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Liu Y, Peng X, Lin C, Liu D, Sun Y, Huang F, Liu T, Xiao L, Wei X, Wang K, Chen Z, Rong L. Fractional amplitude of low-frequency fluctuation and voxel-mirrored homotopic connectivity in patients with persistent postural-perceptual dizziness: resting-state functional magnetic resonance imaging study. Brain Connect 2024. [PMID: 38623770 DOI: 10.1089/brain.2023.0071] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/17/2024] Open
Abstract
PURPOSE Persistent postural-perception dizziness (PPPD) is a chronic subjective form of dizziness characterized by the exacerbation of dizziness with active or passive movement, complex visual stimuli, and upright posture. Therefore, we aimed to analyze the resting-state functional magnetic resonance imaging (fMRI) in patients with PPPD using fractional amplitude of low-frequency fluctuation (fALFF) and voxel-mirrored homotopic connectivity (VMHC) and evaluate the correlation between abnormal regions in the brain and clinical features to investigate the pathogenesis of PPPD. METHODS Thirty patients with PPPD (19 females and 11 males) and 30 healthy controls (HC) (18 females and 12 males) were closely matched for age and sex. The fALFF and VMHC methods were used to investigate differences in fMRI (BOLD sequences) between the PPPD and HC groups and to explore the associations between areas of functional abnormality and clinical characteristics (Dizziness, Anxiety, Depression, and Duration). RESULT Compared to the HC group, patients with PPPD displayed different functional change patterns, with increased fALFF in the right precuneus and decreased VMHC in the bilateral precuneus. Additionally, patients with PPPD had a positive correlation between precuneus fALFF values and dizziness handicap inventory (DHI) scores, and a negative correlation between VMHC values and the disease duration. CONCLUSIONS Precuneus dysfunction was observed in patients with PPPD. The fALFF values correlated with the degree of dizziness in PPPD, and changes in VMHC values were associated with the duration of dizziness, suggesting that fMRI changes in the precuneus of patients could be used as a potential imaging marker for PPPD.
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Affiliation(s)
- Yueji Liu
- The Second Affiliated Hospital of Xuzhou Medical University, 608493, Xuzhou, China;
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Chen Z, Cai Y, Xiao L, Wei XE, Liu Y, Lin C, Liu D, Liu H, Rong L. Increased functional connectivity between default mode network and visual network potentially correlates with duration of residual dizziness in patients with benign paroxysmal positional vertigo. Front Neurol 2024; 15:1363869. [PMID: 38500812 PMCID: PMC10944895 DOI: 10.3389/fneur.2024.1363869] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2023] [Accepted: 02/23/2024] [Indexed: 03/20/2024] Open
Abstract
Objective To assess changes in static and dynamic functional network connectivity (sFNC and dFNC) and explore their correlations with clinical features in benign paroxysmal positional vertigo (BPPV) patients with residual dizziness (RD) after successful canalith repositioning maneuvers (CRM) using resting-state fMRI. Methods We studied resting-state fMRI data from 39 BPPV patients with RD compared to 38 BPPV patients without RD after successful CRM. Independent component analysis and methods of sliding window and k-means clustering were adopted to investigate the changes in dFNC and sFNC between the two groups. Additionally, temporal features and meta-states were compared between the two groups. Furthermore, the associations between fMRI results and clinical characteristics were analyzed using Pearson's partial correlation analysis. Results Compared with BPPV patients without RD, patients with RD had longer duration of BPPV and higher scores of dizziness handicap inventory (DHI) before successful CRM. BPPV patients with RD displayed no obvious abnormal sFNC compared to patients without RD. In the dFNC analysis, patients with RD showed increased FNC between default mode network (DMN) and visual network (VN) in state 4, the FNC between DMN and VN was positively correlated with the duration of RD. Furthermore, we found increased mean dwell time (MDT) and fractional windows (FW) in state 1 but decreased MDT and FW in state 3 in BPPV patients with RD. The FW of state 1 was positively correlated with DHI score before CRM, the MDT and FW of state 3 were negatively correlated with the duration of BPPV before CRM in patients with RD. Additionally, compared with patients without RD, patients with RD showed decreased number of states and state span. Conclusion The occurrence of RD might be associated with increased FNC between DMN and VN, and the increased FNC between DMN and VN might potentially correlate with the duration of RD symptoms. In addition, we found BPPV patients with RD showed altered global meta-states and temporal features. These findings are helpful for us to better understand the underlying neural mechanisms of RD and potentially contribute to intervention development for BPPV patients with RD.
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Affiliation(s)
- Zhengwei Chen
- Department of Neurology, Second Affiliated Hospital of Xuzhou Medical University, Xuzhou, Jiangsu, China
| | - Yaxian Cai
- Department of Neurology, General Hospital of the Yangtze River Shipping, Wuhan, Hubei, China
| | - Lijie Xiao
- Department of Neurology, Second Affiliated Hospital of Xuzhou Medical University, Xuzhou, Jiangsu, China
| | - Xiu-E Wei
- Department of Neurology, Second Affiliated Hospital of Xuzhou Medical University, Xuzhou, Jiangsu, China
| | - Yueji Liu
- Department of Neurology, Second Affiliated Hospital of Xuzhou Medical University, Xuzhou, Jiangsu, China
| | - Cunxin Lin
- Department of Neurology, Second Affiliated Hospital of Xuzhou Medical University, Xuzhou, Jiangsu, China
- Graduate School of Xuzhou Medical University, Xuzhou, Jiangsu, China
| | - Dan Liu
- Department of Neurology, Second Affiliated Hospital of Xuzhou Medical University, Xuzhou, Jiangsu, China
- Graduate School of Xuzhou Medical University, Xuzhou, Jiangsu, China
| | - Haiyan Liu
- Department of Neurology, Second Affiliated Hospital of Xuzhou Medical University, Xuzhou, Jiangsu, China
| | - Liangqun Rong
- Department of Neurology, Second Affiliated Hospital of Xuzhou Medical University, Xuzhou, Jiangsu, China
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Chen Z, Liu Y, Lin C, Liu D, Xiao L, Liu H, Wei X, Rong L. Altered parietal operculum cortex 2 functional connectivity in benign paroxysmal positional vertigo patients with residual dizziness: A resting-state fMRI study. CNS Neurosci Ther 2024; 30:e14570. [PMID: 38421104 PMCID: PMC10850607 DOI: 10.1111/cns.14570] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2023] [Revised: 11/27/2023] [Accepted: 12/03/2023] [Indexed: 03/02/2024] Open
Abstract
AIMS To investigate changes in functional connectivity (FC) focusing on parietal operculum cortex 2 (OP2) in benign paroxysmal positional vertigo (BPPV) patients with residual dizziness (RD) after successful canalith repositioning procedure (CRP). METHODS High-resolution three-dimensional T1 and resting-state functional magnetic resonance imaging (fMRI) were performed on 55 healthy controls (HCs), 55 BPPV patients with RD, and 55 patients without RD after successful CRP. Seed-based (bilateral OP2) FC was calculated to investigate the changes in FC among the three groups. Additionally, we further explored the associations between abnormal FC and clinical symptoms. RESULTS One-way analysis of covariance showed significant FC differences among the three groups. Post-hoc analysis showed that patients with RD exhibited decreased FC between left OP2 and regions of left angular gyrus (AG), thalamus, precuneus, middle frontal gyrus (MFG), and right cerebellum posterior lobe (CPL) in comparison with HCs. In addition, compared with patients without RD, patients with RD showed decreased FC between left OP2 and regions of left MFG, AG, middle temporal gyrus, and right CPL. Moreover, in patients with RD, the FC between left thalamus and OP2 was negatively correlated with duration of RD, and the FC between left AG and OP2 was negatively correlated with duration of BPPV. CONCLUSION BPPV patients with RD showed reduced FC between brain regions involved in vestibular processing and spatial cognition; These results suggested that BPPV patients with RD might have diminished central processing of vestibular information and impaired spatial cognition.
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Affiliation(s)
- Zhengwei Chen
- Department of NeurologySecond Affiliated Hospital of Xuzhou Medical UniversityXuzhouChina
| | - Yueji Liu
- Department of NeurologySecond Affiliated Hospital of Xuzhou Medical UniversityXuzhouChina
| | - Cunxin Lin
- Department of NeurologySecond Affiliated Hospital of Xuzhou Medical UniversityXuzhouChina
| | - Dan Liu
- Department of NeurologySecond Affiliated Hospital of Xuzhou Medical UniversityXuzhouChina
| | - Lijie Xiao
- Department of NeurologySecond Affiliated Hospital of Xuzhou Medical UniversityXuzhouChina
| | - Haiyan Liu
- Department of NeurologySecond Affiliated Hospital of Xuzhou Medical UniversityXuzhouChina
| | - Xiu‐e Wei
- Department of NeurologySecond Affiliated Hospital of Xuzhou Medical UniversityXuzhouChina
| | - Liangqun Rong
- Department of NeurologySecond Affiliated Hospital of Xuzhou Medical UniversityXuzhouChina
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Arvaniti CK, Brotis AG, Paschalis T, Kapsalaki EZ, Fountas KN. Localization of Vestibular Cortex Using Electrical Cortical Stimulation: A Systematic Literature Review. Brain Sci 2024; 14:75. [PMID: 38248290 PMCID: PMC10813901 DOI: 10.3390/brainsci14010075] [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: 12/20/2023] [Revised: 01/07/2024] [Accepted: 01/09/2024] [Indexed: 01/23/2024] Open
Abstract
The vestibular system plays a fundamental role in body orientation, posture control, and spatial and body motion perception, as well as in gaze and eye movements. We aimed to review the current knowledge regarding the location of the cortical and subcortical areas, implicated in the processing of vestibular stimuli. The search was performed in PubMed and Scopus. We focused on studies reporting on vestibular manifestations after electrical cortical stimulation. A total of 16 studies were finally included. Two main types of vestibular responses were elicited, including vertigo and perception of body movement. The latter could be either rotatory or translational. Electrical stimulation of the temporal structures elicited mainly vertigo, while stimulation of the parietal lobe was associated with perceptions of body movement. Stimulation of the occipital lobe produced vertigo with visual manifestations. There was evidence that the vestibular responses became more robust with increasing current intensity. Low-frequency stimulation proved to be more effective than high-frequency in eliciting vestibular responses. Numerous non-vestibular responses were recorded after stimulation of the vestibular cortex, including somatosensory, viscero-sensory, and emotional manifestations. Newer imaging modalities such as functional MRI (fMRI), Positron Emission Tomography (PET), SPECT, and near infra-red spectroscopy (NIRS) can provide useful information regarding localization of the vestibular cortex.
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Affiliation(s)
- Christina K. Arvaniti
- Department of Neurosurgery, University Hospital of Larissa, Faculty of Medicine, School of Health Sciences, University of Thessaly, 41110 Larissa, Greece; (C.K.A.); (A.G.B.)
| | - Alexandros G. Brotis
- Department of Neurosurgery, University Hospital of Larissa, Faculty of Medicine, School of Health Sciences, University of Thessaly, 41110 Larissa, Greece; (C.K.A.); (A.G.B.)
| | - Thanasis Paschalis
- Department of Neuro-Oncology, Cambridge University Hospital, Cambridge CB4 1GN, UK;
| | - Eftychia Z. Kapsalaki
- Department of Diagnostic Radiology, University Hospital of Larissa, Faculty of Medicine, School of Health Sciences, University of Thessaly, 41100 Larisa, Greece;
- Advanced Diagnostic Institute Euromedica-Encephalos, 15233 Athens, Greece
| | - Kostas N. Fountas
- Department of Neurosurgery, University Hospital of Larissa, Faculty of Medicine, School of Health Sciences, University of Thessaly, 41110 Larissa, Greece; (C.K.A.); (A.G.B.)
- Faculty of Medicine, University of Thessaly, Biopolis, 41110 Larissa, Greece
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Sulpizio V, von Gal A, Galati G, Fattori P, Galletti C, Pitzalis S. Neural sensitivity to translational self- and object-motion velocities. Hum Brain Mapp 2024; 45:e26571. [PMID: 38224544 PMCID: PMC10785198 DOI: 10.1002/hbm.26571] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2023] [Revised: 12/04/2023] [Accepted: 12/07/2023] [Indexed: 01/17/2024] Open
Abstract
The ability to detect and assess world-relative object-motion is a critical computation performed by the visual system. This computation, however, is greatly complicated by the observer's movements, which generate a global pattern of motion on the observer's retina. How the visual system implements this computation is poorly understood. Since we are potentially able to detect a moving object if its motion differs in velocity (or direction) from the expected optic flow generated by our own motion, here we manipulated the relative motion velocity between the observer and the object within a stationary scene as a strategy to test how the brain accomplishes object-motion detection. Specifically, we tested the neural sensitivity of brain regions that are known to respond to egomotion-compatible visual motion (i.e., egomotion areas: cingulate sulcus visual area, posterior cingulate sulcus area, posterior insular cortex [PIC], V6+, V3A, IPSmot/VIP, and MT+) to a combination of different velocities of visually induced translational self- and object-motion within a virtual scene while participants were instructed to detect object-motion. To this aim, we combined individual surface-based brain mapping, task-evoked activity by functional magnetic resonance imaging, and parametric and representational similarity analyses. We found that all the egomotion regions (except area PIC) responded to all the possible combinations of self- and object-motion and were modulated by the self-motion velocity. Interestingly, we found that, among all the egomotion areas, only MT+, V6+, and V3A were further modulated by object-motion velocities, hence reflecting their possible role in discriminating between distinct velocities of self- and object-motion. We suggest that these egomotion regions may be involved in the complex computation required for detecting scene-relative object-motion during self-motion.
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Affiliation(s)
- Valentina Sulpizio
- Department of Cognitive and Motor Rehabilitation and NeuroimagingSanta Lucia Foundation (IRCCS Fondazione Santa Lucia)RomeItaly
- Department of PsychologySapienza UniversityRomeItaly
| | | | - Gaspare Galati
- Department of Cognitive and Motor Rehabilitation and NeuroimagingSanta Lucia Foundation (IRCCS Fondazione Santa Lucia)RomeItaly
- Department of PsychologySapienza UniversityRomeItaly
| | - Patrizia Fattori
- Department of Biomedical and Neuromotor SciencesUniversity of BolognaBolognaItaly
| | - Claudio Galletti
- Department of Biomedical and Neuromotor SciencesUniversity of BolognaBolognaItaly
| | - Sabrina Pitzalis
- Department of Cognitive and Motor Rehabilitation and NeuroimagingSanta Lucia Foundation (IRCCS Fondazione Santa Lucia)RomeItaly
- Department of Movement, Human and Health SciencesUniversity of Rome “Foro Italico”RomeItaly
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Taussig D, Mazzola L, Petrescu AM, Aghakhani N, Bouilleret V, Dorfmüller G, Ferrand-Sorbets S, Herbrecht A, Isnard J. Deep retroinsular and parieto-opercular origin of vestibular symptoms: A stereoelectrocenphalography (SEEG) study. Epilepsy Behav 2023; 149:109509. [PMID: 37935078 DOI: 10.1016/j.yebeh.2023.109509] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/23/2023] [Revised: 10/20/2023] [Accepted: 10/22/2023] [Indexed: 11/09/2023]
Abstract
Several studies have shown that the retroinsular and posterior parietal operculum regions play a central role in vestibular processing. Electrical stimulations performed during stereoelectroencephalography (SEEG) in patients with focal drug-resistant epilepsy could contribute to the analysis of this area. Among the 264 SEEGs performed in both an adult and a paediatric epilepsy surgery centre, we retrospectively identified 24 patients (9%) reporting vertigo during electrical stimulations (ES). In seven of them (29% of patients experiencing vertigo during ES), it was evoked by stimulating the retroinsular region. The reported responses were mostly not rotatory sensations but actually illusions of body, limb or limb segment movement. The involved area is limited. Moreover, two patients reported having the same symptoms at the beginning of their seizures starting in the same region. Our case study confirms the pivotal role of the retroinsular and posterior parietal operculum areas in vestibular responses, and we therefore advise the exploration of this region when patients report an illusion of body movement at the beginning of their seizures.
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Affiliation(s)
- Delphine Taussig
- Université Paris Saclay-APHP, Neurophysiologie et Epileptologie, Le Kremlin Bicêtre, France.
| | - Laure Mazzola
- Neurology Department, University Hospital, Saint-Etienne, France; NeuroPain Lab, Lyon Neuroscience Research Centre, CRNL - INSERM U 1028/CNRS UMR 5292, University of Lyon, Lyon, France
| | - Ana Maria Petrescu
- Université Paris Saclay-APHP, Neurophysiologie et Epileptologie, Le Kremlin Bicêtre, France
| | - Nozar Aghakhani
- Université Paris Saclay-APHP, Neurochirurgie, Le Kremlin Bicêtre, France
| | - Viviane Bouilleret
- Université Paris Saclay-APHP, Neurophysiologie et Epileptologie, Le Kremlin Bicêtre, France; Université Paris-Saclay, CEA, CNRS, Inserm, BioMaps, Orsay, France
| | - Georg Dorfmüller
- Hôpital Fondation Rothschild, Neurochirurgie Pédiatrique, Paris, France
| | | | - Anne Herbrecht
- Université Paris Saclay-APHP, Neurochirurgie, Le Kremlin Bicêtre, France
| | - Jean Isnard
- NeuroPain Lab, Lyon Neuroscience Research Centre, CRNL - INSERM U 1028/CNRS UMR 5292, University of Lyon, Lyon, France; Hospices Civils de Lyon, Neurological Hospital, Department of Functional Neurology and Epileptology, Lyon F - 69003, France
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Lin C, Liu D, Liu Y, Chen Z, Wei X, Liu H, Wang K, Liu T, Xiao L, Rong L. Altered functional activity of the precuneus and superior temporal gyrus in patients with residual dizziness caused by benign paroxysmal positional vertigo. Front Neurosci 2023; 17:1221579. [PMID: 37901419 PMCID: PMC10600499 DOI: 10.3389/fnins.2023.1221579] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2023] [Accepted: 09/29/2023] [Indexed: 10/31/2023] Open
Abstract
Objective Benign paroxysmal positional vertigo (BPPV) is a common clinical vertigo disease, and the most effective treatment for this disease is canal repositioning procedures (CRP). Most patients return to normal after a single treatment. However, some patients still experience residual dizziness (RD) after treatment, and this disease's pathogenesis is currently unclear. The purpose of this study is to explore whether there are abnormal brain functional activities in patients with RD by using resting-state functional magnetic resonance imaging (rs-fMRI) and to provide imaging evidence for the study of the pathogenesis of RD. Materials and methods The BPPV patients in the Second Affiliated Hospital of Xuzhou Medical University had been included from December 2021 to November 2022. All patients had been received the collection of demographic and clinical characteristics (age, gender, involved semicircular canal, affected side, CRP times, BPPV course, duration of RD symptoms, and whether they had hypertension, diabetes, coronary heart disease.), scale assessment, including Dizziness Handicap Inventory (DHI), Hamilton Anxiety Inventory (HAMA), Hamilton Depression Inventory (HAMD), rs-fMRI data collection, CRP treatment, and then a one-month follow-up. According to the follow-up results, 18 patients with RD were included. At the same time, we selected 19 healthy individuals from our hospital's physical examination center who matched their age, gender as health controls (HC). First, the amplitude of low-frequency fluctuations (ALFF) analysis method was used to compare the local functional activities of the two groups of subjects. Then, the brain regions with different ALFF results were extracted as seed points. Functional connectivity (FC) analysis method based on seed points was used to explore the whole brain FC of patients with RD. Finally, a correlation analysis between clinical features and rs-fMRI data was performed. Results Compared to the HC, patients with RD showed lower ALFF value in the right precuneus and higher ALFF value in the right superior temporal gyrus (STG). When using the right STG as a seed point, it was found that the FC between the right STG, the right supramarginal gyrus (SMG), and the left precuneus was decreased in RD patients. However, no significant abnormalities in the FC were observed when using the right precuneus as a seed point. Conclusion In patients with RD, the local functional activity of the right precuneus is weakened, and the local functional activity of the right STG is enhanced. Furthermore, the FC between the right STG, the right SMG, and the left precuneus is weakened. These changes may explain the symptoms of dizziness, floating sensation, walking instability, neck tightness, and other symptoms in patients with RD to a certain extent.
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Affiliation(s)
- Cunxin Lin
- Department of Neurology, The Second Affiliated Hospital of Xuzhou Medical University, Xuzhou, Jiangsu, China
- Graduate School of Xuzhou Medical University, Xuzhou, Jiangsu, China
| | - Dan Liu
- Department of Neurology, The Second Affiliated Hospital of Xuzhou Medical University, Xuzhou, Jiangsu, China
- Graduate School of Xuzhou Medical University, Xuzhou, Jiangsu, China
| | - Yueji Liu
- Department of Neurology, The Second Affiliated Hospital of Xuzhou Medical University, Xuzhou, Jiangsu, China
- Graduate School of Xuzhou Medical University, Xuzhou, Jiangsu, China
| | - Zhengwei Chen
- Department of Neurology, The Second Affiliated Hospital of Xuzhou Medical University, Xuzhou, Jiangsu, China
| | - Xiue Wei
- Department of Neurology, The Second Affiliated Hospital of Xuzhou Medical University, Xuzhou, Jiangsu, China
| | - Haiyan Liu
- Department of Neurology, The Second Affiliated Hospital of Xuzhou Medical University, Xuzhou, Jiangsu, China
| | - Kai Wang
- Department of Neurology, The Second Affiliated Hospital of Xuzhou Medical University, Xuzhou, Jiangsu, China
| | - Tengfei Liu
- Department of Neurology, The Second Affiliated Hospital of Xuzhou Medical University, Xuzhou, Jiangsu, China
| | - Lijie Xiao
- Department of Neurology, The Second Affiliated Hospital of Xuzhou Medical University, Xuzhou, Jiangsu, China
| | - Liangqun Rong
- Department of Neurology, The Second Affiliated Hospital of Xuzhou Medical University, Xuzhou, Jiangsu, China
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Sulpizio V, Fattori P, Pitzalis S, Galletti C. Functional organization of the caudal part of the human superior parietal lobule. Neurosci Biobehav Rev 2023; 153:105357. [PMID: 37572972 DOI: 10.1016/j.neubiorev.2023.105357] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2023] [Revised: 07/31/2023] [Accepted: 08/09/2023] [Indexed: 08/14/2023]
Abstract
Like in macaque, the caudal portion of the human superior parietal lobule (SPL) plays a key role in a series of perceptive, visuomotor and somatosensory processes. Here, we review the functional properties of three separate portions of the caudal SPL, i.e., the posterior parieto-occipital sulcus (POs), the anterior POs, and the anterior part of the caudal SPL. We propose that the posterior POs is mainly dedicated to the analysis of visual motion cues useful for object motion detection during self-motion and for spatial navigation, while the more anterior parts are implicated in visuomotor control of limb actions. The anterior POs is mainly involved in using the spotlight of attention to guide reach-to-grasp hand movements, especially in dynamic environments. The anterior part of the caudal SPL plays a central role in visually guided locomotion, being implicated in controlling leg-related movements as well as the four limbs interaction with the environment, and in encoding egomotion-compatible optic flow. Together, these functions reveal how the caudal SPL is strongly implicated in skilled visually-guided behaviors.
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Affiliation(s)
- Valentina Sulpizio
- Department of Psychology, Sapienza University, Rome, Italy; Department of Cognitive and Motor Rehabilitation and Neuroimaging, Santa Lucia Foundation (IRCCS Fondazione Santa Lucia), Rome, Italy.
| | - Patrizia Fattori
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy
| | - Sabrina Pitzalis
- Department of Cognitive and Motor Rehabilitation and Neuroimaging, Santa Lucia Foundation (IRCCS Fondazione Santa Lucia), Rome, Italy; Department of Movement, Human and Health Sciences, University of Rome ''Foro Italico'', Rome, Italy
| | - Claudio Galletti
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy
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Lyu D, Stieger JR, Xin C, Ma E, Lusk Z, Aparicio MK, Werbaneth K, Perry CM, Deisseroth K, Buch V, Parvizi J. Causal evidence for the processing of bodily self in the anterior precuneus. Neuron 2023; 111:2502-2512.e4. [PMID: 37295420 DOI: 10.1016/j.neuron.2023.05.013] [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: 11/09/2022] [Revised: 03/05/2023] [Accepted: 05/14/2023] [Indexed: 06/12/2023]
Abstract
To probe the causal importance of the human posteromedial cortex (PMC) in processing the sense of self, we studied a rare cohort of nine patients with electrodes implanted bilaterally in the precuneus, posterior cingulate, and retrosplenial regions with a combination of neuroimaging, intracranial recordings, and direct cortical stimulations. In all participants, the stimulation of specific sites within the anterior precuneus (aPCu) caused dissociative changes in physical and spatial domains. Using single-pulse electrical stimulations and neuroimaging, we present effective and resting-state connectivity of aPCu hot zone with the rest of the brain and show that they are located outside the boundaries of the default mode network (DMN) but connected reciprocally with it. We propose that the function of this subregion of the PMC is integral to a range of cognitive processes that require the self's physical point of reference, given its location within a spatial environment.
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Affiliation(s)
- Dian Lyu
- Laboratory of Behavioral and Cognitive Neuroscience, Stanford University School of Medicine, Stanford, CA, USA; Human Intracranial Cognitive Electrophysiology Program, Stanford University School of Medicine, Stanford, CA, USA; Departments of Neurology and Neurological Sciences, Stanford University School of Medicine, Stanford, CA, USA.
| | - James Robert Stieger
- Laboratory of Behavioral and Cognitive Neuroscience, Stanford University School of Medicine, Stanford, CA, USA; Human Intracranial Cognitive Electrophysiology Program, Stanford University School of Medicine, Stanford, CA, USA; Departments of Neurology and Neurological Sciences, Stanford University School of Medicine, Stanford, CA, USA
| | - Cindy Xin
- Laboratory of Behavioral and Cognitive Neuroscience, Stanford University School of Medicine, Stanford, CA, USA; Human Intracranial Cognitive Electrophysiology Program, Stanford University School of Medicine, Stanford, CA, USA; Departments of Neurology and Neurological Sciences, Stanford University School of Medicine, Stanford, CA, USA
| | - Eileen Ma
- Laboratory of Behavioral and Cognitive Neuroscience, Stanford University School of Medicine, Stanford, CA, USA; Human Intracranial Cognitive Electrophysiology Program, Stanford University School of Medicine, Stanford, CA, USA; Departments of Neurology and Neurological Sciences, Stanford University School of Medicine, Stanford, CA, USA
| | - Zoe Lusk
- Laboratory of Behavioral and Cognitive Neuroscience, Stanford University School of Medicine, Stanford, CA, USA; Human Intracranial Cognitive Electrophysiology Program, Stanford University School of Medicine, Stanford, CA, USA; Departments of Neurology and Neurological Sciences, Stanford University School of Medicine, Stanford, CA, USA
| | - Mariel Kalkach Aparicio
- Laboratory of Behavioral and Cognitive Neuroscience, Stanford University School of Medicine, Stanford, CA, USA
| | - Katherine Werbaneth
- Laboratory of Behavioral and Cognitive Neuroscience, Stanford University School of Medicine, Stanford, CA, USA; Human Intracranial Cognitive Electrophysiology Program, Stanford University School of Medicine, Stanford, CA, USA; Departments of Neurology and Neurological Sciences, Stanford University School of Medicine, Stanford, CA, USA
| | - Claire Megan Perry
- Laboratory of Behavioral and Cognitive Neuroscience, Stanford University School of Medicine, Stanford, CA, USA; Human Intracranial Cognitive Electrophysiology Program, Stanford University School of Medicine, Stanford, CA, USA; Departments of Neurology and Neurological Sciences, Stanford University School of Medicine, Stanford, CA, USA
| | - Karl Deisseroth
- Departments of Psychiatry, Stanford University School of Medicine, Stanford, CA, USA; Howard Hughes Medical Institute, Stanford University School of Medicine, Stanford, CA, USA
| | - Vivek Buch
- Human Intracranial Cognitive Electrophysiology Program, Stanford University School of Medicine, Stanford, CA, USA; Departments of Neurosurgery, Stanford University School of Medicine, Stanford, CA, USA
| | - Josef Parvizi
- Laboratory of Behavioral and Cognitive Neuroscience, Stanford University School of Medicine, Stanford, CA, USA; Human Intracranial Cognitive Electrophysiology Program, Stanford University School of Medicine, Stanford, CA, USA; Departments of Neurology and Neurological Sciences, Stanford University School of Medicine, Stanford, CA, USA; Departments of Neurosurgery, Stanford University School of Medicine, Stanford, CA, USA.
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Togo M, Matsumoto R, Usami K, Kobayashi K, Takeyama H, Nakae T, Shimotake A, Kikuchi T, Yoshida K, Matsuhashi M, Kunieda T, Miyamoto S, Takahashi R, Ikeda A. Distinct connectivity patterns in human medial parietal cortices: Evidence from standardized connectivity map using cortico-cortical evoked potential. Neuroimage 2022; 263:119639. [PMID: 36155245 DOI: 10.1016/j.neuroimage.2022.119639] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2021] [Revised: 09/10/2022] [Accepted: 09/19/2022] [Indexed: 11/21/2022] Open
Abstract
The medial parietal cortices are components of the default mode network (DMN), which are active in the resting state. The medial parietal cortices include the precuneus and the dorsal posterior cingulate cortex (dPCC). Few studies have mentioned differences in the connectivity in the medial parietal cortices, and these differences have not yet been precisely elucidated. Electrophysiological connectivity is essential for understanding cortical function or functional differences. Since little is known about electrophysiological connections from the medial parietal cortices in humans, we evaluated distinct connectivity patterns in the medial parietal cortices by constructing a standardized connectivity map using cortico-cortical evoked potential (CCEP). This study included nine patients with partial epilepsy or a brain tumor who underwent chronic intracranial electrode placement covering the medial parietal cortices. Single-pulse electrical stimuli were delivered to the medial parietal cortices (38 pairs of electrodes). Responses were standardized using the z-score of the baseline activity, and a response density map was constructed in the Montreal Neurological Institutes (MNI) space. The precuneus tended to connect with the inferior parietal lobule (IPL), the occipital cortex, superior parietal lobule (SPL), and the dorsal premotor area (PMd) (the four most active regions, in descending order), while the dPCC tended to connect to the middle cingulate cortex, SPL, precuneus, and IPL. The connectivity pattern differs significantly between the precuneus and dPCC stimulation (p<0.05). Regarding each part of the medial parietal cortices, the distributions of parts of CCEP responses resembled those of the functional connectivity database. Based on how the dPCC was connected to the medial frontal area, SPL, and IPL, its connectivity pattern could not be explained by DMN alone, but suggested a mixture of DMN and the frontoparietal cognitive network. These findings improve our understanding of the connectivity profile within the medial parietal cortices. The electrophysiological connectivity is the basis of propagation of electrical activities in patients with epilepsy. In addition, it helps us to better understand the epileptic network arising from the medial parietal cortices.
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Affiliation(s)
- Masaya Togo
- Department of Neurology, Kyoto University Graduate School of Medicine, Japan; Division of Neurology, Kobe University Graduate School of Medicine, 7-5-2 Kusunoki-cho, Chuo-ku, Kobe, 650-0017, Japan
| | - Riki Matsumoto
- Department of Neurology, Kyoto University Graduate School of Medicine, Japan; Division of Neurology, Kobe University Graduate School of Medicine, 7-5-2 Kusunoki-cho, Chuo-ku, Kobe, 650-0017, Japan.
| | - Kiyohide Usami
- Department of Neurology, Kyoto University Graduate School of Medicine, Japan
| | - Katsuya Kobayashi
- Department of Neurology, Kyoto University Graduate School of Medicine, Japan
| | - Hirofumi Takeyama
- Department of Respiratory Care and Sleep Control Medicine, Kyoto University Graduate School of Medicine, Japan; Department of Neurology, Japanese Red Cross Otsu Hospital, Japan
| | - Takuro Nakae
- Department of Neurosurgery, Shiga General Hospital, Japan
| | - Akihiro Shimotake
- Department of Neurology, Kyoto University Graduate School of Medicine, Japan
| | - Takayuki Kikuchi
- Department of Neurosurgery, Kyoto University Graduate School of Medicine, Japan
| | - Kazumichi Yoshida
- Department of Neurosurgery, Kyoto University Graduate School of Medicine, Japan
| | - Masao Matsuhashi
- Departments of Epilepsy, Movement Disorders and Physiology, Kyoto University Graduate School of Medicine, 54 Kawahara-cho, Sakyo-ku, Kyoto, 606-8507, Japan
| | - Takeharu Kunieda
- Department of Neurosurgery, Ehime University Graduate School of Medicine, Japan
| | - Susumu Miyamoto
- Department of Neurosurgery, Kyoto University Graduate School of Medicine, Japan
| | - Ryosuke Takahashi
- Department of Neurology, Kyoto University Graduate School of Medicine, Japan
| | - Akio Ikeda
- Departments of Epilepsy, Movement Disorders and Physiology, Kyoto University Graduate School of Medicine, 54 Kawahara-cho, Sakyo-ku, Kyoto, 606-8507, Japan
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Fu W, Bai Y, He F, Wei D, Wang Y, Shi Y, An X, Han J, Wang X. The Association Between Precuneus Function and Residual Dizziness in Patients With Benign Paroxysmal Positional Vertigo. Front Neurol 2022; 13:828642. [PMID: 35493847 PMCID: PMC9039311 DOI: 10.3389/fneur.2022.828642] [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: 12/03/2021] [Accepted: 02/11/2022] [Indexed: 11/25/2022] Open
Abstract
Objectives The purpose of this study was to apply the amplitude of the low-frequency fluctuation (ALFF) method to investigate the spontaneous brain activity alterations in patients with residual dizziness (RD) after successful canalith repositioning manoeuvre for benign paroxysmal positional vertigo (BPPV). Methods All BPPV patients underwent visual vertigo analog scale (VVAS) evaluations and functional magnetic resonance imaging (fMRI). The ALFF method was used to assess the spontaneous brain activity. Screening of brain regions with significant changes in ALFF values was based on analysis of the whole brain. We further analyze the relationship between ALFF values of the altered regions and VVAS scores in BPPV patients with RD. Results Fifteen BPPV patients with RD and fifteen without RD were recruited in this study. In contrast to without RD, RD patients exhibited increased scores in VVAS tests (p < 0.001) and RD patients also showed significant ALFF decrease in the bilateral precuneus (left: 251 voxels; x = −10, y = −69, z = 51; peak t-value = −3.25; right: 170 voxels; x = 4, y = −59, z = 42; peak t-value = −3.43). Correlation analysis revealed that the mean ALFF z-values in the left precuneus displayed significant negative correlations with the VVAS scores(r = −0.44, p = 0.01). Conclusions This study shows that RD is associated with left precuneus function as revealed by fMRI. It might provide useful information for explaining neural mechanisms in BPPV patients with RD.
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Affiliation(s)
- Wei Fu
- Department of Geriatrics, Xijing Hospital, Fourth Military Medical University, Xi'an, China
| | - Ya Bai
- Department of Neurology, Xijing Hospital, Fourth Military Medical University, Xi'an, China
| | - Feng He
- Department of Neurology, Xijing Hospital, Fourth Military Medical University, Xi'an, China
| | - Dong Wei
- Department of Neurology, Xijing Hospital, Fourth Military Medical University, Xi'an, China
| | - Yuanyuan Wang
- Department of Neurology, Xijing Hospital, Fourth Military Medical University, Xi'an, China
| | - Ying Shi
- Department of Neurology, Xijing Hospital, Fourth Military Medical University, Xi'an, China
| | - Xinyue An
- Department of Neurology, Xijing Hospital, Fourth Military Medical University, Xi'an, China
| | - Junliang Han
- Department of Neurology, Xijing Hospital, Fourth Military Medical University, Xi'an, China
- *Correspondence: Junliang Han
| | - Xiaoming Wang
- Department of Geriatrics, Xijing Hospital, Fourth Military Medical University, Xi'an, China
- Xiaoming Wang
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12
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Turek G, Skjei K. Seizure semiology, localization, and the 2017 ILAE seizure classification. Epilepsy Behav 2022; 126:108455. [PMID: 34894624 DOI: 10.1016/j.yebeh.2021.108455] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Revised: 11/13/2021] [Accepted: 11/16/2021] [Indexed: 11/26/2022]
Abstract
In the study of epilepsy, the term semiology is used to comprise the clinical characteristics of a seizure, both subjective symptoms and objective phenomena. It is produced by activation of the symptomagenic zone, and an accurate and comprehensive understanding of the localizing value of seizure semiology is crucial for presurgical evaluation and planning. Myriad publications in epilepsy journals detail correlations between various semiological features and activation of specific cortical regions. Traditionally these studies involved scalp EEG recorded in epilepsy monitoring units. The increasing use of invasive monitoring, and specifically the use of depth electrodes and stereo-electroencephalography, has advanced our understanding of the characteristics of seizures arising from ictal foci deep to the scalp, including the cingulate, insula and operculum. However, the distinction between seizure onset and symptomogenic zones is not always clear. In 2017 the International League Against Epilepsy (ILAE) published an operational classification of seizure types based heavily on seizure semiology. The current paper provides an updated review of the current body of knowledge relating to seizure semiology, incorporating both scalp EEG studies and more recent stereo-electroencephalography discoveries in the framework of the 2017 ILAE classification.
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Affiliation(s)
- Grant Turek
- Department of Neurology, University of Louisville, 401 E. Chestnut St. Unit 510, Louisville, KY 40202-5710, United States.
| | - Karen Skjei
- Department of Neurology, University of Texas at Austin, Dell Medical School, 1601 Trinity St., Bldg B, Strop Z0700, Austin, TX 78712, United States
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Kabel AEMH, Afifi KH, ElFakhrany SM, Moaty AS. Cervical and ocular vestibular evoked myogenic potentials in epileptic patients. THE EGYPTIAN JOURNAL OF OTOLARYNGOLOGY 2021; 37:51. [DOI: 10.1186/s43163-021-00114-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Accepted: 05/06/2021] [Indexed: 09/02/2023]
Abstract
Abstract
Background
Vertigo and dizziness are very common complaints that may be related to epilepsy. The purpose of this study was to assess vestibulo-spinal and linear vestibulo-ocular function in epileptic patients in the inter ictal period. The current observational study was carried out in audio-vestibular unit Menoufia University. Subjects in the current study were divided into two groups: The control group included 30 normal individuals not complaining from any dizzy symptoms and the epileptic cases group included 30 epileptic patients. All subjects in the study were submitted to cervical and ocular vestibular evoked myogenic potential.
Results
There was no significant difference between the control and epileptic group regarding the age and sex distribution. Sixty-seven percent of epileptic cases had dizzy symptoms. There was statistically significant difference in the latency and amplitude of c and o VEMP between the control and the epileptic group, 39/60 ears (65%) in the study group had cVEMP abnormalities, 32/60 ears (53%) had oVEMP abnormalities. Abnormal c and o VEMP were reported in 28/60 ears (46.7%). There was statistically significant relationship between VEMP abnormalities and duration of seizures, frequency of epileptic attacks, and type of therapy.
Conclusion
Vestibular abnormalities were frequently reported in epileptic patients in the current study which may be related to the severity and control of epilepsy.
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Dionisio S, Mayoglou L, Cho SM, Prime D, Flanigan PM, Lega B, Mosher J, Leahy R, Gonzalez-Martinez J, Nair D. Connectivity of the human insula: A cortico-cortical evoked potential (CCEP) study. Cortex 2019; 120:419-442. [PMID: 31442863 DOI: 10.1016/j.cortex.2019.05.019] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2019] [Revised: 05/02/2019] [Accepted: 05/22/2019] [Indexed: 11/24/2022]
Abstract
OBJECTIVE The human insula is increasingly being implicated as a multimodal functional network hub involved in a large variety of complex functions. Due to its inconspicuous location and highly vascular anatomy, it has historically been difficult to study. Cortico-cortical evoked potentials (CCEPs), utilize low frequency stimulation to map cerebral networks. They were used to study connections of the human insula. METHODS CCEP data was acquired from each sub-region of the dominant and non-dominant insula in 30 patients who underwent stereo-EEG. Connectivity strength to the various cortical regions was obtained via a measure of root mean square (RMS), calculated from each gyrus of the insula and ranked into weighted means. RESULTS The results of all cumulative CCEP responses for each individual gyrus were represented by circro plots. Forty-nine individual CCEP pairs were stimulated across all the gyri from the right and left insula. In brief, the left insula contributed more greatly to language areas. Sensory function, pain, saliency processing and vestibular function were more heavily implicated from the right insula. Connections to the primary auditory cortex arose from both insula regions. Both posterior insula regions showed significant contralateral connectivity. Ipsilateral mesial temporal connections were seen from both insula regions. In visual function, we further report the novel finding of a direct connection between the right posterior insula and left visual cortex. SIGNIFICANCE The insula is a major multi-modal network hub with the cerebral cortex having major roles in language, sensation, auditory, visual, limbic and vestibular functions as well as saliency processing. In temporal lobe epilepsy surgery failure, the insula may be implicated as an extra temporal cause, due to the strong mesial temporal connectivity findings.
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Affiliation(s)
- Sasha Dionisio
- Epilepsy Center, Cleveland Clinic, Neurological Institute, Cleveland, OH, USA; Epilepsy Centre, Mater Centre for Neurosciences, Brisbane, Australia.
| | - Lazarus Mayoglou
- Epilepsy Center, Cleveland Clinic, Neurological Institute, Cleveland, OH, USA; Epilepsy Center, UPMC Hamot, Erie, PA, USA
| | - Sung-Min Cho
- Epilepsy Center, Cleveland Clinic, Neurological Institute, Cleveland, OH, USA
| | - David Prime
- Epilepsy Centre, Mater Centre for Neurosciences, Brisbane, Australia; Griffith School of Electrical Engineering, Nathan Campus, QLD, Australia
| | - Patrick M Flanigan
- Epilepsy Center, Cleveland Clinic, Neurological Institute, Cleveland, OH, USA
| | - Bradley Lega
- Epilepsy Center, Cleveland Clinic, Neurological Institute, Cleveland, OH, USA; Neurological Surgery, University of Texas-Southwestern, Dallas, TX, USA
| | - John Mosher
- Epilepsy Center, Cleveland Clinic, Neurological Institute, Cleveland, OH, USA
| | - Richard Leahy
- Signal and Image Processing Institute, University of Southern California, Los Angeles, CA, USA
| | | | - Dileep Nair
- Epilepsy Center, Cleveland Clinic, Neurological Institute, Cleveland, OH, USA
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15
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Repetitive transcranial magnetic stimulation reveals a causal role of the human precuneus in spatial updating. Sci Rep 2018; 8:10171. [PMID: 29977007 PMCID: PMC6033850 DOI: 10.1038/s41598-018-28487-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2018] [Accepted: 06/08/2018] [Indexed: 11/10/2022] Open
Abstract
As we move through an environment, the positions of surrounding objects relative to our body constantly change, with some objects even leaving our field of view. As a consequence, maintaining orientation requires spatial updating, the continuous monitoring of self-motion cues to update external locations within an egocentric frame of reference. While previous research using functional magnetic resonance imaging has implicated the precuneus in spatial updating, direct evidence for this claim is missing. To address this important question, we applied theta burst repetitive transcranial magnetic stimulation (rTMS) over the precuneus to induce a “virtual lesion”. Following stimulation, participants were tested in a large-scale virtual environment in which they had to use visual self-motion information to keep track of the position of virtual objects. Compared to sham stimulation, rTMS affected working memory traces for object locations. Critically, rTMS further impaired the ability to update these locations whenever participants experienced simulated movement. As this effect could not be explained by working memory deficits alone, we conclude that visual spatial updating relies on the construction of updated representations of egocentric object locations within the precuneus. Together, these findings establish the precuneus as performing key computations for the formation of cognitive maps.
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16
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Fox KCR, Andrews-Hanna JR, Mills C, Dixon ML, Markovic J, Thompson E, Christoff K. Affective neuroscience of self-generated thought. Ann N Y Acad Sci 2018; 1426:25-51. [PMID: 29754412 DOI: 10.1111/nyas.13740] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2017] [Revised: 03/16/2018] [Accepted: 03/28/2018] [Indexed: 01/05/2023]
Abstract
Despite increasing scientific interest in self-generated thought-mental content largely independent of the immediate environment-there has yet to be any comprehensive synthesis of the subjective experience and neural correlates of affect in these forms of thinking. Here, we aim to develop an integrated affective neuroscience encompassing many forms of self-generated thought-normal and pathological, moderate and excessive, in waking and in sleep. In synthesizing existing literature on this topic, we reveal consistent findings pertaining to the prevalence, valence, and variability of emotion in self-generated thought, and highlight how these factors might interact with self-generated thought to influence general well-being. We integrate these psychological findings with recent neuroimaging research, bringing attention to the neural correlates of affect in self-generated thought. We show that affect in self-generated thought is prevalent, positively biased, highly variable (both within and across individuals), and consistently recruits many brain areas implicated in emotional processing, including the orbitofrontal cortex, amygdala, insula, and medial prefrontal cortex. Many factors modulate these typical psychological and neural patterns, however; the emerging affective neuroscience of self-generated thought must endeavor to link brain function and subjective experience in both everyday self-generated thought as well as its dysfunctions in mental illness.
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Affiliation(s)
- Kieran C R Fox
- Department of Neurology and Neurological Sciences, Stanford University, Stanford, California
- Department of Psychology, University of British Columbia, Vancouver, British Columbia, Canada
| | - Jessica R Andrews-Hanna
- Department of Psychology and Interdisciplinary Program in Cognitive Science, University of Arizona, Tucson, Arizona
| | - Caitlin Mills
- Department of Psychology, University of British Columbia, Vancouver, British Columbia, Canada
| | - Matthew L Dixon
- Department of Psychology, University of British Columbia, Vancouver, British Columbia, Canada
- Department of Psychology, University of Toronto, Toronto, Ontario, Canada
| | - Jelena Markovic
- Department of Philosophy, University of British Columbia, Vancouver, British Columbia, Canada
| | - Evan Thompson
- Department of Philosophy, University of British Columbia, Vancouver, British Columbia, Canada
| | - Kalina Christoff
- Department of Psychology, University of British Columbia, Vancouver, British Columbia, Canada
- Centre for Brain Health, University of British Columbia, Vancouver, British Columbia, Canada
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17
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Uesaki M, Takemura H, Ashida H. Computational neuroanatomy of human stratum proprium of interparietal sulcus. Brain Struct Funct 2018; 223:489-507. [PMID: 28871500 PMCID: PMC5772143 DOI: 10.1007/s00429-017-1492-1] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2017] [Accepted: 08/04/2017] [Indexed: 11/19/2022]
Abstract
Recent advances in diffusion-weighted MRI (dMRI) and tractography have enabled identification of major long-range white matter tracts in the human brain. Yet, our understanding of shorter tracts, such as those within the parietal lobe, remains limited. Over a century ago, a tract connecting the superior and inferior parts of the parietal cortex was identified in a post-mortem study: stratum proprium of interparietal sulcus (SIPS; Sachs, Das hemisphärenmark des menschlichen grosshirns. Verlag von georg thieme, Leipzig, 1892). The tract has since been replicated in another fibre dissection study (Vergani et al., Cortex 56:145-156, 2014), however, it has not been fully investigated in the living human brain and its precise anatomical properties are yet to be described. We used dMRI and tractography to identify and characterise SIPS in vivo, and explored its spatial proximity to the cortical areas associated with optic-flow processing using fMRI. SIPS was identified bilaterally in all subjects, and its anatomical position and trajectory are consistent with previous post-mortem studies. Subsequent evaluation of the tractography results using the linear fascicle evaluation and virtual lesion analysis yielded strong statistical evidence for SIPS. We also found that the SIPS endpoints are adjacent to the optic-flow selective areas. In sum, we show that SIPS is a short-range tract connecting the superior and inferior parts of the parietal cortex, wrapping around the intraparietal sulcus, and that it may be a crucial anatomy underlying optic-flow processing. In vivo identification and characterisation of SIPS will facilitate further research on SIPS in relation to cortical functions, their development, and diseases that affect them.
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Affiliation(s)
- Maiko Uesaki
- Department of Psychology, Graduate School of Letters, Kyoto University, Kyoto, Japan.
- Japan Society for the Promotion of Science, Tokyo, Japan.
- Open Innovation and Collaboration Research Organization, Ritsumeikan University, Osaka, Japan.
| | - Hiromasa Takemura
- Japan Society for the Promotion of Science, Tokyo, Japan.
- Center for Information and Neural Networks (CiNet), National Institute of Information and Communications Technology, and Osaka University, Suita, Japan.
- Graduate School of Frontier Biosciences, Osaka University, Suita, Japan.
| | - Hiroshi Ashida
- Department of Psychology, Graduate School of Letters, Kyoto University, Kyoto, Japan
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18
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Harroud A, Boucher O, Tran TPY, Harris L, Hall J, Dubeau F, Mohamed I, Bouthillier A, Nguyen DK. Precuneal epilepsy: Clinical features and surgical outcome. Epilepsy Behav 2017. [PMID: 28623753 DOI: 10.1016/j.yebeh.2017.05.018] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE The precuneus is a complex and highly connected structure located in the medial portion of the superior parietal lobule. The clinical presentation of precuneal epilepsy is poorly characterized, mostly because these patients have seldom been distinguished from those with other types of parietal lobe epilepsy. The present study aims to improve the understanding of precuneal epilepsy by detailing its clinical features and surgical outcomes. METHODS Six previously unreported cases of drug-resistant precuneal epilepsy investigated between 2002 and 2014 were retrospectively studied. Seizure focus was confirmed by presence of a lesion, intracranial monitoring, or post-operative seizure control when applicable. RESULTS Seizures arising from the precuneus have heterogeneous presentations, including body movement sensation, visual auras, eye movements, vestibular manifestations, and complex motor behaviors. Two patients with an anterior precuneus lesion described body movement sensations whereas two others with a posterior precuneus lesion experienced visual symptoms. Two of the five patients who underwent epilepsy surgery achieved good seizure control (Engel IA). One patient underwent gamma knife surgery with an Engel IV outcome. Surgical complications included contralateral visual field impairment, limb hypoesthesia and hemispatial neglect. One patient developed late-onset epilepsia partialis continua from a Rolandic subdural grid-related contusion. SIGNIFICANCE In absence of a clear precuneal epileptogenic lesion, recognition of a precuneal focus is challenging. Magnetoencephalography may sometimes localize the generator but invasive EEG remains in well-selected cases necessary to identify the seizure focus. Surgical failures may be explained by the widespread connectivity of the precuneus with distant and adjacent structures. Different ictal manifestations of precuneal epilepsy in this series provide a clinical correlate to the described functional subdivisions of the precuneus.
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Affiliation(s)
- Adil Harroud
- Montreal Neurological Institute and Hospital, McGill University, Montreal, Québec, Canada
| | - Olivier Boucher
- Departement of Psychology, Université de Montréal, Montreal, Canada
| | - Thi Phuoc Yen Tran
- Department of Internal Medicine, Hue University of Medicine and Pharmacy, Hue, Vietnam
| | - Louis Harris
- Division of Neurology, CHUM Notre-Dame, Université de Montréal, Montreal, Canada
| | - Jeffery Hall
- Montreal Neurological Institute and Hospital, McGill University, Montreal, Québec, Canada
| | - François Dubeau
- Montreal Neurological Institute and Hospital, McGill University, Montreal, Québec, Canada
| | - Ismail Mohamed
- Division of Pediatric Neurology, UAB School of Medicine, AL, United States
| | - Alain Bouthillier
- Division of Neurosurgery, CHUM Notre-Dame, Université de Montréal, Montreal, Canada
| | - Dang Khoa Nguyen
- Division of Neurology, CHUM Notre-Dame, Université de Montréal, Montreal, Canada.
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Cakmak YO, Ekinci G, Heinecke A, Çavdar S. A Possible Role of Prolonged Whirling Episodes on Structural Plasticity of the Cortical Networks and Altered Vertigo Perception: The Cortex of Sufi Whirling Dervishes. Front Hum Neurosci 2017; 11:3. [PMID: 28167905 PMCID: PMC5253366 DOI: 10.3389/fnhum.2017.00003] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2016] [Accepted: 01/03/2017] [Indexed: 12/14/2022] Open
Abstract
Although minutes of a spinning episode may induce vertigo in the healthy human, as a result of a possible perceptional plasticity, Sufi Whirling Dervishes (SWDs) can spin continuously for an hour without a vertigo perception.This unique long term vestibular system stimulation presents a potential human model to clarify the cortical networks underlying the resistance against vertigo. This study, therefore, aimed to investigate the potential structural cortical plasticity in SWDs. Magnetic resonance imaging (MRI) of 10 SWDs and 10 controls were obtained, using a 3T scanner. Cortical thickness in the whole cortex was calculated. Results demonstrated significantly thinner cortical areas for SWD subjects compared with the control group in the hubs of the default mode network (DMN), as well as in the motion perception and discrimination areas including the right dorsolateral prefrontal cortex (DLPFC), the right lingual gyrus and the left visual area 5 (V5)/middle temporal (MT) and the left fusiform gyrus. In conclusion, this is the first report that warrants the potential relationship of the motion/body perception related cortical networks and the prolonged term of whirling ability without vertigo or dizziness.
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Affiliation(s)
- Yusuf O Cakmak
- Department of Anatomy, School of Biomedical Sciences, University of Otago Dunedin, New Zealand
| | - Gazanfer Ekinci
- Radiology Department, School of Medicine, Marmara University Istanbul, Turkey
| | - Armin Heinecke
- Brain Innovation BV, Biopartner Center Maastricht, Netherlands
| | - Safiye Çavdar
- Department of Anatomy, School of Medicine, Koc University Istanbul, Turkey
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20
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Theys T, Minotti L, Tassi L, Lo Russo G, Benabid AL, Kahane P, Chabardès S. Mesial Extratemporal Lobe Epilepsy: Clinical Features and Surgical Strategies. Neurosurgery 2017; 80:269-278. [DOI: 10.1227/neu.0000000000001230] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2015] [Accepted: 12/17/2015] [Indexed: 11/19/2022] Open
Abstract
AbstractBACKGROUND: Extratemporal lobe epilepsy surgery remains a diagnostic and therapeutic challenge. Scalp electroencephalography (EEG) correlates, clinical semiology, and imaging findings are often ambiguous or difficult to interpret, necessitating the need for invasive recordings. This is particularly true for those extratemporal lobe epilepsy cases in which seizures develop from the midline.OBJECTIVE: The aim of this study was to examine the clinical features and surgical strategies in mesial extratemporal lobe epilepsy.METHODS: A retrospective study reviewing clinical and surgical characteristics was conducted in 30 patients who underwent epilepsy surgery in mesial extratemporal areas at our institution between 1991 and 2011.RESULTS: Although the location of the epileptogenic zone was associated with specific seizure types, semiology proved to be heterogeneous. Although scalp EEG was of good lateralizing value, it was poor for localizing the epileptogenic zone, necessitating a frequent need for invasive electroencephalographic recordings.CONCLUSION: Surgical resections in mesial extratemporal regions were found to be safe and resulted in satisfactory seizure outcomes.
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Affiliation(s)
- Tom Theys
- Department of Neurosurgery, Univer-sity Hospitals Leuven, Leuven, Belgium
| | - Lorella Minotti
- INSERM U836, Grenoble Institut des Neurosciences, Grenoble, France
| | - Laura Tassi
- Epilepsy Surgery Center, “Claudio Munari” Niguarda Hospital, Milan, Italy
| | - Giorgio Lo Russo
- Epilepsy Surgery Center, “Claudio Munari” Niguarda Hospital, Milan, Italy
| | | | - Philippe Kahane
- INSERM U836, Grenoble Institut des Neurosciences, Grenoble, France
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Abstract
In macaque, it has long been known since the late nineties that the medial parieto-occipital sulcus (POS) contains two regions, V6 and V6A, important for visual motion and action. While V6 is a retinotopically organized extrastriate area, V6A is a broadly retinotopically organized visuomotor area constituted by a ventral and dorsal subdivision (V6Av and V6Ad), both containing arm movement-related cells active during spatially directed reaching movements. In humans, these areas have been mapped only in recent years thanks to neuroimaging methods. In a series of brain mapping studies, by using a combination of functional magnetic resonance imaging methods such as wide-field retinotopy and task-evoked activity, we mapped human areas V6 (Pitzalis et al., 2006) and V6Av (Pitzalis et al., 2013 d) retinotopically and defined human V6Ad functionally as a pointing-selective region situated anteriorly in the close proximity of V6Av (Tosoni et al., 2014). Like in macaque, human V6 is a motion area (e.g., Pitzalis et al., 2010, 2012, 2013 a, b , c ), while V6Av and V6Ad respond to pointing movements (Tosoni et al., 2014). The retinotopic organization (when present), anatomical position, neighbor relations, and functional properties of these three areas closely resemble those reported for macaque V6 (Galletti et al., 1996, 1999 a), V6Av, and V6Ad (Galletti et al., 1999 b; Gamberini et al., 2011). We suggest that information on objects in depth which are translating in space, because of the self-motion, is processed in V6 and conveyed to V6A for evaluating object distance in a dynamic condition such as that created by self-motion, so to orchestrate the eye and arm movements necessary to reach or avoid static and moving objects in the environment.
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In the presence of others: Self-location, balance control and vestibular processing. Neurophysiol Clin 2015; 45:241-54. [DOI: 10.1016/j.neucli.2015.09.001] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2015] [Revised: 09/10/2015] [Accepted: 09/11/2015] [Indexed: 11/23/2022] Open
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Cha YH, Chakrapani S. Voxel Based Morphometry Alterations in Mal de Debarquement Syndrome. PLoS One 2015; 10:e0135021. [PMID: 26252893 PMCID: PMC4529307 DOI: 10.1371/journal.pone.0135021] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2015] [Accepted: 07/16/2015] [Indexed: 11/18/2022] Open
Abstract
Background Mal de debarquement syndrome (MdDS) is a disorder of chronic self-motion perception that occurs though entrainment to rhythmic background motion, such as from sea voyage, and involves the perception of low-frequency rocking that can last for months or years. The neural basis of this persistent sensory perception abnormality is not well understood. Methods We investigated grey matter volume differences underlying persistent MdDS by performing voxel-based morphometry on whole brain and pre-specified ROIs in 28 individuals with MdDS and comparing them to 18 age, sex, and handedness matched controls. Results MdDS participants exhibited greater grey matter volume in the left inferior parietal lobule, right inferior occipital gyrus (area V3v), right temporal pole, bilateral cerebellar hemispheric lobules VIII/IX and left lobule VIIa/VIIb. Grey matter volumes were lower in bilateral inferior frontal, orbitofrontal, pregenual anterior cingulate cortex (pgACC) and left superior medial gyri (t = 3.0, p<0.005uncorr). In ROI analyses, there were no volume differences in the middle occipital gyrus (region of V5/MT) or parietal operculum 2 (region of the parietoinsular vestibular cortex). Illness duration was positively related to grey matter volume in bilateral inferior frontal gyrus/anterior insula (IFG/AI), right posterior insula, superior parietal lobule, left middle occipital gyrus (V5/MT), bilateral postcentral gyrus, anterior cerebellum, and left cerebellar hemisphere and vermian lobule IX. In contrast, illness duration was negatively related to volume in pgACC, posterior middle cingulate gyrus (MCC), left middle frontal gyrus (dorsolateral prefrontal cortex-DLPFC), and right cerebellar hemispheric lobule VIIIb (t = 3.0, p<0.005uncorr). The most significant differences were decreased volume in the pgACC and increased volume in the left IFG/AI with longer illness duration (qFDRcorr <0.05). Concurrent medication use did not correlate with these findings or have a relationship with duration of illness. MdDS participants showed positive correlations between grey matter volume in pgACC and bilateral cerebellar lobules VIII/IX, which was not seen in controls. Conclusions Individuals with MdDS show brain volume differences from healthy controls as well as duration of illness dependent volume changes in (a) visual-vestibular processing areas (IPL, SPL, V3, V5/MT), (b) default mode network structures (cerebellar IX, IPL, ACC), (c) salience network structures (ACC and IFG/AI) (d) somatosensory network structures (postcentral gyrus, MCC, anterior cerebellum, cerebellar lobule VIII), and (e) a structure within the central executive network (DLPFC). The identification of these associations may enhance future investigations into how exposure to oscillating environments can modulate brain function and affect motion perception as well cognitive and affective control.
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Affiliation(s)
- Yoon-Hee Cha
- Laureate Institute for Brain Research, Tulsa, Oklahoma, United States of America
- University of California Los Angeles, Los Angeles, California, United States of America
- * E-mail:
| | - Shruthi Chakrapani
- University of California Los Angeles, Los Angeles, California, United States of America
- Semel Institute for Neuroscience and Human Behavior, Los Angeles, California, United States of America
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Balestrini S, Francione S, Mai R, Castana L, Casaceli G, Marino D, Provinciali L, Cardinale F, Tassi L. Multimodal responses induced by cortical stimulation of the parietal lobe: a stereo-electroencephalography study. Brain 2015; 138:2596-607. [DOI: 10.1093/brain/awv187] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2014] [Accepted: 05/05/2015] [Indexed: 12/30/2022] Open
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Tarnutzer AA, Lee SH, Robinson KA, Kaplan PW, Newman-Toker DE. Clinical and electrographic findings in epileptic vertigo and dizziness: a systematic review. Neurology 2015; 84:1595-604. [PMID: 25795644 DOI: 10.1212/wnl.0000000000001474] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2014] [Accepted: 12/22/2014] [Indexed: 11/15/2022] Open
Abstract
OBJECTIVE Seizures can cause vestibular symptoms, even without obvious epileptic features. We sought to characterize epileptic vertigo or dizziness (EVD) to improve differentiation from nonepileptic causes, particularly when vestibular symptoms are the sole manifestation. METHODS We conducted a systematic review with electronic (Medline) and manual search for English-language studies (1955-2014). Two independent reviewers selected studies. Study/patient characteristics were abstracted. We defined 3 study population types: (1) seizures, some experiencing vertigo/dizziness (disease cohort); (2) vertigo/dizziness, some due to seizures (symptom cohort); (3) vertigo/dizziness due to seizures in all patients (EVD-only cohort). RESULTS We identified 84 studies describing 11,354 patients (disease cohort = 8,129; symptom cohort = 2,965; EVD-only cohort = 260). Among 1,055 EVD patients in whom a distinction could be made, non-isolated EVD was present in 8.5%, isolated EVD in 0.8%. Thorough diagnostic workups (ictal EEG, vestibular testing, and brain MRI to exclude other causes) were rare (<0.1%). Ictal EEG was reported in 487 (4.3%), formal neuro-otologic assessment in 1,107 (9.7%). Localized EEG abnormalities (n = 350) were most frequently temporal (79.8%) and uncommonly parietal (11.8%). Duration of episodic vestibular symptoms varied, but was very brief (<30 seconds) in 69.6% of isolated EVD and 6.9% of non-isolated EVD. CONCLUSIONS Non-isolated EVD is much more prevalent than isolated EVD, which appears to be rare. Diagnostic evaluations for EVD are often incomplete. EVD is primarily associated with temporal lobe seizures; whether this reflects greater epidemiologic prevalence of temporal lobe seizures or a tighter association with dizziness/vertigo presentations than with other brain regions remains unknown. Consistent with clinical wisdom, isolated EVD spells often last just seconds, although many patients experience longer spells.
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Affiliation(s)
- Alexander A Tarnutzer
- From the Department of Neurology (A.A.T.), University Hospital Zurich and the University of Zurich, Switzerland; the Department of Neurology (S.-H.L.), Chonnam National University Medical School, Gwangju, South Korea; the Departments of Medicine (K.A.R.), Neurology (D.E.N.-T.), and Otolaryngology Head & Neck Surgery (D.E.N.-T.), The Johns Hopkins University School of Medicine; and the Department of Neurology (P.W.K.), Johns Hopkins Bayview Medical Center, Baltimore, MD.
| | - Seung-Han Lee
- From the Department of Neurology (A.A.T.), University Hospital Zurich and the University of Zurich, Switzerland; the Department of Neurology (S.-H.L.), Chonnam National University Medical School, Gwangju, South Korea; the Departments of Medicine (K.A.R.), Neurology (D.E.N.-T.), and Otolaryngology Head & Neck Surgery (D.E.N.-T.), The Johns Hopkins University School of Medicine; and the Department of Neurology (P.W.K.), Johns Hopkins Bayview Medical Center, Baltimore, MD
| | - Karen A Robinson
- From the Department of Neurology (A.A.T.), University Hospital Zurich and the University of Zurich, Switzerland; the Department of Neurology (S.-H.L.), Chonnam National University Medical School, Gwangju, South Korea; the Departments of Medicine (K.A.R.), Neurology (D.E.N.-T.), and Otolaryngology Head & Neck Surgery (D.E.N.-T.), The Johns Hopkins University School of Medicine; and the Department of Neurology (P.W.K.), Johns Hopkins Bayview Medical Center, Baltimore, MD
| | - Peter W Kaplan
- From the Department of Neurology (A.A.T.), University Hospital Zurich and the University of Zurich, Switzerland; the Department of Neurology (S.-H.L.), Chonnam National University Medical School, Gwangju, South Korea; the Departments of Medicine (K.A.R.), Neurology (D.E.N.-T.), and Otolaryngology Head & Neck Surgery (D.E.N.-T.), The Johns Hopkins University School of Medicine; and the Department of Neurology (P.W.K.), Johns Hopkins Bayview Medical Center, Baltimore, MD
| | - David E Newman-Toker
- From the Department of Neurology (A.A.T.), University Hospital Zurich and the University of Zurich, Switzerland; the Department of Neurology (S.-H.L.), Chonnam National University Medical School, Gwangju, South Korea; the Departments of Medicine (K.A.R.), Neurology (D.E.N.-T.), and Otolaryngology Head & Neck Surgery (D.E.N.-T.), The Johns Hopkins University School of Medicine; and the Department of Neurology (P.W.K.), Johns Hopkins Bayview Medical Center, Baltimore, MD
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Illusory self-motion perception evoked by caloric vestibular stimulation in sitting versus supine body positions. Behav Brain Res 2014; 272:150-5. [DOI: 10.1016/j.bbr.2014.06.051] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2014] [Revised: 06/23/2014] [Accepted: 06/24/2014] [Indexed: 10/25/2022]
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Mazzola L, Lopez C, Faillenot I, Chouchou F, Mauguière F, Isnard J. Vestibular responses to direct stimulation of the human insular cortex. Ann Neurol 2014; 76:609-19. [DOI: 10.1002/ana.24252] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2013] [Revised: 08/08/2014] [Accepted: 08/11/2014] [Indexed: 11/06/2022]
Affiliation(s)
- Laure Mazzola
- Neurology Department; University Hospital; St-Etienne
- Team “Central Integration of Pain”; Lyon Neuroscience Research Center, National Institute of Health and Medical Research Unit 1028, National Center for Scientific Research Mixed Unit of Research 5292; Lyon
- Jean Monnet University; St-Etienne
| | - Christophe Lopez
- Aix Marseille University, National Center for Scientific Research, Integrative and Adaptative Neurosciences Mixed Unit of Research 7260; Marseille
| | - Isabelle Faillenot
- Neurology Department; University Hospital; St-Etienne
- Team “Central Integration of Pain”; Lyon Neuroscience Research Center, National Institute of Health and Medical Research Unit 1028, National Center for Scientific Research Mixed Unit of Research 5292; Lyon
- Jean Monnet University; St-Etienne
| | - Florian Chouchou
- Team “Central Integration of Pain”; Lyon Neuroscience Research Center, National Institute of Health and Medical Research Unit 1028, National Center for Scientific Research Mixed Unit of Research 5292; Lyon
| | - François Mauguière
- Team “Central Integration of Pain”; Lyon Neuroscience Research Center, National Institute of Health and Medical Research Unit 1028, National Center for Scientific Research Mixed Unit of Research 5292; Lyon
- Functional Neurology and Epilepsy Department; Neurological Hospital, Civil Hospices of Lyon; Lyon
- Claude Bernard University; Lyon France
| | - Jean Isnard
- Team “Central Integration of Pain”; Lyon Neuroscience Research Center, National Institute of Health and Medical Research Unit 1028, National Center for Scientific Research Mixed Unit of Research 5292; Lyon
- Functional Neurology and Epilepsy Department; Neurological Hospital, Civil Hospices of Lyon; Lyon
- Claude Bernard University; Lyon France
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Falconer CJ, Mast FW. Balancing the mind: vestibular induced facilitation of egocentric mental transformations. Exp Psychol 2014; 59:332-9. [PMID: 22750744 DOI: 10.1027/1618-3169/a000161] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The body schema is a key component in accomplishing egocentric mental transformations, which rely on bodily reference frames. These reference frames are based on a plurality of different cognitive and sensory cues among which the vestibular system plays a prominent role. We investigated whether a bottom-up influence of vestibular stimulation modulates the ability to perform egocentric mental transformations. Participants were significantly faster to make correct spatial judgments during vestibular stimulation as compared to sham stimulation. Interestingly, no such effects were found for mental transformation of hand stimuli or during mental transformations of letters, thus showing a selective influence of vestibular stimulation on the rotation of whole-body reference frames. Furthermore, we found an interaction with the angle of rotation and vestibular stimulation demonstrating an increase in facilitation during mental body rotations in a direction congruent with rightward vestibular afferents. We propose that facilitation reflects a convergence in shared brain areas that process bottom-up vestibular signals and top-down imagined whole-body rotations, including the precuneus and tempero-parietal junction. Ultimately, our results show that vestibular information can influence higher-order cognitive processes, such as the body schema and mental imagery.
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Berkovich-Ohana A, Dor-Ziderman Y, Glicksohn J, Goldstein A. Alterations in the sense of time, space, and body in the mindfulness-trained brain: a neurophenomenologically-guided MEG study. Front Psychol 2013; 4:912. [PMID: 24348455 PMCID: PMC3847819 DOI: 10.3389/fpsyg.2013.00912] [Citation(s) in RCA: 77] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2013] [Accepted: 11/16/2013] [Indexed: 12/20/2022] Open
Abstract
Meditation practice can lead to what have been referred to as “altered states of consciousness.”One of the phenomenological characteristics of these states is a joint alteration in the sense of time, space, and body. Here, we set out to study the unique experiences of alteration in the sense of time and space by collaborating with a select group of 12 long-term mindfulness meditation (MM) practitioners in a neurophenomenological setup, utilizing first-person data to guide the neural analyses. We hypothesized that the underlying neural activity accompanying alterations in the sense of time and space would be related to alterations in bodily processing. The participants were asked to volitionally bring about distinct states of “Timelessness” (outside time) and “Spacelessness” (outside space) while their brain activity was recorded by MEG. In order to rule out the involvement of attention, memory, or imagination, we used control states of “Then” (past) and “There” (another place). MEG sensors evidencing alterations in power values were identified, and the brain regions underlying these changes were estimated via spatial filtering (beamforming). Particularly, we searched for similar neural activity hypothesized to underlie both the state of “Timelessness” and “Spacelessness.” The results were mostly confined to the theta band, and showed that: (1) the “Then”/“There” overlap yielded activity in regions related to autobiographic memory and imagery (right posterior parietal lobule (PPL), right precentral/middle frontal gyrus (MFG), bilateral precuneus); (2) “Timelessness”/“Spacelessness” conditions overlapped in a different network, related to alterations in the sense of the body (posterior cingulate, right temporoparietal junction (TPJ), cerebellum); and (3) phenomenologically-guided neural analyses enabled us to dissociate different levels of alterations in the sense of the body. This study illustrates the utility of employing experienced contemplative practitioners within a neurophenomenological setup for scientifically characterizing a self-induced altered sense of time, space and body, as well as the importance of theta activity in relation with these altered states.
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Affiliation(s)
| | - Yair Dor-Ziderman
- The Leslie and Susan Gonda (Goldschmied) Multidisciplinary Brain Research Center, Bar-Ilan University Ramat Gan, Israel
| | - Joseph Glicksohn
- The Leslie and Susan Gonda (Goldschmied) Multidisciplinary Brain Research Center, Bar-Ilan University Ramat Gan, Israel ; Department of Criminology, Bar-Ilan University Ramat Gan, Israel
| | - Abraham Goldstein
- The Leslie and Susan Gonda (Goldschmied) Multidisciplinary Brain Research Center, Bar-Ilan University Ramat Gan, Israel ; Department of Psychology, Bar-Ilan University Ramat Gan, Israel
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Hewett R, Bartolomei F. Epilepsy and the cortical vestibular system: tales of dizziness and recent concepts. Front Integr Neurosci 2013; 7:73. [PMID: 24273498 PMCID: PMC3822407 DOI: 10.3389/fnint.2013.00073] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2013] [Accepted: 10/09/2013] [Indexed: 11/13/2022] Open
Abstract
Cortical representations of the vestibular system are now well recognized. In contrast, the fact that epilepsy can affect these systems, provoking transient vestibular symptoms, is less known. Focal seizures may nonetheless manifest by prominent vestibular changes ranging from mild unsteadiness to true rotational vertigo. Most often these symptoms are associated with other subjective manifestations. In pure vestibular forms, the diagnosis may be more difficult and is often delayed. The cortical origin of these symptoms will be discussed and compared with the known "vestibular" cortical representations. In addition, the existence of a specific "vestibular epilepsy" has been suggested in some publications. This condition affects young subjects with a frequent family history and most often a benign evolution, raising the possibility of a form of idiopathic epilepsy (Hewett etal., 2011).
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Affiliation(s)
- Russell Hewett
- Department of Neurology and Neurophysiology, Institute of Neurological Sciences, Southern General Hospital Glasgow, UK
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Pitzalis S, Fattori P, Galletti C. The functional role of the medial motion area V6. Front Behav Neurosci 2013; 6:91. [PMID: 23335889 PMCID: PMC3546310 DOI: 10.3389/fnbeh.2012.00091] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2012] [Accepted: 12/19/2012] [Indexed: 11/13/2022] Open
Abstract
In macaque, several visual areas are devoted to analyze motion in the visual field, and V6 is one of these areas. In macaque, area V6 occupies the ventral part of the anterior bank of the parieto-occipital sulcus (POs), is retinotopically-organized and contains a point-to-point representation of the retinal surface. V6 is a motion sensitive area that largely represents the peripheral part of the visual field and whose cells are very sensitive to translational motion. Based on the fact that macaque V6 contains many real-motion cells, it has been suggested that V6 is involved in object-motion recognition. Recently, area V6 has been recognized also in the human brain by neuroimaging and electrophysiological methods. Like macaque V6, human V6 is located in the POs, is retinotopically organized, and represents the entire contralateral hemifield up to the far periphery. Human V6, like macaque V6, is a motion area that responds to unidirectional motion. It has a strong preference for coherent motion and a recent combined VEPs/fMRI work has shown that area V6 is even one of the most early stations coding the motion coherence. Human V6 is highly sensitive to flow field and is also able to distinguish between different 3D flow fields being selective to translational egomotion. This suggests that this area processes visual egomotion signals to extract information about the relative distance of objects, likely in order to act on them, or to avoid them. The view that V6 is involved in the estimation of egomotion has been tested also in other recent fMRI studies. Thus, taken together, human and macaque data suggest that V6 is involved in both object and self-motion recognition. Specifically, V6 could be involved in "subtracting out" self-motion signals across the whole visual field and in providing information about moving objects, particularly during self-motion in a complex and dynamically unstable environment.
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Affiliation(s)
- Sabrina Pitzalis
- Department of Education in Sport and Human Movement, University of Rome "Foro Italico" Rome, Italy ; Laboratory of Neuropsychology, Santa Lucia Foundation Rome, Italy
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Abdollahi RO, Jastorff J, Orban GA. Common and Segregated Processing of Observed Actions in Human SPL. Cereb Cortex 2012; 23:2734-53. [PMID: 22918981 DOI: 10.1093/cercor/bhs264] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Rouhollah O Abdollahi
- Laboratorium voor Neuro-en Psychofysiologie, KU Leuven Medical School, Leuven, Belgium and
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Cardin V, Hemsworth L, Smith AT. Adaptation to heading direction dissociates the roles of human MST and V6 in the processing of optic flow. J Neurophysiol 2012; 108:794-801. [PMID: 22592304 DOI: 10.1152/jn.00002.2012] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The extraction of optic flow cues is fundamental for successful locomotion. During forward motion, the focus of expansion (FoE), in conjunction with knowledge of eye position, indicates the direction in which the individual is heading. Therefore, it is expected that cortical brain regions that are involved in the estimation of heading will be sensitive to this feature. To characterize cortical sensitivity to the location of the FoE or, more generally, the center of flow (CoF) during visually simulated self-motion, we carried out a functional MRI (fMRI) adaptation experiment in several human visual cortical areas that are thought to be sensitive to optic flow parameters, namely, V3A, V6, MT/V5, and MST. In each trial, two optic flow patterns were sequentially presented, with the CoF located in either the same or different positions. With an adaptation design, an area sensitive to heading direction should respond more strongly to a pair of stimuli with different CoFs than to stimuli with the same CoF. Our results show such release from adaptation in areas MT/V5 and MST, and to a lesser extent V3A, suggesting the involvement of these areas in the processing of heading direction. The effect could not be explained either by differences in local motion or by attention capture. It was not observed to a significant extent in area V6 or in control area V1. The different patterns of responses observed in MST and V6, areas that are both involved in the processing of egomotion in macaques and humans, suggest distinct roles in the processing of visual cues for self-motion.
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Affiliation(s)
- Velia Cardin
- Department of Psychology, Royal Holloway, University of London, Egham, United Kingdom
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Lopez C, Blanke O, Mast FW. The human vestibular cortex revealed by coordinate-based activation likelihood estimation meta-analysis. Neuroscience 2012; 212:159-79. [PMID: 22516007 DOI: 10.1016/j.neuroscience.2012.03.028] [Citation(s) in RCA: 296] [Impact Index Per Article: 24.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2011] [Revised: 03/14/2012] [Accepted: 03/15/2012] [Indexed: 10/28/2022]
Abstract
The vestibular system contributes to the control of posture and eye movements and is also involved in various cognitive functions including spatial navigation and memory. These functions are subtended by projections to a vestibular cortex, whose exact location in the human brain is still a matter of debate (Lopez and Blanke, 2011). The vestibular cortex can be defined as the network of all cortical areas receiving inputs from the vestibular system, including areas where vestibular signals influence the processing of other sensory (e.g. somatosensory and visual) and motor signals. Previous neuroimaging studies used caloric vestibular stimulation (CVS), galvanic vestibular stimulation (GVS), and auditory stimulation (clicks and short-tone bursts) to activate the vestibular receptors and localize the vestibular cortex. However, these three methods differ regarding the receptors stimulated (otoliths, semicircular canals) and the concurrent activation of the tactile, thermal, nociceptive and auditory systems. To evaluate the convergence between these methods and provide a statistical analysis of the localization of the human vestibular cortex, we performed an activation likelihood estimation (ALE) meta-analysis of neuroimaging studies using CVS, GVS, and auditory stimuli. We analyzed a total of 352 activation foci reported in 16 studies carried out in a total of 192 healthy participants. The results reveal that the main regions activated by CVS, GVS, or auditory stimuli were located in the Sylvian fissure, insula, retroinsular cortex, fronto-parietal operculum, superior temporal gyrus, and cingulate cortex. Conjunction analysis indicated that regions showing convergence between two stimulation methods were located in the median (short gyrus III) and posterior (long gyrus IV) insula, parietal operculum and retroinsular cortex (Ri). The only area of convergence between all three methods of stimulation was located in Ri. The data indicate that Ri, parietal operculum and posterior insula are vestibular regions where afferents converge from otoliths and semicircular canals, and may thus be involved in the processing of signals informing about body rotations, translations and tilts. Results from the meta-analysis are in agreement with electrophysiological recordings in monkeys showing main vestibular projections in the transitional zone between Ri, the insular granular field (Ig), and SII.
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Affiliation(s)
- C Lopez
- Department of Psychology, University of Bern, Bern, Switzerland.
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Lopez C, Blanke O. The thalamocortical vestibular system in animals and humans. ACTA ACUST UNITED AC 2011; 67:119-46. [PMID: 21223979 DOI: 10.1016/j.brainresrev.2010.12.002] [Citation(s) in RCA: 371] [Impact Index Per Article: 28.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2010] [Revised: 12/27/2010] [Accepted: 12/30/2010] [Indexed: 02/06/2023]
Abstract
The vestibular system provides the brain with sensory signals about three-dimensional head rotations and translations. These signals are important for postural and oculomotor control, as well as for spatial and bodily perception and cognition, and they are subtended by pathways running from the vestibular nuclei to the thalamus, cerebellum and the "vestibular cortex." The present review summarizes current knowledge on the anatomy of the thalamocortical vestibular system and discusses data from electrophysiology and neuroanatomy in animals by comparing them with data from neuroimagery and neurology in humans. Multiple thalamic nuclei are involved in vestibular processing, including the ventroposterior complex, the ventroanterior-ventrolateral complex, the intralaminar nuclei and the posterior nuclear group (medial and lateral geniculate nuclei, pulvinar). These nuclei contain multisensory neurons that process and relay vestibular, proprioceptive and visual signals to the vestibular cortex. In non-human primates, the parieto-insular vestibular cortex (PIVC) has been proposed as the core vestibular region. Yet, vestibular responses have also been recorded in the somatosensory cortex (area 2v, 3av), intraparietal sulcus, posterior parietal cortex (area 7), area MST, frontal cortex, cingulum and hippocampus. We analyze the location of the corresponding regions in humans, and especially the human PIVC, by reviewing neuroimaging and clinical work. The widespread vestibular projections to the multimodal human PIVC, somatosensory cortex, area MST, intraparietal sulcus and hippocampus explain the large influence of vestibular signals on self-motion perception, spatial navigation, internal models of gravity, one's body perception and bodily self-consciousness.
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Affiliation(s)
- Christophe Lopez
- Laboratory of Cognitive Neuroscience, Brain-Mind Institute, Ecole Polytechnique Fédérale de Lausanne, Swiss Federal Institute of Technology, Lausanne, Switzerland.
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Cardin V, Smith AT. Sensitivity of human visual and vestibular cortical regions to egomotion-compatible visual stimulation. ACTA ACUST UNITED AC 2009; 20:1964-73. [PMID: 20034998 DOI: 10.1093/cercor/bhp268] [Citation(s) in RCA: 141] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
The analysis and representation of visual cues to self-motion (egomotion) is primarily associated with cortical areas MST, VIP, and (recently) cingulate sulcus visual area (CSv). Various other areas, including visual areas V6 and V6A, and vestibular areas parietoinsular vestibular cortex (PIVC), putative area 2v (p2v), and 3aNv, are also potentially suited to processing egomotion (in some cases based on multisensory cues), but it is not known whether they are in fact involved in this process. In a functional magnetic resonance imaging (fMRI) experiment, we presented human participants with 2 types of random dot kinematograms. Both contained coherent motion but one simulated egomotion while the other did not. An area in the parieto-occipital sulcus that may correspond to V6, PIVC, and p2v were all differentially responsive to egomotion-compatible visual stimuli, suggesting that they may be involved in encoding egomotion. More generally, we show that the use of such stimuli provides a simple and reliable fMRI localizer for human PIVC and p2v, which hitherto required galvanic or caloric stimulation to be identified.
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Affiliation(s)
- Velia Cardin
- Department of Psychology, Royal Holloway, University of London, Egham, Surrey TW20 0EX, UK
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Pitzalis S, Sereno MI, Committeri G, Fattori P, Galati G, Patria F, Galletti C. Human v6: the medial motion area. Cereb Cortex 2009; 20:411-24. [PMID: 19502476 PMCID: PMC2803738 DOI: 10.1093/cercor/bhp112] [Citation(s) in RCA: 151] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/05/2022] Open
Abstract
Cortical-surface-based functional Magnetic Resonance Imaging mapping techniques and wide-field retinotopic stimulation were used to verify the presence of pattern motion sensitivity in human area V6. Area V6 is highly selective for coherently moving fields of dots, both at individual and group levels and even with a visual stimulus of standard size. This stimulus is a functional localizer for V6. The wide retinotopic stimuli used here also revealed a retinotopic map in the middle temporal cortex (area MT/V5) surrounded by several polar-angle maps that resemble the mosaic of small areas found around macaque MT/V5. Our results suggest that the MT complex (MT+) may be specialized for the analysis of motion signals, whereas area V6 may be more involved in distinguishing object and self-motion.
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Affiliation(s)
- S Pitzalis
- Department of Education in Sport and Human Movement, University of Rome Foro Italico, 00194 Rome, Italy.
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Spatial updating: how the brain keeps track of changing object locations during observer motion. Nat Neurosci 2008; 11:1223-30. [PMID: 18776895 DOI: 10.1038/nn.2189] [Citation(s) in RCA: 107] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2008] [Accepted: 07/22/2008] [Indexed: 11/09/2022]
Abstract
As you move through an environment, the positions of surrounding objects relative to your body constantly change. Updating these locations is a central feature of situational awareness and readiness to act. Here, we used functional magnetic resonance imaging and a virtual environment to test how the human brain uses optic flow to monitor changing object coordinates. Only activation profiles in the precuneus and the dorsal premotor cortex (PMd) were indicative of an updating process operating on a memorized egocentric map of space. A subsequent eye movement study argued against the alternative explanation that activation in PMd could be driven by oculomotor signals. Finally, introducing a verbal response mode revealed a dissociation between the two regions, with the PMd only showing updating-related responses when participants responded by pointing. We conclude that visual spatial updating relies on the construction of updated representations in the precuneus and the context-dependent planning of motor actions in PMd.
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Kovács G, Raabe M, Greenlee MW. Neural correlates of visually induced self-motion illusion in depth. ACTA ACUST UNITED AC 2007; 18:1779-87. [PMID: 18063566 DOI: 10.1093/cercor/bhm203] [Citation(s) in RCA: 76] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
Optic-flow fields can induce the conscious illusion of self-motion in a stationary observer. Here we used functional magnetic resonance imaging to reveal the differential processing of self- and object-motion in the human brain. Subjects were presented a constantly expanding optic-flow stimulus, composed of disparate red-blue dots, viewed through red-blue glasses to generate a vivid percept of three-dimensional motion. We compared the activity obtained during periods of illusory self-motion with periods of object-motion percept. We found that the right MT+, precuneus, as well as areas located bilaterally along the dorsal part of the intraparietal sulcus and along the left posterior intraparietal sulcus were more active during self-motion perception than during object-motion. Additional signal increases were located in the depth of the left superior frontal sulcus, over the ventral part of the left anterior cingulate, in the depth of the right central sulcus and in the caudate nucleus/putamen. We found no significant deactivations associated with self-motion perception. Our results suggest that the illusory percept of self-motion is correlated with the activation of a network of areas, ranging from motion-specific areas to regions involved in visuo-vestibular integration, visual imagery, decision making, and introspection.
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Affiliation(s)
- Gyula Kovács
- Institute of Psychology, University of Regensburg, 93053 Regensburg, Germany
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Cavanna AE, Trimble MR. The precuneus: a review of its functional anatomy and behavioural correlates. ACTA ACUST UNITED AC 2006; 129:564-83. [PMID: 16399806 DOI: 10.1093/brain/awl004] [Citation(s) in RCA: 3542] [Impact Index Per Article: 196.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Functional neuroimaging studies have started unravelling unexpected functional attributes for the posteromedial portion of the parietal lobe, the precuneus. This cortical area has traditionally received little attention, mainly because of its hidden location and the virtual absence of focal lesion studies. However, recent functional imaging findings in healthy subjects suggest a central role for the precuneus in a wide spectrum of highly integrated tasks, including visuo-spatial imagery, episodic memory retrieval and self-processing operations, namely first-person perspective taking and an experience of agency. Furthermore, precuneus and surrounding posteromedial areas are amongst the brain structures displaying the highest resting metabolic rates (hot spots) and are characterized by transient decreases in the tonic activity during engagement in non-self-referential goal-directed actions (default mode of brain function). Therefore, it has recently been proposed that precuneus is involved in the interwoven network of the neural correlates of self-consciousness, engaged in self-related mental representations during rest. This hypothesis is consistent with the selective hypometabolism in the posteromedial cortex reported in a wide range of altered conscious states, such as sleep, drug-induced anaesthesia and vegetative states. This review summarizes the current knowledge about the macroscopic and microscopic anatomy of precuneus, together with its wide-spread connectivity with both cortical and subcortical structures, as shown by connectional and neurophysiological findings in non-human primates, and links these notions with the multifaceted spectrum of its behavioural correlates. By means of a critical analysis of precuneus activation patterns in response to different mental tasks, this paper provides a useful conceptual framework for matching the functional imaging findings with the specific role(s) played by this structure in the higher-order cognitive functions in which it has been implicated. Specifically, activation patterns appear to converge with anatomical and connectivity data in providing preliminary evidence for a functional subdivision within the precuneus into an anterior region, involved in self-centred mental imagery strategies, and a posterior region, subserving successful episodic memory retrieval.
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