39 results on '"Ramkiran, Shukti"'
Search Results
2. mGluR5 binding changes during a mismatch negativity task in a multimodal protocol with [11C]ABP688 PET/MR-EEG
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Régio Brambilla, Cláudia, Veselinović, Tanja, Rajkumar, Ravichandran, Mauler, Jörg, Matusch, Andreas, Ruch, Andrej, Orth, Linda, Ramkiran, Shukti, Sbaihat, Hasan, Kaulen, Nicolas, Khudeish, Nibal Yahya, Wyss, Christine, Heekeren, Karsten, Kawohl, Wolfram, Rota Kops, Elena, Tellmann, Lutz, Scheins, Jürgen, Boers, Frank, Neumaier, Bernd, Ermert, Johannes, Lang, Markus, Stüsgen, Stefan, Herzog, Hans, Langen, Karl-Josef, Shah, N. Jon, Lerche, Christoph W., and Neuner, Irene
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- 2022
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3. Structural alterations of the insula in depression patients – A 7-Tesla-MRI study
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Schnellbächer, Gereon J., Rajkumar, Ravichandran, Veselinović, Tanja, Ramkiran, Shukti, Hagen, Jana, Shah, N. Jon, and Neuner, Irene
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- 2022
- Full Text
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4. The interaction effect of high social support and resilience on functional connectivity using seed-based resting-state assessed by 7-Tesla ultra-high field MRI.
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Khudeish, Nibal, Ramkiran, Shukti, Nießen, Dominik, Akkoc Altinok, Dilsa Cemre, Rajkumar, Ravichandran, Dammers, Jürgen, Shah, N. Jon, Veselinovic, Tanja, and Neuner, Irene
- Subjects
SOCIAL support ,FUNCTIONAL connectivity ,SOCIAL perception ,PATHOLOGICAL psychology ,MAGNETIC resonance imaging ,RADIOLOGIC technology ,PSYCHOLOGICAL resilience - Abstract
Recent resilience research has increasingly emphasized the importance of focusing on investigating the protective factors in mentally healthy populations, complementing the traditional focus on psychopathology. Social support has emerged as a crucial element within the complex interplay of individual and socio-environmental factors that shape resilience. However, the neural underpinnings of the relationship between social support and resilience, particularly in healthy subjects, remain largely unexplored. With advances in neuroimaging techniques, such as ultra-high field MRI at 7T and beyond, researchers can more effectively investigate the neural mechanisms underlying these factors. Thus, our study employed ultra-high field rs-fMRI to explore how social support moderates the relationship between psychological resilience and functional connectivity in a healthy cohort. We hypothesized that enhanced social support would amplify resilience-associated connectivity within neural circuits essential for emotional regulation, cognitive processing, and adaptive problem-solving, signifying a synergistic interaction where strong social networks bolster the neural underpinnings of resilience. (n = 30). Through seed-based functional connectivity analyses and interaction analysis, we aimed to uncover the neural correlates at the interplay of social support and resilience. Our findings indicate that perceived social support significantly (p<0.001) alters functional connectivity in the right and left FP, PCC, and left hippocampus, affirming the pivotal roles of these regions in the brain's resilience network. Moreover, we identified significant moderation effects of social support across various brain regions, each showing unique connectivity patterns. Specifically, the right FP demonstrated a significant interaction effect where high social support levels were linked to increased connectivity with regions involved in socio-cognitive processing, while low social support showed opposite effects. Similar patterns by social support levels were observed in the left FP, with connectivity changes in clusters associated with emotional regulation and cognitive functions. The PCC's connectivity was distinctly influenced by support levels, elucidating its role in emotional and social cognition. Interestingly, the connectivity of the left hippocampus was not significantly impacted by social support levels, indicating a unique pattern within this region. These insights highlight the importance of high social support levels in enhancing the neural foundations of resilience and fostering adaptive neurological responses to environmental challenges. [ABSTRACT FROM AUTHOR]
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- 2024
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5. QRAGE – Simultaneous multiparametric quantitative MRI of water content, T1, T2*, and magnetic susceptibility at ultrahigh field strength
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Zimmermann, Markus, primary, Abbas, Zaheer, additional, Sommer, Yannic, additional, Lewin, Alexander, additional, Ramkiran, Shukti, additional, Felder, Jörg, additional, Worthoff, Wieland, additional, Oros-Peusquens, Ana-Maria, additional, Yun, Seong Dae, additional, and Shah, N. Jon, additional
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- 2024
- Full Text
- View/download PDF
6. Association between urban upbringing and functional brain connectivity in schizophrenia
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Korann, Vittal, primary, Thonse, Umesh, additional, Garani, Ranjini, additional, Jacob, Arpitha, additional, Ramkiran, Shukti, additional, Praharaj, Samir K., additional, Bharath, Rose D., additional, Kumar, Vijay, additional, Varambally, Shivarama, additional, Venkatasubramanian, Ganesan, additional, and Rao, Naren P., additional
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- 2024
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7. Is it possible to predict performance in attention by measuring key metabolites in the PCC with 7T MRS?
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Collee, Maria, primary, Rajkumar, Ravichandran, additional, Farrher, Ezequiel, additional, Hagen, Jana, additional, Ramkiran, Shukti, additional, Schnellbächer, Gereon Johannes, additional, Khudeish, Nibal, additional, Shah, Nadim Joni, additional, Veselinovic, Tanja, additional, and Neuner, Irene, additional
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- 2023
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8. Resting-state anticorrelated networks in Schizophrenia
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Ramkiran, Shukti, Sharma, Abhinav, and Rao, Naren P.
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- 2019
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9. Excitatory–inhibitory balance within EEG microstates and resting-state fMRI networks: assessed via simultaneous trimodal PET–MR–EEG imaging
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Rajkumar, Ravichandran, Régio Brambilla, Cláudia, Veselinović, Tanja, Bierbrier, Joshua, Wyss, Christine, Ramkiran, Shukti, Orth, Linda, Lang, Markus, Rota Kops, Elena, Mauler, Jörg, Scheins, Jürgen, Neumaier, Bernd, Ermert, Johannes, Herzog, Hans, Langen, Karl-Josef, Binkofski, Ferdinand Christoph, Lerche, Christoph, Shah, N. Jon, and Neuner, Irene
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- 2021
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10. QRAGE – Simultaneous multiparametric quantitative MRI at ultrahigh field strength
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Zimmermann, Markus, primary, Abbas, Zaheer, primary, Sommer, Yannic, primary, Lewin, Alexander, primary, Ramkiran, Shukti, primary, Oros-Peusquens, Ana-Maria, primary, Yun, Seong Dae, primary, and Shah, N. Jon, primary
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- 2023
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11. How brain networks tic: Predicting tic severity through rs‐fMRI dynamics in Tourette syndrome
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Ramkiran, Shukti, primary, Veselinović, Tanja, additional, Dammers, Jürgen, additional, Gaebler, Arnim Johannes, additional, Rajkumar, Ravichandran, additional, Shah, N. Jon, additional, and Neuner, Irene, additional
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- 2023
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12. Contribution of cortical layers to human dynamic functional connectivity
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Pais-Roldán, Patricia, primary, Yun, Seong Dae, additional, Ramkiran, Shukti, additional, Veselinović, Tanja, additional, Neuner, Irene, additional, Zimmermann, Markus, additional, Felder, Jörg, additional, and Shah, John N, additional
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- 2023
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13. Phenomena of hypo- and hyperconnectivity in basal ganglia-thalamo-cortical circuits linked to major depression: a 7T fMRI study
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Hagen, Jana, Ramkiran, Shukti, Schnellbächer, Gereon J., Rajkumar, Ravichandran, Collee, Maria, Khudeish, Nibal, Veselinović, Tanja, Shah, N. Jon, and Neuner, Irene
- Abstract
Major depressive disorder (MDD) typically manifests itself in depressed affect, anhedonia, low energy, and additional symptoms. Despite its high global prevalence, its pathophysiology still gives rise to questions. Current research places alterations in functional connectivity among MDD’s most promising biomarkers. However, given the heterogeneity of previous findings, the use of higher-resolution imaging techniques, like ultra-high field (UHF) fMRI (≥7 Tesla, 7T), may offer greater specificity in delineating fundamental impairments. In this study, 7T UHF fMRI scans were conducted on 31 MDD patients and 27 age-gender matched healthy controls to exploratorily contrast cerebral resting-state functional connectivity patterns between both groups. The CONN toolbox was used to generate functional network connectivity (FNC) analysis based on the region of interest (ROI)-to-ROI correlations in order to enable the identification of clusters of significantly different connections. Correction for multiple comparisons was implemented at the cluster level using a false discovery rate (FDR). The analysis revealed three significant clusters differentiating MDD patients and healthy controls. In Clusters 1 and 2, MDD patients exhibited between-network hypoconnectivity in basal ganglia-cortical pathways as well as hyperconnectivity in thalamo-cortical pathways, including several individual ROI-to-ROI connections. In Cluster 3, they showed increased occipital interhemispheric within-network connectivity. These findings suggest that alterations in basal ganglia-thalamo-cortical circuits play a substantial role in the pathophysiology of MDD. Furthermore, they indicate potential MDD-related deficits relating to a combination of perception (vision, audition, and somatosensation) as well as more complex functions, especially social-emotional processing, modulation, and regulation. It is anticipated that these findings might further inform more accurate clinical procedures for addressing MDD.
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- 2024
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14. How brain networks tic: Predicting tic severity through rs‐fMRI dynamics in Tourette syndrome
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Ramkiran, Shukti, Veselinović, Tanja, Dammers, Jürgen, Gaebler, Arnim Johannes, Rajkumar, Ravichandran, Shah, N. Jon, and Neuner, Irene
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ddc:610 - Abstract
Tourette syndrome (TS) is a neuropsychiatric disorder characterized by motor and phonic tics, which several different theories, such as basal ganglia-thalamo-cortical loop dysfunction and amygdala hypersensitivity, have sought to explain. Previous research has shown dynamic changes in the brain prior to tic onset leading to tics, and this study aims to investigate the contribution of network dynamics to them. For this, we have employed three methods of functional connectivity to resting-state fMRI data – namely the static, the sliding window dynamic and the ICA based estimated dynamic; followed by an examination of the static and dynamic network topological properties. A leave-one-out (LOO-) validated regression model with LASSO regularization was used to identify the key predictors. The relevant predictors pointed to dysfunction of the primary motor cortex, the prefrontal-basal ganglia loop and amygdala-mediated visual social processing network. This is in line with a recently proposed social decision-making dysfunction hypothesis, opening new horizons in understanding tic pathophysiology.
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- 2023
15. Enhancing neuroimaging genetics through meta-analysis for Tourette syndrome (ENIGMA-TS)
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Paschou, Peristera, Jin, Yin, Müller-Vahl, Kirsten, Möller, Harald E., Rizzo, Renata, Hoekstra, Pieter J., Roessner, Veit, Mol Debes, Nanette, Worbe, Yulia, Hartmann, Andreas, Mir, Pablo, Cath, Danielle, Neuner, Irene, Eichele, Heike, Zhang, ChenCheng, Lewandowska, Katarzyna, Munchau, Alexander, Verrel, Julius, Musil, Richard, Silk, Tim J., Hanlon, Colleen A., Bihun, Emily D., Brandt, Valerie, Dietrich, Andrea, Forde, Natalie, Ganos, Christos, Greene, Deanna J., Chu, Chunguang, Grothe, Michel J., Hershey, Tamara, Janik, Piotr, Koller, Jonathan M., Martin-Rodriguez, Juan Francisco, Müller, Karsten, Palmucci, Stefano, Prato, Adriana, Ramkiran, Shukti, Saia, Federica, Szejko, Natalia, Torrecuso, Renzo, Tumer, Zeynep, Uhlmann, Anne, Veselinović, Tanja, Wolańczyk, Tomasz, Zouki, Jade-Jocelyne, Jain, Pritesh, Topaloudi, Apostolia, Kaka, Mary, Yang, Zhiyu, Drineas, Petros, Thomopoulos, Sophia I., White, Tonya, Veltman, Dick J., Schmaal, Lianne, Stein, Dan J., Buitelaar, Jan, Franke, Barbara, van den Heuvel, Odile, Jahanshad, Neda, Thompson, Paul M., Black, Kevin J., ENIGMA-TS Working Group, Anatomy and neurosciences, Psychiatry, Amsterdam Neuroscience - Brain Imaging, Amsterdam Neuroscience - Mood, Anxiety, Psychosis, Stress & Sleep, Amsterdam Neuroscience - Compulsivity, Impulsivity & Attention, Amsterdam Neuroscience - Neurodegeneration, Clinical Cognitive Neuropsychiatry Research Program (CCNP), National Institute of Mental Health (US), National Science Foundation (US), Innovative Medicines Initiative, National Institutes of Health (US), Universidad de Sevilla, Lundbeck Foundation, Dagmar Marshall Foundation, Bøhmske Foundation, Hansen Memorial Foundation, Queen Louise’s Children’s Hospital Foundation, King Christian X’s Foundation, and Child and Adolescent Psychiatry / Psychology
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Psychiatry and Mental health ,Neurodevelopmental disorders Donders Center for Medical Neuroscience [Radboudumc 7] ,brain MRI ,neuroimaging ,SDG 3 - Good Health and Well-being ,Brain MRI ,Tourette syndrome ,Genetics ,ENIGMA ,Neuroimaging ,genetics ,ddc:610 - Abstract
Tourette syndrome (TS) is characterized by multiple motor and vocal tics, and high-comorbidity rates with other neuropsychiatric disorders. Obsessive compulsive disorder (OCD), attention deficit hyperactivity disorder (ADHD), autism spectrum disorders (ASDs), major depressive disorder (MDD), and anxiety disorders (AXDs) are among the most prevalent TS comorbidities. To date, studies on TS brain structure and function have been limited in size with efforts mostly fragmented. This leads to low-statistical power, discordant results due to differences in approaches, and hinders the ability to stratify patients according to clinical parameters and investigate comorbidity patterns. Here, we present the scientific premise, perspectives, and key goals that have motivated the establishment of the Enhancing Neuroimaging Genetics through Meta-Analysis for TS (ENIGMA-TS) working group. The ENIGMA-TS working group is an international collaborative effort bringing together a large network of investigators who aim to understand brain structure and function in TS and dissect the underlying neurobiology that leads to observed comorbidity patterns and clinical heterogeneity. Previously collected TS neuroimaging data will be analyzed jointly and integrated with TS genomic data, as well as equivalently large and already existing studies of highly comorbid OCD, ADHD, ASD, MDD, and AXD. Our work highlights the power of collaborative efforts and transdiagnostic approaches, and points to the existence of different TS subtypes. ENIGMA-TS will offer large-scale, high-powered studies that will lead to important insights toward understanding brain structure and function and genetic effects in TS and related disorders, and the identification of biomarkers that could help inform improved clinical practice., This work was supported by NIMH grant no. 1R01MH126213 and NSF IIS grant no. 1715202 to PP, the Innovative Medicines Initiative 2 Joint Undertaking (grant no. 777394) to NF, the NIH (grant nos. R01MH118217 and K01MH104592) to DG, the NIH (grant nos. R01MH126213, R01MH116147, and P41EB015922) to NJ, the VI-PPIT-US from the University of Seville (grant no. USE-18817-A) to JM-R, the Lundbeck Foundation, the Dagmar Marshall Foundation, the Bøhmske Foundation, the Carpenter Jørgen Holm, and wife Elisa born Hansen Memorial Foundation, the Queen Louise’s Children’s Hospital Foundation, and the King Christian X Foundation to NM, the NIH (grant nos. R01MH126213, R01MH116147, and P41EB015922) to PT and ST.
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- 2022
16. ENIGMA-TS: a worldwide platform for collaboration on the study of Tourette Syndrome genetics and neuroimaging
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Paschou, Peristera, Jin, Yin, Müller-Vahl, Kirsten, Möller, Harald, Rizzo, Renata, Hoekstra, Pieter, Roessner, Veit, Mol Debes, Nanette, Worbe, Yulia, Hartmann, Andreas, Mir, Pablo, Cath, Danielle, Neuner, Irene, Eichele, Heike, Zhang, Chencheng, Szamburska-Lewandowska, Katarzyna, Muenchau, Alexander, Verrel, Julius, Musil, Richard, Silk, Tim, Hanlon, Colleen, Bihun, Emily, Brandt, Valerie, Dietrick, Andrea, Forde, Natalie, Ganos, Christos, Greene, Deanna, Chunguang, Chu, Grothe, Michel, Hershey, Tamara, Janik, Piotr, Koller, Jonathan, Rodriguez, Juan Francisco Martin, Mueller, Karsten, Palmucci, Stefano, Prato, Adriana, Ramkiran, Shukti, Saia, Federica, Szejko, Natalia, Torrecuso, Renzo, Tumer, Zeynep, Uhlmann, Anne, Veselinovic, Tanja, Wolanczyk, Tomasz, Zouki, Jace, Jain, Pritesh, Topaloudi, Apostolia, Kaka, Mary, Yang, Zhiyu, Drineas, Petros, Thomopoulos, Sophia, White, Tonya, Veltman, Dick, Schmaal, Lianne, Stein, Dan, Franke, Barbara, van den Heuvel, Odile, Jahanshad, Neda, Thompson, Paul, and Black, Kevin
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- 2022
17. Analysis of New Biomarkers for the Study of Schizophrenia Following a Radiomics Approach on MR and PET Imaging
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Carrasco-Poves, Alejandro, primary, Ruiz-Espana, Silvia, additional, Brambilla, Claudia Regio, additional, Neuner, Irene, additional, Rajkumar, Ravichandran, additional, Ramkiran, Shukti, additional, Lerche, Christoph, additional, and Moratal, David, additional
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- 2022
- Full Text
- View/download PDF
18. How brain networks tic: predicting tic severity through rs-fMRI dynamics in Tourette syndrome
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Ramkiran, Shukti, primary, Veselinović, Tanja, additional, Dammers, Jürgen, additional, Rajkumar, Ravichandran, additional, Shah, Jon, additional, and Neuner, Irene, additional
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- 2022
- Full Text
- View/download PDF
19. Enhancing neuroimaging genetics through meta-analysis for Tourette syndrome (ENIGMA-TS):A worldwide platform for collaboration
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Paschou, Peristera, Jin, Yin, Müller-Vahl, Kirsten, Möller, Harald E., Rizzo, Renata, Hoekstra, Pieter J., Roessner, Veit, Debes, Nanette Mol, Worbe, Yulia, Hartmann, Andreas, Mir, Pablo, Cath, Danielle, Neuner, Irene, Eichele, Heike, Zhang, Chencheng, Lewandowska, Katarzyna, Munchau, Alexander, Verrel, Julius, Musil, Richard, Silk, Tim J., Hanlon, Colleen A., Bihun, Emily D., Brandt, Valerie, Dietrich, Andrea, Forde, Natalie, Ganos, Christos, Greene, Deanna J., Chu, Chunguang, Grothe, Michel J, Hershey, Tamara, Janik, Piotr, Koller, Jonathan M., Martin-Rodriguez, Juan Francisco, Müller, Karsten, Palmucci, Stefano, Prato, Adriana, Ramkiran, Shukti, Saia, Federica, Szejko, Natalia, Torrecuso, Renzo, Tumer, Zeynep, Uhlmann, Anne, Veselinovic, Tanja, Wolańczyk, Tomasz, Zouki, Jade Jocelyne, Jain, Pritesh, Topaloudi, Apostolia, Kaka, Mary, Yang, Zhiyu, Drineas, Petros, Thomopoulos, Sophia I., White, Tonya, Veltman, Dick J, Schmaal, Lianne, Stein, Dan J, Buitelaar, Jan, Franke, Barbara, van den Heuvel, Odile, Jahanshad, Neda, Thompson, Paul M., Black, Kevin J., Paschou, Peristera, Jin, Yin, Müller-Vahl, Kirsten, Möller, Harald E., Rizzo, Renata, Hoekstra, Pieter J., Roessner, Veit, Debes, Nanette Mol, Worbe, Yulia, Hartmann, Andreas, Mir, Pablo, Cath, Danielle, Neuner, Irene, Eichele, Heike, Zhang, Chencheng, Lewandowska, Katarzyna, Munchau, Alexander, Verrel, Julius, Musil, Richard, Silk, Tim J., Hanlon, Colleen A., Bihun, Emily D., Brandt, Valerie, Dietrich, Andrea, Forde, Natalie, Ganos, Christos, Greene, Deanna J., Chu, Chunguang, Grothe, Michel J, Hershey, Tamara, Janik, Piotr, Koller, Jonathan M., Martin-Rodriguez, Juan Francisco, Müller, Karsten, Palmucci, Stefano, Prato, Adriana, Ramkiran, Shukti, Saia, Federica, Szejko, Natalia, Torrecuso, Renzo, Tumer, Zeynep, Uhlmann, Anne, Veselinovic, Tanja, Wolańczyk, Tomasz, Zouki, Jade Jocelyne, Jain, Pritesh, Topaloudi, Apostolia, Kaka, Mary, Yang, Zhiyu, Drineas, Petros, Thomopoulos, Sophia I., White, Tonya, Veltman, Dick J, Schmaal, Lianne, Stein, Dan J, Buitelaar, Jan, Franke, Barbara, van den Heuvel, Odile, Jahanshad, Neda, Thompson, Paul M., and Black, Kevin J.
- Abstract
Tourette syndrome (TS) is characterized by multiple motor and vocal tics, and high-comorbidity rates with other neuropsychiatric disorders. Obsessive compulsive disorder (OCD), attention deficit hyperactivity disorder (ADHD), autism spectrum disorders (ASDs), major depressive disorder (MDD), and anxiety disorders (AXDs) are among the most prevalent TS comorbidities. To date, studies on TS brain structure and function have been limited in size with efforts mostly fragmented. This leads to low-statistical power, discordant results due to differences in approaches, and hinders the ability to stratify patients according to clinical parameters and investigate comorbidity patterns. Here, we present the scientific premise, perspectives, and key goals that have motivated the establishment of the Enhancing Neuroimaging Genetics through Meta-Analysis for TS (ENIGMA-TS) working group. The ENIGMA-TS working group is an international collaborative effort bringing together a large network of investigators who aim to understand brain structure and function in TS and dissect the underlying neurobiology that leads to observed comorbidity patterns and clinical heterogeneity. Previously collected TS neuroimaging data will be analyzed jointly and integrated with TS genomic data, as well as equivalently large and already existing studies of highly comorbid OCD, ADHD, ASD, MDD, and AXD. Our work highlights the power of collaborative efforts and transdiagnostic approaches, and points to the existence of different TS subtypes. ENIGMA-TS will offer large-scale, high-powered studies that will lead to important insights toward understanding brain structure and function and genetic effects in TS and related disorders, and the identification of biomarkers that could help inform improved clinical practice.
- Published
- 2022
20. Enhancing neuroimaging genetics through meta-analysis for Tourette syndrome (ENIGMA-TS): A worldwide platform for collaboration
- Author
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National Institute of Mental Health (US), National Science Foundation (US), Innovative Medicines Initiative, National Institutes of Health (US), Universidad de Sevilla, Lundbeck Foundation, Dagmar Marshall Foundation, Bohemia Fund, Jeff Hansen Memorial Foundation, Queen Louise's Children's Hospital Foundation, King Christian X’s Foundation, Paschou, Peristera, Jin, Yin, Müller-Vahl, Kirsten R., Möller, Harald E., Rizzo, Renata, Hoekstra, Pieter J., Roessner, Veit, Mol Debes, Nanette, Worbe, Yulia, Hartmann, Andreas, Mir, Pablo, Cath, Danielle, Neuner, Irene, Eichele, Heike, Zhang, Chencheng, Lewandowska, Katarzyna, Münchau, Alexander, Verrel, Julius, Musil, Richard, Silk, Tim J., Hanlon, Colleen A., Bihun, Emily D., Brandt, Valerie, Dietrich, Andrea, Forde, Natalie, Ganos, Christos, Greene, Deanna J., Chu, Chunguang, Grothe, Michel J., Hershey, Tamara, Janik, Piotr, Koller, Jonathan M., Martín-Rodríguez, Juan Francisco, Müller, Karsten, Palmucci, Stefano, Prato, Adriana, Ramkiran, Shukti, Saia, Federica, Szejko, Natalia, Torrecuso, Renzo, Tumer, Zeynep, Uhlmann, Anne, Veselinovic, Tanja, Wolańczyk, Tomasz, Zouki, Jade Jocelyne, Jain, Pritesh, Topaloudi, Apostolia, Kaka, Mary, Yang, Zhiyu, Drineas, Petros, Thomopoulos, Sophia I., White, Tonya, Veltman, Dick J., Schmaal, Lianne, Stein, Dan J., Buitelaar, Jan, Franke, Barbara, Heuvel, Odile van den, Jahanshad, Neda, Thompson, Paul M., Black, Kevin J., National Institute of Mental Health (US), National Science Foundation (US), Innovative Medicines Initiative, National Institutes of Health (US), Universidad de Sevilla, Lundbeck Foundation, Dagmar Marshall Foundation, Bohemia Fund, Jeff Hansen Memorial Foundation, Queen Louise's Children's Hospital Foundation, King Christian X’s Foundation, Paschou, Peristera, Jin, Yin, Müller-Vahl, Kirsten R., Möller, Harald E., Rizzo, Renata, Hoekstra, Pieter J., Roessner, Veit, Mol Debes, Nanette, Worbe, Yulia, Hartmann, Andreas, Mir, Pablo, Cath, Danielle, Neuner, Irene, Eichele, Heike, Zhang, Chencheng, Lewandowska, Katarzyna, Münchau, Alexander, Verrel, Julius, Musil, Richard, Silk, Tim J., Hanlon, Colleen A., Bihun, Emily D., Brandt, Valerie, Dietrich, Andrea, Forde, Natalie, Ganos, Christos, Greene, Deanna J., Chu, Chunguang, Grothe, Michel J., Hershey, Tamara, Janik, Piotr, Koller, Jonathan M., Martín-Rodríguez, Juan Francisco, Müller, Karsten, Palmucci, Stefano, Prato, Adriana, Ramkiran, Shukti, Saia, Federica, Szejko, Natalia, Torrecuso, Renzo, Tumer, Zeynep, Uhlmann, Anne, Veselinovic, Tanja, Wolańczyk, Tomasz, Zouki, Jade Jocelyne, Jain, Pritesh, Topaloudi, Apostolia, Kaka, Mary, Yang, Zhiyu, Drineas, Petros, Thomopoulos, Sophia I., White, Tonya, Veltman, Dick J., Schmaal, Lianne, Stein, Dan J., Buitelaar, Jan, Franke, Barbara, Heuvel, Odile van den, Jahanshad, Neda, Thompson, Paul M., and Black, Kevin J.
- Abstract
Tourette syndrome (TS) is characterized by multiple motor and vocal tics, and high-comorbidity rates with other neuropsychiatric disorders. Obsessive compulsive disorder (OCD), attention deficit hyperactivity disorder (ADHD), autism spectrum disorders (ASDs), major depressive disorder (MDD), and anxiety disorders (AXDs) are among the most prevalent TS comorbidities. To date, studies on TS brain structure and function have been limited in size with efforts mostly fragmented. This leads to low-statistical power, discordant results due to differences in approaches, and hinders the ability to stratify patients according to clinical parameters and investigate comorbidity patterns. Here, we present the scientific premise, perspectives, and key goals that have motivated the establishment of the Enhancing Neuroimaging Genetics through Meta-Analysis for TS (ENIGMA-TS) working group. The ENIGMA-TS working group is an international collaborative effort bringing together a large network of investigators who aim to understand brain structure and function in TS and dissect the underlying neurobiology that leads to observed comorbidity patterns and clinical heterogeneity. Previously collected TS neuroimaging data will be analyzed jointly and integrated with TS genomic data, as well as equivalently large and already existing studies of highly comorbid OCD, ADHD, ASD, MDD, and AXD. Our work highlights the power of collaborative efforts and transdiagnostic approaches, and points to the existence of different TS subtypes. ENIGMA-TS will offer large-scale, high-powered studies that will lead to important insights toward understanding brain structure and function and genetic effects in TS and related disorders, and the identification of biomarkers that could help inform improved clinical practice.
- Published
- 2022
21. mGluR5 and GABAA receptor-specific parametric PET atlas construction-PET/MR data processing pipeline, validation, and application
- Author
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Kaulen, Nicolas, Rajkumar, Ravichandran, Régio Brambilla, Cláudia, Mauler, Jörg, Ramkiran, Shukti, Orth, Linda, Sbaihat, Hasan, Lang, Markus, Wyss, Christine, Rota Kops, Elena, Scheins, Jürgen, Neumaier, Bernd, Ermert, Johannes, Herzog, Hans, Langen, Karl-Joseph, Lerche, Christoph, Shah, Nadim Joni, Veselinović, Tanja, and Neuner, Irene
- Abstract
Human brain mapping 43(7), 2148-2163 (2022). doi:10.1002/hbm.25778, Published by Wiley-Liss, New York, NY
- Published
- 2022
22. mGluR 5 and GABA A receptor‐specific parametric PET atlas construction— PET / MR data processing pipeline, validation, and application
- Author
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Kaulen, Nicolas, Rajkumar, Ravichandran, Scheins, Jürgen, Neumaier, Bernd, Ermert, Johannes, Herzog, Hans, Langen, Karl-Joseph, Lerche, Christoph, Shah, N. J., Veselinović, Tanja, Neuner, Irene, Régio Brambilla, Cláudia, Mauler, Jörg, Ramkiran, Shukti, Orth, Linda, Sbaihat, Hasan, Lang, Markus, Wyss, Christine, and Rota Kops, Elena
- Subjects
ddc:610 - Abstract
The glutamate and γ-aminobutyric acid neuroreceptor subtypes mGluR5 and GABAA are hypothesized to be involved in the development of a variety of psychiatric diseases. However, detailed information relating to their in vivo distribution is generally unavailable. Maps of such distributions could potentially aid clinical studies by providing a reference for the normal distribution of neuroreceptors and may also be useful as covariates in advanced functional magnetic resonance imaging (MR) studies. In this study, we propose a comprehensive processing pipeline for the construction of standard space, in vivo distributions of non-displaceable binding potential (BPND), and total distribution volume (VT) based on simultaneously acquired bolus-infusion positron emission tomography (PET) and MR data. The pipeline was applied to [11C]ABP688-PET/MR (13 healthy male non-smokers, 26.6 ± 7.0 years) and [11C]Flumazenil-PET/MR (10 healthy males, 25.8 ± 3.0 years) data. Activity concentration templates, as well as VT and BPND atlases of mGluR5 and GABAA, were generated from these data. The maps were validated by assessing the percent error δ from warped space to native space in a selection of brain regions. We verified that the average δABP = 3.0 ± 1.0% and δFMZ = 3.8 ± 1.4% were lower than the expected variabilities σ of the tracers (σABP = 4.0%–16.0%, σFMZ = 3.9%–9.5%). An evaluation of PET-to-PET registrations based on the new maps showed higher registration accuracy compared to registrations based on the commonly used [15O]H2O-template distributed with SPM12. Thus, we conclude that the resulting maps can be used for further research and the proposed pipeline is a viable tool for the construction of standardized PET data distributions.
- Published
- 2022
23. Test–retest stability of spontaneous brain activity and functional connectivity in the core resting-state networks assessed with ultrahigh field 7-Tesla resting-state functional magnetic resonance imaging
- Author
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Sbaihat, Hasan, Rajkumar, Ravichandran, Ramkiran, Shukti, Assi, Abed Al-Nasser, Felder, Jörg, Shah, Nadim Joni, Veselinović, Tanja, and Neuner, Irene
- Subjects
Brain Mapping ,Brain ,Humans ,Reproducibility of Results ,ddc:610 ,Nerve Net ,Magnetic Resonance Imaging - Abstract
Human brain mapping 43(6), 2026-2040 (2022). doi:10.1002/hbm.25771, Published by Wiley-Liss, New York, NY
- Published
- 2022
24. mGluR5 and GABAA receptor‐specific parametric PET atlas construction—PET/MR data processing pipeline, validation, and application
- Author
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Kaulen, Nicolas, primary, Rajkumar, Ravichandran, additional, Régio Brambilla, Cláudia, additional, Mauler, Jörg, additional, Ramkiran, Shukti, additional, Orth, Linda, additional, Sbaihat, Hasan, additional, Lang, Markus, additional, Wyss, Christine, additional, Rota Kops, Elena, additional, Scheins, Jürgen, additional, Neumaier, Bernd, additional, Ermert, Johannes, additional, Herzog, Hans, additional, Langen, Karl‐Joseph, additional, Lerche, Christoph, additional, Shah, N. Jon, additional, Veselinović, Tanja, additional, and Neuner, Irene, additional
- Published
- 2022
- Full Text
- View/download PDF
25. Test–retest stability of spontaneous brain activity and functional connectivity in the core resting‐state networks assessed with ultrahigh field 7‐Tesla resting‐state functional magnetic resonance imaging
- Author
-
Sbaihat, Hasan, primary, Rajkumar, Ravichandran, additional, Ramkiran, Shukti, additional, Assi, Abed Al‐Nasser, additional, Felder, Jörg, additional, Shah, Nadim Jon, additional, Veselinović, Tanja, additional, and Neuner, Irene, additional
- Published
- 2022
- Full Text
- View/download PDF
26. Dynamics of task-induced modulation of spontaneous brain activity and functional connectivity in the triple resting-state networks assessed using the visual oddball paradigm
- Author
-
Sbaihat, Hasan, primary, Rajkumar, Ravichandran, additional, Ramkiran, Shukti, additional, Assi, Abed Al-Nasser, additional, Shah, N. Jon, additional, Veselinović, Tanja, additional, and Neuner, Irene, additional
- Published
- 2021
- Full Text
- View/download PDF
27. mGluR5 and GABAA receptor‐specific parametric PET atlas construction—PET/MR data processing pipeline, validation, and application.
- Author
-
Kaulen, Nicolas, Rajkumar, Ravichandran, Régio Brambilla, Cláudia, Mauler, Jörg, Ramkiran, Shukti, Orth, Linda, Sbaihat, Hasan, Lang, Markus, Wyss, Christine, Rota Kops, Elena, Scheins, Jürgen, Neumaier, Bernd, Ermert, Johannes, Herzog, Hans, Langen, Karl‐Joseph, Lerche, Christoph, Shah, N. Jon, Veselinović, Tanja, and Neuner, Irene
- Subjects
FUNCTIONAL magnetic resonance imaging ,POSITRON emission tomography ,ELECTRONIC data processing - Abstract
The glutamate and γ‐aminobutyric acid neuroreceptor subtypes mGluR5 and GABAA are hypothesized to be involved in the development of a variety of psychiatric diseases. However, detailed information relating to their in vivo distribution is generally unavailable. Maps of such distributions could potentially aid clinical studies by providing a reference for the normal distribution of neuroreceptors and may also be useful as covariates in advanced functional magnetic resonance imaging (MR) studies. In this study, we propose a comprehensive processing pipeline for the construction of standard space, in vivo distributions of non‐displaceable binding potential (BPND), and total distribution volume (VT) based on simultaneously acquired bolus‐infusion positron emission tomography (PET) and MR data. The pipeline was applied to [11C]ABP688‐PET/MR (13 healthy male non‐smokers, 26.6 ± 7.0 years) and [11C]Flumazenil‐PET/MR (10 healthy males, 25.8 ± 3.0 years) data. Activity concentration templates, as well as VT and BPND atlases of mGluR5 and GABAA, were generated from these data. The maps were validated by assessing the percent error δ from warped space to native space in a selection of brain regions. We verified that the average δABP = 3.0 ± 1.0% and δFMZ = 3.8 ± 1.4% were lower than the expected variabilities σ of the tracers (σABP = 4.0%–16.0%, σFMZ = 3.9%–9.5%). An evaluation of PET‐to‐PET registrations based on the new maps showed higher registration accuracy compared to registrations based on the commonly used [15O]H2O‐template distributed with SPM12. Thus, we conclude that the resulting maps can be used for further research and the proposed pipeline is a viable tool for the construction of standardized PET data distributions. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
28. mGluR5 receptor availability is associated with lower levels of negative symptoms and better cognition in male patients with chronic schizophrenia
- Author
-
Régio Brambilla, Cláudia; https://orcid.org/0000-0002-3735-8511, Veselinović, Tanja; https://orcid.org/0000-0001-7906-6966, Rajkumar, Ravichandran; https://orcid.org/0000-0001-5875-5316, Mauler, Jörg; https://orcid.org/0000-0003-4937-0355, Orth, Linda, Ruch, Andrej; https://orcid.org/0000-0002-0524-347X, Ramkiran, Shukti; https://orcid.org/0000-0001-8253-1873, Heekeren, Karsten; https://orcid.org/0000-0001-5105-1922, Kawohl, Wolfram, Wyss, Christine; https://orcid.org/0000-0003-2088-9794, Kops, Elena Rota; https://orcid.org/0000-0002-0959-9457, Scheins, Jürgen, Tellmann, Lutz, Boers, Frank, Neumaier, Bernd; https://orcid.org/0000-0001-5425-3116, Ermert, Johannes, Herzog, Hans; https://orcid.org/0000-0002-6751-7165, Langen, Karl-Josef; https://orcid.org/0000-0003-1101-5075, Jon Shah, N; https://orcid.org/0000-0002-8151-6169, Lerche, Christoph; https://orcid.org/0000-0003-2749-2108, Neuner, Irene; https://orcid.org/0000-0002-5164-8873, Régio Brambilla, Cláudia; https://orcid.org/0000-0002-3735-8511, Veselinović, Tanja; https://orcid.org/0000-0001-7906-6966, Rajkumar, Ravichandran; https://orcid.org/0000-0001-5875-5316, Mauler, Jörg; https://orcid.org/0000-0003-4937-0355, Orth, Linda, Ruch, Andrej; https://orcid.org/0000-0002-0524-347X, Ramkiran, Shukti; https://orcid.org/0000-0001-8253-1873, Heekeren, Karsten; https://orcid.org/0000-0001-5105-1922, Kawohl, Wolfram, Wyss, Christine; https://orcid.org/0000-0003-2088-9794, Kops, Elena Rota; https://orcid.org/0000-0002-0959-9457, Scheins, Jürgen, Tellmann, Lutz, Boers, Frank, Neumaier, Bernd; https://orcid.org/0000-0001-5425-3116, Ermert, Johannes, Herzog, Hans; https://orcid.org/0000-0002-6751-7165, Langen, Karl-Josef; https://orcid.org/0000-0003-1101-5075, Jon Shah, N; https://orcid.org/0000-0002-8151-6169, Lerche, Christoph; https://orcid.org/0000-0003-2749-2108, and Neuner, Irene; https://orcid.org/0000-0002-5164-8873
- Abstract
Consistent findings postulate disturbed glutamatergic function (more specifically a hypofunction of the ionotropic NMDA receptors) as an important pathophysiologic mechanism in schizophrenia. However, the role of the metabotropic glutamatergic receptors type 5 (mGluR5) in this disease remains unclear. In this study, we investigated their significance (using [11 C]ABP688) for psychopathology and cognition in male patients with chronic schizophrenia and healthy controls. In the patient group, lower mGluR5 binding potential (BPND ) values in the left temporal cortex and caudate were associated with higher general symptom levels (negative and depressive symptoms), lower levels of global functioning and worse cognitive performance. At the same time, in both groups, mGluR5 BPND were significantly lower in smokers (F[27,1] = 15.500; p = .001), but without significant differences between the groups. Our findings provide support for the concept that the impaired function of mGluR5 underlies the symptoms of schizophrenia. They further supply a new perspective on the complex relationship between tobacco addiction and schizophrenia by identifying glutamatergic neurotransmission-in particularly mGluR5-as a possible connection to a shared vulnerability. Keywords: chronic schizophrenia; cognition; mGluR5 receptor; negative symptoms; positron emission tomography.
- Published
- 2020
29. Modulation of the spontaneous brain activity and functional connectivity in the triple resting-state networks following the visual oddball paradigm
- Author
-
Sbaihat, Hasan, primary, Rajkumar, Ravichandran, additional, Ramkiran, Shukti, additional, Assi, Abed Al-Nasser, additional, Shah, N. Jon, additional, Veselinović, Tanja, additional, and Neuner, Irene, additional
- Published
- 2021
- Full Text
- View/download PDF
30. mGluR5 receptor availability is associated with lower levels of negative symptoms and better cognition in male patients with chronic schizophrenia
- Author
-
Régio Brambilla, Cláudia, primary, Veselinović, Tanja, additional, Rajkumar, Ravichandran, additional, Mauler, Jörg, additional, Orth, Linda, additional, Ruch, Andrej, additional, Ramkiran, Shukti, additional, Heekeren, Karsten, additional, Kawohl, Wolfram, additional, Wyss, Christine, additional, Kops, Elena Rota, additional, Scheins, Jürgen, additional, Tellmann, Lutz, additional, Boers, Frank, additional, Neumaier, Bernd, additional, Ermert, Johannes, additional, Herzog, Hans, additional, Langen, Karl‐Josef, additional, Jon Shah, N., additional, Lerche, Christoph, additional, and Neuner, Irene, additional
- Published
- 2020
- Full Text
- View/download PDF
31. mGluR5 binding changes during a mismatch negativity task in a multimodal protocol with [11C]ABP688 PET/MR-EEG.
- Author
-
Régio Brambilla, Cláudia, Veselinović, Tanja, Rajkumar, Ravichandran, Mauler, Jörg, Matusch, Andreas, Ruch, Andrej, Orth, Linda, Ramkiran, Shukti, Sbaihat, Hasan, Kaulen, Nicolas, Khudeish, Nibal Yahya, Wyss, Christine, Heekeren, Karsten, Kawohl, Wolfram, Rota Kops, Elena, Tellmann, Lutz, Scheins, Jürgen, Boers, Frank, Neumaier, Bernd, and Ermert, Johannes
- Published
- 2022
- Full Text
- View/download PDF
32. mGluR5 receptor availability is associated with lower levels of negative symptoms and better cognition in male patients with chronic schizophrenia
- Author
-
Régio Brambilla, Cláudia, Veselinović, Tanja, Rajkumar, Ravichandran, Mauler, Jörg, Orth, Linda, Ruch, Andrej, Ramkiran, Shukti, Heekeren, Karsten, Kawohl, Wolfram, Wyss, Christine, Kops, Elena Rota, Scheins, Jürgen, Tellmann, Lutz, Boers, Frank, Neumaier, Bernd, Ermert, Johannes, Herzog, Hans, Langen, Karl-Josef, Jon Shah, N, Lerche, Christoph, Neuner, Irene, University of Zurich, and Régio Brambilla, Cláudia
- Subjects
Adult ,Male ,cognition ,positron emission tomography ,Pyridines ,Receptor, Metabotropic Glutamate 5 ,610 Medicine & health ,Neuropsychological Tests ,mental disorders ,Oximes ,2741 Radiology, Nuclear Medicine and Imaging ,Humans ,Cognitive Dysfunction ,ddc:610 ,chronic schizophrenia ,3614 Radiological and Ultrasound Technology ,Research Articles ,negative symptoms ,mGluR5 receptor ,Smoking ,Middle Aged ,2702 Anatomy ,Temporal Lobe ,2728 Neurology (clinical) ,10054 Clinic for Psychiatry, Psychotherapy, and Psychosomatics ,2808 Neurology ,Positron-Emission Tomography ,Chronic Disease ,Schizophrenia ,Caudate Nucleus ,Research Article - Abstract
Consistent findings postulate disturbed glutamatergic function (more specifically a hypofunction of the ionotropic NMDA receptors) as an important pathophysiologic mechanism in schizophrenia. However, the role of the metabotropic glutamatergic receptors type 5 (mGluR5) in this disease remains unclear. In this study, we investigated their significance (using [11C]ABP688) for psychopathology and cognition in male patients with chronic schizophrenia and healthy controls. In the patient group, lower mGluR5 binding potential (BPND) values in the left temporal cortex and caudate were associated with higher general symptom levels (negative and depressive symptoms), lower levels of global functioning and worse cognitive performance. At the same time, in both groups, mGluR5 BPND were significantly lower in smokers (F [27,1] = 15.500; p = .001), but without significant differences between the groups. Our findings provide support for the concept that the impaired function of mGluR5 underlies the symptoms of schizophrenia. They further supply a new perspective on the complex relationship between tobacco addiction and schizophrenia by identifying glutamatergic neurotransmission—in particularly mGluR5—as a possible connection to a shared vulnerability.
- Published
- 2019
33. Alterations in basal ganglia-cerebello-thalamo-cortical connectivity and whole brain functional network topology in Tourette's syndrome
- Author
-
Ramkiran, Shukti, Heidemeyer, Larissa, Gaebler, Arnim, Shah, Nadim Joni, and Neuner, Irene
- Subjects
Adult ,Cerebral Cortex ,Connectivity ,Regular Article ,Tourette's syndrome ,lcsh:Computer applications to medicine. Medical informatics ,Magnetic Resonance Imaging ,Basal Ganglia ,Brain network topology ,lcsh:RC346-429 ,Young Adult ,Thalamus ,nervous system ,Cerebellum ,Connectome ,Humans ,lcsh:R858-859.7 ,ddc:610 ,Nerve Net ,lcsh:Neurology. Diseases of the nervous system ,Tourette Syndrome - Abstract
Tourette Syndrome (TS) is a neuropsychiatric disorder characterized by the presence of motor and vocal tics. Major pathophysiological theories posit a dysfunction of the cortico-striato-thalamo-cortical circuits as being a representative hallmark of the disease. Recent evidence suggests a more widespread dysfunction of brain networks in TS including the cerebellum and going even beyond classic motor pathways. In order to characterize brain network dysfunction in TS, in this study we investigated functional and effective-like connectivity as well as topological changes of basal ganglia-thalamo-cortical and cortico-cerebellar brain networks. We collected resting-state fMRI data from 28 TS patients (age: 32 ± 11 years) and 28 age-matched, healthy controls (age: 31 ± 9 years). Region of interest based (ROI-ROI) bivariate correlation and ROI-ROI bivariate regression were employed as measures of functional and effective-like connectivity, respectively. Graph theoretical measures of centrality (degree, cost, betweenness centrality), functional segregation (clustering coefficient, local efficiency) and functional integration (average path length, global efficiency) were used to assess topological brain network changes. In this study, TS patients exhibited increased basal ganglia-cortical and thalamo-cortical connectivity, reduced cortico-cerebellar connectivity, and an increase in parallel communication through the basal ganglia, thalamus and cerebellum (increased global efficiency). Additionally, we observed a reduction in serial information transfer (reduction in average path length) within the default mode and the salience network. In summary, our findings show that TS is characterized by increased connectivity and functional integration of multiple basal ganglia-thalamo-cortical circuits, suggesting a predominance of excitatory neurotransmission and a lack of brain maturation. Moreover, topological changes of cortico-cerebellar and brain networks involved in interoception may be underestimated neural correlates of tics and the crucial premonitory urge feeling., Highlights • Cerebellum shows reduced connectivity with the cortex in Tourette's syndrome (TS). • Basal ganglia and thalamus show increased connectivity with the cortex in TS. • Topological average path length is reduced in several cortical regions in TS. • Topological efficiency is increased in the basal ganglia in TS.
- Published
- 2019
- Full Text
- View/download PDF
34. Alterations in basal ganglia-cerebello-thalamo-cortical connectivity and whole brain functional network topology in Tourette's syndrome
- Author
-
Ramkiran, Shukti, primary, Heidemeyer, Larissa, additional, Gaebler, Arnim, additional, Shah, N. Jon, additional, and Neuner, Irene, additional
- Published
- 2019
- Full Text
- View/download PDF
35. MRI based schizophrenia patient classification: A meta-cognitive approach
- Author
-
Sharma, Abhinav, primary and Ramkiran, Shukti, additional
- Published
- 2015
- Full Text
- View/download PDF
36. High dynamicity of cortical depth-dependent connectivity states
- Author
-
Pais-Roldan, Patricia, primary, Ramkiran, Shukti, additional, Yun, Seong Dae, additional, and Shah, Jon, additional
- Full Text
- View/download PDF
37. QRAGE-Simultaneous multiparametric quantitative MRI of water content, T 1 , T 2 *, and magnetic susceptibility at ultrahigh field strength.
- Author
-
Zimmermann M, Abbas Z, Sommer Y, Lewin A, Ramkiran S, Felder J, Worthoff WA, Oros-Peusquens AM, Yun SD, and Shah NJ
- Abstract
Purpose: To introduce quantitative rapid gradient-echo (QRAGE), a novel approach for the simultaneous mapping of multiple quantitative MRI parameters, including water content, T
1 , T2 *, and magnetic susceptibility at ultrahigh field strength., Methods: QRAGE leverages a newly developed multi-echo MPnRAGE sequence, facilitating the acquisition of 171 distinct contrast images across a range of inversion and TE points. To maintain a short acquisition time, we introduce MIRAGE2, a novel model-based reconstruction method that exploits prior knowledge of temporal signal evolution, represented as damped complex exponentials. MIRAGE2 minimizes local Block-Hankel and Casorati matrices. Parameter maps are derived from the reconstructed contrast images through postprocessing steps. We validate QRAGE through extensive simulations, phantom studies, and in vivo experiments, demonstrating its capability for high-precision imaging., Results: In vivo brain measurements show the promising performance of QRAGE, with test-retest SDs and deviations from reference methods of < 0.8% for water content, < 17 ms for T1 , and < 0.7 ms for T2 *. QRAGE achieves whole-brain coverage at a 1-mm isotropic resolution in just 7 min and 15 s, comparable to the acquisition time of an MP2RAGE scan. In addition, QRAGE generates a contrast image akin to the UNI image produced by MP2RAGE., Conclusion: QRAGE is a new, successful approach for simultaneously mapping multiple MR parameters at ultrahigh field., (© 2024 The Author(s). Magnetic Resonance in Medicine published by Wiley Periodicals LLC on behalf of International Society for Magnetic Resonance in Medicine.)- Published
- 2024
- Full Text
- View/download PDF
38. Analysis of New Biomarkers for the Study of Schizophrenia Following a Radiomics Approach on MR and PET Imaging.
- Author
-
Carrasco-Poves A, Ruiz-Espana S, Brambilla CR, Neuner I, Rajkumar R, Ramkiran S, Lerche C, and Moratal D
- Subjects
- Bayes Theorem, Biomarkers, Humans, Magnetic Resonance Spectroscopy, Positron-Emission Tomography methods, Schizophrenia diagnostic imaging
- Abstract
Traditionally, the diagnosis of schizophrenia was based on the psychiatrist's introspective diagnosis through clinical stratification factors and score-scales, which led to heterogeneity and discrepancy in the symptoms and results. However, there are many studies trying to improve and assist in how its diagnosis could be performed. To objectively classify schizophrenia patients it is required to determine quantitative biomarkers of the disease. In this contribution we propose a method based on feature extraction both in magnetic resonance (MR) and Positron Emission Tomography (PET) imaging. A dataset of 34 participants (17 patients and 17 control subjects) were analyzed and 5 different brain regions were studied (frontal cortex, posterior cingulate cortex, temporal cortex, primary auditory cortex and thalamus). Following a radiomics approach, 43 texture features were extracted using five different statistical methods. These features were used for the training of the five different predictive models (Linear SVM, Gaussian SVM, Bagged Tree, KNN and Naive Bayes). The precision results were obtained classifying schizophrenia both in MR images (89% Area Under the Curve (AUC) in the posterior cingulate cortex) and with PET images (82% AUC in the frontal cortex), being Linear SVM and Naive Bayes the classification models with the highest predictive power. Clinical Relevance- The current study establishes a methodology to classify schizophrenia disease based on quantitative biomarkers using MR and PET images. This tool could assist the psychiatrist as an additional criterion for the diagnosis evaluation.
- Published
- 2022
- Full Text
- View/download PDF
39. mGluR 5 and GABA A receptor-specific parametric PET atlas construction-PET/MR data processing pipeline, validation, and application.
- Author
-
Kaulen N, Rajkumar R, Régio Brambilla C, Mauler J, Ramkiran S, Orth L, Sbaihat H, Lang M, Wyss C, Rota Kops E, Scheins J, Neumaier B, Ermert J, Herzog H, Langen KJ, Lerche C, Shah NJ, Veselinović T, and Neuner I
- Subjects
- Brain diagnostic imaging, Brain metabolism, Brain Mapping methods, Humans, Magnetic Resonance Imaging, Male, gamma-Aminobutyric Acid metabolism, Positron-Emission Tomography methods, Receptors, GABA-A metabolism
- Abstract
The glutamate and γ-aminobutyric acid neuroreceptor subtypes mGluR
5 and GABAA are hypothesized to be involved in the development of a variety of psychiatric diseases. However, detailed information relating to their in vivo distribution is generally unavailable. Maps of such distributions could potentially aid clinical studies by providing a reference for the normal distribution of neuroreceptors and may also be useful as covariates in advanced functional magnetic resonance imaging (MR) studies. In this study, we propose a comprehensive processing pipeline for the construction of standard space, in vivo distributions of non-displaceable binding potential (BPND ), and total distribution volume (VT ) based on simultaneously acquired bolus-infusion positron emission tomography (PET) and MR data. The pipeline was applied to [11 C]ABP688-PET/MR (13 healthy male non-smokers, 26.6 ± 7.0 years) and [11 C]Flumazenil-PET/MR (10 healthy males, 25.8 ± 3.0 years) data. Activity concentration templates, as well as VT and BPND atlases of mGluR5 and GABAA , were generated from these data. The maps were validated by assessing the percent error δ from warped space to native space in a selection of brain regions. We verified that the average δABP = 3.0 ± 1.0% and δFMZ = 3.8 ± 1.4% were lower than the expected variabilities σ of the tracers (σABP = 4.0%-16.0%, σFMZ = 3.9%-9.5%). An evaluation of PET-to-PET registrations based on the new maps showed higher registration accuracy compared to registrations based on the commonly used [15 O]H2 O-template distributed with SPM12. Thus, we conclude that the resulting maps can be used for further research and the proposed pipeline is a viable tool for the construction of standardized PET data distributions., (© 2022 The Authors. Human Brain Mapping published by Wiley Periodicals LLC.)- Published
- 2022
- Full Text
- View/download PDF
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