expertise also predicted increased responses to sofa images but no behavioral advantages in sofa discrimination, suggesting that global shape similarity to a category of expertise is enough to elicit a response in FFA and other areas sensitive to experience, even when the category itself is not of special interest. The robustness of expertise effects in right FFA2 and the expertise effects driven by visual similarity both argue against attention being the sole determinant of expertise effects in extrastriate areas.
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33
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Kim NY, Lee SM, Erlendsdottir MC, McCarthy G. Discriminable spatial patterns of activation for faces and bodies in the fusiform gyrus. Front Hum Neurosci 2014; 8:632. [PMID: 25177286 PMCID: PMC4132375 DOI: 10.3389/fnhum.2014.00632] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2014] [Accepted: 07/29/2014] [Indexed: 11/13/2022] Open
Abstract
Functional neuroimaging studies consistently report that the visual perception of faces and bodies strongly activates regions within ventral occipitotemporal cortex (VOTC) and, in particular, within the mid-lateral fusiform gyrus. One unresolved issue is the degree to which faces and bodies activate discrete or overlapping cortical regions within this region. Here, we examined VOTC activity to faces and bodies at high spatial resolution, using univariate and multivariate analysis approaches sensitive to differences in both the strength and spatial pattern of activation. Faces and bodies evoked substantially overlapping activations in the fusiform gyrus when each was compared to the control category of houses. No discrete regions of activation for faces and bodies in the fusiform gyrus survived a direct statistical comparison using standard univariate statistics. However, multi-voxel pattern analysis differentiated faces and bodies in regions where univariate analysis found no significant difference in the strength of activation. Using a whole-brain multivariate searchlight approach, we also found that extensive regions in VOTC beyond those defined as fusiform face and body areas using standard criteria where the spatial pattern of activation discriminated faces and bodies. These findings provide insights into the spatial distribution of face- and body-specific activations in VOTC and the identification of functionally specialized regions.
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Affiliation(s)
- Na Yeon Kim
- Human Neuroscience Laboratory, Department of Psychology, Yale University New Haven, CT, USA
| | - Su Mei Lee
- Human Neuroscience Laboratory, Department of Psychology, Yale University New Haven, CT, USA
| | | | - Gregory McCarthy
- Human Neuroscience Laboratory, Department of Psychology, Yale University New Haven, CT, USA
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Kang D, Choi US, Sung YW. Microscopic functional specificity can be predicted from fMRI signals in ventral visual areas. Magn Reson Imaging 2014; 32:1031-6. [PMID: 25012925 DOI: 10.1016/j.mri.2014.05.006] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2013] [Revised: 03/20/2014] [Accepted: 05/26/2014] [Indexed: 11/20/2022]
Abstract
Functional areas specialized for recognition can be activated by a non-preferred stimulus as well as a preferred stimulus. The functional magnetic resonance imaging signals detected in response to different stimuli in an area may have the same or different amplitudes. However, it is uncertain whether the responses originate from the same neuronal populations or heterogeneous ones. To address this concern, we propose a novel method that uses multi-echo echo-planar imaging sequences to evaluate changes in the transverse relaxation profile caused by stimulation. According to this method, the areas related with visual recognition, i.e. fusiform face area and parahippocampal place area, have different transverse relaxation profiles to preferred and non-preferred stimuli, which can be considered as reflecting a difference in neuronal population processing stimuli in those areas. The proposed method can be useful for probing the microscopic functional specificity of brain areas.
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35
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Grill-Spector K, Weiner KS. The functional architecture of the ventral temporal cortex and its role in categorization. Nat Rev Neurosci 2014; 15:536-48. [PMID: 24962370 DOI: 10.1038/nrn3747] [Citation(s) in RCA: 416] [Impact Index Per Article: 41.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Visual categorization is thought to occur in the human ventral temporal cortex (VTC), but how this categorization is achieved is still largely unknown. In this Review, we consider the computations and representations that are necessary for categorization and examine how the microanatomical and macroanatomical layout of the VTC might optimize them to achieve rapid and flexible visual categorization. We propose that efficient categorization is achieved by organizing representations in a nested spatial hierarchy in the VTC. This spatial hierarchy serves as a neural infrastructure for the representational hierarchy of visual information in the VTC and thereby enables flexible access to category information at several levels of abstraction.
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36
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Liu J, Li J, Feng L, Li L, Tian J, Lee K. Seeing Jesus in toast: neural and behavioral correlates of face pareidolia. Cortex 2014; 53:60-77. [PMID: 24583223 DOI: 10.1016/j.cortex.2014.01.013] [Citation(s) in RCA: 98] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2013] [Revised: 11/05/2013] [Accepted: 01/21/2014] [Indexed: 10/25/2022]
Abstract
Face pareidolia is the illusory perception of non-existent faces. The present study, for the first time, contrasted behavioral and neural responses of face pareidolia with those of letter pareidolia to explore face-specific behavioral and neural responses during illusory face processing. Participants were shown pure-noise images but were led to believe that 50% of them contained either faces or letters; they reported seeing faces or letters illusorily 34% and 38% of the time, respectively. The right fusiform face area (rFFA) showed a specific response when participants "saw" faces as opposed to letters in the pure-noise images. Behavioral responses during face pareidolia produced a classification image (CI) that resembled a face, whereas those during letter pareidolia produced a CI that was letter-like. Further, the extent to which such behavioral CIs resembled faces was directly related to the level of face-specific activations in the rFFA. This finding suggests that the rFFA plays a specific role not only in processing of real faces but also in illusory face perception, perhaps serving to facilitate the interaction between bottom-up information from the primary visual cortex and top-down signals from the prefrontal cortex (PFC). Whole brain analyses revealed a network specialized in face pareidolia, including both the frontal and occipitotemporal regions. Our findings suggest that human face processing has a strong top-down component whereby sensory input with even the slightest suggestion of a face can result in the interpretation of a face.
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Affiliation(s)
- Jiangang Liu
- School of Computer and Information Technology, Beijing Jiaotong University, Beijing, China; Dr. Eric Jackman Institute of Child Study, University of Toronto, Toronto, Canada
| | - Jun Li
- School of Life Science and Technology, Xidian University, Xi'an, China
| | - Lu Feng
- Institute of Automation Chinese Academy of Sciences, Beijing, China
| | - Ling Li
- School of Computer and Information Technology, Beijing Jiaotong University, Beijing, China
| | - Jie Tian
- School of Life Science and Technology, Xidian University, Xi'an, China; Institute of Automation Chinese Academy of Sciences, Beijing, China.
| | - Kang Lee
- Dr. Eric Jackman Institute of Child Study, University of Toronto, Toronto, Canada.
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Jiang C, Zhang L, Zou C, Long X, Liu X, Zheng H, Liao W, Diao Y. Diurnal microstructural variations in healthy adult brain revealed by diffusion tensor imaging. PLoS One 2014; 9:e84822. [PMID: 24400118 PMCID: PMC3882241 DOI: 10.1371/journal.pone.0084822] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2013] [Accepted: 11/21/2013] [Indexed: 11/26/2022] Open
Abstract
Biorhythm is a fundamental property of human physiology. Changes in the extracellular space induced by cell swelling in response to the neural activity enable the in vivo characterization of cerebral microstructure by measuring the water diffusivity using diffusion tensor imaging (DTI). To study the diurnal microstructural alterations of human brain, fifteen right-handed healthy adult subjects were recruited for DTI studies in two repeated sessions (8∶30 AM and 8∶30 PM) within a 24-hour interval. Fractional anisotropy (FA), apparent diffusion coefficient (ADC), axial (λ//) and radial diffusivity (λ⊥) were compared pixel by pixel between the sessions for each subject. Significant increased morning measurements in FA, ADC, λ// and λ⊥ were seen in a wide range of brain areas involving frontal, parietal, temporal and occipital lobes. Prominent evening dominant λ⊥ (18.58%) was detected in the right inferior temporal and ventral fusiform gyri. AM-PM variation of λ⊥ was substantially left side hemisphere dominant (p<0.05), while no hemispheric preference was observed for the same analysis for ADC (p = 0.77), λ// (p = 0.08) or FA (p = 0.25). The percentage change of ADC, λ//, λ⊥, and FA were 1.59%, 2.15%, 1.20% and 2.84%, respectively, for brain areas without diurnal diffusivity contrast. Microstructural variations may function as the substrates of the phasic neural activities in correspondence to the environment adaptation in a light-dark cycle. This research provided a baseline for researches in neuroscience, sleep medicine, psychological and psychiatric disorders, and necessitates that diurnal effect should be taken into account in following up studies using diffusion tensor quantities.
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Affiliation(s)
- Chunxiang Jiang
- Paul C. Lauterbur Research Center for Biomedical Imaging, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China
| | - Lijuan Zhang
- Paul C. Lauterbur Research Center for Biomedical Imaging, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China
- * E-mail:
| | - Chao Zou
- Paul C. Lauterbur Research Center for Biomedical Imaging, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China
| | - Xiaojing Long
- Paul C. Lauterbur Research Center for Biomedical Imaging, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China
| | - Xin Liu
- Paul C. Lauterbur Research Center for Biomedical Imaging, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China
| | - Hairong Zheng
- Paul C. Lauterbur Research Center for Biomedical Imaging, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China
| | - Weiqi Liao
- Paul C. Lauterbur Research Center for Biomedical Imaging, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China
| | - Yanjun Diao
- Paul C. Lauterbur Research Center for Biomedical Imaging, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China
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38
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Ross DA, McGugin RW, Gauthier I. Heterogeneity of FFA responses or multiplexing? Trends Cogn Sci 2013; 18:171-2. [PMID: 24360882 DOI: 10.1016/j.tics.2013.12.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2013] [Revised: 11/29/2013] [Accepted: 12/03/2013] [Indexed: 11/25/2022]
Abstract
Recent work using cluster analysis of brain activity during movies revealed distinct clusters that respond to faces and different non-face categories in the fusiform face area (FFA). Because of the limited heterogeneity observed, these results could mean that the FFA contains one population of cells capable of representing multiple categories.
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Affiliation(s)
- David A Ross
- Department of Psychology, Vanderbilt University, Nashville, TN, USA.
| | - Rankin W McGugin
- Department of Psychology, Vanderbilt University, Nashville, TN, USA
| | - Isabel Gauthier
- Department of Psychology, Vanderbilt University, Nashville, TN, USA
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Abstract
The fusiform face area (FFA) is a well-studied human brain region that shows strong activation for faces. In functional MRI studies, FFA is often assumed to be a homogeneous collection of voxels with similar visual tuning. To test this assumption, we used natural movies and a quantitative voxelwise modeling and decoding framework to estimate category tuning profiles for individual voxels within FFA. We find that the responses in most FFA voxels are strongly enhanced by faces, as reported in previous studies. However, we also find that responses of individual voxels are selectively enhanced or suppressed by a wide variety of other categories and that these broader tuning profiles differ across FFA voxels. Cluster analysis of category tuning profiles across voxels reveals three spatially segregated functional subdomains within FFA. These subdomains differ primarily in their responses for nonface categories, such as animals, vehicles, and communication verbs. Furthermore, this segregation does not depend on the statistical threshold used to define FFA from responses to functional localizers. These results suggest that voxels within FFA represent more diverse information about object and action categories than generally assumed.
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40
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Matsuo T, Kawasaki K, Kawai K, Majima K, Masuda H, Murakami H, Kunii N, Kamitani Y, Kameyama S, Saito N, Hasegawa I. Alternating zones selective to faces and written words in the human ventral occipitotemporal cortex. ACTA ACUST UNITED AC 2013; 25:1265-77. [PMID: 24285843 DOI: 10.1093/cercor/bht319] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Recognition of faces and written words is associated with category-specific brain activation in the ventral occipitotemporal cortex (vOT). However, topological and functional relationships between face-selective and word-selective vOT regions remain unclear. In this study, we collected data from patients with intractable epilepsy who underwent high-density recording of surface field potentials in the vOT. "Faces" and "letterstrings" induced outstanding category-selective responses among the 24 visual categories tested, particularly in high-γ band powers. Strikingly, within-hemispheric analysis revealed alternation of face-selective and letterstring-selective zones within the vOT. Two distinct face-selective zones located anterior and posterior portions of the mid-fusiform sulcus whereas letterstring-selective zones alternated between and outside of these 2 face-selective zones. Further, a classification analysis indicated that activity patterns of these zones mostly represent dedicated categories. Functional connectivity analysis using Granger causality indicated asymmetrically directed causal influences from face-selective to letterstring-selective regions. These results challenge the prevailing view that different categories are represented in distinct contiguous regions in the vOT.
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Affiliation(s)
- Takeshi Matsuo
- Department of Physiology, Niigata University School of Medicine, Niigata 951-8510, Japan Department of Neurosurgery, The University of Tokyo Graduate School of Medicine, Tokyo 113-8655, Japan
| | - Keisuke Kawasaki
- Department of Physiology, Niigata University School of Medicine, Niigata 951-8510, Japan
| | - Kensuke Kawai
- Department of Neurosurgery, The University of Tokyo Graduate School of Medicine, Tokyo 113-8655, Japan
| | - Kei Majima
- ATR Computational Neuroscience Laboratories, Kyoto 619-0288, Japan Graduate School of Information Science, Nara Institute of Science and Technology, 8916-5 Takayama-cho, Ikoma, Nara 630-0192, Japan
| | - Hiroshi Masuda
- Department of Neurosurgery, Nishi-Niigata Chuo National Hospital, Niigata 950-2085, Japan
| | - Hiroatsu Murakami
- Department of Neurosurgery, Nishi-Niigata Chuo National Hospital, Niigata 950-2085, Japan
| | - Naoto Kunii
- Department of Neurosurgery, The University of Tokyo Graduate School of Medicine, Tokyo 113-8655, Japan
| | - Yukiyasu Kamitani
- ATR Computational Neuroscience Laboratories, Kyoto 619-0288, Japan Graduate School of Information Science, Nara Institute of Science and Technology, 8916-5 Takayama-cho, Ikoma, Nara 630-0192, Japan
| | - Shigeki Kameyama
- Department of Neurosurgery, Nishi-Niigata Chuo National Hospital, Niigata 950-2085, Japan
| | - Nobuhito Saito
- Department of Neurosurgery, The University of Tokyo Graduate School of Medicine, Tokyo 113-8655, Japan
| | - Isao Hasegawa
- Department of Physiology, Niigata University School of Medicine, Niigata 951-8510, Japan Center for Transdisciplinary Research, Niigata University, Niigata 951-8510, Japan
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Abstract
Our understanding of the mechanisms and neural substrates underlying visual recognition has made considerable progress over the past 30 years. During this period, accumulating evidence has led many scientists to conclude that objects and faces are recognised in fundamentally distinct ways, and in fundamentally distinct cortical areas. In the psychological literature, in particular, this dissociation has led to a palpable disconnect between theories of how we process and represent the two classes of object. This paper follows a trend in part of the recognition literature to try to reconcile what we know about these two forms of recognition by considering the effects of learning. Taking a widely accepted, self-organizing model of object recognition, this paper explains how such a system is affected by repeated exposure to specific stimulus classes. In so doing, it explains how many aspects of recognition generally regarded as unusual to faces (holistic processing, configural processing, sensitivity to inversion, the other-race effect, the prototype effect, etc.) are emergent properties of category-specific learning within such a system. Overall, the paper describes how a single model of recognition learning can and does produce the seemingly very different types of representation associated with faces and objects.
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Affiliation(s)
- Guy Wallis
- Centre for Sensorimotor Neuroscience, School of Human Movement Studies, University of QueenslandQLD, Australia
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42
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Chong SC, Jo S, Park KM, Joo EY, Lee MJ, Hong SC, Hong SB. Interaction between the electrical stimulation of a face-selective area and the perception of face stimuli. Neuroimage 2013; 77:70-6. [DOI: 10.1016/j.neuroimage.2013.01.074] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2012] [Revised: 12/18/2012] [Accepted: 01/26/2013] [Indexed: 11/26/2022] Open
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Rodriguez Merzagora A, Coffey TJ, Sperling MR, Sharan A, Litt B, Baltuch G, Jacobs J. Repeated stimuli elicit diminished high-gamma electrocorticographic responses. Neuroimage 2013; 85 Pt 2:844-52. [PMID: 23867555 DOI: 10.1016/j.neuroimage.2013.07.006] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2013] [Revised: 06/25/2013] [Accepted: 07/02/2013] [Indexed: 10/26/2022] Open
Abstract
In the phenomenon of repetition suppression (RS), when a person views a stimulus, the neural activity involved in processing that item is relatively diminished if that stimulus had been previously viewed. Previous noninvasive imaging studies mapped the prevalence of RS for different stimulus types to identify brain regions involved in representing a range of cognitive information. However, these noninvasive findings are challenging to interpret because they do not provide information on how RS relates to the brain's electrophysiological activity. We examined the electrophysiological basis of RS directly using brain recordings from implanted electrocorticographic (ECoG) electrodes in neurosurgical patients. Patients performed a memory task during ECoG recording and we identified high-gamma signals (65-128 Hz) that distinguished the neuronal representation of specific memory items. We then compared the neural representation of each item between novel and repeated viewings. This revealed the presence of RS, in which the neuronal representation of a repeated item had a significantly decreased amplitude and duration compared with novel stimuli. Furthermore, the magnitude of RS was greatest for the stimuli that initially elicited the largest activation at each site. These results have implications for understanding the neural basis of RS and human memory by showing that individual cortical sites exhibit the largest RS for the stimuli that they most actively represent.
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Affiliation(s)
- Anna Rodriguez Merzagora
- School of Biomedical Engineering, Science & Health Systems, Drexel University, Philadelphia, PA 19104, USA
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Segal E, Petrides M. Functional activation during reading in relation to the sulci of the angular gyrus region. Eur J Neurosci 2013; 38:2793-801. [PMID: 23773118 DOI: 10.1111/ejn.12277] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2013] [Accepted: 05/13/2013] [Indexed: 11/27/2022]
Abstract
Neurological studies suggest that the angular gyrus region of the inferior parietal lobule may be critical for reading. However, unambiguous demonstration of angular gyrus involvement from lesion and functional neuroimaging studies is lacking, partly because of the absence of detailed morphological descriptions of this region. On the basis of our recent anatomical examination of this region and a tightly controlled functional magnetic resonance imaging paradigm, the present investigation demonstrated reading-related activity in the region of the angular gyrus that lies between the central and posterior branches of the caudal superior temporal sulcus, namely cytoarchitectonic area PG. Analysis of functional connectivity showed increased functional coupling during reading of area PG with the language areas of Broca and Wernicke, and a region previously identified as the visual word form area. Thus, the parietal reading area has been precisely localized, and its interactions with other cortical areas during reading have been demonstrated.
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Affiliation(s)
- Emily Segal
- McGill University, Montreal, Quebec, Canada.
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45
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Axelrod V, Yovel G. The challenge of localizing the anterior temporal face area: a possible solution. Neuroimage 2013; 81:371-380. [PMID: 23684864 DOI: 10.1016/j.neuroimage.2013.05.015] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2013] [Revised: 05/03/2013] [Accepted: 05/08/2013] [Indexed: 10/26/2022] Open
Abstract
Humans recognize faces exceptionally well. However, the neural correlates of face recognition are still elusive. Accumulated evidence in recent years suggests that the anterior temporal lobe (ATL), in particular face-selective region in the ATL, is a probable locus of face recognition. Unfortunately, functional MRI (fMRI) studies encounter severe signal drop-out in the ventral ATL, where that ATL face area resides. Consequently, all previous studies localized this region in no more than half of the subjects and its volume was relatively small. Thus, a systematic exploration of the properties of the ATL face area is scarce. In the current high-resolution fMRI study we used coronal slice orientation, which permitted us to localize the ATL face area in all the subjects. Furthermore, the volume of the area was much larger than was reported in previous studies. Direct within subjects comparison with data collected with the commonly used axial slice orientation confirmed that the advantage of the coronal slice orientation in revealing a reliable and larger face-selective area in the ATL. Finally, by displaying the face-selective activations resultant from coronal and axial scanning together, we demonstrate an organization principle of a chain of face-selective regions along the posterior-anterior axis in the ventral temporal lobe that is highly reproducible across all subjects. By using the procedure proposed here, a significant progress can be made in studying the neural correlates of face recognition.
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Affiliation(s)
- Vadim Axelrod
- School of Psychological Sciences, Tel Aviv University, Tel Aviv, Israel.
| | - Galit Yovel
- School of Psychological Sciences, Tel Aviv University, Tel Aviv, Israel; Sagol School of Neuroscience, Tel Aviv University, Tel Aviv, Israel
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Behrmann M, Plaut DC. Distributed circuits, not circumscribed centers, mediate visual recognition. Trends Cogn Sci 2013; 17:210-9. [PMID: 23608364 DOI: 10.1016/j.tics.2013.03.007] [Citation(s) in RCA: 202] [Impact Index Per Article: 18.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2013] [Revised: 03/29/2013] [Accepted: 03/29/2013] [Indexed: 11/23/2022]
Abstract
Increasingly, the neural mechanisms that support visual cognition are being conceptualized as a distributed but integrated system, as opposed to a set of individual, specialized regions that each subserve a particular visual behavior. Consequently, there is an emerging emphasis on characterizing the functional, structural,and computational properties of these broad networks [corrected]. We present a novel theoretical perspective, which elucidates the developmental emergence, computational properties, and vulnerabilities of integrated circuits using face and word recognition as model domains. Additionally, we suggest that, rather than being disparate and independent, these neural circuits are overlapping and subject to the same computational constraints. Specifically, we argue that both word and face recognition rely on fine-grained visual representations but, by virtue of pressure to couple visual and language areas and to keep connection length short, the left hemisphere becomes more finely tuned for word recognition and, consequently, the right hemisphere becomes more finely tuned for face recognition. Thus, both hemispheres ultimately participate in both forms of visual recognition, but their respective contributions are asymmetrically weighted.
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Avidan G, Tanzer M, Hadj-Bouziane F, Liu N, Ungerleider LG, Behrmann M. Selective dissociation between core and extended regions of the face processing network in congenital prosopagnosia. ACTA ACUST UNITED AC 2013; 24:1565-78. [PMID: 23377287 DOI: 10.1093/cercor/bht007] [Citation(s) in RCA: 139] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
There is growing consensus that accurate and efficient face recognition is mediated by a neural circuit composed of a posterior "core" and an anterior "extended" set of regions. Here, we characterize the distributed face network in human individuals with congenital prosopagnosia (CP)-a lifelong impairment in face processing-relative to that of matched controls. Using functional magnetic resonance imaging, we first uncover largely normal activation patterns in the posterior core face patches in CP. We also document normal activity of the amygdala (emotion processing) as well as normal or even enhanced functional connectivity between the amygdala and the core regions. Critically, in the same individuals, activation of the anterior temporal cortex (identity processing) is reduced and connectivity between this region and the posterior core regions is disrupted. The dissociation between the neural profiles of the anterior temporal lobe and amygdala was evident both during a task-related face scan and during a resting state scan, in the absence of visual stimulation. Taken together, these findings elucidate selective disruptions in neural circuitry in CP and offer an explanation for the known differential difficulty in identity versus emotional expression recognition in many individuals with CP.
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Affiliation(s)
- Galia Avidan
- Department of Psychology, Ben-Gurion University of the Negev, Beer Sheva 84105, Israel
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Behrmann M, Plaut DC. Bilateral hemispheric processing of words and faces: evidence from word impairments in prosopagnosia and face impairments in pure alexia. ACTA ACUST UNITED AC 2012; 24:1102-18. [PMID: 23250954 DOI: 10.1093/cercor/bhs390] [Citation(s) in RCA: 94] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
Considerable research has supported the view that faces and words are subserved by independent neural mechanisms located in the ventral visual cortex in opposite hemispheres. On this view, right hemisphere ventral lesions that impair face recognition (prosopagnosia) should leave word recognition unaffected, and left hemisphere ventral lesions that impair word recognition (pure alexia) should leave face recognition unaffected. The current study shows that neither of these predictions was upheld. A series of experiments characterizing speed and accuracy of word and face recognition were conducted in 7 patients (4 pure alexic, 3 prosopagnosic) and matched controls. Prosopagnosic patients revealed mild but reliable word recognition deficits, and pure alexic patients demonstrated mild but reliable face recognition deficits. The apparent comingling of face and word mechanisms is unexpected from a domain-specific perspective, but follows naturally as a consequence of an interactive, learning-based account in which neural processes for both faces and words are the result of an optimization procedure embodying specific computational principles and constraints.
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Affiliation(s)
- Marlene Behrmann
- Department of Psychology, Center for the Neural Basis of Cognition, Carnegie Mellon University, Pittsburgh, PA 15213-3890, USA
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McGugin RW, Gatenby JC, Gore JC, Gauthier I. High-resolution imaging of expertise reveals reliable object selectivity in the fusiform face area related to perceptual performance. Proc Natl Acad Sci U S A 2012; 109:17063-8. [PMID: 23027970 DOI: 10.1073/pnas.1116333109] [Citation(s) in RCA: 135] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The fusiform face area (FFA) is a region of human cortex that responds selectively to faces, but whether it supports a more general function relevant for perceptual expertise is debated. Although both faces and objects of expertise engage many brain areas, the FFA remains the focus of the strongest modular claims and the clearest predictions about expertise. Functional MRI studies at standard-resolution (SR-fMRI) have found responses in the FFA for nonface objects of expertise, but high-resolution fMRI (HR-fMRI) in the FFA [Grill-Spector K, et al. (2006) Nat Neurosci 9:1177-1185] and neurophysiology in face patches in the monkey brain [Tsao DY, et al. (2006) Science 311:670-674] reveal no reliable selectivity for objects. It is thus possible that FFA responses to objects with SR-fMRI are a result of spatial blurring of responses from nonface-selective areas, potentially driven by attention to objects of expertise. Using HR-fMRI in two experiments, we provide evidence of reliable responses to cars in the FFA that correlate with behavioral car expertise. Effects of expertise in the FFA for nonface objects cannot be attributed to spatial blurring beyond the scale at which modular claims have been made, and within the lateral fusiform gyrus, they are restricted to a small area (200 mm(2) on the right and 50 mm(2) on the left) centered on the peak of face selectivity. Experience with a category may be sufficient to explain the spatially clustered face selectivity observed in this region.
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