1
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Saccone EJ, Tian M, Bedny M. Developing cortex is functionally pluripotent: Evidence from blindness. Dev Cogn Neurosci 2024; 66:101360. [PMID: 38394708 PMCID: PMC10899073 DOI: 10.1016/j.dcn.2024.101360] [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: 08/25/2023] [Revised: 01/25/2024] [Accepted: 02/19/2024] [Indexed: 02/25/2024] Open
Abstract
How rigidly does innate architecture constrain function of developing cortex? What is the contribution of early experience? We review insights into these questions from visual cortex function in people born blind. In blindness, occipital cortices are active during auditory and tactile tasks. What 'cross-modal' plasticity tells us about cortical flexibility is debated. On the one hand, visual networks of blind people respond to higher cognitive information, such as sentence grammar, suggesting drastic repurposing. On the other, in line with 'metamodal' accounts, sighted and blind populations show shared domain preferences in ventral occipito-temporal cortex (vOTC), suggesting visual areas switch input modality but perform the same or similar perceptual functions (e.g., face recognition) in blindness. Here we bring these disparate literatures together, reviewing and synthesizing evidence that speaks to whether visual cortices have similar or different functions in blind and sighted people. Together, the evidence suggests that in blindness, visual cortices are incorporated into higher-cognitive (e.g., fronto-parietal) networks, which are a major source long-range input to the visual system. We propose the connectivity-constrained experience-dependent account. Functional development is constrained by innate anatomical connectivity, experience and behavioral needs. Infant cortex is pluripotent, the same anatomical constraints develop into different functional outcomes.
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Affiliation(s)
- Elizabeth J Saccone
- Department of Psychological and Brain Sciences, Johns Hopkins University, Baltimore, MD, USA.
| | - Mengyu Tian
- Center for Educational Science and Technology, Beijing Normal University at Zhuhai, China
| | - Marina Bedny
- Department of Psychological and Brain Sciences, Johns Hopkins University, Baltimore, MD, USA
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2
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Beck J, Dzięgiel-Fivet G, Jednoróg K. Similarities and differences in the neural correlates of letter and speech sound integration in blind and sighted readers. Neuroimage 2023; 278:120296. [PMID: 37495199 DOI: 10.1016/j.neuroimage.2023.120296] [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: 03/08/2023] [Revised: 07/18/2023] [Accepted: 07/23/2023] [Indexed: 07/28/2023] Open
Abstract
Learning letter and speech sound (LS) associations is a major step in reading acquisition common for all alphabetic scripts, including Braille used by blind readers. The left superior temporal cortex (STC) plays an important role in audiovisual LS integration in sighted people, but it is still unknown what neural mechanisms are responsible for audiotactile LS integration in blind individuals. Here, we investigated the similarities and differences between LS integration in blind Braille (N = 42, age range: 9-60 y.o.) and sighted print (N = 47, age range: 9-60 y.o.) readers who acquired reading using different sensory modalities. In both groups, the STC responded to both isolated letters and isolated speech sounds, showed enhanced activation when they were presented together, and distinguished between congruent and incongruent letter and speech sound pairs. However, the direction of the congruency effect was different between the groups. Sighted subjects showed higher activity for incongruent LS pairs in the bilateral STC, similarly to previously studied typical readers of transparent orthographies. In the blind, congruent pairs resulted in an increased response in the right STC. These differences may be related to more sequential processing of Braille as compared to print reading. At the same time, behavioral efficiency in LS discrimination decisions and the congruency effect were found to be related to age and reading skill only in sighted participants, suggesting potential differences in the developmental trajectories of LS integration between blind and sighted readers.
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Affiliation(s)
- Joanna Beck
- Laboratory of Language Neurobiology, Nencki Institute of Experimental Biology, Polish Academy of Sciences, Pasteur 3, Warsaw 02-093, Poland.
| | - Gabriela Dzięgiel-Fivet
- Laboratory of Language Neurobiology, Nencki Institute of Experimental Biology, Polish Academy of Sciences, Pasteur 3, Warsaw 02-093, Poland
| | - Katarzyna Jednoróg
- Laboratory of Language Neurobiology, Nencki Institute of Experimental Biology, Polish Academy of Sciences, Pasteur 3, Warsaw 02-093, Poland.
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3
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Setti F, Handjaras G, Bottari D, Leo A, Diano M, Bruno V, Tinti C, Cecchetti L, Garbarini F, Pietrini P, Ricciardi E. A modality-independent proto-organization of human multisensory areas. Nat Hum Behav 2023; 7:397-410. [PMID: 36646839 PMCID: PMC10038796 DOI: 10.1038/s41562-022-01507-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2022] [Accepted: 12/05/2022] [Indexed: 01/18/2023]
Abstract
The processing of multisensory information is based upon the capacity of brain regions, such as the superior temporal cortex, to combine information across modalities. However, it is still unclear whether the representation of coherent auditory and visual events requires any prior audiovisual experience to develop and function. Here we measured brain synchronization during the presentation of an audiovisual, audio-only or video-only version of the same narrative in distinct groups of sensory-deprived (congenitally blind and deaf) and typically developed individuals. Intersubject correlation analysis revealed that the superior temporal cortex was synchronized across auditory and visual conditions, even in sensory-deprived individuals who lack any audiovisual experience. This synchronization was primarily mediated by low-level perceptual features, and relied on a similar modality-independent topographical organization of slow temporal dynamics. The human superior temporal cortex is naturally endowed with a functional scaffolding to yield a common representation across multisensory events.
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Affiliation(s)
- Francesca Setti
- MoMiLab, IMT School for Advanced Studies Lucca, Lucca, Italy
| | | | - Davide Bottari
- MoMiLab, IMT School for Advanced Studies Lucca, Lucca, Italy
| | - Andrea Leo
- Department of Translational Research and Advanced Technologies in Medicine and Surgery, University of Pisa, Pisa, Italy
| | - Matteo Diano
- Department of Psychology, University of Turin, Turin, Italy
| | - Valentina Bruno
- Manibus Lab, Department of Psychology, University of Turin, Turin, Italy
| | - Carla Tinti
- Department of Psychology, University of Turin, Turin, Italy
| | - Luca Cecchetti
- MoMiLab, IMT School for Advanced Studies Lucca, Lucca, Italy
| | | | - Pietro Pietrini
- MoMiLab, IMT School for Advanced Studies Lucca, Lucca, Italy
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4
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Bang JW, Chan RW, Parra C, Murphy MC, Schuman JS, Nau AC, Chan KC. Diverging patterns of plasticity in the nucleus basalis of Meynert in early- and late-onset blindness. Brain Commun 2023; 5:fcad119. [PMID: 37101831 PMCID: PMC10123399 DOI: 10.1093/braincomms/fcad119] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2022] [Revised: 02/01/2023] [Accepted: 04/07/2023] [Indexed: 04/28/2023] Open
Abstract
Plasticity in the brain is impacted by an individual's age at the onset of the blindness. However, what drives the varying degrees of plasticity remains largely unclear. One possible explanation attributes the mechanisms for the differing levels of plasticity to the cholinergic signals originating in the nucleus basalis of Meynert. This explanation is based on the fact that the nucleus basalis of Meynert can modulate cortical processes such as plasticity and sensory encoding through its widespread cholinergic projections. Nevertheless, there is no direct evidence indicating that the nucleus basalis of Meynert undergoes plastic changes following blindness. Therefore, using multiparametric magnetic resonance imaging, we examined if the structural and functional properties of the nucleus basalis of Meynert differ between early blind, late blind and sighted individuals. We observed that early and late blind individuals had a preserved volumetric size and cerebrovascular reactivity in the nucleus basalis of Meynert. However, we observed a reduction in the directionality of water diffusion in both early and late blind individuals compared to sighted individuals. Notably, the nucleus basalis of Meynert presented diverging patterns of functional connectivity between early and late blind individuals. This functional connectivity was enhanced at both global and local (visual, language and default-mode networks) levels in the early blind individuals, but there were little-to-no changes in the late blind individuals when compared to sighted controls. Furthermore, the age at onset of blindness predicted both global and local functional connectivity. These results suggest that upon reduced directionality of water diffusion in the nucleus basalis of Meynert, cholinergic influence may be stronger for the early blind compared to the late blind individuals. Our findings are important to unravelling why early blind individuals present stronger and more widespread cross-modal plasticity compared to late blind individuals.
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Affiliation(s)
- Ji Won Bang
- Correspondence may also be addressed to: Ji Won Bang, PhD.
| | - Russell W Chan
- Department of Ophthalmology, NYU Grossman School of Medicine, NYU Langone Health, New York University, New York, NY 10017, USA
| | - Carlos Parra
- Department of Ophthalmology, NYU Grossman School of Medicine, NYU Langone Health, New York University, New York, NY 10017, USA
| | - Matthew C Murphy
- Department of Radiology, Mayo Clinic, Rochester, MN 55905, USA
- Department of Ophthalmology, School of Medicine, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | - Joel S Schuman
- Department of Ophthalmology, NYU Grossman School of Medicine, NYU Langone Health, New York University, New York, NY 10017, USA
- Neuroscience Institute, NYU Grossman School of Medicine, NYU Langone Health, New York University, New York, NY 10016, USA
- Center for Neural Science, College of Arts and Science, New York University, New York, NY 10003, USA
- Department of Biomedical Engineering, Tandon School of Engineering, New York University, New York, NY 11201, USA
| | - Amy C Nau
- Department of Ophthalmology, School of Medicine, University of Pittsburgh, Pittsburgh, PA 15213, USA
- Korb and Associates, Boston, MA 02215, USA
| | - Kevin C Chan
- Correspondence to: Kevin C. Chan, PhD, Departments of Ophthalmology and Radiology, NYU Grossman School of Medicine, NYU Langone Health, New York University. 222 E 41st Street, Room 362, New York, NY 10017, USA.
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5
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Sabourin CJ, Merrikhi Y, Lomber SG. Do blind people hear better? Trends Cogn Sci 2022; 26:999-1012. [PMID: 36207258 DOI: 10.1016/j.tics.2022.08.016] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2022] [Revised: 08/22/2022] [Accepted: 08/25/2022] [Indexed: 01/12/2023]
Abstract
For centuries, anecdotal evidence such as the perfect pitch of the blind piano tuner or blind musician has supported the notion that individuals who have lost their sight early in life have superior hearing abilities compared with sighted people. Recently, auditory psychophysical and functional imaging studies have identified that specific auditory enhancements in the early blind can be linked to activation in extrastriate visual cortex, suggesting crossmodal plasticity. Furthermore, the nature of the sensory reorganization in occipital cortex supports the concept of a task-based functional cartography for the cerebral cortex rather than a sensory-based organization. In total, studies of early-blind individuals provide valuable insights into mechanisms of cortical plasticity and principles of cerebral organization.
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Affiliation(s)
- Carina J Sabourin
- Department of Physiology, McGill University, Montreal, Quebec H3G 1Y6, Canada; Biological and Biomedical Engineering Graduate Program, McGill University, Montreal, Quebec H3G 1Y6, Canada
| | - Yaser Merrikhi
- Department of Physiology, McGill University, Montreal, Quebec H3G 1Y6, Canada
| | - Stephen G Lomber
- Department of Physiology, McGill University, Montreal, Quebec H3G 1Y6, Canada; Biological and Biomedical Engineering Graduate Program, McGill University, Montreal, Quebec H3G 1Y6, Canada; Department of Psychology, McGill University, Montreal, Quebec H3G 1Y6, Canada; Department of Neurology and Neurosurgery, McGill University, Montreal, Quebec H3G 1Y6, Canada.
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6
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Arbel R, Heimler B, Amedi A. Face shape processing via visual-to-auditory sensory substitution activates regions within the face processing networks in the absence of visual experience. Front Neurosci 2022; 16:921321. [PMID: 36263367 PMCID: PMC9576157 DOI: 10.3389/fnins.2022.921321] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2022] [Accepted: 09/05/2022] [Indexed: 11/16/2022] Open
Abstract
Previous evidence suggests that visual experience is crucial for the emergence and tuning of the typical neural system for face recognition. To challenge this conclusion, we trained congenitally blind adults to recognize faces via visual-to-auditory sensory-substitution (SDD). Our results showed a preference for trained faces over other SSD-conveyed visual categories in the fusiform gyrus and in other known face-responsive-regions of the deprived ventral visual stream. We also observed a parametric modulation in the same cortical regions, for face orientation (upright vs. inverted) and face novelty (trained vs. untrained). Our results strengthen the conclusion that there is a predisposition for sensory-independent and computation-specific processing in specific cortical regions that can be retained in life-long sensory deprivation, independently of previous perceptual experience. They also highlight that if the right training is provided, such cortical preference maintains its tuning to what were considered visual-specific face features.
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Affiliation(s)
- Roni Arbel
- Department of Medical Neurobiology, Hadassah Ein-Kerem, Hebrew University of Jerusalem, Jerusalem, Israel
- Faculty of Medicine, Hebrew University of Jerusalem, Jerusalem, Israel
- Department of Pediatrics, Hadassah University Hospital-Mount Scopus, Jerusalem, Israel
- *Correspondence: Roni Arbel,
| | - Benedetta Heimler
- Department of Medical Neurobiology, Hadassah Ein-Kerem, Hebrew University of Jerusalem, Jerusalem, Israel
- Ivcher School of Psychology, The Institute for Brain, Mind, and Technology, Reichman University, Herzeliya, Israel
- Center of Advanced Technologies in Rehabilitation, Sheba Medical Center, Ramat Gan, Israel
| | - Amir Amedi
- Department of Medical Neurobiology, Hadassah Ein-Kerem, Hebrew University of Jerusalem, Jerusalem, Israel
- Ivcher School of Psychology, The Institute for Brain, Mind, and Technology, Reichman University, Herzeliya, Israel
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7
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Musz E, Loiotile R, Chen J, Cusack R, Bedny M. Naturalistic stimuli reveal a sensitive period in cross modal responses of visual cortex: Evidence from adult-onset blindness. Neuropsychologia 2022; 172:108277. [PMID: 35636634 PMCID: PMC9648859 DOI: 10.1016/j.neuropsychologia.2022.108277] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2021] [Revised: 04/28/2022] [Accepted: 05/25/2022] [Indexed: 01/31/2023]
Abstract
How do life experiences impact cortical function? In people who are born blind, the "visual" cortices are recruited during nonvisual tasks, such as Braille reading and sound localization. Do visual cortices have a latent capacity to respond to nonvisual information throughout the lifespan? Alternatively, is there a sensitive period of heightened plasticity that makes visual cortex repurposing especially possible during childhood? To gain insight into these questions, we leveraged meaningful naturalistic auditory stimuli to simultaneously engage a broad range of cognitive domains and quantify cross-modal responses across congenitally blind (n = 22), adult-onset blind (vision loss >18 years-of-age, n = 14) and sighted (n = 22) individuals. During fMRI scanning, participants listened to two types of meaningful naturalistic auditory stimuli: excerpts from movies and a spoken narrative. As controls, participants heard the same narrative with the sentences shuffled and the narrative played backwards (i.e., meaningless sounds). We correlated the voxel-wise timecourses of different participants within condition and group. For all groups, all stimulus conditions induced synchrony in auditory cortex while only the narrative stimuli synchronized responses in higher-cognitive fronto-parietal and temporal regions. As previously reported, inter-subject synchrony in visual cortices was higher in congenitally blind than sighted blindfolded participants and this between-group difference was particularly pronounced for meaningful stimuli (movies and narrative). Critically, visual cortex synchrony was no higher in adult-onset blind than sighted blindfolded participants and did not increase with blindness duration. Sensitive period plasticity enables cross-modal repurposing in visual cortices.
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Affiliation(s)
- Elizabeth Musz
- Department of Psychological and Brain Sciences, Johns Hopkins University, Baltimore, MD, USA
| | - Rita Loiotile
- Department of Psychological and Brain Sciences, Johns Hopkins University, Baltimore, MD, USA
| | - Janice Chen
- Department of Psychological and Brain Sciences, Johns Hopkins University, Baltimore, MD, USA
| | - Rhodri Cusack
- Trinity College Institute of Neuroscience, School of Psychology, Trinity College Dublin, Dublin, Ireland
| | - Marina Bedny
- Department of Psychological and Brain Sciences, Johns Hopkins University, Baltimore, MD, USA
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8
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Arcos K, Jaeggi SM, Grossman ED. Perks of Blindness: Enhanced Verbal Memory Span in Blind over Sighted Adults. Brain Res 2022; 1789:147943. [DOI: 10.1016/j.brainres.2022.147943] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2021] [Revised: 04/10/2022] [Accepted: 05/08/2022] [Indexed: 11/02/2022]
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9
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Kanjlia S, Loiotile RE, Harhen N, Bedny M. 'Visual' cortices of congenitally blind adults are sensitive to response selection demands in a go/no-go task. Neuroimage 2021; 236:118023. [PMID: 33862241 PMCID: PMC8249356 DOI: 10.1016/j.neuroimage.2021.118023] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2020] [Revised: 02/16/2021] [Accepted: 03/27/2021] [Indexed: 01/24/2023] Open
Abstract
Studies of occipital cortex plasticity in blindness provide insight into how intrinsic constraints interact with experience to determine cortical specialization. We tested the cognitive nature and anatomical origins of occipital responses during non-verbal, non-spatial auditory tasks. In a go/no-go task, congenitally blind (N=23) and sighted (N=24) individuals heard rapidly occurring (<1/s) non-verbal sounds and made one of two button presses (frequent-go 50%, infrequent-go 25%) or withheld a response (no-go, 25%). Rapid and frequent button presses heighten response selection/inhibition demands on the no-go trials: In sighted and blind adults a right-lateralized prefrontal (PFC) network responded most to no-go trials, followed by infrequent-go and finally frequent-go trials. In the blind group only, a right-lateralized occipital network showed the same response profile and the laterality of occipital and PFC responses was correlated across blind individuals. A second experiment with spoken sentences and equations (N=16) found that no-go responses in occipital cortex are distinct from previously identified occipital responses to spoken language. Finally, in resting-state data (N=30 blind, N=31 blindfolded sighted), no-go responsive 'visual' cortex of blind relative to sighted participants was more synchronized with PFC and less synchronized with primary auditory and sensory-motor cortices. No-go responsive occipital cortex showed higher resting-state correlations with no-go responsive PFC than language responsive inferior frontal cortex. We conclude that in blindness, a right-lateralized occipital network responds to non-verbal executive processes, including response selection. These results suggest that connectivity with fronto-parietal executive networks is a key mechanism for plasticity in blindness.
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Affiliation(s)
- Shipra Kanjlia
- Department of Psychological and Brain Sciences, Johns Hopkins University, United States; Department of Psychology, Carnegie Mellon University, 346 Baker Hall, 5000 Forbes Avenue, Pittsburgh, PA 15213, United States.
| | - Rita E Loiotile
- Department of Psychological and Brain Sciences, Johns Hopkins University, United States; Facebook, United States
| | - Nora Harhen
- Department of Psychological and Brain Sciences, Johns Hopkins University, United States; Department of Cognitive Sciences, University of California Irvine, United States
| | - Marina Bedny
- Department of Psychological and Brain Sciences, Johns Hopkins University, United States
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10
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Raz G, Saxe R. Learning in Infancy Is Active, Endogenously Motivated, and Depends on the Prefrontal Cortices. ACTA ACUST UNITED AC 2020. [DOI: 10.1146/annurev-devpsych-121318-084841] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
A common view of learning in infancy emphasizes the role of incidental sensory experiences from which increasingly abstract statistical regularities are extracted. In this view, infant brains initially support basic sensory and motor functions, followed by maturation of higher-level association cortex. Here, we critique this view and posit that, by contrast and more like adults, infants are active, endogenously motivated learners who structure their own learning through flexible selection of attentional targets and active interventions on their environment. We further argue that the infant brain, and particularly the prefrontal cortex (PFC), is well equipped to support these learning behaviors. We review recent progress in characterizing the function of the infant PFC, which suggests that, as in adults, the PFC is functionally specialized and highly connected. Together, we present an integrative account of infant minds and brains, in which the infant PFC represents multiple intrinsic motivations, which are leveraged for active learning.
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Affiliation(s)
- Gal Raz
- Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - Rebecca Saxe
- Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
- McGovern Institute for Brain Research, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
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11
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Cheng Q, Silvano E, Bedny M. Sensitive periods in cortical specialization for language: insights from studies with Deaf and blind individuals. Curr Opin Behav Sci 2020; 36:169-176. [PMID: 33718533 PMCID: PMC7945734 DOI: 10.1016/j.cobeha.2020.10.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
Studies with Deaf and blind individuals demonstrate that linguistic and sensory experiences during sensitive periods have potent effects on neurocognitive basis of language. Native users of sign and spoken languages recruit similar fronto-temporal systems during language processing. By contrast, delays in sign language access impact proficiency and the neural basis of language. Analogously, early but not late-onset blindness modifies the neural basis of language. People born blind recruit 'visual' areas during language processing, show reduced left-lateralization of language and enhanced performance on some language tasks. Sensitive period plasticity in and outside fronto-temporal language systems shapes the neural basis of language.
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Affiliation(s)
- Qi Cheng
- University of California San Diego
- University of Washington
| | - Emily Silvano
- Federal University of Rio de Janeiro
- Johns Hopkins University
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12
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Fedorenko E, Blank IA, Siegelman M, Mineroff Z. Lack of selectivity for syntax relative to word meanings throughout the language network. Cognition 2020; 203:104348. [PMID: 32569894 DOI: 10.1101/477851] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2018] [Revised: 05/14/2020] [Accepted: 05/31/2020] [Indexed: 05/25/2023]
Abstract
To understand what you are reading now, your mind retrieves the meanings of words and constructions from a linguistic knowledge store (lexico-semantic processing) and identifies the relationships among them to construct a complex meaning (syntactic or combinatorial processing). Do these two sets of processes rely on distinct, specialized mechanisms or, rather, share a common pool of resources? Linguistic theorizing, empirical evidence from language acquisition and processing, and computational modeling have jointly painted a picture whereby lexico-semantic and syntactic processing are deeply inter-connected and perhaps not separable. In contrast, many current proposals of the neural architecture of language continue to endorse a view whereby certain brain regions selectively support syntactic/combinatorial processing, although the locus of such "syntactic hub", and its nature, vary across proposals. Here, we searched for selectivity for syntactic over lexico-semantic processing using a powerful individual-subjects fMRI approach across three sentence comprehension paradigms that have been used in prior work to argue for such selectivity: responses to lexico-semantic vs. morpho-syntactic violations (Experiment 1); recovery from neural suppression across pairs of sentences differing in only lexical items vs. only syntactic structure (Experiment 2); and same/different meaning judgments on such sentence pairs (Experiment 3). Across experiments, both lexico-semantic and syntactic conditions elicited robust responses throughout the left fronto-temporal language network. Critically, however, no regions were more strongly engaged by syntactic than lexico-semantic processing, although some regions showed the opposite pattern. Thus, contra many current proposals of the neural architecture of language, syntactic/combinatorial processing is not separable from lexico-semantic processing at the level of brain regions-or even voxel subsets-within the language network, in line with strong integration between these two processes that has been consistently observed in behavioral and computational language research. The results further suggest that the language network may be generally more strongly concerned with meaning than syntactic form, in line with the primary function of language-to share meanings across minds.
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Affiliation(s)
- Evelina Fedorenko
- Department of Brain and Cognitive Sciences, MIT, Cambridge, MA 02139, USA; McGovern Institute for Brain Research, MIT, Cambridge, MA 02139, USA.
| | - Idan Asher Blank
- Department of Brain and Cognitive Sciences, MIT, Cambridge, MA 02139, USA; Department of Psychology, UCLA, Los Angeles, CA 90095, USA
| | - Matthew Siegelman
- Department of Brain and Cognitive Sciences, MIT, Cambridge, MA 02139, USA; Department of Psychology, Columbia University, New York, NY 10027, USA
| | - Zachary Mineroff
- Department of Brain and Cognitive Sciences, MIT, Cambridge, MA 02139, USA; Eberly Center for Teaching Excellence & Educational Innovation, CMU, Pittsburgh, PA 15213, USA
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13
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Fedorenko E, Blank IA, Siegelman M, Mineroff Z. Lack of selectivity for syntax relative to word meanings throughout the language network. Cognition 2020; 203:104348. [PMID: 32569894 PMCID: PMC7483589 DOI: 10.1016/j.cognition.2020.104348] [Citation(s) in RCA: 61] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2018] [Revised: 05/14/2020] [Accepted: 05/31/2020] [Indexed: 12/31/2022]
Abstract
To understand what you are reading now, your mind retrieves the meanings of words and constructions from a linguistic knowledge store (lexico-semantic processing) and identifies the relationships among them to construct a complex meaning (syntactic or combinatorial processing). Do these two sets of processes rely on distinct, specialized mechanisms or, rather, share a common pool of resources? Linguistic theorizing, empirical evidence from language acquisition and processing, and computational modeling have jointly painted a picture whereby lexico-semantic and syntactic processing are deeply inter-connected and perhaps not separable. In contrast, many current proposals of the neural architecture of language continue to endorse a view whereby certain brain regions selectively support syntactic/combinatorial processing, although the locus of such "syntactic hub", and its nature, vary across proposals. Here, we searched for selectivity for syntactic over lexico-semantic processing using a powerful individual-subjects fMRI approach across three sentence comprehension paradigms that have been used in prior work to argue for such selectivity: responses to lexico-semantic vs. morpho-syntactic violations (Experiment 1); recovery from neural suppression across pairs of sentences differing in only lexical items vs. only syntactic structure (Experiment 2); and same/different meaning judgments on such sentence pairs (Experiment 3). Across experiments, both lexico-semantic and syntactic conditions elicited robust responses throughout the left fronto-temporal language network. Critically, however, no regions were more strongly engaged by syntactic than lexico-semantic processing, although some regions showed the opposite pattern. Thus, contra many current proposals of the neural architecture of language, syntactic/combinatorial processing is not separable from lexico-semantic processing at the level of brain regions-or even voxel subsets-within the language network, in line with strong integration between these two processes that has been consistently observed in behavioral and computational language research. The results further suggest that the language network may be generally more strongly concerned with meaning than syntactic form, in line with the primary function of language-to share meanings across minds.
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Affiliation(s)
- Evelina Fedorenko
- Department of Brain and Cognitive Sciences, MIT, Cambridge, MA 02139, USA; McGovern Institute for Brain Research, MIT, Cambridge, MA 02139, USA.
| | - Idan Asher Blank
- Department of Brain and Cognitive Sciences, MIT, Cambridge, MA 02139, USA; Department of Psychology, UCLA, Los Angeles, CA 90095, USA
| | - Matthew Siegelman
- Department of Brain and Cognitive Sciences, MIT, Cambridge, MA 02139, USA; Department of Psychology, Columbia University, New York, NY 10027, USA
| | - Zachary Mineroff
- Department of Brain and Cognitive Sciences, MIT, Cambridge, MA 02139, USA; Eberly Center for Teaching Excellence & Educational Innovation, CMU, Pittsburgh, PA 15213, USA
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14
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Fandakova Y, Hartley CA. Mechanisms of learning and plasticity in childhood and adolescence. Dev Cogn Neurosci 2020; 42:100764. [PMID: 32072937 PMCID: PMC7013153 DOI: 10.1016/j.dcn.2020.100764] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Affiliation(s)
- Yana Fandakova
- Center for Lifespan Psychology, Max Planck Institute for Human Development, Berlin, Germany.
| | - Catherine A Hartley
- Department of Psychology and Center for Neural Science, New York University.
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