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Murphy E, Rollo PS, Segaert K, Hagoort P, Tandon N. Multiple dimensions of syntactic structure are resolved earliest in posterior temporal cortex. Prog Neurobiol 2024; 241:102669. [PMID: 39332803 DOI: 10.1016/j.pneurobio.2024.102669] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2024] [Revised: 08/08/2024] [Accepted: 09/24/2024] [Indexed: 09/29/2024]
Abstract
How we combine minimal linguistic units into larger structures remains an unresolved topic in neuroscience. Language processing involves the abstract construction of 'vertical' and 'horizontal' information simultaneously (e.g., phrase structure, morphological agreement), but previous paradigms have been constrained in isolating only one type of composition and have utilized poor spatiotemporal resolution. Using intracranial recordings, we report multiple experiments designed to separate phrase structure from morphosyntactic agreement. Epilepsy patients (n = 10) were presented with auditory two-word phrases grouped into pseudoword-verb ('trab run') and pronoun-verb either with or without Person agreement ('they run' vs. 'they runs'). Phrase composition and Person violations both resulted in significant increases in broadband high gamma activity approximately 300ms after verb onset in posterior middle temporal gyrus (pMTG) and posterior superior temporal sulcus (pSTS), followed by inferior frontal cortex (IFC) at 500ms. While sites sensitive to only morphosyntactic violations were distributed, those sensitive to both composition types were generally confined to pSTS/pMTG and IFC. These results indicate that posterior temporal cortex shows the earliest sensitivity for hierarchical linguistic structure across multiple dimensions, providing neural resources for distinct windows of composition. This region is comprised of sparsely interwoven heterogeneous constituents that afford cortical search spaces for dissociable syntactic relations.
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Affiliation(s)
- Elliot Murphy
- Vivian L. Smith Department of Neurosurgery, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, TX 77030; Texas Institute for Restorative Neurotechnologies, University of Texas Health Science Center at Houston, Houston, TX 77030.
| | - Patrick S Rollo
- Vivian L. Smith Department of Neurosurgery, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, TX 77030; Texas Institute for Restorative Neurotechnologies, University of Texas Health Science Center at Houston, Houston, TX 77030
| | - Katrien Segaert
- School of Psychology & Centre for Human Brain Health, University of Birmingham, Birmingham, UK, B15 2TT; Max Planck Institute for Psycholinguistics, Nijmegen, The Netherlands, 6525 XD Nijmegen
| | - Peter Hagoort
- Max Planck Institute for Psycholinguistics, Nijmegen, The Netherlands, 6525 XD Nijmegen; Donders Institute for Brain, Cognition and Behaviour, Nijmegen, The Netherlands, 6525 HR Nijmegen
| | - Nitin Tandon
- Vivian L. Smith Department of Neurosurgery, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, TX 77030; Texas Institute for Restorative Neurotechnologies, University of Texas Health Science Center at Houston, Houston, TX 77030; Memorial Hermann Hospital, Texas Medical Center, Houston, TX 77030.
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Pigorini A, Avanzini P, Barborica A, Bénar CG, David O, Farisco M, Keller CJ, Manfridi A, Mikulan E, Paulk AC, Roehri N, Subramanian A, Vulliémoz S, Zelmann R. Simultaneous invasive and non-invasive recordings in humans: A novel Rosetta stone for deciphering brain activity. J Neurosci Methods 2024; 408:110160. [PMID: 38734149 DOI: 10.1016/j.jneumeth.2024.110160] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2023] [Revised: 04/10/2024] [Accepted: 05/01/2024] [Indexed: 05/13/2024]
Abstract
Simultaneous noninvasive and invasive electrophysiological recordings provide a unique opportunity to achieve a comprehensive understanding of human brain activity, much like a Rosetta stone for human neuroscience. In this review we focus on the increasingly-used powerful combination of intracranial electroencephalography (iEEG) with scalp electroencephalography (EEG) or magnetoencephalography (MEG). We first provide practical insight on how to achieve these technically challenging recordings. We then provide examples from clinical research on how simultaneous recordings are advancing our understanding of epilepsy. This is followed by the illustration of how human neuroscience and methodological advances could benefit from these simultaneous recordings. We conclude with a call for open data sharing and collaboration, while ensuring neuroethical approaches and argue that only with a true collaborative approach the promises of simultaneous recordings will be fulfilled.
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Affiliation(s)
- Andrea Pigorini
- Department of Biomedical, Surgical and Dental Sciences, Università degli Studi di Milano, Milan, Italy; UOC Maxillo-facial Surgery and dentistry, Fondazione IRCCS Cà Granda, Ospedale Maggiore Policlinico, Milan, Italy.
| | - Pietro Avanzini
- Institute of Neuroscience, Consiglio Nazionale delle Ricerche, Parma, Italy
| | | | - Christian-G Bénar
- Aix Marseille Univ, Inserm, U1106, INS, Institut de Neurosciences des Systèmes, Marseille, France
| | - Olivier David
- Aix Marseille Univ, Inserm, U1106, INS, Institut de Neurosciences des Systèmes, Marseille, France
| | - Michele Farisco
- Centre for Research Ethics and Bioethics, Department of Public Health and Caring Sciences, Uppsala University, P.O. Box 256, Uppsala, SE 751 05, Sweden; Science and Society Unit Biogem, Biology and Molecular Genetics Institute, Via Camporeale snc, Ariano Irpino, AV 83031, Italy
| | - Corey J Keller
- Department of Psychiatry & Behavioral Sciences, Stanford University Medical Center, Stanford, CA 94305, USA; Wu Tsai Neurosciences Institute, Stanford University Medical Center, Stanford, CA 94305, USA; Veterans Affairs Palo Alto Healthcare System, and the Sierra Pacific Mental Illness, Research, Education, and Clinical Center (MIRECC), Palo Alto, CA 94394, USA
| | - Alfredo Manfridi
- Department of Pathophysiology and Transplantation, Università degli Studi di Milano, Milan, Italy
| | - Ezequiel Mikulan
- Department of Health Sciences, Università degli Studi di Milano, Milan, Italy
| | - Angelique C Paulk
- Department of Neurology and Center for Neurotechnology and Neurorecovery, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
| | - Nicolas Roehri
- EEG and Epilepsy Unit, Dpt of Clinical Neurosciences, Geneva University Hospitals and University of Geneva, Switzerland
| | - Ajay Subramanian
- Department of Psychiatry & Behavioral Sciences, Stanford University Medical Center, Stanford, CA 94305, USA; Wu Tsai Neurosciences Institute, Stanford University Medical Center, Stanford, CA 94305, USA; Veterans Affairs Palo Alto Healthcare System, and the Sierra Pacific Mental Illness, Research, Education, and Clinical Center (MIRECC), Palo Alto, CA 94394, USA
| | - Serge Vulliémoz
- EEG and Epilepsy Unit, Dpt of Clinical Neurosciences, Geneva University Hospitals and University of Geneva, Switzerland
| | - Rina Zelmann
- Department of Neurology and Center for Neurotechnology and Neurorecovery, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA.
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3
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Murphy E, Forseth KJ, Donos C, Snyder KM, Rollo PS, Tandon N. The spatiotemporal dynamics of semantic integration in the human brain. Nat Commun 2023; 14:6336. [PMID: 37875526 PMCID: PMC10598228 DOI: 10.1038/s41467-023-42087-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2022] [Accepted: 09/28/2023] [Indexed: 10/26/2023] Open
Abstract
Language depends critically on the integration of lexical information across multiple words to derive semantic concepts. Limitations of spatiotemporal resolution have previously rendered it difficult to isolate processes involved in semantic integration. We utilized intracranial recordings in epilepsy patients (n = 58) who read written word definitions. Descriptions were either referential or non-referential to a common object. Semantically referential sentences enabled high frequency broadband gamma activation (70-150 Hz) of the inferior frontal sulcus (IFS), medial parietal cortex, orbitofrontal cortex (OFC) and medial temporal lobe in the left, language-dominant hemisphere. IFS, OFC and posterior middle temporal gyrus activity was modulated by the semantic coherence of non-referential sentences, exposing semantic effects that were independent of task-based referential status. Components of this network, alongside posterior superior temporal sulcus, were engaged for referential sentences that did not clearly reduce the lexical search space by the final word. These results indicate the existence of complementary cortical mosaics for semantic integration in posterior temporal and inferior frontal cortex.
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Affiliation(s)
- Elliot Murphy
- Vivian L. Smith Department of Neurosurgery, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, TX, 77030, USA.
- Texas Institute for Restorative Neurotechnologies, University of Texas Health Science Center at Houston, Houston, TX, 77030, USA.
| | - Kiefer J Forseth
- Vivian L. Smith Department of Neurosurgery, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, TX, 77030, USA
- Texas Institute for Restorative Neurotechnologies, University of Texas Health Science Center at Houston, Houston, TX, 77030, USA
| | - Cristian Donos
- Faculty of Physics, University of Bucharest, Măgurele, 077125, Bucharest, Romania
| | - Kathryn M Snyder
- Vivian L. Smith Department of Neurosurgery, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, TX, 77030, USA
- Texas Institute for Restorative Neurotechnologies, University of Texas Health Science Center at Houston, Houston, TX, 77030, USA
| | - Patrick S Rollo
- Vivian L. Smith Department of Neurosurgery, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, TX, 77030, USA
- Texas Institute for Restorative Neurotechnologies, University of Texas Health Science Center at Houston, Houston, TX, 77030, USA
| | - Nitin Tandon
- Vivian L. Smith Department of Neurosurgery, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, TX, 77030, USA.
- Texas Institute for Restorative Neurotechnologies, University of Texas Health Science Center at Houston, Houston, TX, 77030, USA.
- Memorial Hermann Hospital, Texas Medical Center, Houston, TX, 77030, USA.
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Woolnough O, Donos C, Murphy E, Rollo PS, Roccaforte ZJ, Dehaene S, Tandon N. Spatiotemporally distributed frontotemporal networks for sentence reading. Proc Natl Acad Sci U S A 2023; 120:e2300252120. [PMID: 37068244 PMCID: PMC10151604 DOI: 10.1073/pnas.2300252120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2023] [Accepted: 03/14/2023] [Indexed: 04/19/2023] Open
Abstract
Reading a sentence entails integrating the meanings of individual words to infer more complex, higher-order meaning. This highly rapid and complex human behavior is known to engage the inferior frontal gyrus (IFG) and middle temporal gyrus (MTG) in the language-dominant hemisphere, yet whether there are distinct contributions of these regions to sentence reading is still unclear. To probe these neural spatiotemporal dynamics, we used direct intracranial recordings to measure neural activity while reading sentences, meaning-deficient Jabberwocky sentences, and lists of words or pseudowords. We isolated two functionally and spatiotemporally distinct frontotemporal networks, each sensitive to distinct aspects of word and sentence composition. The first distributed network engages the IFG and MTG, with IFG activity preceding MTG. Activity in this network ramps up over the duration of a sentence and is reduced or absent during Jabberwocky and word lists, implying its role in the derivation of sentence-level meaning. The second network engages the superior temporal gyrus and the IFG, with temporal responses leading those in frontal lobe, and shows greater activation for each word in a list than those in sentences, suggesting that sentential context enables greater efficiency in the lexical and/or phonological processing of individual words. These adjacent, yet spatiotemporally dissociable neural mechanisms for word- and sentence-level processes shed light on the richly layered semantic networks that enable us to fluently read. These results imply distributed, dynamic computation across the frontotemporal language network rather than a clear dichotomy between the contributions of frontal and temporal structures.
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Affiliation(s)
- Oscar Woolnough
- Vivian L. Smith Department of Neurosurgery, McGovern Medical School at UT Health Houston, Houston, TX77030
- Texas Institute for Restorative Neurotechnologies, University of Texas Health Science Center at Houston, Houston, TX77030
| | - Cristian Donos
- Vivian L. Smith Department of Neurosurgery, McGovern Medical School at UT Health Houston, Houston, TX77030
- Faculty of Physics, University of Bucharest, 050663Bucharest, Romania
| | - Elliot Murphy
- Vivian L. Smith Department of Neurosurgery, McGovern Medical School at UT Health Houston, Houston, TX77030
- Texas Institute for Restorative Neurotechnologies, University of Texas Health Science Center at Houston, Houston, TX77030
| | - Patrick S. Rollo
- Vivian L. Smith Department of Neurosurgery, McGovern Medical School at UT Health Houston, Houston, TX77030
- Texas Institute for Restorative Neurotechnologies, University of Texas Health Science Center at Houston, Houston, TX77030
| | - Zachary J. Roccaforte
- Vivian L. Smith Department of Neurosurgery, McGovern Medical School at UT Health Houston, Houston, TX77030
- Texas Institute for Restorative Neurotechnologies, University of Texas Health Science Center at Houston, Houston, TX77030
| | - Stanislas Dehaene
- Cognitive Neuroimaging Unit, Université Paris-Saclay, INSERM, CEA, NeuroSpin Center, 91191Gif-sur-Yvette, France
- Collège de France, 75005Paris, France
| | - Nitin Tandon
- Vivian L. Smith Department of Neurosurgery, McGovern Medical School at UT Health Houston, Houston, TX77030
- Texas Institute for Restorative Neurotechnologies, University of Texas Health Science Center at Houston, Houston, TX77030
- Memorial Hermann Hospital, Texas Medical Center, Houston, TX77030
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5
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Woolnough O, Donos C, Curtis A, Rollo PS, Roccaforte ZJ, Dehaene S, Fischer-Baum S, Tandon N. A Spatiotemporal Map of Reading Aloud. J Neurosci 2022; 42:5438-5450. [PMID: 35641189 PMCID: PMC9270918 DOI: 10.1523/jneurosci.2324-21.2022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2021] [Revised: 05/01/2022] [Accepted: 05/07/2022] [Indexed: 01/09/2023] Open
Abstract
Reading words aloud is a fundamental aspect of literacy. The rapid rate at which multiple distributed neural substrates are engaged in this process can only be probed via techniques with high spatiotemporal resolution. We probed this with direct intracranial recordings covering most of the left hemisphere in 46 humans (26 male, 20 female) as they read aloud regular, exception and pseudo-words. We used this to create a spatiotemporal map of word processing and to derive how broadband γ activity varies with multiple word attributes critical to reading speed: lexicality, word frequency, and orthographic neighborhood. We found that lexicality is encoded earliest in mid-fusiform (mFus) cortex, and precentral sulcus, and is represented reliably enough to allow single-trial lexicality decoding. Word frequency is first represented in mFus and later in the inferior frontal gyrus (IFG) and inferior parietal sulcus (IPS), while orthographic neighborhood sensitivity resides solely in IPS. We thus isolate the neural correlates of the distributed reading network involving mFus, IFG, IPS, precentral sulcus, and motor cortex and provide direct evidence for parallel processes via the lexical route from mFus to IFG, and the sublexical route from IPS and precentral sulcus to anterior IFG.SIGNIFICANCE STATEMENT Reading aloud depends on multiple complex cerebral computations: mapping from a written letter string on a page to a sequence of spoken sound representations. Here, we used direct intracranial recordings in a large cohort while they read aloud known and novel words, to track, across space and time, the progression of neural representations of behaviorally relevant factors that govern reading speed. We find, concordant with cognitive models of reading, that known and novel words are differentially processed through a lexical route, sensitive to frequency of occurrence of known words in natural language, and a sublexical route, performing letter-by-letter construction of novel words.
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Affiliation(s)
- Oscar Woolnough
- Vivian L. Smith Department of Neurosurgery, McGovern Medical School at UT Health Houston, Houston, Texas 77030
- Texas Institute for Restorative Neurotechnologies, University of Texas Health Science Center at Houston, Houston, Texas 77030
| | - Cristian Donos
- Vivian L. Smith Department of Neurosurgery, McGovern Medical School at UT Health Houston, Houston, Texas 77030
- Faculty of Physics, University of Bucharest, Bucharest, 050663, Romania
| | - Aidan Curtis
- Vivian L. Smith Department of Neurosurgery, McGovern Medical School at UT Health Houston, Houston, Texas 77030
| | - Patrick S Rollo
- Vivian L. Smith Department of Neurosurgery, McGovern Medical School at UT Health Houston, Houston, Texas 77030
- Texas Institute for Restorative Neurotechnologies, University of Texas Health Science Center at Houston, Houston, Texas 77030
| | - Zachary J Roccaforte
- Vivian L. Smith Department of Neurosurgery, McGovern Medical School at UT Health Houston, Houston, Texas 77030
- Texas Institute for Restorative Neurotechnologies, University of Texas Health Science Center at Houston, Houston, Texas 77030
| | - Stanislas Dehaene
- Cognitive Neuroimaging Unit CEA, Institut National de la Santé et de la Recherche Médicale, NeuroSpin Center, Université Paris-Sud and Université Paris-Saclay, Gif-sur-Yvette, 91191, France
- Collège de France, Paris, 75005, France
| | - Simon Fischer-Baum
- Department of Psychological Sciences, Rice University, Houston, Texas 77005
| | - Nitin Tandon
- Vivian L. Smith Department of Neurosurgery, McGovern Medical School at UT Health Houston, Houston, Texas 77030
- Texas Institute for Restorative Neurotechnologies, University of Texas Health Science Center at Houston, Houston, Texas 77030
- Memorial Hermann Hospital, Texas Medical Center, Houston, Texas 77030
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Murphy E, Woolnough O, Rollo PS, Roccaforte ZJ, Segaert K, Hagoort P, Tandon N. Minimal Phrase Composition Revealed by Intracranial Recordings. J Neurosci 2022; 42:3216-3227. [PMID: 35232761 PMCID: PMC8994536 DOI: 10.1523/jneurosci.1575-21.2022] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2021] [Revised: 01/11/2022] [Accepted: 01/18/2022] [Indexed: 11/21/2022] Open
Abstract
The ability to comprehend phrases is an essential integrative property of the brain. Here, we evaluate the neural processes that enable the transition from single-word processing to a minimal compositional scheme. Previous research has reported conflicting timing effects of composition, and disagreement persists with respect to inferior frontal and posterior temporal contributions. To address these issues, 19 patients (10 male, 9 female) implanted with penetrating depth or surface subdural intracranial electrodes, heard auditory recordings of adjective-noun, pseudoword-noun, and adjective-pseudoword phrases and judged whether the phrase matched a picture. Stimulus-dependent alterations in broadband gamma activity, low-frequency power, and phase-locking values across the language-dominant left hemisphere were derived. This revealed a mosaic located on the lower bank of the posterior superior temporal sulcus (pSTS), in which closely neighboring cortical sites displayed exclusive sensitivity to either lexicality or phrase structure, but not both. Distinct timings were found for effects of phrase composition (210-300 ms) and pseudoword processing (∼300-700 ms), and these were localized to neighboring electrodes in pSTS. The pars triangularis and temporal pole encoded anticipation of composition in broadband low frequencies, and both regions exhibited greater functional connectivity with pSTS during phrase composition. Our results suggest that the pSTS is a highly specialized region composed of sparsely interwoven heterogeneous constituents that encodes both lower and higher level linguistic features. This hub in pSTS for minimal phrase processing may form the neural basis for the human-specific computational capacity for forming hierarchically organized linguistic structures.SIGNIFICANCE STATEMENT Linguists have claimed that the integration of multiple words into a phrase demands a computational procedure distinct from single-word processing. Here, we provide intracranial recordings from a large patient cohort, with high spatiotemporal resolution, to track the cortical dynamics of phrase composition. Epileptic patients volunteered to participate in a task in which they listened to phrases (red boat), word-pseudoword or pseudoword-word pairs (e.g., red fulg). At the onset of the second word in phrases, greater broadband high gamma activity was found in posterior superior temporal sulcus in electrodes that exclusively indexed phrasal meaning and not lexical meaning. These results provide direct, high-resolution signatures of minimal phrase composition in humans, a potentially species-specific computational capacity.
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Affiliation(s)
- Elliot Murphy
- Vivian L. Smith Department of Neurosurgery, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, Texas 77030
- Texas Institute for Restorative Neurotechnologies, University of Texas Health Science Center at Houston, Houston, Texas 77030
| | - Oscar Woolnough
- Vivian L. Smith Department of Neurosurgery, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, Texas 77030
- Texas Institute for Restorative Neurotechnologies, University of Texas Health Science Center at Houston, Houston, Texas 77030
| | - Patrick S Rollo
- Vivian L. Smith Department of Neurosurgery, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, Texas 77030
- Texas Institute for Restorative Neurotechnologies, University of Texas Health Science Center at Houston, Houston, Texas 77030
| | - Zachary J Roccaforte
- Vivian L. Smith Department of Neurosurgery, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, Texas 77030
| | - Katrien Segaert
- School of Psychology and Centre for Human Brain Health, University of Birmingham, Birmingham B15 2TT, United Kingdom
- Max Planck Institute for Psycholinguistics, Nijmegen, 6525 XD Nijmegen, The Netherlands
| | - Peter Hagoort
- Max Planck Institute for Psycholinguistics, Nijmegen, 6525 XD Nijmegen, The Netherlands
- Donders Institute for Brain, Cognition and Behaviour, Nijmegen, 6525 HR Nijmegen, The Netherlands
| | - Nitin Tandon
- Vivian L. Smith Department of Neurosurgery, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, Texas 77030
- Texas Institute for Restorative Neurotechnologies, University of Texas Health Science Center at Houston, Houston, Texas 77030
- Memorial Hermann Hospital, Texas Medical Center, Houston, Texas 77030
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7
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McCarty MJ, Woolnough O, Mosher JC, Seymour J, Tandon N. The Listening Zone of Human Electrocorticographic Field Potential Recordings. eNeuro 2022; 9:ENEURO.0492-21.2022. [PMID: 35410871 PMCID: PMC9034754 DOI: 10.1523/eneuro.0492-21.2022] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2021] [Revised: 02/09/2022] [Accepted: 03/04/2022] [Indexed: 01/05/2023] Open
Abstract
Intracranial electroencephalographic (icEEG) recordings provide invaluable insights into neural dynamics in humans because of their unmatched spatiotemporal resolution. Yet, such recordings reflect the combined activity of multiple underlying generators, confounding the ability to resolve spatially distinct neural sources. To empirically quantify the listening zone of icEEG recordings, we computed correlations between signals as a function of distance (full width at half maximum; FWHM) between 8752 recording sites in 71 patients (33 female) implanted with either subdural electrodes (SDEs), stereo-encephalography electrodes (sEEG), or high-density sEEG electrodes. As expected, for both SDEs and sEEGs, higher frequency signals exhibited a sharper fall off relative to lower frequency signals. For broadband high γ (BHG) activity, the mean FWHM of SDEs (6.6 ± 2.5 mm) and sEEGs in gray matter (7.14 ± 1.7 mm) was not significantly different; however, FWHM for low frequencies recorded by sEEGs was 2.45 mm smaller than SDEs. White matter sEEGs showed much lower power for frequencies 17-200 Hz (q < 0.01) and a much broader decay (11.3 ± 3.2 mm) than gray matter electrodes (7.14 ± 1.7 mm). The use of a bipolar referencing scheme significantly lowered FWHM for sEEGs, relative to a white matter reference or a common average reference (CAR). These results outline the influence of array design, spectral bands, and referencing schema on local field potential recordings and source localization in icEEG recordings in humans. The metrics we derive have immediate relevance to the analysis and interpretation of both cognitive and epileptic data.
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Affiliation(s)
- Meredith J McCarty
- Vivian L. Smith Department of Neurosurgery, McGovern Medical School, University of Texas Health Houston, Houston, TX 77030
- Texas Institute for Restorative Neurotechnologies, University of Texas Health Science Center at Houston, Houston, TX 77030
| | - Oscar Woolnough
- Vivian L. Smith Department of Neurosurgery, McGovern Medical School, University of Texas Health Houston, Houston, TX 77030
- Texas Institute for Restorative Neurotechnologies, University of Texas Health Science Center at Houston, Houston, TX 77030
| | - John C Mosher
- Texas Institute for Restorative Neurotechnologies, University of Texas Health Science Center at Houston, Houston, TX 77030
| | - John Seymour
- Vivian L. Smith Department of Neurosurgery, McGovern Medical School, University of Texas Health Houston, Houston, TX 77030
- Texas Institute for Restorative Neurotechnologies, University of Texas Health Science Center at Houston, Houston, TX 77030
| | - Nitin Tandon
- Vivian L. Smith Department of Neurosurgery, McGovern Medical School, University of Texas Health Houston, Houston, TX 77030
- Texas Institute for Restorative Neurotechnologies, University of Texas Health Science Center at Houston, Houston, TX 77030
- Memorial Hermann Hospital, Texas Medical Center, Houston, TX 77030
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Woolnough O, Kadipasaoglu CM, Conner CR, Forseth KJ, Rollo PS, Rollo MJ, Baboyan VG, Tandon N. Dataset of human intracranial recordings during famous landmark identification. Sci Data 2022; 9:28. [PMID: 35102154 PMCID: PMC8803828 DOI: 10.1038/s41597-022-01125-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2021] [Accepted: 11/03/2021] [Indexed: 11/18/2022] Open
Abstract
For most people, recalling information about familiar items in a visual scene is an effortless task, but it is one that depends on coordinated interactions of multiple, distributed neural components. We leveraged the high spatiotemporal resolution of direct intracranial recordings to better delineate the network dynamics underpinning visual scene recognition. We present a dataset of recordings from a large cohort of humans while they identified images of famous landmarks (50 individuals, 52 recording sessions, 6,775 electrodes, 6,541 trials). This dataset contains local field potential recordings derived from subdural and penetrating electrodes covering broad areas of cortex across both hemispheres. We provide this pre-processed data with behavioural metrics (correct/incorrect, response times) and electrode localisation in a population-normalised cortical surface space. This rich dataset will allow further investigation into the spatiotemporal progression of multiple neural processes underlying visual processing, scene recognition and cued memory recall.
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Affiliation(s)
- Oscar Woolnough
- Vivian L. Smith Department of Neurosurgery, McGovern Medical School at UT Health Houston, Houston, TX, 77030, United States of America
- Texas Institute for Restorative Neurotechnologies, University of Texas Health Science Center at Houston, Houston, TX, 77030, United States of America
| | - Cihan M Kadipasaoglu
- Vivian L. Smith Department of Neurosurgery, McGovern Medical School at UT Health Houston, Houston, TX, 77030, United States of America
- Texas Institute for Restorative Neurotechnologies, University of Texas Health Science Center at Houston, Houston, TX, 77030, United States of America
| | - Christopher R Conner
- Vivian L. Smith Department of Neurosurgery, McGovern Medical School at UT Health Houston, Houston, TX, 77030, United States of America
- Memorial Hermann Hospital, Texas Medical Center, Houston, TX, 77030, United States of America
| | - Kiefer J Forseth
- Vivian L. Smith Department of Neurosurgery, McGovern Medical School at UT Health Houston, Houston, TX, 77030, United States of America
- Texas Institute for Restorative Neurotechnologies, University of Texas Health Science Center at Houston, Houston, TX, 77030, United States of America
| | - Patrick S Rollo
- Vivian L. Smith Department of Neurosurgery, McGovern Medical School at UT Health Houston, Houston, TX, 77030, United States of America
- Texas Institute for Restorative Neurotechnologies, University of Texas Health Science Center at Houston, Houston, TX, 77030, United States of America
| | - Matthew J Rollo
- Vivian L. Smith Department of Neurosurgery, McGovern Medical School at UT Health Houston, Houston, TX, 77030, United States of America
| | - Vatche G Baboyan
- Vivian L. Smith Department of Neurosurgery, McGovern Medical School at UT Health Houston, Houston, TX, 77030, United States of America
| | - Nitin Tandon
- Vivian L. Smith Department of Neurosurgery, McGovern Medical School at UT Health Houston, Houston, TX, 77030, United States of America.
- Texas Institute for Restorative Neurotechnologies, University of Texas Health Science Center at Houston, Houston, TX, 77030, United States of America.
- Memorial Hermann Hospital, Texas Medical Center, Houston, TX, 77030, United States of America.
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9
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Karthik G, Plass J, Beltz AM, Liu Z, Grabowecky M, Suzuki S, Stacey WC, Wasade VS, Towle VL, Tao JX, Wu S, Issa NP, Brang D. Visual speech differentially modulates beta, theta, and high gamma bands in auditory cortex. Eur J Neurosci 2021; 54:7301-7317. [PMID: 34587350 DOI: 10.1111/ejn.15482] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2021] [Revised: 08/20/2021] [Accepted: 08/28/2021] [Indexed: 12/13/2022]
Abstract
Speech perception is a central component of social communication. Although principally an auditory process, accurate speech perception in everyday settings is supported by meaningful information extracted from visual cues. Visual speech modulates activity in cortical areas subserving auditory speech perception including the superior temporal gyrus (STG). However, it is unknown whether visual modulation of auditory processing is a unitary phenomenon or, rather, consists of multiple functionally distinct processes. To explore this question, we examined neural responses to audiovisual speech measured from intracranially implanted electrodes in 21 patients with epilepsy. We found that visual speech modulated auditory processes in the STG in multiple ways, eliciting temporally and spatially distinct patterns of activity that differed across frequency bands. In the theta band, visual speech suppressed the auditory response from before auditory speech onset to after auditory speech onset (-93 to 500 ms) most strongly in the posterior STG. In the beta band, suppression was seen in the anterior STG from -311 to -195 ms before auditory speech onset and in the middle STG from -195 to 235 ms after speech onset. In high gamma, visual speech enhanced the auditory response from -45 to 24 ms only in the posterior STG. We interpret the visual-induced changes prior to speech onset as reflecting crossmodal prediction of speech signals. In contrast, modulations after sound onset may reflect a decrease in sustained feedforward auditory activity. These results are consistent with models that posit multiple distinct mechanisms supporting audiovisual speech perception.
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Affiliation(s)
- G Karthik
- Department of Psychology, University of Michigan, Ann Arbor, Michigan, USA
| | - John Plass
- Department of Psychology, University of Michigan, Ann Arbor, Michigan, USA
| | - Adriene M Beltz
- Department of Psychology, University of Michigan, Ann Arbor, Michigan, USA
| | - Zhongming Liu
- Department of Biomedical Engineering and Department of Electrical Engineering and Computer Science, University of Michigan, Ann Arbor, Michigan, USA
| | - Marcia Grabowecky
- Department of Psychology, Northwestern University, Evanston, Illinois, USA
| | - Satoru Suzuki
- Department of Psychology, Northwestern University, Evanston, Illinois, USA
| | - William C Stacey
- Department of Neurology and Department of Biomedical Engineering, University of Michigan, Ann Arbor, Michigan, USA
| | - Vibhangini S Wasade
- Department of Neurology, Henry Ford Hospital, Detroit, Michigan, USA.,Department of Neurology, Wayne State University School of Medicine, Detroit, Michigan, USA
| | - Vernon L Towle
- Department of Neurology, The University of Chicago, Chicago, Illinois, USA
| | - James X Tao
- Department of Neurology, The University of Chicago, Chicago, Illinois, USA
| | - Shasha Wu
- Department of Neurology, The University of Chicago, Chicago, Illinois, USA
| | - Naoum P Issa
- Department of Neurology, The University of Chicago, Chicago, Illinois, USA
| | - David Brang
- Department of Psychology, University of Michigan, Ann Arbor, Michigan, USA
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10
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NetDI: Methodology Elucidating the Role of Power and Dynamical Brain Network Features That Underpin Word Production. eNeuro 2021; 8:ENEURO.0177-20.2020. [PMID: 33293456 PMCID: PMC7890525 DOI: 10.1523/eneuro.0177-20.2020] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2020] [Revised: 11/13/2020] [Accepted: 11/19/2020] [Indexed: 12/03/2022] Open
Abstract
Canonical language models describe eloquent function as the product of a series of cognitive processes, typically characterized by the independent activation profiles of focal brain regions. In contrast, more recent work has suggested that the interactions between these regions, the cortical networks of language, are critical for understanding speech production. We investigated the cortical basis of picture naming (PN) with human intracranial electrocorticography (ECoG) recordings and direct cortical stimulation (DCS), adjudicating between two competing hypotheses: are task-specific cognitive functions discretely computed within well-localized brain regions or rather by distributed networks? The time resolution of ECoG allows direct comparison of intraregional activation measures [high gamma (hγ) power] with graph theoretic measures of interregional dynamics. We developed an analysis framework, network dynamics using directed information (NetDI), using information and graph theoretic tools to reveal spatiotemporal dynamics at multiple scales: coarse, intermediate, and fine. Our analysis found novel relationships between the power profiles and network measures during the task. Furthermore, validation using DCS indicates that such network parameters combined with hγ power are more predictive than hγ power alone, for identifying critical language regions in the brain. NetDI reveals a high-dimensional space of network dynamics supporting cortical language function, and to account for disruptions to language function observed after neurosurgical resection, traumatic injury, and degenerative disease.
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11
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Spatiotemporal dynamics of orthographic and lexical processing in the ventral visual pathway. Nat Hum Behav 2020; 5:389-398. [PMID: 33257877 PMCID: PMC10365894 DOI: 10.1038/s41562-020-00982-w] [Citation(s) in RCA: 42] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2020] [Accepted: 09/23/2020] [Indexed: 02/06/2023]
Abstract
Reading is a rapid, distributed process that engages multiple components of the ventral visual stream. To understand the neural constituents and their interactions that allow us to identify written words, we performed direct intra-cranial recordings in a large cohort of humans. This allowed us to isolate the spatiotemporal dynamics of visual word recognition across the entire left ventral occipitotemporal cortex. We found that mid-fusiform cortex is the first brain region sensitive to lexicality, preceding the traditional visual word form area. The magnitude and duration of its activation are driven by the statistics of natural language. Information regarding lexicality and word frequency propagates posteriorly from this region to visual word form regions and to earlier visual cortex, which, while active earlier, show sensitivity to words later. Further, direct electrical stimulation of this region results in reading arrest, further illustrating its crucial role in reading. This unique sensitivity of mid-fusiform cortex to sub-lexical and lexical characteristics points to its central role as the orthographic lexicon-the long-term memory representations of visual word forms.
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12
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Mégevand P, Mercier MR, Groppe DM, Zion Golumbic E, Mesgarani N, Beauchamp MS, Schroeder CE, Mehta AD. Crossmodal Phase Reset and Evoked Responses Provide Complementary Mechanisms for the Influence of Visual Speech in Auditory Cortex. J Neurosci 2020; 40:8530-8542. [PMID: 33023923 PMCID: PMC7605423 DOI: 10.1523/jneurosci.0555-20.2020] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2020] [Revised: 07/27/2020] [Accepted: 08/31/2020] [Indexed: 12/26/2022] Open
Abstract
Natural conversation is multisensory: when we can see the speaker's face, visual speech cues improve our comprehension. The neuronal mechanisms underlying this phenomenon remain unclear. The two main alternatives are visually mediated phase modulation of neuronal oscillations (excitability fluctuations) in auditory neurons and visual input-evoked responses in auditory neurons. Investigating this question using naturalistic audiovisual speech with intracranial recordings in humans of both sexes, we find evidence for both mechanisms. Remarkably, auditory cortical neurons track the temporal dynamics of purely visual speech using the phase of their slow oscillations and phase-related modulations in broadband high-frequency activity. Consistent with known perceptual enhancement effects, the visual phase reset amplifies the cortical representation of concomitant auditory speech. In contrast to this, and in line with earlier reports, visual input reduces the amplitude of evoked responses to concomitant auditory input. We interpret the combination of improved phase tracking and reduced response amplitude as evidence for more efficient and reliable stimulus processing in the presence of congruent auditory and visual speech inputs.SIGNIFICANCE STATEMENT Watching the speaker can facilitate our understanding of what is being said. The mechanisms responsible for this influence of visual cues on the processing of speech remain incompletely understood. We studied these mechanisms by recording the electrical activity of the human brain through electrodes implanted surgically inside the brain. We found that visual inputs can operate by directly activating auditory cortical areas, and also indirectly by modulating the strength of cortical responses to auditory input. Our results help to understand the mechanisms by which the brain merges auditory and visual speech into a unitary perception.
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Affiliation(s)
- Pierre Mégevand
- Department of Neurosurgery, Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, Hempstead, New York 11549
- Feinstein Institutes for Medical Research, Manhasset, New York 11030
- Department of Basic Neurosciences, Faculty of Medicine, University of Geneva, 1211 Geneva, Switzerland
| | - Manuel R Mercier
- Department of Neurology, Montefiore Medical Center, Bronx, New York 10467
- Department of Neuroscience, Albert Einstein College of Medicine, Bronx, New York 10461
- Institut de Neurosciences des Systèmes, Aix Marseille University, INSERM, 13005 Marseille, France
| | - David M Groppe
- Department of Neurosurgery, Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, Hempstead, New York 11549
- Feinstein Institutes for Medical Research, Manhasset, New York 11030
- The Krembil Neuroscience Centre, University Health Network, Toronto, Ontario M5T 1M8, Canada
| | - Elana Zion Golumbic
- The Gonda Brain Research Center, Bar Ilan University, Ramat Gan 5290002, Israel
| | - Nima Mesgarani
- Department of Electrical Engineering, Columbia University, New York, New York 10027
| | - Michael S Beauchamp
- Department of Neurosurgery, Baylor College of Medicine, Houston, Texas 77030
| | - Charles E Schroeder
- Nathan S. Kline Institute, Orangeburg, New York 10962
- Department of Psychiatry, Columbia University, New York, New York 10032
| | - Ashesh D Mehta
- Department of Neurosurgery, Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, Hempstead, New York 11549
- Feinstein Institutes for Medical Research, Manhasset, New York 11030
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13
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Woolnough O, Rollo PS, Forseth KJ, Kadipasaoglu CM, Ekstrom AD, Tandon N. Category Selectivity for Face and Scene Recognition in Human Medial Parietal Cortex. Curr Biol 2020; 30:2707-2715.e3. [PMID: 32502406 DOI: 10.1016/j.cub.2020.05.018] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2020] [Revised: 04/20/2020] [Accepted: 05/06/2020] [Indexed: 01/06/2023]
Abstract
The rapid recognition and memory of faces and scenes implies the engagement of category-specific computational hubs in the ventral visual stream with the distributed cortical memory network. To better understand how recognition and identification occur in humans, we performed direct intracranial recordings, in a large cohort of patients (n = 50), from the medial parietal cortex (MPC) and the medial temporal lobe (MTL), structures known to be engaged during face and scene identification. We discovered that the MPC is topologically tuned to face and scene recognition, with clusters in MPC performing scene recognition bilaterally and face recognition in right subparietal sulcus. The MTL displayed a selectivity gradient with anterior, entorhinal cortex showing face selectivity and posterior parahippocampal regions showing scene selectivity. In both MPC and MTL, stimulus-specific identifiable exemplars led to greater activity in these cortical patches. These two regions work in concert for recognition of faces and scenes. Feature selectivity and identity-sensitive activity in the two regions was coincident, and they exhibited theta-phase locking during face and scene recognition. These findings together provide clear evidence for a specific role of subregions in the MPC for the recognition of unique entities.
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Affiliation(s)
- Oscar Woolnough
- Vivian L. Smith Department of Neurosurgery, McGovern Medical School at UT Health Houston, Houston, TX 77030, USA; Texas Institute for Restorative Neurotechnologies, University of Texas Health Science Center at Houston, Houston, TX 77030, USA
| | - Patrick S Rollo
- Vivian L. Smith Department of Neurosurgery, McGovern Medical School at UT Health Houston, Houston, TX 77030, USA; Texas Institute for Restorative Neurotechnologies, University of Texas Health Science Center at Houston, Houston, TX 77030, USA
| | - Kiefer J Forseth
- Vivian L. Smith Department of Neurosurgery, McGovern Medical School at UT Health Houston, Houston, TX 77030, USA; Texas Institute for Restorative Neurotechnologies, University of Texas Health Science Center at Houston, Houston, TX 77030, USA
| | - Cihan M Kadipasaoglu
- Vivian L. Smith Department of Neurosurgery, McGovern Medical School at UT Health Houston, Houston, TX 77030, USA; Memorial Hermann Hospital, Texas Medical Center, Houston, TX 77030, USA
| | - Arne D Ekstrom
- Department of Psychology, University of Arizona, Tucson, AZ 85721, USA
| | - Nitin Tandon
- Vivian L. Smith Department of Neurosurgery, McGovern Medical School at UT Health Houston, Houston, TX 77030, USA; Texas Institute for Restorative Neurotechnologies, University of Texas Health Science Center at Houston, Houston, TX 77030, USA; Memorial Hermann Hospital, Texas Medical Center, Houston, TX 77030, USA.
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14
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Woolnough O, Forseth KJ, Rollo PS, Tandon N. Uncovering the functional anatomy of the human insula during speech. eLife 2019; 8:53086. [PMID: 31852580 PMCID: PMC6941893 DOI: 10.7554/elife.53086] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2019] [Accepted: 12/12/2019] [Indexed: 12/11/2022] Open
Abstract
The contribution of insular cortex to speech production remains unclear and controversial given diverse findings from functional neuroimaging and lesional data. To create a precise spatiotemporal map of insular activity, we performed a series of experiments: single-word articulations of varying complexity, non-speech orofacial movements and speech listening, in a cohort of 27 patients implanted with penetrating intracranial electrodes. The posterior insula was robustly active bilaterally, but after the onset of articulation, during listening to speech and during production of non-speech mouth movements. Preceding articulation there was very sparse activity, localized primarily to the frontal operculum rather than the insula. Posterior insular was active coincident with superior temporal gyrus but was more active for self-generated speech than external speech, the opposite of the superior temporal gyrus. These findings support the conclusion that the insula does not serve pre-articulatory preparatory roles.
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Affiliation(s)
- Oscar Woolnough
- Vivian L. Smith Department of Neurosurgery, McGovern Medical School at UT Health Houston, Houston, United States.,Texas Institute for Restorative Neurotechnologies, University of Texas Health Science Center at Houston, Houston, United States
| | - Kiefer James Forseth
- Vivian L. Smith Department of Neurosurgery, McGovern Medical School at UT Health Houston, Houston, United States.,Texas Institute for Restorative Neurotechnologies, University of Texas Health Science Center at Houston, Houston, United States
| | - Patrick Sarahan Rollo
- Vivian L. Smith Department of Neurosurgery, McGovern Medical School at UT Health Houston, Houston, United States.,Texas Institute for Restorative Neurotechnologies, University of Texas Health Science Center at Houston, Houston, United States
| | - Nitin Tandon
- Vivian L. Smith Department of Neurosurgery, McGovern Medical School at UT Health Houston, Houston, United States.,Texas Institute for Restorative Neurotechnologies, University of Texas Health Science Center at Houston, Houston, United States.,Memorial Hermann Hospital, Texas Medical Center, Houston, United States
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15
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Behncke J, Kern M, Ruescher J, Schulze-Bonhage A, Ball T. Probabilistic neuroanatomical assignment of intracranial electrodes using the ELAS toolbox. J Neurosci Methods 2019; 327:108396. [DOI: 10.1016/j.jneumeth.2019.108396] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2019] [Revised: 07/18/2019] [Accepted: 08/06/2019] [Indexed: 10/26/2022]
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16
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Forseth KJ, Kadipasaoglu CM, Conner CR, Hickok G, Knight RT, Tandon N. A lexical semantic hub for heteromodal naming in middle fusiform gyrus. Brain 2019; 141:2112-2126. [PMID: 29860298 DOI: 10.1093/brain/awy120] [Citation(s) in RCA: 89] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2018] [Accepted: 03/23/2018] [Indexed: 11/13/2022] Open
Abstract
Semantic memory underpins our understanding of objects, people, places, and ideas. Anomia, a disruption of semantic memory access, is the most common residual language disturbance and is seen in dementia and following injury to temporal cortex. While such anomia has been well characterized by lesion symptom mapping studies, its pathophysiology is not well understood. We hypothesize that inputs to the semantic memory system engage a specific heteromodal network hub that integrates lexical retrieval with the appropriate semantic content. Such a network hub has been proposed by others, but has thus far eluded precise spatiotemporal delineation. This limitation in our understanding of semantic memory has impeded progress in the treatment of anomia. We evaluated the cortical structure and dynamics of the lexical semantic network in driving speech production in a large cohort of patients with epilepsy using electrocorticography (n = 64), functional MRI (n = 36), and direct cortical stimulation (n = 30) during two generative language processes that rely on semantic knowledge: visual picture naming and auditory naming to definition. Each task also featured a non-semantic control condition: scrambled pictures and reversed speech, respectively. These large-scale data of the left, language-dominant hemisphere uniquely enable convergent, high-resolution analyses of neural mechanisms characterized by rapid, transient dynamics with strong interactions between distributed cortical substrates. We observed three stages of activity during both visual picture naming and auditory naming to definition that were serially organized: sensory processing, lexical semantic processing, and articulation. Critically, the second stage was absent in both the visual and auditory control conditions. Group activity maps from both electrocorticography and functional MRI identified heteromodal responses in middle fusiform gyrus, intraparietal sulcus, and inferior frontal gyrus; furthermore, the spectrotemporal profiles of these three regions revealed coincident activity preceding articulation. Only in the middle fusiform gyrus did direct cortical stimulation disrupt both naming tasks while still preserving the ability to repeat sentences. These convergent data strongly support a model in which a distinct neuroanatomical substrate in middle fusiform gyrus provides access to object semantic information. This under-appreciated locus of semantic processing is at risk in resections for temporal lobe epilepsy as well as in trauma and strokes that affect the inferior temporal cortex-it may explain the range of anomic states seen in these conditions. Further characterization of brain network behaviour engaging this region in both healthy and diseased states will expand our understanding of semantic memory and further development of therapies directed at anomia.
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Affiliation(s)
- Kiefer James Forseth
- Vivian L Smith Department of Neurosurgery, McGovern Medical School, Houston, TX, USA
| | | | | | - Gregory Hickok
- Department of Cognitive Sciences, University of California, Irvine, CA, USA
| | | | - Nitin Tandon
- Vivian L Smith Department of Neurosurgery, McGovern Medical School, Houston, TX, USA.,Memorial Hermann Hospital, Texas Medical Center, Houston, TX, USA
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17
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Rossion B, Jacques C, Jonas J. Mapping face categorization in the human ventral occipitotemporal cortex with direct neural intracranial recordings. Ann N Y Acad Sci 2018; 1426:5-24. [PMID: 29479704 DOI: 10.1111/nyas.13596] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2017] [Revised: 12/07/2017] [Accepted: 12/14/2017] [Indexed: 11/29/2022]
Abstract
The neural basis of face categorization has been widely investigated with functional magnetic resonance imaging (fMRI), identifying a set of face-selective local regions in the ventral occipitotemporal cortex (VOTC). However, indirect recording of neural activity with fMRI is associated with large fluctuations of signal across regions, often underestimating face-selective responses in the anterior VOTC. While direct recording of neural activity with subdural grids of electrodes (electrocorticography, ECoG) or depth electrodes (stereotactic electroencephalography, SEEG) offers a unique opportunity to fill this gap in knowledge, these studies rather reveal widely distributed face-selective responses. Moreover, intracranial recordings are complicated by interindividual variability in neuroanatomy, ambiguity in definition, and quantification of responses of interest, as well as limited access to sulci with ECoG. Here, we propose to combine SEEG in large samples of individuals with fast periodic visual stimulation to objectively define, quantify, and characterize face categorization across the whole VOTC. This approach reconciles the wide distribution of neural face categorization responses with their (right) hemispheric and regional specialization, and reveals several face-selective regions in anterior VOTC sulci. We outline the challenges of this research program to understand the neural basis of face categorization and high-level visual recognition in general.
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Affiliation(s)
- Bruno Rossion
- Psychological Sciences Research Institute, Institute of Neuroscience, University of Louvain (UCLouvain), Louvain-la-Neuve, Belgium
- Service de Neurologie, Centre Hospitalier Régional Universitaire (CHRU) de Nancy, Nancy, France
- CRAN, UMR 7039, CNRS et Université de Lorraine, Nancy, France
| | - Corentin Jacques
- Psychological Sciences Research Institute, Institute of Neuroscience, University of Louvain (UCLouvain), Louvain-la-Neuve, Belgium
- Research Group Psychiatry, Department of Neuroscience, University of Leuven, Leuven, Belgium
| | - Jacques Jonas
- Psychological Sciences Research Institute, Institute of Neuroscience, University of Louvain (UCLouvain), Louvain-la-Neuve, Belgium
- Service de Neurologie, Centre Hospitalier Régional Universitaire (CHRU) de Nancy, Nancy, France
- CRAN, UMR 7039, CNRS et Université de Lorraine, Nancy, France
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18
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Kadipasaoglu CM, Conner CR, Baboyan VG, Rollo M, Pieters TA, Tandon N. Network dynamics of human face perception. PLoS One 2017; 12:e0188834. [PMID: 29190811 PMCID: PMC5708727 DOI: 10.1371/journal.pone.0188834] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2017] [Accepted: 11/14/2017] [Indexed: 11/19/2022] Open
Abstract
Prevailing theories suggests that cortical regions responsible for face perception operate in a serial, feed-forward fashion. Here, we utilize invasive human electrophysiology to evaluate serial models of face-processing via measurements of cortical activation, functional connectivity, and cortico-cortical evoked potentials. We find that task-dependent changes in functional connectivity between face-selective regions in the inferior occipital (f-IOG) and fusiform gyrus (f-FG) are bidirectional, not feed-forward, and emerge following feed-forward input from early visual cortex (EVC) to both of these regions. Cortico-cortical evoked potentials similarly reveal independent signal propagations between EVC and both f-IOG and f-FG. These findings are incompatible with serial models, and support a parallel, distributed network underpinning face perception in humans.
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Affiliation(s)
- Cihan Mehmet Kadipasaoglu
- Vivian Smith Department of Neurosurgery, Univ. of Texas Medical School at Houston, Houston, Texas, United States of America
| | - Christopher Richard Conner
- Vivian Smith Department of Neurosurgery, Univ. of Texas Medical School at Houston, Houston, Texas, United States of America
| | - Vatche George Baboyan
- Vivian Smith Department of Neurosurgery, Univ. of Texas Medical School at Houston, Houston, Texas, United States of America
| | - Matthew Rollo
- Vivian Smith Department of Neurosurgery, Univ. of Texas Medical School at Houston, Houston, Texas, United States of America
| | - Thomas Allyn Pieters
- Vivian Smith Department of Neurosurgery, Univ. of Texas Medical School at Houston, Houston, Texas, United States of America
| | - Nitin Tandon
- Vivian Smith Department of Neurosurgery, Univ. of Texas Medical School at Houston, Houston, Texas, United States of America
- Memorial Hermann Hospital, Texas Medical Center, Houston, Texas, United States of America
- * E-mail:
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19
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Kadipasaoglu CM, Conner CR, Whaley ML, Baboyan VG, Tandon N. Category-Selectivity in Human Visual Cortex Follows Cortical Topology: A Grouped icEEG Study. PLoS One 2016; 11:e0157109. [PMID: 27272936 PMCID: PMC4896492 DOI: 10.1371/journal.pone.0157109] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2016] [Accepted: 05/24/2016] [Indexed: 01/20/2023] Open
Abstract
Neuroimaging studies suggest that category-selective regions in higher-order visual cortex are topologically organized around specific anatomical landmarks: the mid-fusiform sulcus (MFS) in the ventral temporal cortex (VTC) and lateral occipital sulcus (LOS) in the lateral occipital cortex (LOC). To derive precise structure-function maps from direct neural signals, we collected intracranial EEG (icEEG) recordings in a large human cohort (n = 26) undergoing implantation of subdural electrodes. A surface-based approach to grouped icEEG analysis was used to overcome challenges from sparse electrode coverage within subjects and variable cortical anatomy across subjects. The topology of category-selectivity in bilateral VTC and LOC was assessed for five classes of visual stimuli-faces, animate non-face (animals/body-parts), places, tools, and words-using correlational and linear mixed effects analyses. In the LOC, selectivity for living (faces and animate non-face) and non-living (places and tools) classes was arranged in a ventral-to-dorsal axis along the LOS. In the VTC, selectivity for living and non-living stimuli was arranged in a latero-medial axis along the MFS. Written word-selectivity was reliably localized to the intersection of the left MFS and the occipito-temporal sulcus. These findings provide direct electrophysiological evidence for topological information structuring of functional representations within higher-order visual cortex.
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Affiliation(s)
- Cihan Mehmet Kadipasaoglu
- Vivian Smith Department of Neurosurgery, University of Texas Medical School at Houston, Houston, TX, United States of America
| | - Christopher Richard Conner
- Vivian Smith Department of Neurosurgery, University of Texas Medical School at Houston, Houston, TX, United States of America
| | - Meagan Lee Whaley
- Vivian Smith Department of Neurosurgery, University of Texas Medical School at Houston, Houston, TX, United States of America
| | - Vatche George Baboyan
- Vivian Smith Department of Neurosurgery, University of Texas Medical School at Houston, Houston, TX, United States of America
| | - Nitin Tandon
- Vivian Smith Department of Neurosurgery, University of Texas Medical School at Houston, Houston, TX, United States of America
- Memorial Hermann Hospital, Texas Medical Center, Houston, TX, United States of America
- * E-mail:
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20
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Abstract
UNLABELLED Opinions are divided on whether word reading processes occur in a hierarchical, feedforward fashion or within an interactive framework. To critically evaluate these competing theories, we recorded electrocorticographic (ECoG) data from 15 human patients with intractable epilepsy during a word completion task and evaluated brain network dynamics across individuals. We used a novel technique of analyzing multihuman ECoG recordings to identify cortical regions most relevant to processing lexical information. The mid fusiform gyrus showed the strongest, earliest response after stimulus onset, whereas activity was maximal in frontal, dorsal lateral prefrontal, and sensorimotor regions toward articulation onset. To evaluate interregional functional connectivity, ECoG data from electrodes situated over specific cortical regions of interest were fit into linear multivariate autoregressive (MVAR) models. Spectral characteristics of the MVAR models were used to precisely reveal the timing and the magnitude of information flow between localized brain regions. This is the first application of MVAR for developing a comprehensive account of interregional interactions from a word reading ECoG dataset. Our comprehensive findings revealed both top-down and bottom-up influences between higher-level language areas and the mid fusiform gyrus. Our findings thus challenge strictly hierarchical, feedforward views of word reading and suggest that orthographic processes are modulated by prefrontal and sensorimotor regions via an interactive framework. SIGNIFICANCE STATEMENT Word reading is a critical part of everyday life. When the ability to read is disrupted, it can lead to learning disorders, as well as emotional and academic difficulties. The neural mechanisms underlying word reading are not well understood due to limitations in the spatial and temporal specificity of prior word reading studies. Our research analyzed data recorded from sensors implanted directly from surface of human brains while these individuals performed a word reading task. Our research analyzed these recordings to infer how brain regions communicate during word reading. Our original results improve upon current models of word reading and can be used to develop treatment plans for individuals with reading disabilities.
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21
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Abstract
A fine-grained description of the spatiotemporal dynamics of human brain activity is a major goal of neuroscientific research. Limitations in spatial and temporal resolution of available noninvasive recording and imaging techniques have hindered so far the acquisition of precise, comprehensive four-dimensional maps of human neural activity. The present study combines anatomical and functional data from intracerebral recordings of nearly 100 patients, to generate highly resolved four-dimensional maps of human cortical processing of nonpainful somatosensory stimuli. These maps indicate that the human somatosensory system devoted to the hand encompasses a widespread network covering more than 10% of the cortical surface of both hemispheres. This network includes phasic components, centered on primary somatosensory cortex and neighboring motor, premotor, and inferior parietal regions, and tonic components, centered on opercular and insular areas, and involving human parietal rostroventral area and ventral medial-superior-temporal area. The technique described opens new avenues for investigating the neural basis of all levels of cortical processing in humans.
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