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Raffin E, Salamanca-Giron RF, Huxlin KR, Reynaud O, Mattera L, Martuzzi R, Hummel FC. TU-122. Adaptive brain changes to TMS Over V1 and V5 determined by concurrent TMS-fMRI. Clin Neurophysiol 2022. [DOI: 10.1016/j.clinph.2022.07.026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Akselrod M, Martuzzi R, van der Zwaag W, Blanke O, Serino A. Relation between palm and finger cortical representations in primary somatosensory cortex: A 7T fMRI study. Hum Brain Mapp 2021; 42:2262-2277. [PMID: 33621380 PMCID: PMC8046155 DOI: 10.1002/hbm.25365] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2020] [Revised: 01/20/2021] [Accepted: 01/28/2021] [Indexed: 01/08/2023] Open
Abstract
Many studies focused on the cortical representations of fingers, while the palm is relatively neglected despite its importance for hand function. Here, we investigated palm representation (PR) and its relationship with finger representations (FRs) in primary somatosensory cortex (S1). Few studies in humans suggested that PR is located medially with respect to FRs in S1, yet to date, no study directly quantified the somatotopic organization of PR and the five FRs. Importantly, the link between the somatotopic organization of PR and FRs and their activation properties remains largely unexplored. Using 7T fMRI, we mapped PR and the five FRs at the single subject level. First, we analyzed the cortical distance between PR and FRs to determine their somatotopic organization. Results show that PR was located medially with respect to D5. Second, we tested whether the observed cortical distances would predict the relationship between PR and FRs activations. Using three complementary measures (cross-activations, pattern similarity and resting-state connectivity), we show that the relationship between PR and FRs activations were not determined by their somatotopic organization, that is, there was no gradient moving from D5 to D1, except for resting-state connectivity, which was predicted by the somatotopy. Instead, we show that the representational geometry of PR and FRs activations reflected the physical structure of the hand. Collectively, our findings suggest that the spatial proximity between topographically organized neuronal populations do not necessarily predicts their functional properties, rather the structure of the sensory space (e.g., the hand shape) better describes the observed results.
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Affiliation(s)
- Michel Akselrod
- Laboratory MySpace, Department of Clinical Neuroscience, University Hospital of Lausanne (CHUV), Lausanne, Switzerland.,Laboratory of Cognitive Neuroscience, Brain Mind Institute and Center for Neuroprosthetics, Swiss Federal Institute of Technology of Lausanne (EPFL), Geneva, Switzerland.,Minded Program, CMON Unit, Italian Institute of Technology, Genoa, Italy
| | - Roberto Martuzzi
- Laboratory of Cognitive Neuroscience, Brain Mind Institute and Center for Neuroprosthetics, Swiss Federal Institute of Technology of Lausanne (EPFL), Geneva, Switzerland.,Foundation Campus Biotech Geneva, Geneva, Switzerland
| | | | - Olaf Blanke
- Laboratory of Cognitive Neuroscience, Brain Mind Institute and Center for Neuroprosthetics, Swiss Federal Institute of Technology of Lausanne (EPFL), Geneva, Switzerland.,Department of Neurology, University Hospital, Geneva, Switzerland
| | - Andrea Serino
- Laboratory MySpace, Department of Clinical Neuroscience, University Hospital of Lausanne (CHUV), Lausanne, Switzerland.,Laboratory of Cognitive Neuroscience, Brain Mind Institute and Center for Neuroprosthetics, Swiss Federal Institute of Technology of Lausanne (EPFL), Geneva, Switzerland
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Liverani MC, Freitas LGA, Siffredi V, Mikneviciute G, Martuzzi R, Meskaldij D, Borradori Tolsa C, Ha‐Vinh Leuchter R, Schnider A, Van De Ville D, Hüppi PS. Get real: Orbitofrontal cortex mediates the ability to sense reality in early adolescents. Brain Behav 2020; 10:e01552. [PMID: 32073744 PMCID: PMC7177588 DOI: 10.1002/brb3.1552] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/05/2019] [Revised: 01/06/2020] [Accepted: 01/08/2020] [Indexed: 12/11/2022] Open
Abstract
INTRODUCTION Orbitofrontal reality filtering (ORFi) is a memory mechanism that distinguishes whether a thought is relevant to present reality or not. In adults, it is mediated by the orbitofrontal cortex (OFC). This region is still not fully developed in preteenagers, but ORFi is already active from age 7. Here, we probe the neural correlates of ORFi in early adolescents, hypothesizing that OFC mediates the sense of reality in this population. METHODS Functional magnetic resonance images (fMRI) were acquired in 22 early adolescents during a task composed of two runs: run 1 measuring recognition capacity; run 2 measuring ORFi; each containing two types of images (conditions): distractors (D: images seen for the first time in the current run) and targets (T: images seen for the second time in the current run). Group region of interest (ROI) analysis was performed in a flexible factorial design with two factors (run and condition) using SPM12. RESULTS We found significant main effects for the experimental run and condition. The bilateral OFC activation was higher during ORFi than during the first run. Additionally, the OFC was more active while processing distractors than targets. CONCLUSION These results confirm, for the first time, the role of OFC in reality filtering in early adolescents.
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Affiliation(s)
- Maria Chiara Liverani
- Department of Paediatrics, Gynecology and ObstetricsDivision of Development and GrowthGeneva University HospitalsGenevaSwitzerland
| | - Lorena G. A. Freitas
- Department of Paediatrics, Gynecology and ObstetricsDivision of Development and GrowthGeneva University HospitalsGenevaSwitzerland
- Institute of BioengineeringÉcole Polytechnique Fédérale de LausanneLausanneSwitzerland
| | - Vanessa Siffredi
- Department of Paediatrics, Gynecology and ObstetricsDivision of Development and GrowthGeneva University HospitalsGenevaSwitzerland
- Institute of BioengineeringÉcole Polytechnique Fédérale de LausanneLausanneSwitzerland
| | - Greta Mikneviciute
- Department of Paediatrics, Gynecology and ObstetricsDivision of Development and GrowthGeneva University HospitalsGenevaSwitzerland
| | | | - Djalel‐Eddine Meskaldij
- Department of Paediatrics, Gynecology and ObstetricsDivision of Development and GrowthGeneva University HospitalsGenevaSwitzerland
- Institute of MathematicsÉcole Polytechnique Fédérale de LausanneLausanneSwitzerland
| | - Cristina Borradori Tolsa
- Department of Paediatrics, Gynecology and ObstetricsDivision of Development and GrowthGeneva University HospitalsGenevaSwitzerland
| | - Russia Ha‐Vinh Leuchter
- Department of Paediatrics, Gynecology and ObstetricsDivision of Development and GrowthGeneva University HospitalsGenevaSwitzerland
| | - Armin Schnider
- Department of Clinical NeurosciencesDivision of NeurorehabilitationGeneva University HospitalsGenevaSwitzerland
| | - Dimitri Van De Ville
- Institute of BioengineeringÉcole Polytechnique Fédérale de LausanneLausanneSwitzerland
| | - Petra Susan Hüppi
- Department of Paediatrics, Gynecology and ObstetricsDivision of Development and GrowthGeneva University HospitalsGenevaSwitzerland
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Kinany N, Pirondini E, Martuzzi R, Mattera L, Micera S, Van de Ville D. Functional imaging of rostrocaudal spinal activity during upper limb motor tasks. Neuroimage 2019; 200:590-600. [DOI: 10.1016/j.neuroimage.2019.05.036] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2019] [Revised: 05/12/2019] [Accepted: 05/13/2019] [Indexed: 11/25/2022] Open
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Serino A, Akselrod M, Salomon R, Martuzzi R, Blefari ML, Canzoneri E, Rognini G, van der Zwaag W, Iakova M, Luthi F, Amoresano A, Kuiken T, Blanke O. Upper limb cortical maps in amputees with targeted muscle and sensory reinnervation. Brain 2017; 140:2993-3011. [PMID: 29088353 DOI: 10.1093/brain/awx242] [Citation(s) in RCA: 58] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2016] [Accepted: 08/03/2017] [Indexed: 12/23/2022] Open
Abstract
Neuroprosthetics research in amputee patients aims at developing new prostheses that move and feel like real limbs. Targeted muscle and sensory reinnervation (TMSR) is such an approach and consists of rerouting motor and sensory nerves from the residual limb towards intact muscles and skin regions. Movement of the myoelectric prosthesis is enabled via decoded electromyography activity from reinnervated muscles and touch sensation on the missing limb is enabled by stimulation of the reinnervated skin areas. Here we ask whether and how motor control and redirected somatosensory stimulation provided via TMSR affected the maps of the upper limb in primary motor (M1) and primary somatosensory (S1) cortex, as well as their functional connections. To this aim, we tested three TMSR patients and investigated the extent, strength, and topographical organization of the missing limb and several control body regions in M1 and S1 at ultra high-field (7 T) functional magnetic resonance imaging. Additionally, we analysed the functional connectivity between M1 and S1 and of both these regions with fronto-parietal regions, known to be important for multisensory upper limb processing. These data were compared with those of control amputee patients (n = 6) and healthy controls (n = 12). We found that M1 maps of the amputated limb in TMSR patients were similar in terms of extent, strength, and topography to healthy controls and different from non-TMSR patients. S1 maps of TMSR patients were also more similar to normal conditions in terms of topographical organization and extent, as compared to non-targeted muscle and sensory reinnervation patients, but weaker in activation strength compared to healthy controls. Functional connectivity in TMSR patients between upper limb maps in M1 and S1 was comparable with healthy controls, while being reduced in non-TMSR patients. However, connectivity was reduced between S1 and fronto-parietal regions, in both the TMSR and non-TMSR patients with respect to healthy controls. This was associated with the absence of a well-established multisensory effect (visual enhancement of touch) in TMSR patients. Collectively, these results show how M1 and S1 process signals related to movement and touch are enabled by targeted muscle and sensory reinnervation. Moreover, they suggest that TMSR may counteract maladaptive cortical plasticity typically found after limb loss, in M1, partially in S1, and in their mutual connectivity. The lack of multisensory interaction in the present data suggests that further engineering advances are necessary (e.g. the integration of somatosensory feedback into current prostheses) to enable prostheses that move and feel as real limbs.
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Affiliation(s)
- Andrea Serino
- Center for Neuroprosthetics, Swiss Federal Institute of Technology of Lausanne (EPFL), chemin des mines 9, 1202 Geneva, Switzerland.,Laboratory of Cognitive Neuroscience, Faculty of Life Science, Swiss Federal Institute of Technology of Lausanne (EPFL), chemin des mines 9, 1202 Geneva, Switzerland.,Department of Clinical Neurosciences, University Hospital Lausanne (CHUV), Switzerland
| | - Michel Akselrod
- Center for Neuroprosthetics, Swiss Federal Institute of Technology of Lausanne (EPFL), chemin des mines 9, 1202 Geneva, Switzerland.,Laboratory of Cognitive Neuroscience, Faculty of Life Science, Swiss Federal Institute of Technology of Lausanne (EPFL), chemin des mines 9, 1202 Geneva, Switzerland.,Department of Clinical Neurosciences, University Hospital Lausanne (CHUV), Switzerland
| | - Roy Salomon
- Center for Neuroprosthetics, Swiss Federal Institute of Technology of Lausanne (EPFL), chemin des mines 9, 1202 Geneva, Switzerland.,Laboratory of Cognitive Neuroscience, Faculty of Life Science, Swiss Federal Institute of Technology of Lausanne (EPFL), chemin des mines 9, 1202 Geneva, Switzerland.,The Gonda Multidisciplinary Brain Research Center, Bar-Ilan University, Ramat Gan, Israel
| | - Roberto Martuzzi
- Center for Neuroprosthetics, Swiss Federal Institute of Technology of Lausanne (EPFL), chemin des mines 9, 1202 Geneva, Switzerland.,Laboratory of Cognitive Neuroscience, Faculty of Life Science, Swiss Federal Institute of Technology of Lausanne (EPFL), chemin des mines 9, 1202 Geneva, Switzerland.,Campus Biotech Geneva, Geneva, Switzerland
| | - Maria Laura Blefari
- Center for Neuroprosthetics, Swiss Federal Institute of Technology of Lausanne (EPFL), chemin des mines 9, 1202 Geneva, Switzerland.,Laboratory of Cognitive Neuroscience, Faculty of Life Science, Swiss Federal Institute of Technology of Lausanne (EPFL), chemin des mines 9, 1202 Geneva, Switzerland
| | - Elisa Canzoneri
- Center for Neuroprosthetics, Swiss Federal Institute of Technology of Lausanne (EPFL), chemin des mines 9, 1202 Geneva, Switzerland.,Laboratory of Cognitive Neuroscience, Faculty of Life Science, Swiss Federal Institute of Technology of Lausanne (EPFL), chemin des mines 9, 1202 Geneva, Switzerland
| | - Giulio Rognini
- Center for Neuroprosthetics, Swiss Federal Institute of Technology of Lausanne (EPFL), chemin des mines 9, 1202 Geneva, Switzerland.,Laboratory of Cognitive Neuroscience, Faculty of Life Science, Swiss Federal Institute of Technology of Lausanne (EPFL), chemin des mines 9, 1202 Geneva, Switzerland
| | - Wietske van der Zwaag
- Biomedical Imaging Research Center, Swiss Federal Institute of Technology of Lausanne (EPFL), Lausanne, Switzerland.,Spinoza Centre for Neuroimaging, Amsterdam, The Netherlands
| | - Maria Iakova
- Département de l'appareil locomoteur, Clinique Romande de Réadaptation SUVA Care, Sion, Switzerland
| | - François Luthi
- Département de l'appareil locomoteur, Clinique Romande de Réadaptation SUVA Care, Sion, Switzerland
| | | | - Todd Kuiken
- Center for Bionic Medicine, Rehabilitation Institute of Chicago, Chicago, IL, USA
| | - Olaf Blanke
- Center for Neuroprosthetics, Swiss Federal Institute of Technology of Lausanne (EPFL), chemin des mines 9, 1202 Geneva, Switzerland.,Laboratory of Cognitive Neuroscience, Faculty of Life Science, Swiss Federal Institute of Technology of Lausanne (EPFL), chemin des mines 9, 1202 Geneva, Switzerland.,Department of Neurology, University Hospital, Geneva, Switzerland
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Marchesotti S, Martuzzi R, Schurger A, Blefari ML, del Millán JR, Bleuler H, Blanke O. Cover Image. Hum Brain Mapp 2017. [DOI: 10.1002/hbm.23634] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Blefari ML, Martuzzi R, Salomon R, Bello-Ruiz J, Herbelin B, Serino A, Blanke O. Bilateral Rolandic operculum processing underlying heartbeat awareness reflects changes in bodily self-consciousness. Eur J Neurosci 2017; 45:1300-1312. [DOI: 10.1111/ejn.13567] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2016] [Revised: 03/23/2017] [Accepted: 03/23/2017] [Indexed: 11/28/2022]
Affiliation(s)
- Maria Laura Blefari
- Center for Neuroprosthetics; École Polytechnique Fédérale de Lausanne; Campus Biotech Chemin des Mines 9 1202 Geneva Switzerland
- Laboratory of Cognitive Neuroscience; Brain Mind Institute; School of Life Sciences; École Polytechnique Fédérale de Lausanne; Lausanne Switzerland
| | - Roberto Martuzzi
- Center for Neuroprosthetics; École Polytechnique Fédérale de Lausanne; Campus Biotech Chemin des Mines 9 1202 Geneva Switzerland
- Laboratory of Cognitive Neuroscience; Brain Mind Institute; School of Life Sciences; École Polytechnique Fédérale de Lausanne; Lausanne Switzerland
- Fondation Campus Biotech Geneva; Geneva Switzerland
| | - Roy Salomon
- Center for Neuroprosthetics; École Polytechnique Fédérale de Lausanne; Campus Biotech Chemin des Mines 9 1202 Geneva Switzerland
- Laboratory of Cognitive Neuroscience; Brain Mind Institute; School of Life Sciences; École Polytechnique Fédérale de Lausanne; Lausanne Switzerland
| | - Javier Bello-Ruiz
- Center for Neuroprosthetics; École Polytechnique Fédérale de Lausanne; Campus Biotech Chemin des Mines 9 1202 Geneva Switzerland
- Laboratory of Cognitive Neuroscience; Brain Mind Institute; School of Life Sciences; École Polytechnique Fédérale de Lausanne; Lausanne Switzerland
| | - Bruno Herbelin
- Center for Neuroprosthetics; École Polytechnique Fédérale de Lausanne; Campus Biotech Chemin des Mines 9 1202 Geneva Switzerland
- Laboratory of Cognitive Neuroscience; Brain Mind Institute; School of Life Sciences; École Polytechnique Fédérale de Lausanne; Lausanne Switzerland
| | - Andrea Serino
- Center for Neuroprosthetics; École Polytechnique Fédérale de Lausanne; Campus Biotech Chemin des Mines 9 1202 Geneva Switzerland
- Laboratory of Cognitive Neuroscience; Brain Mind Institute; School of Life Sciences; École Polytechnique Fédérale de Lausanne; Lausanne Switzerland
- Department of Clinical Neurosciences; University Hospital Lausanne (CHUV); Lausanne Switzerland
| | - Olaf Blanke
- Center for Neuroprosthetics; École Polytechnique Fédérale de Lausanne; Campus Biotech Chemin des Mines 9 1202 Geneva Switzerland
- Laboratory of Cognitive Neuroscience; Brain Mind Institute; School of Life Sciences; École Polytechnique Fédérale de Lausanne; Lausanne Switzerland
- Department of Neurology; Geneva University Hospital; Geneva Switzerland
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8
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Marchesotti S, Martuzzi R, Schurger A, Blefari ML, Del Millán JR, Bleuler H, Blanke O. Cortical and subcortical mechanisms of brain-machine interfaces. Hum Brain Mapp 2017; 38:2971-2989. [PMID: 28321973 DOI: 10.1002/hbm.23566] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2016] [Revised: 02/28/2017] [Accepted: 03/03/2017] [Indexed: 01/06/2023] Open
Abstract
Technical advances in the field of Brain-Machine Interfaces (BMIs) enable users to control a variety of external devices such as robotic arms, wheelchairs, virtual entities and communication systems through the decoding of brain signals in real time. Most BMI systems sample activity from restricted brain regions, typically the motor and premotor cortex, with limited spatial resolution. Despite the growing number of applications, the cortical and subcortical systems involved in BMI control are currently unknown at the whole-brain level. Here, we provide a comprehensive and detailed report of the areas active during on-line BMI control. We recorded functional magnetic resonance imaging (fMRI) data while participants controlled an EEG-based BMI inside the scanner. We identified the regions activated during BMI control and how they overlap with those involved in motor imagery (without any BMI control). In addition, we investigated which regions reflect the subjective sense of controlling a BMI, the sense of agency for BMI-actions. Our data revealed an extended cortical-subcortical network involved in operating a motor-imagery BMI. This includes not only sensorimotor regions but also the posterior parietal cortex, the insula and the lateral occipital cortex. Interestingly, the basal ganglia and the anterior cingulate cortex were involved in the subjective sense of controlling the BMI. These results inform basic neuroscience by showing that the mechanisms of BMI control extend beyond sensorimotor cortices. This knowledge may be useful for the development of BMIs that offer a more natural and embodied feeling of control for the user. Hum Brain Mapp 38:2971-2989, 2017. © 2017 Wiley Periodicals, Inc.
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Affiliation(s)
- Silvia Marchesotti
- Laboratory of Cognitive Neuroscience, School of Life Sciences, Ecole Polytechnique Fédérale de Lausanne, Geneva, Switzerland.,Center for Neuroprosthetics, Ecole Polytechnique Fédérale de Lausanne, Geneva, Switzerland.,Laboratory of Robotic Systems, School of Engineering, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Roberto Martuzzi
- Laboratory of Cognitive Neuroscience, School of Life Sciences, Ecole Polytechnique Fédérale de Lausanne, Geneva, Switzerland.,Center for Neuroprosthetics, Ecole Polytechnique Fédérale de Lausanne, Geneva, Switzerland.,Fondation Campus Biotech Geneva, Geneva, Switzerland
| | - Aaron Schurger
- Laboratory of Cognitive Neuroscience, School of Life Sciences, Ecole Polytechnique Fédérale de Lausanne, Geneva, Switzerland.,Center for Neuroprosthetics, Ecole Polytechnique Fédérale de Lausanne, Geneva, Switzerland.,Defitech Chair in Brain-Machine Interface, School of Engineering, Ecole Polytechnique Fédérale de Lausanne, Geneva, Switzerland.,Cognitive Neuroimaging Unit, NeuroSpin Research Center, INSERM, Gif-Sur-Yvette, France
| | - Maria Laura Blefari
- Laboratory of Cognitive Neuroscience, School of Life Sciences, Ecole Polytechnique Fédérale de Lausanne, Geneva, Switzerland.,Center for Neuroprosthetics, Ecole Polytechnique Fédérale de Lausanne, Geneva, Switzerland.,Defitech Chair in Brain-Machine Interface, School of Engineering, Ecole Polytechnique Fédérale de Lausanne, Geneva, Switzerland
| | - José R Del Millán
- Center for Neuroprosthetics, Ecole Polytechnique Fédérale de Lausanne, Geneva, Switzerland.,Defitech Chair in Brain-Machine Interface, School of Engineering, Ecole Polytechnique Fédérale de Lausanne, Geneva, Switzerland
| | - Hannes Bleuler
- Laboratory of Robotic Systems, School of Engineering, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Olaf Blanke
- Laboratory of Cognitive Neuroscience, School of Life Sciences, Ecole Polytechnique Fédérale de Lausanne, Geneva, Switzerland.,Center for Neuroprosthetics, Ecole Polytechnique Fédérale de Lausanne, Geneva, Switzerland.,Department of Neurology, University Hospital, Geneva, Switzerland
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Mekkaoui C, Metellus P, Kostis WJ, Martuzzi R, Pereira FR, Beregi JP, Reese TG, Constable TR, Jackowski MP. Diffusion Tensor Imaging in Patients with Glioblastoma Multiforme Using the Supertoroidal Model. PLoS One 2016; 11:e0146693. [PMID: 26761637 PMCID: PMC4711969 DOI: 10.1371/journal.pone.0146693] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2015] [Accepted: 12/21/2015] [Indexed: 11/18/2022] Open
Abstract
Purpose Diffusion Tensor Imaging (DTI) is a powerful imaging technique that has led to improvements in the diagnosis and prognosis of cerebral lesions and neurosurgical guidance for tumor resection. Traditional tensor modeling, however, has difficulties in differentiating tumor-infiltrated regions and peritumoral edema. Here, we describe the supertoroidal model, which incorporates an increase in surface genus and a continuum of toroidal shapes to improve upon the characterization of Glioblastoma multiforme (GBM). Materials and Methods DTI brain datasets of 18 individuals with GBM and 18 normal subjects were acquired using a 3T scanner. A supertoroidal model of the diffusion tensor and two new diffusion tensor invariants, one to evaluate diffusivity, the toroidal volume (TV), and one to evaluate anisotropy, the toroidal curvature (TC), were applied and evaluated in the characterization of GBM brain tumors. TV and TC were compared with the mean diffusivity (MD) and fractional anisotropy (FA) indices inside the tumor, surrounding edema, as well as contralateral to the lesions, in the white matter (WM) and gray matter (GM). Results The supertoroidal model enhanced the borders between tumors and surrounding structures, refined the boundaries between WM and GM, and revealed the heterogeneity inherent to tumor-infiltrated tissue. Both MD and TV demonstrated high intensities in the tumor, with lower values in the surrounding edema, which in turn were higher than those of unaffected brain parenchyma. Both TC and FA were effective in revealing the structural degradation of WM tracts. Conclusions Our findings indicate that the supertoroidal model enables effective tensor visualization as well as quantitative scalar maps that improve the understanding of the underlying tissue structure properties. Hence, this approach has the potential to enhance diagnosis, preoperative planning, and intraoperative image guidance during surgical management of brain lesions.
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Affiliation(s)
- Choukri Mekkaoui
- Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Athinoula A. Martinos Center for Biomedical Imaging, Boston, MA, United States of America
- * E-mail:
| | - Philippe Metellus
- Department of Neurosurgery, Hôpital de la Timone Adultes Marseille, Marseille, Bouches-du-Rhône, France
| | - William J. Kostis
- Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Athinoula A. Martinos Center for Biomedical Imaging, Boston, MA, United States of America
- Rutgers Robert Wood Johnson Medical School, New Brunswick, NJ, United States of America
| | - Roberto Martuzzi
- Laboratory of Cognitive Neuroscience, Brain Mind Institute, School of Life Sciences, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Fabricio R. Pereira
- Department of Radiology, University Hospital Center of Nîmes and Research Team EA 2415, Nîmes, Gard, France
| | - Jean-Paul Beregi
- Department of Radiology, University Hospital Center of Nîmes and Research Team EA 2415, Nîmes, Gard, France
| | - Timothy G. Reese
- Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Athinoula A. Martinos Center for Biomedical Imaging, Boston, MA, United States of America
| | - Todd R. Constable
- Department of Diagnostic Radiology, Yale University School of Medicine, Magnetic Resonance Research Center, New Haven, CT, United States of America
| | - Marcel P. Jackowski
- Department of Computer Science, Institute of Mathematics and Statistics, University of São Paulo, São Paulo, Brazil
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van der Zwaag W, Gruetter R, Martuzzi R. Stroking or Buzzing? A Comparison of Somatosensory Touch Stimuli Using 7 Tesla fMRI. PLoS One 2015; 10:e0134610. [PMID: 26285027 PMCID: PMC4540472 DOI: 10.1371/journal.pone.0134610] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2015] [Accepted: 07/11/2015] [Indexed: 11/18/2022] Open
Abstract
Studying body representations in the brain helps us to understand how we humans relate to our own bodies. The in vivo mapping of the somatosensory cortex, where these representations are found, is greatly facilitated by the high spatial resolution and high sensitivity to brain activation available at ultra-high field. In this study, the use of different stimulus types for somatotopic mapping of the digits at ultra-high field, specifically manual stroking and mechanical stimulation, was compared in terms of sensitivity and specificity of the brain responses. Larger positive responses in digit regions of interest were found for manual stroking than for mechanical stimulation, both in terms of average and maximum t-value and in terms of number of voxels with significant responses to the tactile stimulation. Responses to manual stroking were higher throughout the entire post-central sulcus, but the difference was especially large on its posterior wall, i.e. in Brodmann area 2. During mechanical stimulation, cross-digit responses were more negative than during manual stroking, possibly caused by a faster habituation to the stimulus. These differences indicate that manual stroking is a highly suitable stimulus for fast somatotopic mapping procedures, especially if Brodmann area 2 is of interest.
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Affiliation(s)
- Wietske van der Zwaag
- Centre d’Imagerie Biomédicale (CIBM), École Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
- Spinoza Centre for Neuroimaging, Royal Netherlands Academy of Arts and Sciences (KNAW), Amsterdam, Netherlands
- * E-mail:
| | - Rolf Gruetter
- Centre d’Imagerie Biomédicale (CIBM), École Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
- Department of Radiology, University Hospital, Lausanne, Switzerland
- Department of Radiology, University Hospital, Geneva, Switzerland
| | - Roberto Martuzzi
- Center for Neuroprosthetics, School of Life Sciences, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
- Laboratory of Cognitive Neuroscience, Brain Mind Institute, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
- Fondation Campus Biotech Geneva, Geneva, Switzerland
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11
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Murray MM, Thelen A, Thut G, Romei V, Martuzzi R, Matusz PJ. The multisensory function of the human primary visual cortex. Neuropsychologia 2015; 83:161-169. [PMID: 26275965 DOI: 10.1016/j.neuropsychologia.2015.08.011] [Citation(s) in RCA: 107] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2015] [Revised: 08/08/2015] [Accepted: 08/10/2015] [Indexed: 01/20/2023]
Abstract
It has been nearly 10 years since Ghazanfar and Schroeder (2006) proposed that the neocortex is essentially multisensory in nature. However, it is only recently that sufficient and hard evidence that supports this proposal has accrued. We review evidence that activity within the human primary visual cortex plays an active role in multisensory processes and directly impacts behavioural outcome. This evidence emerges from a full pallet of human brain imaging and brain mapping methods with which multisensory processes are quantitatively assessed by taking advantage of particular strengths of each technique as well as advances in signal analyses. Several general conclusions about multisensory processes in primary visual cortex of humans are supported relatively solidly. First, haemodynamic methods (fMRI/PET) show that there is both convergence and integration occurring within primary visual cortex. Second, primary visual cortex is involved in multisensory processes during early post-stimulus stages (as revealed by EEG/ERP/ERFs as well as TMS). Third, multisensory effects in primary visual cortex directly impact behaviour and perception, as revealed by correlational (EEG/ERPs/ERFs) as well as more causal measures (TMS/tACS). While the provocative claim of Ghazanfar and Schroeder (2006) that the whole of neocortex is multisensory in function has yet to be demonstrated, this can now be considered established in the case of the human primary visual cortex.
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Affiliation(s)
- Micah M Murray
- The Laboratory for Investigative Neurophysiology (The LINE), Neuropsychology and Neurorehabilitation Service and Department of Radiology, University Hospital Center and University of Lausanne, Lausanne, Switzerland; EEG Brain Mapping Core, Center for Biomedical Imaging (CIBM) of Lausanne and Geneva, Lausanne, Switzerland; Department of Hearing and Speech Sciences, Vanderbilt University Medical Center, Nashville, TN, USA.
| | - Antonia Thelen
- Department of Hearing and Speech Sciences, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Gregor Thut
- Centre for Cognitive Neuroimaging, Institute of Neuroscience and Psychology, University of Glasgow, Glasgow G12 8QB, United Kingdom
| | - Vincenzo Romei
- Centre for Brain Science, Department of Psychology, University of Essex, Colchester, United Kingdom
| | - Roberto Martuzzi
- Laboratory of Cognitive Neuroscience, Brain-Mind Institute, Ecole Polytechnique Fédérale de Lausanne, Switzerland
| | - Pawel J Matusz
- The Laboratory for Investigative Neurophysiology (The LINE), Neuropsychology and Neurorehabilitation Service and Department of Radiology, University Hospital Center and University of Lausanne, Lausanne, Switzerland; Attention, Brain, and Cognitive Development Group, Department of Experimental Psychology, University of Oxford, United Kingdom.
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Martuzzi R, van der Zwaag W, Dieguez S, Serino A, Gruetter R, Blanke O. Distinct contributions of Brodmann areas 1 and 2 to body ownership. Soc Cogn Affect Neurosci 2015; 10:1449-59. [PMID: 25809404 DOI: 10.1093/scan/nsv031] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2014] [Accepted: 03/19/2015] [Indexed: 11/13/2022] Open
Abstract
Although body ownership--i.e. the feeling that our bodies belong to us--modulates activity within the primary somatosensory cortex (S1), it is still unknown whether this modulation occurs within a somatotopically defined portion of S1. We induced an illusory feeling of ownership for another person's finger by asking participants to hold their palm against another person's palm and to stroke the two joined index fingers with the index and thumb of their other hand. This illusion (numbness illusion) does not occur if the stroking is performed asynchronously or by the other person. We combined this somatosensory paradigm with ultra-high field functional magnetic resonance imaging finger mapping to study whether illusory body ownership modulates activity within different finger-specific areas of S1. The results revealed that the numbness illusion is associated with activity in Brodmann area (BA) 1 within the representation of the finger stroking the other person's finger and in BA 2 contralateral to the stroked finger. These results show that changes in bodily experience modulate the activity within certain subregions of S1, with a different finger-topographical selectivity between the representations of the stroking and of the stroked hand, and reveal that the high degree of somatosensory specialization in S1 extends to bodily self-consciousness.
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Affiliation(s)
- Roberto Martuzzi
- Center for Neuroprosthetics, School of Life Sciences, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland, Laboratory of Cognitive Neuroscience, Brain Mind Institute, School of Life Sciences, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland,
| | - Wietske van der Zwaag
- Centre d'Imagerie Biomédical de Lausanne, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
| | - Sebastian Dieguez
- Laboratory of Cognitive Neuroscience, Brain Mind Institute, School of Life Sciences, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland, Laboratory for Cognitive and Neurological Sciences, Neurology Unit, Department of Medicine, Faculty of Sciences, University of Fribourg, Fribourg, Switzerland, and
| | - Andrea Serino
- Center for Neuroprosthetics, School of Life Sciences, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland, Laboratory of Cognitive Neuroscience, Brain Mind Institute, School of Life Sciences, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
| | - Rolf Gruetter
- Centre d'Imagerie Biomédical de Lausanne, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
| | - Olaf Blanke
- Center for Neuroprosthetics, School of Life Sciences, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland, Laboratory of Cognitive Neuroscience, Brain Mind Institute, School of Life Sciences, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland, Department of Neurology, University Hospital, Geneva, Switzerland
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Abstract
Several brain regions are important for processing self-location and first-person perspective, two important aspects of bodily self-consciousness. However, the interplay between these regions has not been clarified. In addition, while self-location and first-person perspective in healthy subjects are associated with bilateral activity in temporoparietal junction (TPJ), disturbed self-location and first-person perspective result from damage of only the right TPJ. Identifying the involved brain network and understanding the role of hemispheric specializations in encoding self-location and first-person perspective, will provide important information on system-level interactions neurally mediating bodily self-consciousness. Here, we used functional connectivity and showed that right and left TPJ are bilaterally connected to supplementary motor area, ventral premotor cortex, insula, intraparietal sulcus and occipitotemporal cortex. Furthermore, the functional connectivity between right TPJ and right insula had the highest selectivity for changes in self-location and first-person perspective. Finally, functional connectivity revealed hemispheric differences showing that self-location and first-person perspective modulated the connectivity between right TPJ, right posterior insula, and right supplementary motor area, and between left TPJ and right anterior insula. The present data extend previous evidence on healthy populations and clinical observations in neurological deficits, supporting a bilateral, but right-hemispheric dominant, network for bodily self-consciousness.
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Affiliation(s)
- Silvio Ionta
- Center for Neuroprosthetics, School of Life Sciences, École Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland; Laboratory of Cognitive Neuroscience, Brain-Mind Institute, School of Life Sciences, Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland; and Department of Neurology, University Hospital, 1211 Geneva, Switzerland Center for Neuroprosthetics, School of Life Sciences, École Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland; Laboratory of Cognitive Neuroscience, Brain-Mind Institute, School of Life Sciences, Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland; and Department of Neurology, University Hospital, 1211 Geneva, Switzerland
| | - Roberto Martuzzi
- Center for Neuroprosthetics, School of Life Sciences, École Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland; Laboratory of Cognitive Neuroscience, Brain-Mind Institute, School of Life Sciences, Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland; and Department of Neurology, University Hospital, 1211 Geneva, Switzerland Center for Neuroprosthetics, School of Life Sciences, École Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland; Laboratory of Cognitive Neuroscience, Brain-Mind Institute, School of Life Sciences, Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland; and Department of Neurology, University Hospital, 1211 Geneva, Switzerland
| | - Roy Salomon
- Center for Neuroprosthetics, School of Life Sciences, École Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland; Laboratory of Cognitive Neuroscience, Brain-Mind Institute, School of Life Sciences, Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland; and Department of Neurology, University Hospital, 1211 Geneva, Switzerland Center for Neuroprosthetics, School of Life Sciences, École Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland; Laboratory of Cognitive Neuroscience, Brain-Mind Institute, School of Life Sciences, Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland; and Department of Neurology, University Hospital, 1211 Geneva, Switzerland
| | - Olaf Blanke
- Center for Neuroprosthetics, School of Life Sciences, École Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland; Laboratory of Cognitive Neuroscience, Brain-Mind Institute, School of Life Sciences, Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland; and Department of Neurology, University Hospital, 1211 Geneva, Switzerland Center for Neuroprosthetics, School of Life Sciences, École Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland; Laboratory of Cognitive Neuroscience, Brain-Mind Institute, School of Life Sciences, Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland; and Department of Neurology, University Hospital, 1211 Geneva, Switzerland Center for Neuroprosthetics, School of Life Sciences, École Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland; Laboratory of Cognitive Neuroscience, Brain-Mind Institute, School of Life Sciences, Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland; and Department of Neurology, University Hospital, 1211 Geneva, Switzerland
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Pfeiffer C, Lopez C, Schmutz V, Duenas JA, Martuzzi R, Blanke O. Multisensory origin of the subjective first-person perspective: visual, tactile, and vestibular mechanisms. PLoS One 2013; 8:e61751. [PMID: 23630611 PMCID: PMC3632612 DOI: 10.1371/journal.pone.0061751] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2012] [Accepted: 03/13/2013] [Indexed: 11/25/2022] Open
Abstract
In three experiments we investigated the effects of visuo-tactile and visuo-vestibular conflict about the direction of gravity on three aspects of bodily self-consciousness: self-identification, self-location, and the experienced direction of the first-person perspective. Robotic visuo-tactile stimulation was administered to 78 participants in three experiments. Additionally, we presented participants with a virtual body as seen from an elevated and downward-directed perspective while they were lying supine and were therefore receiving vestibular and postural cues about an upward-directed perspective. Under these conditions, we studied the effects of different degrees of visuo-vestibular conflict, repeated measurements during illusion induction, and the relationship to a classical measure of visuo-vestibular integration. Extending earlier findings on experimentally induced changes in bodily self-consciousness, we show that self-identification does not depend on the experienced direction of the first-person perspective, whereas self-location does. Changes in bodily self-consciousness depend on visual gravitational signals. Individual differences in the experienced direction of first-person perspective correlated with individual differences in visuo-vestibular integration. Our data reveal important contributions of visuo-vestibular gravitational cues to bodily self-consciousness. In particular we show that the experienced direction of the first-person perspective depends on the integration of visual, vestibular, and tactile signals, as well as on individual differences in idiosyncratic visuo-vestibular strategies.
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Affiliation(s)
- Christian Pfeiffer
- Center for Neuroprosthetics, School of Life Sciences, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
- Laboratory of Cognitive Neuroscience, Brain Mind Institute, School of Life Sciences, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Christophe Lopez
- Laboratoire de Neurosciences Intégratives et Adaptatives, UMR 7260, Centre National de la Recherche Scientifique and Aix-Marseille Université, Marseille, France
| | - Valentin Schmutz
- Center for Neuroprosthetics, School of Life Sciences, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
- Laboratory of Cognitive Neuroscience, Brain Mind Institute, School of Life Sciences, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Julio Angel Duenas
- Rehabilitation Engineering Lab, Institute for Robotics and Intelligent Systems, Eidgenössische Technische Hochschule Zürich, Zürich, Switzerland
| | - Roberto Martuzzi
- Center for Neuroprosthetics, School of Life Sciences, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
- Laboratory of Cognitive Neuroscience, Brain Mind Institute, School of Life Sciences, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Olaf Blanke
- Center for Neuroprosthetics, School of Life Sciences, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
- Laboratory of Cognitive Neuroscience, Brain Mind Institute, School of Life Sciences, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
- Department of Neurology, University Hospital Geneva, Geneva, Switzerland
- * E-mail:
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Martuzzi R, van der Zwaag W, Farthouat J, Gruetter R, Blanke O. Human finger somatotopy in areas 3b, 1, and 2: a 7T fMRI study using a natural stimulus. Hum Brain Mapp 2012; 35:213-26. [PMID: 22965769 DOI: 10.1002/hbm.22172] [Citation(s) in RCA: 146] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2011] [Revised: 12/23/2011] [Accepted: 07/10/2012] [Indexed: 11/07/2022] Open
Abstract
To study the properties of human primary somatosensory (S1) cortex as well as its role in cognitive and social processes, it is necessary to noninvasively localize the cortical representations of the body. Being arguably the most relevant body parts for tactile exploration, cortical representations of fingers are of particular interest. The aim of the present study was to investigate the cortical representation of individual fingers (D1-D5), using human touch as a stimulus. Utilizing the high BOLD sensitivity and spatial resolution at 7T, we found that each finger is represented within three subregions of S1 in the postcentral gyrus. Within each of these three areas, the fingers are sequentially organized (from D1 to D5) in a somatotopic manner. Therefore, these finger representations likely reflect distinct activations of BAs 3b, 1, and 2, similar to those described in electrophysiological work in non-human primates. Quantitative analysis of the local BOLD responses revealed that within BA3b, each finger representation is specific to its own stimulation without any cross-finger responsiveness. This finger response selectivity was less prominent in BA 1 and in BA 2. A test-retest procedure highlighted the reproducibility of the results and the robustness of the method for BA 3b. Finally, the representation of the thumb was enlarged compared to the other fingers within BAs 1 and 2. These findings extend previous human electrophysiological and neuroimaging data but also reveal differences in the functional organization of S1 in human and nonhuman primates.
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Affiliation(s)
- Roberto Martuzzi
- Laboratory of Cognitive Neuroscience, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland; Center for Neuroprosthetics, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
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Abstract
PURPOSE In planning epilepsy surgery, it is important to be able to assess the likelihood of success of surgery for each patient so that the possible risk and benefit can be properly considered. In this study, functional connectivity was investigated as a means for predicting surgical outcome from the preoperative functional magnetic resonance imaging (fMRI) of epilepsy patients. METHODS Resting-state simultaneous electroencephalography (EEG)-fMRI data were collected from 18 patients with intractable epilepsy before surgery and from 14 healthy subjects. For each patient, EEG-spike correlated fMRI analysis was performed and an activation cluster that overlapped the most with the planned resection area for each patient was chosen as the seed for the functional connectivity analysis. After the functional connectivity maps were computed, laterality indices of functional connectivity were contrasted between patients who had seizures after surgeries (seizure-recurrence group) and those who did not have them for at least a year (seizure-free group). KEY FINDINGS Patients in the seizure-recurrence group had less-lateralized functional connectivity than patients in the seizure-free group (t(16) = 2.3, after control subtracted and Fisher transformed, p < 0.05, two-tailed). SIGNIFICANCE This study suggests the potential for using preoperative fMRI connectivity analysis as a predictive outcome measure. If confirmed by further research, a high laterality will be an important addition to the other predictors of better surgical outcome such as febrile seizures, mesial temporal sclerosis, tumors, abnormal MRI, and EEG/MRI concordance.
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Affiliation(s)
- Michiro Negishi
- Department of Diagnostic Radiology, Yale University School of Medicine, New Haven, Connecticut 06520-8043, USA.
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Martuzzi R, Ramani R, Qiu M, Shen X, Papademetris X, Constable RT. A whole-brain voxel based measure of intrinsic connectivity contrast reveals local changes in tissue connectivity with anesthetic without a priori assumptions on thresholds or regions of interest. Neuroimage 2011; 58:1044-50. [PMID: 21763437 DOI: 10.1016/j.neuroimage.2011.06.075] [Citation(s) in RCA: 111] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2010] [Revised: 05/25/2011] [Accepted: 06/25/2011] [Indexed: 11/28/2022] Open
Abstract
The analysis of spontaneous fluctuations of functional magnetic resonance imaging (fMRI) signals has recently gained attention as a powerful tool for investigating brain circuits in a non-invasive manner. Correlation-based connectivity analysis investigates the correlations of spontaneous fluctuations of the fMRI signal either between a single seed region of interest (ROI) and the rest of the brain or between multiple ROIs. To do this, a priori knowledge is required for defining the ROI(s) and without such knowledge functional connectivity fMRI cannot be used as an exploratory tool for investigating the functional organization of the brain and its modulation under different conditions. In this work we examine two indices that provide voxel based maps reflecting the intrinsic connectivity contrast (ICC) of individual tissue elements without the need for defining ROIs and hence require no a priori information or assumptions. These voxel based ICC measures can also be used to delineate regions of interest for further functional or network analyses. The indices were applied to the study of sevoflurane anesthesia-induced alterations in intrinsic connectivity. In concordance with previous studies, the results show that sevoflurane affects different brain circuits in a heterogeneous manner. In addition ICC analyses revealed changes in regions not previously identified using conventional ROI connectivity analyses, probably because of an inappropriate choice of the ROI in the earlier studies. This work highlights the importance of such voxel based connectivity methodology.
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Affiliation(s)
- Roberto Martuzzi
- Department of Diagnostic Radiology, Yale University School of Medicine, New Haven, CT, USA
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Duenas J, Chapuis D, Pfeiffer C, Martuzzi R, Ionta S, Blanke O, Gassert R. Neuroscience robotics to investigate multisensory integration and bodily awareness. Annu Int Conf IEEE Eng Med Biol Soc 2011; 2011:8348-8352. [PMID: 22256283 DOI: 10.1109/iembs.2011.6092059] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Humans experience the self as localized within their body. This aspect of bodily self-consciousness can be experimentally manipulated by exposing individuals to conflicting multisensory input, or can be abnormal following focal brain injury. Recent technological developments helped to unravel some of the mechanisms underlying multisensory integration and self-location, but the neural underpinnings are still under investigation, and the manual application of stimuli resulted in large variability difficult to control. This paper presents the development and evaluation of an MR-compatible stroking device capable of presenting moving tactile stimuli to both legs and the back of participants lying on a scanner bed while acquiring functional neuroimaging data. The platform consists of four independent stroking devices with a travel of 16-20 cm and a maximum stroking velocity of 15 cm/s, actuated over non-magnetic ultrasonic motors. Complemented with virtual reality, this setup provides a unique research platform allowing to investigate multisensory integration and its effects on self-location under well-controlled experimental conditions. The MR-compatibility of the system was evaluated in both a 3 and a 7 Tesla scanner and showed negligible interference with brain imaging. In a preliminary study using a prototype device with only one tactile stimulator, fMRI data acquired on 12 healthy participants showed visuo-tactile synchrony-related and body-specific modulations of the brain activity in bilateral temporoparietal cortex.
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Affiliation(s)
- J Duenas
- Rehabilitation Engineering Lab, ETH Zurich, Switzerland
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Cocchi L, Toepel U, De Lucia M, Martuzzi R, Wood SJ, Carter O, Murray MM. Working memory load improves early stages of independent visual processing. Neuropsychologia 2010; 49:92-102. [PMID: 20974157 DOI: 10.1016/j.neuropsychologia.2010.10.021] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2010] [Revised: 10/09/2010] [Accepted: 10/15/2010] [Indexed: 11/19/2022]
Abstract
Increasing evidence suggests that working memory and perceptual processes are dynamically interrelated due to modulating activity in overlapping brain networks. However, the direct influence of working memory on the spatio-temporal brain dynamics of behaviorally relevant intervening information remains unclear. To investigate this issue, subjects performed a visual proximity grid perception task under three different visual-spatial working memory (VSWM) load conditions. VSWM load was manipulated by asking subjects to memorize the spatial locations of 6 or 3 disks. The grid was always presented between the encoding and recognition of the disk pattern. As a baseline condition, grid stimuli were presented without a VSWM context. VSWM load altered both perceptual performance and neural networks active during intervening grid encoding. Participants performed faster and more accurately on a challenging perceptual task under high VSWM load as compared to the low load and the baseline condition. Visual evoked potential (VEP) analyses identified changes in the configuration of the underlying sources in one particular period occurring 160-190 ms post-stimulus onset. Source analyses further showed an occipito-parietal down-regulation concurrent to the increased involvement of temporal and frontal resources in the high VSWM context. Together, these data suggest that cognitive control mechanisms supporting working memory may selectively enhance concurrent visual processing related to an independent goal. More broadly, our findings are in line with theoretical models implicating the engagement of frontal regions in synchronizing and optimizing mnemonic and perceptual resources towards multiple goals.
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Affiliation(s)
- Luca Cocchi
- Melbourne Neuropsychiatry Centre, Department of Psychiatry, The University of Melbourne and Melbourne Health, Australia.
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Mekkaoui C, Jackowski MP, Martuzzi R, Dione DP, Spinale FG, Sinusas AJ. Regional matrix metalloproteinase activation correlates with microstructure diffusion tensor indices post myocardial infarction. J Cardiovasc Magn Reson 2010. [DOI: 10.1186/1532-429x-12-s1-p241] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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De Lucia M, Cocchi L, Martuzzi R, Meuli RA, Clarke S, Murray MM. Perceptual and Semantic Contributions to Repetition Priming of Environmental Sounds. Cereb Cortex 2009; 20:1676-84. [DOI: 10.1093/cercor/bhp230] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Martuzzi R, Ramani R, Qiu M, Rajeevan N, Constable RT. Functional connectivity and alterations in baseline brain state in humans. Neuroimage 2009; 49:823-34. [PMID: 19631277 DOI: 10.1016/j.neuroimage.2009.07.028] [Citation(s) in RCA: 174] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2009] [Revised: 07/10/2009] [Accepted: 07/15/2009] [Indexed: 11/18/2022] Open
Abstract
This work examines the influence of changes in baseline activity on the intrinsic functional connectivity fMRI (fc-fMRI) in humans. Baseline brain activity was altered by inducing anesthesia (sevoflurane end-tidal concentration 1%) in human volunteers and fc-fMRI maps between the pre-anesthetized and anesthetized conditions were compared across different brain networks. We particularly focused on low-level sensory areas (primary somatosensory, visual, and auditory cortices), the thalamus, and pain (insula), memory (hippocampus) circuits, and the default mode network (DMN), the latter three to examine higher-order brain regions. The results indicate that, while fc-fMRI patterns did not significantly differ (p<0.005; 20-voxel cluster threshold) in sensory cortex and in the DMN between the pre- and anesthetized conditions, fc-fMRI in high-order cognitive regions (i.e. memory and pain circuits) was significantly altered by anesthesia. These findings provide further evidence that fc-fMRI reflects intrinsic brain properties, while also demonstrating that 0.5 MAC sevoflurane anesthesia preferentially modulates higher-order connections.
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Affiliation(s)
- Roberto Martuzzi
- Department of Diagnostic Radiology, Yale University School of Medicine, The Anlyan Center, 300 Cedar Street, New Haven, CT 06520-8042, USA.
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Martuzzi R, Rajeevan N, Qiu M, Ramani R, Constable RT. Brain Connectivity Changes Induced by Sevoflurane as Assessed using Intrinsic Connectivity Contrast. Neuroimage 2009. [DOI: 10.1016/s1053-8119(09)70591-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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Qiu M, Martuzzi R, Ramani R, Constable RT. Transient BOLD Responses to Auditory Stimulation during Sevoflurane Anesthesia and Their Implications for fMRI. Neuroimage 2009. [DOI: 10.1016/s1053-8119(09)70933-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
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Martuzzi R, Murray MM, Meuli RA, Thiran JP, Maeder PP, Michel CM, Grave de Peralta Menendez R, Gonzalez Andino SL. Methods for Determining Frequency- and Region-Dependent Relationships Between Estimated LFPs and BOLD Responses in Humans. J Neurophysiol 2009; 101:491-502. [DOI: 10.1152/jn.90335.2008] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The relationship between electrophysiological and functional magnetic resonance imaging (fMRI) signals remains poorly understood. To date, studies have required invasive methods and have been limited to single functional regions and thus cannot account for possible variations across brain regions. Here we present a method that uses fMRI data and singe-trial electroencephalography (EEG) analyses to assess the spatial and spectral dependencies between the blood-oxygenation-level-dependent (BOLD) responses and the noninvasively estimated local field potentials (eLFPs) over a wide range of frequencies (0–256 Hz) throughout the entire brain volume. This method was applied in a study where human subjects completed separate fMRI and EEG sessions while performing a passive visual task. Intracranial LFPs were estimated from the scalp-recorded data using the ELECTRA source model. We compared statistical images from BOLD signals with statistical images of each frequency of the eLFPs. In agreement with previous studies in animals, we found a significant correspondence between LFP and BOLD statistical images in the gamma band (44–78 Hz) within primary visual cortices. In addition, significant correspondence was observed at low frequencies (<14 Hz) and also at very high frequencies (>100 Hz). Effects within extrastriate visual areas showed a different correspondence that not only included those frequency ranges observed in primary cortices but also additional frequencies. Results therefore suggest that the relationship between electrophysiological and hemodynamic signals thus might vary both as a function of frequency and anatomical region.
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Pourtois G, Schwartz S, Spiridon M, Martuzzi R, Vuilleumier P. Object representations for multiple visual categories overlap in lateral occipital and medial fusiform cortex. Cereb Cortex 2008; 19:1806-19. [PMID: 19015371 DOI: 10.1093/cercor/bhn210] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
How representations of visual objects are maintained across changes in viewpoint is a central issue in visual perception. Whether neural processes underlying view-invariant recognition involve distinct subregions within extrastriate visual cortex for distinct categories of visual objects remains unresolved. We used event-related functional magnetic resonance imaging in 16 healthy volunteers to map visual cortical areas responding to a large set (156) of exemplars from 3 object categories (faces, houses, and chairs), each repeated once after a variable time lag (3-7 intervening stimuli). Exemplars were repeated with the same viewpoint (but different retinal size) or with different viewpoint and size. The task was kept constant across object categories (judging items as "young" vs. "old"). We identified object-selective adaptation effects by comparing neural responses to the first presentation versus repetition of each individual exemplar. We found that exemplar-specific adaptation effects partly overlapped with regions showing category-selective responses (as identified using a separate localizer scan). These included the lateral fusiform gyrus (FG) for faces, parahippocampal gyrus for houses, and lateral occipital complex (LOC) for chairs. In face-selective fusiform gyrus (FG), adaptation effects occurred only for faces repeated with the same viewpoint, but not with a different viewpoint, confirming previous studies using faces only. By contrast, a region in right medial FG, adjacent to but nonoverlapping with the more lateral and face-selective FG, showed repetition effects for faces and to a lesser extent for other objects, regardless of changes in viewpoint or in retinal image-size. Category- and viewpoint-independent repetition effects were also found in bilateral LOC. Our results reveal a common neural substrate in bilateral LOC and right medial FG underlying view-invariant and category-independent recognition for multiple object identities, with only a relative preference for faces in medial FG but no selectivity in LOC.
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Affiliation(s)
- Gilles Pourtois
- Laboratory for Behavioral Neurology and Imaging of Cognition, Department of Neuroscience and Clinic of Neurology, Ghent University, Henri Dunantlaan 2, 9000 Gent, Belgium.
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Hagmann P, Cammoun L, Martuzzi R, Maeder P, Clarke S, Thiran JP, Meuli R. Hand preference and sex shape the architecture of language networks. Hum Brain Mapp 2006; 27:828-35. [PMID: 16541458 PMCID: PMC6871314 DOI: 10.1002/hbm.20224] [Citation(s) in RCA: 81] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
In right-handed subjects, language processing relies predominantly on left hemisphere networks, more so in men than in women, and in right- versus left-handers. Using DT-MRI tractography, we have shown that right-handed men are massively interconnected between the left-hemisphere language areas, whereas the homologous in the right hemisphere are sparse; interhemispheric connections between the language areas and their contralateral homologues are relatively strong. Women and left-handed men have equally strong intrahemispheric connections in both hemispheres, but women have a higher density of interhemispheric connections.
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Affiliation(s)
- Patric Hagmann
- Signal Processing Institute, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland.
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Martuzzi R, Murray MM, Michel CM, Thiran JP, Maeder PP, Clarke S, Meuli RA. Multisensory interactions within human primary cortices revealed by BOLD dynamics. ACTA ACUST UNITED AC 2006; 17:1672-9. [PMID: 16968869 DOI: 10.1093/cercor/bhl077] [Citation(s) in RCA: 175] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
Whether signals from different sensory modalities converge and interact within primary cortices in humans is unresolved, despite emerging evidence in animals. This is partially because of debates concerning the appropriate analyses of functional magnetic resonance imaging (fMRI) data in response to multisensory phenomena. Using event-related fMRI, we observed that simple auditory stimuli (noise bursts) activated primary visual cortices and that simple visual stimuli (checkerboards) activated primary auditory cortices, indicative of multisensory convergence. Moreover, analyses of blood oxygen level-dependent response dynamics revealed facilitation of hemodynamic response peak latencies and slopes for multisensory auditory-visual stimuli versus either unisensory condition, indicative of multisensory interactions within primary sensory cortices. Neural processing at the lowest cortical levels can be modulated by interactions between the senses. Temporal information in fMRI data can reveal these modulations and overcome analytic and interpretational challenges of more traditional procedures. In addition to providing an essential translational link with animal models, these results suggest that longstanding notions of cortical organization need to be revised to include multisensory interactions as an inherent component of functional brain organization.
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Affiliation(s)
- Roberto Martuzzi
- Service de Radiodiagnostic et Radiologie Interventionnelle, Centre Hospitalier Universitaire Vaudois, Lausanne, Switzerland. roberto@
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Martuzzi R, Murray MM, Maeder PP, Fornari E, Thiran JP, Clarke S, Michel CM, Meuli RA. Visuo-motor pathways in humans revealed by event-related fMRI. Exp Brain Res 2005; 170:472-87. [PMID: 16307262 DOI: 10.1007/s00221-005-0232-6] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2004] [Accepted: 09/20/2005] [Indexed: 11/25/2022]
Abstract
Whether different brain networks are involved in generating unimanual responses to a simple visual stimulus presented in the ipsilateral versus contralateral hemifield remains a controversial issue. Visuo-motor routing was investigated with event-related functional magnetic resonance imaging (fMRI) using the Poffenberger reaction time task. A 2 hemifield x 2 response hand design generated the "crossed" and "uncrossed" conditions, describing the spatial relation between these factors. Both conditions, with responses executed by the left or right hand, showed a similar spatial pattern of activated areas, including striate and extrastriate areas bilaterally, SMA, and M1 contralateral to the responding hand. These results demonstrated that visual information is processed bilaterally in striate and extrastriate visual areas, even in the "uncrossed" condition. Additional analyses based on sorting data according to subjects' reaction times revealed differential crossed versus uncrossed activity only for the slowest trials, with response strength in infero-temporal cortices significantly correlating with crossed-uncrossed differences (CUD) in reaction times. Collectively, the data favor a parallel, distributed model of brain activation. The presence of interhemispheric interactions and its consequent bilateral activity is not determined by the crossed anatomic projections of the primary visual and motor pathways. Distinct visuo-motor networks need not be engaged to mediate behavioral responses for the crossed visual field/response hand condition. While anatomical connectivity heavily influences the spatial pattern of activated visuo-motor pathways, behavioral and functional parameters appear to also affect the strength and dynamics of responses within these pathways.
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Affiliation(s)
- Roberto Martuzzi
- Service de Radiodiagnostic et Radiologie Interventionnelle, Center Hospitalier Universitaire Vaudois, rue du Bugnon 46, Lausanne, Switzerland.
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Grave de Peralta Menendez R, Murray MM, Michel CM, Martuzzi R, Gonzalez Andino SL. Corrigendum to “Electrical neuroimaging based on biophysical constraints” [Neuroimage 21 (2004) 527–539]. Neuroimage 2005. [DOI: 10.1016/j.neuroimage.2005.01.023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
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Milan A, Mulatero P, Williams TA, Carra R, Schiavone D, Martuzzi R, Rabbia F, Veglio F. Bradykinin B2 receptor gene (???58T/C) polymorphism influences baroreflex sensitivity in never-treated hypertensive patients. J Hypertens 2005; 23:63-9. [PMID: 15643126 DOI: 10.1097/00004872-200501000-00014] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
BACKGROUND Most evidence currently favours a fundamental role of the autonomic nervous system in the pathogenesis of essential hypertension. Recent studies suggest that about 40% of baroreflex variation, an index of cardiac autonomic control, is influenced by genetic factors. METHODS AND RESULTS The aim of this study was to investigate the effect of a common polymorphic variant of the bradykinin B2 receptor gene (B2R; -58T/C) on the autonomic regulation of baroreflex sensitivity (BRS) in 129 mild-moderate never-treated hypertensive patients. No significant differences were found for clinical and biochemical parameters among genotypes. BRS increased with the number of B2R T alleles. B2R genotype was a strong independent predictor of BRS, accounting for 12% of its variation. We suggest that a decrease in the transcription of the bradykinin B2R gene in the presence of the B2R -58C allele could reduce BRS via the diminished effect of bradykinin. CONCLUSIONS B2R genotype can explain part of the BRS variation that is unaccounted for by simple anthropometric variables and common risk factors.
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Affiliation(s)
- Alberto Milan
- Department of Medicine and Experimental Oncology, Hypertension Unit, University of Torino, Italy
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Grave de Peralta Menendez R, Murray MM, Michel CM, Martuzzi R, Gonzalez Andino SL. Electrical neuroimaging based on biophysical constraints. Neuroimage 2004; 21:527-39. [PMID: 14980555 DOI: 10.1016/j.neuroimage.2003.09.051] [Citation(s) in RCA: 287] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2003] [Revised: 09/25/2003] [Accepted: 09/26/2003] [Indexed: 11/23/2022] Open
Abstract
This paper proposes and implements biophysical constraints to select a unique solution to the bioelectromagnetic inverse problem. It first shows that the brain's electric fields and potentials are predominantly due to ohmic currents. This serves to reformulate the inverse problem in terms of a restricted source model permitting noninvasive estimations of Local Field Potentials (LFPs) in depth from scalp-recorded data. Uniqueness in the solution is achieved by a physically derived regularization strategy that imposes a spatial structure on the solution based upon the physical laws that describe electromagnetic fields in biological media. The regularization strategy and the source model emulate the properties of brain activity's actual generators. This added information is independent of both the recorded data and head model and suffices for obtaining a unique solution compatible with and aimed at analyzing experimental data. The inverse solution's features are evaluated with event-related potentials (ERPs) from a healthy subject performing a visuo-motor task. Two aspects are addressed: the concordance between available neurophysiological evidence and inverse solution results, and the functional localization provided by fMRI data from the same subject under identical experimental conditions. The localization results are spatially and temporally concordant with experimental evidence, and the areas detected as functionally activated in both imaging modalities are similar, providing indices of localization accuracy. We conclude that biophysically driven inverse solutions offer a novel and reliable possibility for studying brain function with the temporal resolution required to advance our understanding of the brain's functional networks.
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