38 results on '"Rumpf, Jost‐Julian"'
Search Results
2. No evidence of structural abnormality of the substantia nigra in adult attention-deficit/ hyperactivity disorder: a pilot cross-sectional cohort study.
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Friedrich, Isabel, von Kuenheim, Daniela, Wozniak, David, Meyer, Patrick, Mauche, Nicole, Jue Huang, Classen, Joseph, Strauss, Maria, and Rumpf, Jost-Julian
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ATTENTION-deficit hyperactivity disorder ,SUBSTANTIA nigra ,COHORT analysis ,PARKINSON'S disease ,CROSS-sectional method - Abstract
Background: Abnormal expansion of the echogenic substantia nigra (SN+) is a common observation in Parkinson's disease (PD) and considered a potential trait marker within this context. However, SN+ was also frequently detected in children diagnosed with attention-deficit/hyperactivity disorder (ADHD), where it has been discussed as a biomarker of maturational dopaminergic dysfunction. Interestingly, ADHD was recently linked to an elevated risk of PD in epidemiological studies, particularly among individuals treated with psychostimulants. Here, we investigated the potential of SN echogenicity as a disease biomarker in adults with ADHD and its relation to psychostimulant treatment. Methods: In an exploratory cross-sectional cohort study, we performed transcranial sonography of the SN in 30 adults (mean age 33.3 ± 7.6 years, 19 males/11 females) diagnosed with ADHD according to DSM-V criteria. Results and conclusions: In this pilot study, we observed no evidence of structural abnormalities of the SN among adults diagnosed with ADHD, thus questioning the potential of SN+ as a biomarker for ADHD in this population. Moreover, we found no evidence of treatment-related SN echogenicity changes that would link therapeutic psychostimulant use to alterations in the structural integrity of the SN. [ABSTRACT FROM AUTHOR]
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- 2024
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3. Lateralized effects of post-learning transcranial direct current stimulation on motor memory consolidation in older adults: An fMRI investigation
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King, Bradley R., Rumpf, Jost-Julian, Heise, Kirstin-Friederike, Veldman, Menno P., Peeters, Ronald, Doyon, Julien, Classen, Joseph, Albouy, Genevieve, and Swinnen, Stephan P.
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- 2020
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4. Offline low-frequency rTMS of the primary and premotor cortices does not impact motor sequence memory consolidation despite modulation of corticospinal excitability
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Psurek, Felix, King, Bradley Ross, Classen, Joseph, and Rumpf, Jost-Julian
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- 2021
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5. NFκB Activation by Fas Is Mediated through FADD, Caspase-8, and RIP and Is Inhibited by FLIP
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Kreuz, Sebastian, Siegmund, Daniela, Rumpf, Jost-Julian, Samel, Dierk, Leverkus, Martin, Janssen, Ottmar, Häcker, Georg, Dittrich-Breiholz, Oliver, Kracht, Michael, Scheurich, Peter, and Wajant, Harald
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- 2004
6. Motor learning is independent of effects of subthalamic deep brain stimulation on motor execution
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Muehlberg, Christoph, primary, Fricke, Christopher, additional, Wegscheider, Mirko, additional, Wawrzyniak, Max, additional, Tzvi, Elinor, additional, Winkler, Dirk, additional, Classen, Joseph, additional, and Rumpf, Jost-Julian, additional
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- 2023
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7. Additive value of [18F]PI-2620 perfusion imaging in progressive supranuclear palsy and corticobasal syndrome
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Katzdobler, Sabrina, Nitschmann, Alexander, Nack, Anne, Fietzek, Urban, Kurz, Carolin, Häckert, Jan, Stapf, Theresa, Ferschmann, Christian, Scheifele, Heinrich Maximilian, Eckenweber, Florian, Biechele, Gloria, Franzmeier, Nicolai, Barthel, Henryk, Dewenter, Anna, Schönecker, Sonja, Saur, Dorothee, Schroeter, Matthias L, Rumpf, Jost-Julian, Rullmann, Michael, Schildan, Andreas, Patt, Marianne, Stephens, Andrew W, van Eimeren, Thilo, Bischof, Gerard, Neumaier, Bernd, Drzezga, Alexander, Danek, Adrian, Classen, Joseph, Bürger, Katharina, Janowitz, Daniel, Rauchmann, Boris Stephan, Stöcklein, Sophia, Perneczky, Robert, Schöberl, Florian, Beyer, Leonie, Zwergal, Andreas, Höglinger, Günter U, Bartenstein, Peter, Villemagne, Victor, Seibyl, John, Sabri, Osama, Levin, Johannes, Brendel, Matthias, Tauopathies, German Imaging Initiative for, Marek, Ken, Song, Mengmeng, Wagemann, Olivia, Palleis, Carla, and Weidinger, Endy
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diagnostic imaging [Neurodegenerative Diseases] ,complications [Alzheimer Disease] ,General Medicine ,Middle Aged ,[18F]PI-2620 ,Perfusion ,Neuronal injury ,PET ,Positron-Emission Tomography ,Activities of Daily Living ,Humans ,Radiology, Nuclear Medicine and imaging ,Female ,ddc:610 ,diagnostic imaging [Supranuclear Palsy, Progressive] ,diagnostic imaging [Corticobasal Degeneration] ,Tau ,Aged - Abstract
Purpose Early after [18F]PI-2620 PET tracer administration, perfusion imaging has potential for regional assessment of neuronal injury in neurodegenerative diseases. This is while standard late-phase [18F]PI-2620 tau-PET is able to discriminate the 4-repeat tauopathies progressive supranuclear palsy and corticobasal syndrome (4RTs) from disease controls and healthy controls. Here, we investigated whether early-phase [18F]PI-2620 PET has an additive value for biomarker based evaluation of 4RTs. Methods Seventy-eight patients with 4RTs (71 ± 7 years, 39 female), 79 patients with other neurodegenerative diseases (67 ± 12 years, 35 female) and twelve age-matched controls (69 ± 8 years, 8 female) underwent dynamic (0–60 min) [18F]PI-2620 PET imaging. Regional perfusion (0.5–2.5 min p.i.) and tau load (20–40 min p.i.) were measured in 246 predefined brain regions [standardized-uptake-value ratios (SUVr), cerebellar reference]. Regional SUVr were compared between 4RTs and controls by an ANOVA including false-discovery-rate (FDR, p n = 37), and correlated with clinical severity in 4RTs (PSP rating scale, MoCA, activities of daily living). Results Patients with 4RTs had significant hypoperfusion in 21/246 brain regions, most dominant in thalamus, caudate nucleus, and anterior cingulate cortex, fitting to the topology of the 4RT disease spectrum. However, single region hypoperfusion was not specific regarding the discrimination of patients with 4RTs against patients with other neurodegenerative diseases. In contrast, perfusion pattern expression showed promise for discrimination of patients with 4RTs from other neurodegenerative diseases (AUC: 0.850). Discrimination by the combined perfusion-tau pattern expression (AUC: 0.903) exceeded that of the sole tau pattern expression (AUC: 0.864) and the discriminatory power of the combined perfusion-tau pattern expression was replicated in the external dataset (AUC: 0.917). Perfusion but not tau pattern expression was associated with PSP rating scale (R = 0.402; p = 0.0012) and activities of daily living (R = − 0.431; p = 0.0005). Conclusion [18F]PI-2620 perfusion imaging mirrors known topology of regional hypoperfusion in 4RTs. Single region hypoperfusion is not specific for 4RTs, but perfusion pattern expression may provide an additive value for the discrimination of 4RTs from other neurodegenerative diseases and correlates closer with clinical severity than tau pattern expression.
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- 2023
8. Cross-frequency phase-amplitude coupling in repetitive movements in patients with Parkinson's disease
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Gong, Ruxue, primary, Mühlberg, Christoph, additional, Wegscheider, Mirko, additional, Fricke, Christopher, additional, Rumpf, Jost-Julian, additional, Knösche, Thomas R., additional, and Classen, Joseph, additional
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- 2022
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9. 18F-PI-2620 Tau PET Improves the Imaging Diagnosis of Progressive Supranuclear Palsy
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Messerschmidt, Konstantin, primary, Barthel, Henryk, additional, Brendel, Matthias, additional, Scherlach, Cordula, additional, Hoffmann, Karl-Titus, additional, Rauchmann, Boris-Stephan, additional, Rullmann, Michael, additional, Marek, Kenneth, additional, Villemagne, Victor L., additional, Rumpf, Jost-Julian, additional, Saur, Dorothee, additional, Schroeter, Matthias L., additional, Schildan, Andreas, additional, Patt, Marianne, additional, Beyer, Leonie, additional, Song, Mengmeng, additional, Palleis, Carla, additional, Katzdobler, Sabrina, additional, Fietzek, Urban M., additional, Respondek, Gesine, additional, Scheifele, Maximilian, additional, Nitschmann, Alexander, additional, Zach, Christian, additional, Barret, Olivier, additional, Madonia, Jennifer, additional, Russell, David, additional, Stephens, Andrew W, additional, Koglin, Norman, additional, Roeber, Sigrun, additional, Herms, Jochen, additional, Boetzel, Kai, additional, Bartenstein, Peter, additional, Levin, Johannes, additional, Seibyl, John P., additional, Höglinger, Günter, additional, Classen, Joseph, additional, and Sabri, Osama, additional
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- 2022
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10. Cerebral Activation During Initial Motor Learning Forecasts Subsequent Sleep-Facilitated Memory Consolidation in Older Adults
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King, Bradley R., Saucier, Philippe, Albouy, Genevieve, Fogel, Stuart M., Rumpf, Jost-Julian, Klann, Juliane, Buccino, Giovanni, Binkofski, Ferdinand, Classen, Joseph, Karni, Avi, and Doyon, Julien
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- 2017
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11. 18F-PI-2620 Tau PET Improves the Imaging Diagnosis of Progressive Supranuclear Palsy.
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Messerschmidt, Konstantin, Barthel, Henryk, Brendel, Matthias, Scherlach, Cordula, Hoffmann, Karl-Titus, Rauchmann, Boris-Stephan, Rullmann, Michael, Marek, Kenneth, Villemagne, Victor L., Rumpf, Jost-Julian, Saur, Dorothee, Schroeter, Matthias L., Schildan, Andreas, Patt, Marianne, Beyer, Leonie, Song, Mengmeng, Palleis, Carla, Katzdobler, Sabrina, Fietzek, Urban M., and Respondek, Gesine
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- 2022
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12. Motor Sequence Learning Deficits in Idiopathic Parkinson’s Disease Are Associated With Increased Substantia Nigra Activity
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Tzvi, Elinor, primary, Bey, Richard, additional, Nitschke, Matthias, additional, Brüggemann, Norbert, additional, Classen, Joseph, additional, Münte, Thomas F., additional, Krämer, Ulrike M., additional, and Rumpf, Jost-Julian, additional
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- 2021
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13. Motor Sequence Learning Deficits in Idiopathic Parkinson’s Disease Are Associated With Increased Substantia Nigra Activity
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Tzvi, Elinor, Bey, Richard, Nitschke, Matthias, Brüggemann, Norbert, Classen, Joseph, Münte, Thomas F., Krämer, Ulrike M., and Rumpf, Jost-Julian
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Parkinson’s disease, motor sequence learning, fMRI, dynamic causal modeling, substantia nigra, hippocampus ,ddc:610 - Abstract
Previous studies have shown that persons with Parkinson’s disease (pwPD) share specific deficits in learning new sequential movements, but the neural substrates of this impairment remain unclear. In addition, the degree to which striatal dopaminergic denervation in PD affects the cortico-striato-thalamo-cerebellar motor learning network remains unknown. We aimed to answer these questions using fMRI in 16 pwPD and 16 healthy age-matched control subjects while they performed an implicit motor sequence learning task. While learning was absent in both pwPD and controls assessed with reaction time differences between sequential and random trials, larger error-rates during the latter suggest that at least some of the complex sequence was encoded. Moreover, we found that while healthy controls could improve general task performance indexed by decreased reaction times across both sequence and random blocks, pwPD could not, suggesting disease-specific deficits in learning of stimulus-response associations. Using fMRI, we found that this effect in pwPD was correlated with decreased activity in the hippocampus over time. Importantly, activity in the substantia nigra (SN) and adjacent bilateral midbrain was specifically increased during sequence learning in pwPD compared to healthy controls, and significantly correlated with sequence-specific learning deficits. As increased SN activity was also associated (on trend) with higher doses of dopaminergic medication as well as disease duration, the results suggest that learning deficits in PD are associated with disease progression, indexing an increased drive to recruit dopaminergic neurons in the SN, however, unsuccessfully. Finally, there were no differences between pwPD and controls in task modulation of the cortico-striato-thalamo-cerebellar network. However, a restricted nigral-striatal model showed that negative modulation of SN to putamen connection was larger in pwPD compared to controls during random trials, while no differences between the groups were found during sequence learning. We speculate that learning-specific SN recruitment leads to a relative increase in SN- > putamen connectivity, which returns to a pathological reduced state when no learning takes place
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- 2021
14. sj-pdf-1-jcb-10.1177_0271678X211018904 - Supplemental material for Binding characteristics of [18F]PI-2620 distinguish the clinically predicted tau isoform in different tauopathies by PET
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Song, Mengmeng, Beyer, Leonie, Kaiser, Lena, Barthel, Henryk, van Eimeren, Thilo, Marek, Ken, Nitschmann, Alexander, Scheifele, Maximilian, Palleis, Carla, Respondek, Gesine, Kern, Maike, Biechele, Gloria, Hammes, Jochen, Bischof, Gèrard, Barbe, Michael, Onur, Özgür, Jessen, Frank, Saur, Dorothee, Schroeter, Matthias L, Rumpf, Jost-Julian, Rullmann, Michael, Schildan, Andreas, Patt, Marianne, Neumaier, Bernd, Barret, Olivier, Madonia, Jennifer, Russell, David S, Stephens, Andrew W, Mueller, Andre, Roeber, Sigrun, Herms, Jochen, Bötzel, Kai, Danek, Adrian, Levin, Johannes, Classen, Joseph, Höglinger, Günter U, Bartenstein, Peter, Villemagne, Victor, Drzezga, Alexander, Seibyl, John, Sabri, Osama, Boening, Guido, Ziegler, Sibylle, and Brendel, Matthias
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110320 Radiology and Organ Imaging ,FOS: Clinical medicine ,FOS: Biological sciences ,Medicine ,Cell Biology ,110305 Emergency Medicine ,110306 Endocrinology ,Biochemistry ,69999 Biological Sciences not elsewhere classified ,110904 Neurology and Neuromuscular Diseases ,Neuroscience - Abstract
Supplemental material, sj-pdf-1-jcb-10.1177_0271678X211018904 for Binding characteristics of [18F]PI-2620 distinguish the clinically predicted tau isoform in different tauopathies by PET by Mengmeng Song, Leonie Beyer, Lena Kaiser, Henryk Barthel, Thilo van Eimeren, Ken Marek, Alexander Nitschmann, Maximilian Scheifele, Carla Palleis, Gesine Respondek, Maike Kern, Gloria Biechele, Jochen Hammes, Gèrard Bischof, Michael Barbe, Özgür Onur, Frank Jessen, Dorothee Saur, Matthias L Schroeter, Jost-Julian Rumpf, Michael Rullmann, Andreas Schildan, Marianne Patt, Bernd Neumaier, Olivier Barret, Jennifer Madonia, David S Russell, Andrew W Stephens, Andre Mueller, Sigrun Roeber, Jochen Herms, Kai Bötzel, Adrian Danek, Johannes Levin, Joseph Classen, Günter U Höglinger, Peter Bartenstein, Victor Villemagne, Alexander Drzezga, John Seibyl, Osama Sabri, Guido Boening, Sibylle Ziegler and Matthias Brendel in Journal of Cerebral Blood Flow & Metabolism
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- 2021
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15. Motor Sequence Learning across Multiple Sessions Is Not Facilitated by Targeting Consolidation with Posttraining tDCS in Patients with Progressive Multiple Sclerosis
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Seelmann-Eggebert, Harald, Stoppe, Muriel, Then Bergh, Florian, Classen, Joseph, and Rumpf, Jost-Julian
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Adult ,Male ,Cross-Over Studies ,Article Subject ,Pilot Projects ,Neurosciences. Biological psychiatry. Neuropsychiatry ,Middle Aged ,Multiple Sclerosis, Chronic Progressive ,Transcranial Direct Current Stimulation ,Cross-Sectional Studies ,Double-Blind Method ,Motor Skills ,Humans ,Learning ,Female ,Psychomotor Performance ,Research Article ,Memory Consolidation ,RC321-571 - Abstract
Compared to relapsing-remitting multiple sclerosis (MS), progressive MS is characterized by a lack of spontaneous recovery and a poor response to pharmaceutical immunomodulatory treatment. These patients may, therefore, particularly benefit from interventions that augment training-induced plasticity of the central nervous system. In this cross-sectional double-blind cross-over pilot study, effects of transcranial direct current stimulation (tDCS) on motor sequence learning were examined across four sessions on days 1, 3, 5, and 8 in 16 patients with progressive MS. Active or sham anodal tDCS of the primary motor cortex was applied immediately after each training session. Participants took part in two experiments separated by at least four weeks, which differed with respect to the type of posttraining tDCS (active or sham). While task performance across blocks of training and across sessions improved significantly in both the active and sham tDCS experiment, neither online nor offline motor learning was modulated by the type of tDCS. Accordingly, the primary endpoint (task performance on day 8) did not differ between stimulation conditions. In sum, patients with progressive MS are able to improve performance in an ecologically valid motor sequence learning task through training. However, even multisession posttraining tDCS fails to promote motor learning in progressive MS.
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- 2021
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16. Cross-frequency phase-amplitude coupling in repetitive movements in patients with Parkinson'sdisease.
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Ruxue Gong, Mühlberg, Christoph, Wegscheider, Mirko, Fricke, Christopher, Rumpf, Jost-Julian, Knösche, Thomas R., and Classen, Joseph
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PARKINSON'S disease ,SOMATOSENSORY cortex ,MOVEMENT disorders ,POPULATION dynamics ,HYPOKINESIA - Abstract
Bradykinesia is a cardinal motor symptom in Parkinson's disease (PD), the pathophysiology of which is not fully understood. We analyzed the role of cross-frequency coupling of oscillatory cortical activity in motor impairment in patients with PD and healthy controls. High-density EEG signals were recorded during various motor activities and at rest. Patients performed a repetitive finger-pressing task normally, but were slower than controls during tapping. Phase-amplitude coupling (PAC) between b (13-30 Hz) and broadband c (50-150 Hz) was computed from individual EEG source signals in the premotor, primary motor, and primary somatosensory cortices, and the primary somatosensory complex. In all four regions, averaging the entire movement period resulted in higher PAC in patients than in controls for the resting condition and the pressing task (similar performance between groups). However, this was not the case for the tapping tasks where patients performed slower. This suggests the strength of state-related b-c PAC does not determine Parkinsonian bradykinesia. Examination of the dynamics of oscillatory EEG signals during motor transitions revealed a distinctive motif of PAC rise and decay around press onset. This pattern was also present at press offset and slow tapping onset, linking such idiosyncratic PAC changes to transitions between different movement states. The transition-related PAC modulation in patients was similar to controls in the pressing task but flattened during slow tapping, which related to normal and abnormal performance, respectively. These findings suggest that the dysfunctional evolution of neuronal population dynamics during movement execution is an important component of the pathophysiology of Parkinsonian bradykinesia. NEW & NOTEWORTHY Our findings using noninvasive EEG recordings provide evidence that PAC dynamics might play a role in the physiological cortical control of movement execution and may encode transitions between movement states. Results in patients with Parkinson's disease suggest that bradykinesia is related to a deficit of the dynamic regulation of PAC during movement execution rather than its absolute strength. Our findings may contribute to the development of a new concept of the pathophysiology of bradykinesia. [ABSTRACT FROM AUTHOR]
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- 2022
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17. Binding characteristics of [18F]PI-2620 distinguish the clinically predicted tau isoform in different tauopathies by PET
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Song, Mengmeng, primary, Beyer, Leonie, additional, Kaiser, Lena, additional, Barthel, Henryk, additional, van Eimeren, Thilo, additional, Marek, Ken, additional, Nitschmann, Alexander, additional, Scheifele, Maximilian, additional, Palleis, Carla, additional, Respondek, Gesine, additional, Kern, Maike, additional, Biechele, Gloria, additional, Hammes, Jochen, additional, Bischof, Gèrard, additional, Barbe, Michael, additional, Onur, Özgür, additional, Jessen, Frank, additional, Saur, Dorothee, additional, Schroeter, Matthias L, additional, Rumpf, Jost-Julian, additional, Rullmann, Michael, additional, Schildan, Andreas, additional, Patt, Marianne, additional, Neumaier, Bernd, additional, Barret, Olivier, additional, Madonia, Jennifer, additional, Russell, David S, additional, Stephens, Andrew W, additional, Mueller, Andre, additional, Roeber, Sigrun, additional, Herms, Jochen, additional, Bötzel, Kai, additional, Danek, Adrian, additional, Levin, Johannes, additional, Classen, Joseph, additional, Höglinger, Günter U, additional, Bartenstein, Peter, additional, Villemagne, Victor, additional, Drzezga, Alexander, additional, Seibyl, John, additional, Sabri, Osama, additional, Boening, Guido, additional, Ziegler, Sibylle, additional, and Brendel, Matthias, additional
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- 2021
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18. Microcircuit mechanisms involved in paired associative stimulation-induced depression of corticospinal excitability
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Weise, David, Mann, Jakob, Ridding, Michael, Eskandar, Kevin, Huss, Martin, Rumpf, Jost-Julian, Di Lazzaro, Vincenzo, Mazzone, Paolo, Ranieri, Federico, and Classen, Joseph
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- 2013
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19. Spatiotemporal features of β-γ phase-amplitude coupling in Parkinson’s disease derived from scalp EEG
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Gong, Ruxue, primary, Wegscheider, Mirko, additional, Mühlberg, Christoph, additional, Gast, Richard, additional, Fricke, Christopher, additional, Rumpf, Jost-Julian, additional, Nikulin, Vadim V, additional, Knösche, Thomas R, additional, and Classen, Joseph, additional
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- 2020
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20. Baseline sensorimotor GABA levels shape neuroplastic processes induced by motor learning in older adults
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King, Bradley R., primary, Rumpf, Jost‐Julian, additional, Verbaanderd, Elvire, additional, Heise, Kirstin F., additional, Dolfen, Nina, additional, Sunaert, Stefan, additional, Doyon, Julien, additional, Classen, Joseph, additional, Mantini, Dante, additional, Puts, Nicolaas A. J., additional, Edden, Richard A. E., additional, Albouy, Geneviève, additional, and Swinnen, Stephan P., additional
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- 2020
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21. Binding characteristics of [ 18 F]PI-2620 distinguish the clinically predicted tau isoform in different tauopathies by PET.
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Song, Mengmeng, Beyer, Leonie, Kaiser, Lena, Barthel, Henryk, van Eimeren, Thilo, Marek, Ken, Nitschmann, Alexander, Scheifele, Maximilian, Palleis, Carla, Respondek, Gesine, Kern, Maike, Biechele, Gloria, Hammes, Jochen, Bischof, Gèrard, Barbe, Michael, Onur, Özgür, Jessen, Frank, Saur, Dorothee, Schroeter, Matthias L, and Rumpf, Jost-Julian
- Abstract
The novel tau-PET tracer [
18 F]PI-2620 detects the 3/4-repeat-(R)-tauopathy Alzheimer's disease (AD) and the 4R-tauopathies corticobasal syndrome (CBS) and progressive supranuclear palsy (PSP). We determined whether [18 F]PI-2620 binding characteristics deriving from non-invasive reference tissue modelling differentiate 3/4R- and 4R-tauopathies. Ten patients with a 3/4R tauopathy (AD continuum) and 29 patients with a 4R tauopathy (CBS, PSP) were evaluated. [18 F]PI-2620 PET scans were acquired 0-60 min p.i. and the distribution volume ratio (DVR) was calculated. [18 F]PI-2620-positive clusters (DVR ≥ 2.5 SD vs. 11 healthy controls) were evaluated by non-invasive kinetic modelling. R1 (delivery), k2 & k2a (efflux), DVR, 30-60 min standardized-uptake-value-ratios (SUVR30-60 ) and the linear slope of post-perfusion phase SUVR (9-60 min p.i.) were compared between 3/4R- and 4R-tauopathies. Cortical clusters of 4R-tau cases indicated higher delivery (R1SRTM : 0.92 ± 0.21 vs. 0.83 ± 0.10, p = 0.0007), higher efflux (k2SRTM : 0.17/min ±0.21/min vs. 0.06/min ± 0.07/min, p < 0.0001), lower DVR (1.1 ± 0.1 vs. 1.4 ± 0.2, p < 0.0001), lower SUVR30-60 (1.3 ± 0.2 vs. 1.8 ± 0.3, p < 0.0001) and flatter slopes of the post-perfusion phase (slope9-60 : 0.006/min ± 0.007/min vs. 0.016/min ± 0.008/min, p < 0.0001) when compared to 3/4R-tau cases. [18 F]PI-2620 binding characteristics in cortical regions differentiate 3/4R- and 4R-tauopathies. Higher tracer clearance indicates less stable binding in 4R tauopathies when compared to 3/4R-tauopathies. [ABSTRACT FROM AUTHOR]- Published
- 2021
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22. Dual-Site Transcranial Magnetic Stimulation for the Treatment of Parkinson's Disease
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Fricke, Christopher, Duesmann, Charlotte, Woost, Timo B., von Hofen-Hohloch, Judith, Rumpf, Jost-Julian, Weise, David, and Classen, Joseph
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paired associative stimulation ,coordinated reset ,nervous system ,Neurology ,musculoskeletal, neural, and ocular physiology ,Parkinson's disease ,TMS ,hyperdirect tract ,behavioral disciplines and activities ,Original Research ,dual-site - Abstract
Abnormal oscillatory activity in the subthalamic nucleus (STN) may be relevant for motor symptoms in Parkinson's disease (PD). Apart from deep brain stimulation, transcranial magnetic stimulation (TMS) may be suitable for altering these oscillations. We speculated that TMS to different cortical areas (primary motor cortex, M1, and dorsal premotor cortex, PMd) may activate neuronal subpopulations within the STN via corticofugal neurons projecting directly to the nucleus. We hypothesized that PD symptoms can be ameliorated by a lasting decoupling of STN neurons by associative dual-site repetitive TMS (rTMS). Associative dual-site rTMS (1 Hz) directed to PMd and M1 ("ADS-rTMS") was employed in 20 PD patients treated in a blinded, placebo-controlled cross-over design. Results: No adverse events were noted. We found no significant improvement in clinical outcome parameters (videography of MDS-UPDRS-III, finger tapping, spectral tremor power). Variation of the premotor stimulation site did not induce beneficial effects either. A single session of ADS-rTMS was tolerated well, but did not produce a clinically meaningful benefit on Parkinsonian motor symptoms. Successful treatment using TMS targeting subcortical nuclei may require an intervention over several days or more detailed physiological information about the individual brain state and stimulation-induced subcortical effects.
- Published
- 2019
23. Posttraining Alpha Transcranial Alternating Current Stimulation Impairs Motor Consolidation in Elderly People
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Rumpf, Jost-Julian, Barbu, Alexandru, Fricke, Christopher, Wegscheider, Mirko, and Classen, Joseph
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Male ,Article Subject ,Motor Cortex ,Middle Aged ,Evoked Potentials, Motor ,Transcranial Direct Current Stimulation ,lcsh:RC321-571 ,Double-Blind Method ,Motor Skills ,Humans ,Learning ,Female ,lcsh:Neurosciences. Biological psychiatry. Neuropsychiatry ,Psychomotor Performance ,Research Article ,Aged - Abstract
The retention of a new sequential motor skill relies on repeated practice and subsequent consolidation in the absence of active skill practice. While the early phase of skill acquisition remains relatively unaffected in older adults, posttraining consolidation appears to be selectively impaired by advancing age. Motor learning is associated with posttraining changes of oscillatory alpha and beta neuronal activities in the motor cortex. However, whether or not these oscillatory dynamics relate to posttraining consolidation and how they relate to the age-specific impairment of motor consolidation in older adults remains elusive. Transcranial alternating current stimulation (tACS) is a noninvasive brain stimulation technique capable of modulating such neuronal oscillations. Here, we examined whether tACS targeting M1 immediately following explicit motor sequence training is capable of modulating motor skill consolidation in older adults. In two sets of double-blind, sham-controlled experiments, tACS targeting left M1 was applied at either 10 Hz (alpha-tACS) or 20 Hz (beta-tACS) immediately after termination of a motor sequence training with the right (dominant) hand. Task performance was retested after an interval of 6 hours to assess consolidation of the training-acquired skill. EEG was recorded over left M1 to be able to detect local after-effects on oscillatory activity induced by tACS. Relative to the sham intervention, consolidation was selectively disrupted by posttraining alpha-tACS of M1, while posttraining beta-tACS of M1 had no effect on delayed retest performance compared to the sham intervention. No significant postinterventional changes of oscillatory activity in M1 were detected following alpha-tACS or beta-tACS. Our findings point to a frequency-specific interaction of tACS with posttraining motor memory processing and may suggest an inhibitory role of immediate posttraining alpha oscillations in M1 with respect to motor consolidation in healthy older adults.
- Published
- 2019
24. Interleaving Motor Sequence Training With High-Frequency Repetitive Transcranial Magnetic Stimulation Facilitates Consolidation
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Rumpf, Jost-Julian, primary, May, Luca, primary, Fricke, Christopher, primary, Classen, Joseph, primary, and Hartwigsen, Gesa, primary
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- 2019
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25. Spatiotemporal features of β-γ phase-amplitude coupling in Parkinson's disease derived from scalp EEG.
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Gong, Ruxue, Wegscheider, Mirko, Mühlberg, Christoph, Gast, Richard, Fricke, Christopher, Rumpf, Jost-Julian, Nikulin, Vadim V, Knösche, Thomas R, and Classen, Joseph
- Subjects
PARKINSON'S disease ,INDEPENDENT component analysis ,DOMAIN specificity ,PREMOTOR cortex ,SUBTHALAMIC nucleus ,RESEARCH ,ELECTROENCEPHALOGRAPHY ,NEURAL pathways ,SCALP ,RESEARCH methodology ,MEDICAL cooperation ,EVALUATION research ,COMPARATIVE studies ,SIGNAL processing ,CEREBRAL cortex - Abstract
Abnormal phase-amplitude coupling between β and broadband-γ activities has been identified in recordings from the cortex or scalp of patients with Parkinson's disease. While enhanced phase-amplitude coupling has been proposed as a biomarker of Parkinson's disease, the neuronal mechanisms underlying the abnormal coupling and its relationship to motor impairments in Parkinson's disease remain unclear. To address these issues, we performed an in-depth analysis of high-density EEG recordings at rest in 19 patients with Parkinson's disease and 20 age- and sex-matched healthy control subjects. EEG signals were projected onto the individual cortical surfaces using source reconstruction techniques and separated into spatiotemporal components using independent component analysis. Compared to healthy controls, phase-amplitude coupling of Parkinson's disease patients was enhanced in dorsolateral prefrontal cortex, premotor cortex, primary motor cortex and somatosensory cortex, the difference being statistically significant in the hemisphere contralateral to the clinically more affected side. β and γ signals involved in generating abnormal phase-amplitude coupling were not strictly phase-phase coupled, ruling out that phase-amplitude coupling merely reflects the abnormal activity of a single oscillator in a recurrent network. We found important differences for couplings between the β and γ signals from identical components as opposed to those from different components (originating from distinct spatial locations). While both couplings were abnormally enhanced in patients, only the latter were correlated with clinical motor severity as indexed by part III of the Movement Disorder Society Unified Parkinson's Disease Rating Scale. Correlations with parkinsonian motor symptoms of such inter-component couplings were found in premotor, primary motor and somatosensory cortex, but not in dorsolateral prefrontal cortex, suggesting motor domain specificity. The topography of phase-amplitude coupling demonstrated profound differences in patients compared to controls. These findings suggest, first, that enhanced phase-amplitude coupling in Parkinson's disease patients originates from the coupling between distinct neural networks in several brain regions involved in motor control. Because these regions included the somatosensory cortex, abnormal phase-amplitude coupling is not exclusively tied to the hyperdirect tract connecting cortical regions monosynaptically with the subthalamic nucleus. Second, only the coupling between β and γ signals from different components appears to have pathophysiological significance, suggesting that therapeutic approaches breaking the abnormal lateral coupling between neuronal circuits may be more promising than targeting phase-amplitude coupling per se. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
26. Interleaving Motor Sequence Training With High-Frequency Repetitive Transcranial Magnetic Stimulation Facilitates Consolidation.
- Author
-
Rumpf, Jost-Julian, May, Luca, Fricke, Christopher, Classen, Joseph, and Hartwigsen, Gesa
- Published
- 2020
- Full Text
- View/download PDF
27. Differential Regulation of Human Paired Associative Stimulation-Induced and Theta-Burst Stimulation-Induced Plasticity by L-type and T-type Ca2+Channels
- Author
-
Weise, David, primary, Mann, Jakob, additional, Rumpf, Jost-Julian, additional, Hallermann, Stefan, additional, and Classen, Joseph, additional
- Published
- 2016
- Full Text
- View/download PDF
28. Cerebral Activation During Initial Motor Learning Forecasts Subsequent Sleep-Facilitated Memory Consolidation in Older Adults
- Author
-
King, Bradley R., primary, Saucier, Philippe, additional, Albouy, Genevieve, additional, Fogel, Stuart M., additional, Rumpf, Jost-Julian, additional, Klann, Juliane, additional, Buccino, Giovanni, additional, Binkofski, Ferdinand, additional, Classen, Joseph, additional, Karni, Avi, additional, and Doyon, Julien, additional
- Published
- 2016
- Full Text
- View/download PDF
29. Assessment of Brainstem Function with Auricular Branch of Vagus Nerve Stimulation in Parkinson’s Disease
- Author
-
Weise, David, primary, Adamidis, Melanie, additional, Pizzolato, Fabio, additional, Rumpf, Jost-Julian, additional, Fricke, Christopher, additional, and Classen, Joseph, additional
- Published
- 2015
- Full Text
- View/download PDF
30. A comparison of two surgical approaches in functional neurosurgery: individualized versus conventional stereotactic frames
- Author
-
Matzke, Cornelia, primary, Lindner, Dirk, additional, Schwarz, Johannes, additional, Classen, Joseph, additional, Hammer, Niels, additional, Weise, David, additional, Rumpf, Jost-Julian, additional, Fritzsch, Dominik, additional, Meixensberger, Jürgen, additional, and Winkler, Dirk, additional
- Published
- 2015
- Full Text
- View/download PDF
31. Mechanisms of TRAIL-induced cell signaling
- Author
-
Rumpf, Jost-Julian
- Subjects
Entzündung ,Tumor-Nekrose-Faktor ,Apoptosis ,ddc:610 ,%22">Interferon - Abstract
TRAIL (TNF Related Apoptosis Inducing Ligand), ein Mitglied der TNF-Ligandenfamilie, wurde bislang hauptsächlich hinsichtlich seiner dominanten Funktion als Auslöser des apoptotischen Programms untersucht. In neueren Untersuchungen konnte allerdings gezeigt werden, dass TRAIL unter bestimmten Bedingungen auch eine starke Aktivierung nicht-apoptotischer Signalwege induzieren kann. Um die Mechanismen der TRAIL-induzierten nicht-apoptotischen Signaltransduktion genauer zu untersuchen, wurde in der hier vorliegenden Arbeit besonderes Augenmerk auf die TRAIL-vermittelte Aktivierung des Transkriptionsfaktors NFkB und deren Modulation durch Interferon gamma und FLIP gelegt. Hierbei konnte gezeigt werden, dass Interferon gamma, neben einer synergistischen Wirkung hinsichtlich der TRAIL-induzierten Apoptose, unter nicht-apoptotischen Bedingungen, die durch Caspase-Inhibition oder Bcl2-Überexpression geschaffen wurden, auch eine verstärkende Wirkung auf die TRAIL-induzierten NFkB-Aktivierung in KB-Zellen entfaltet. Weiterhin konnte gezeigt werden, dass FLIP, ein Inhibitor der Caspase-8-Aktivierung, dessen Expression unter anderem durch Interferon gamma reguliert wird, neben einer Apoptose-inhibierenden Wirkung auch die TRAIL-induzierte NFkB-Aktivierung in KB-Zellen inhibiert, was auf eine gemeinsame Regulation beider Mechanismen auf der Ebene des DISC (Death Inducin Signaling Complex) hindeutet., TRAIL (TNF Related Apoptosis Inducing Ligand) is a member of the TNF superfamily and is primarily known for its strong apoptosis inducing capability. However, it could be shown that besides its strong apoptotic potential, TRAIL can also induce non-apoptotic signaling pathways under certain conditions. In this dissertation it is shown that interferon gamma synergistically enhances the TRAIL induced activation of NFkB under non-apoptotic conditions, which were achieved by inhibition of caspases or stable expression of Bcl2 in KB-cells. Furthermore, FLIP, an inhibitor of caspase-8-activation, which is amongst others regulated by interferon gamma, is shown not only to block TRAIL-induced apoptosis but also to inhibit TRAIL-induced NFkB-activation in KB-cells, indicating that both mechanisms are coregulated at the level of the DISC (Death Inducing Signaling Complex).
- Published
- 2007
32. Differential Regulation of Human Paired Associative Stimulation-Induced and Theta-Burst Stimulation-Induced Plasticity by L-type and T-type Ca2+ Channels.
- Author
-
Weise, David, Mann, Jakob, Rumpf, Jost-Julian, Hallermann, Stefan, and Classen, Joseph
- Published
- 2017
- Full Text
- View/download PDF
33. L-Type Voltage-Gated Ca2+ Channels: A Single Molecular Switch for Long-Term Potentiation/Long-Term Depression-Like Plasticity and Activity-Dependent Metaplasticity in Humans.
- Author
-
Wankerl, Katharina, Weise, David, Gentner, Reinhard, Rumpf, Jost-Julian, and Classen, Joseph
- Subjects
SYNAPSES ,DRUG synergism ,MENTAL depression ,TRANSCRANIAL magnetic stimulation ,NIMODIPINE ,PYRAMIDAL tract - Abstract
The ability of synapses to undergo persistent activity-dependent potentiation or depression [long-term potentiation (LTP)/long-term depression (LTD)] may be profoundly altered by previous neuronal activity. Although natural neuronal activity can be experimentally manipulated in vivo, very little is known about the in vivo physiological mechanisms involved in regulating this metaplasticity in models of LTP/LTD. To examine whether Ca
2+ signaling may influence metaplasticity in vivo in humans, we used continuous theta burst stimulation (cTBS) (Huang et al., 2005), a noninvasive novel repetitive magnetic stimulation protocol known to induce persistent alterations of corticospinal excitability whose polarity is changed by previous voluntary motor activity. When directed to the naive motor cortex, cTBS induced long-lasting potentiation of corticospinal excitability, but depression under the influence of nimodipine (NDP), an L-type voltage-gated Ca2+ channel (L-VGCC) antagonist. Both aftereffects were blocked by dextromethorphan, an NMDA receptor antagonist, supporting the notion that these bidirectional cTBS-induced alterations of corticospinal excitability map onto LTP and LTD as observed in animal studies. A short period of voluntary contraction and a small dose of NDP were each ineffective in blocking the cTBS-induced potentiation. However, when both interventions were combined, a depression was induced, and the magnitude of this depression increased with the dose of NDP. These findings suggest that Ca2+ dynamics determine the polarity of LTP/LTD-like changes in vivo. L-VGCCs may act as molecular switches mediating metaplasticity induced by endogenous neuronal activation. [ABSTRACT FROM AUTHOR]- Published
- 2010
- Full Text
- View/download PDF
34. No evidence of structural abnormality of the substantia nigra in adult attention-deficit/hyperactivity disorder: a pilot cross-sectional cohort study.
- Author
-
Friedrich I, von Kuenheim D, Wozniak D, Meyer P, Mauche N, Huang J, Classen J, Strauss M, and Rumpf JJ
- Abstract
Background: Abnormal expansion of the echogenic substantia nigra (SN+) is a common observation in Parkinson's disease (PD) and considered a potential trait marker within this context. However, SN+ was also frequently detected in children diagnosed with attention-deficit/hyperactivity disorder (ADHD), where it has been discussed as a biomarker of maturational dopaminergic dysfunction. Interestingly, ADHD was recently linked to an elevated risk of PD in epidemiological studies, particularly among individuals treated with psychostimulants. Here, we investigated the potential of SN echogenicity as a disease biomarker in adults with ADHD and its relation to psychostimulant treatment., Methods: In an exploratory cross-sectional cohort study, we performed transcranial sonography of the SN in 30 adults (mean age 33.3 ± 7.6 years, 19 males/11 females) diagnosed with ADHD according to DSM-V criteria., Results and Conclusions: In this pilot study, we observed no evidence of structural abnormalities of the SN among adults diagnosed with ADHD, thus questioning the potential of SN+ as a biomarker for ADHD in this population. Moreover, we found no evidence of treatment-related SN echogenicity changes that would link therapeutic psychostimulant use to alterations in the structural integrity of the SN., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Friedrich, von Kuenheim, Wozniak, Meyer, Mauche, Huang, Classen, Strauss and Rumpf.)
- Published
- 2024
- Full Text
- View/download PDF
35. 18 F-PI-2620 Tau PET Improves the Imaging Diagnosis of Progressive Supranuclear Palsy.
- Author
-
Messerschmidt K, Barthel H, Brendel M, Scherlach C, Hoffmann KT, Rauchmann BS, Rullmann M, Marek K, Villemagne VL, Rumpf JJ, Saur D, Schroeter ML, Schildan A, Patt M, Beyer L, Song M, Palleis C, Katzdobler S, Fietzek UM, Respondek G, Scheifele M, Nitschmann A, Zach C, Barret O, Madonia J, Russell D, Stephens AW, Koglin N, Roeber S, Herms J, Bötzel K, Bartenstein P, Levin J, Seibyl JP, Höglinger G, Classen J, and Sabri O
- Subjects
- Humans, tau Proteins, Magnetic Resonance Imaging methods, Atrophy, Supranuclear Palsy, Progressive diagnosis
- Abstract
Progressive supranuclear palsy (PSP) is a 4-repeat tauopathy movement disorder that can be imaged by the
18 F-labeled tau PET tracer 2-(2-([18 F]fluoro)pyridin-4-yl)-9 H -pyrrolo[2,3- b :4,5- c ']dipyridine (18 F-PI-2620). The in vivo diagnosis is currently established on clinical grounds and supported by midbrain atrophy estimation in structural MRI. Here, we investigate whether18 F-PI-2620 tau PET has the potential to improve the imaging diagnosis of PSP. Methods: In this multicenter observational study, dynamic (0-60 min after injection)18 F-PI-2620 PET and structural MRI data for 36 patients with PSP, 22 with PSP-Richardson syndrome, and 14 with a clinical phenotype other than Richardson syndrome (i.e., variant PSP) were analyzed along with data for 10 age-matched healthy controls (HCs). The PET data underwent kinetic modeling, which resulted in distribution volume ratio (DVR) images. These and the MR images were visually assessed by 3 masked experts for typical PSP signs. Furthermore, established midbrain atrophy parameters were measured in structural MR images, and regional DVRs were measured in typical tau-in-PSP target regions in the PET data. Results: Visual assessments discriminated PSP patients and HCs with an accuracy of 63% for MRI and 80% for the combination of MRI and18 F-PI-2620 PET. As compared with patients of the PSP-Richardson syndrome subgroup, those of the variant PSP subgroup profited more in terms of sensitivity from the addition of the visual18 F-PI-2620 PET to the visual MRI information (35% vs. 22%). In quantitative image evaluation, midbrain-to-pons area ratio and globus pallidus DVRs discriminated best between the PSP patients and HCs, with sensitivities and specificities of 83% and 90%, respectively, for MRI and 94% and 100%, respectively, for the combination of MRI and18 F-PI-2620 PET. The gain of sensitivity by adding18 F-PI-2620 PET to MRI data was more marked in clinically less affected patients than in more affected patients (37% vs. 19% for visual, and 16% vs. 12% for quantitative image evaluation). Conclusion: These results provide evidence for an improved imaging-based PSP diagnosis by adding18 F-PI-2620 tau PET to structural MRI. This approach seems to be particularly promising at earlier disease stages and could be of value both for improving early clinical PSP diagnosis and for enriching PSP cohorts for trials of disease-modifying drugs., (© 2022 by the Society of Nuclear Medicine and Molecular Imaging.)- Published
- 2022
- Full Text
- View/download PDF
36. Spatiotemporal features of β-γ phase-amplitude coupling in Parkinson's disease derived from scalp EEG.
- Author
-
Gong R, Wegscheider M, Mühlberg C, Gast R, Fricke C, Rumpf JJ, Nikulin VV, Knösche TR, and Classen J
- Subjects
- Adult, Aged, Electroencephalography methods, Female, Humans, Male, Middle Aged, Neural Pathways physiopathology, Scalp, Signal Processing, Computer-Assisted, Beta Rhythm, Cerebral Cortex physiopathology, Gamma Rhythm, Parkinson Disease physiopathology
- Abstract
Abnormal phase-amplitude coupling between β and broadband-γ activities has been identified in recordings from the cortex or scalp of patients with Parkinson's disease. While enhanced phase-amplitude coupling has been proposed as a biomarker of Parkinson's disease, the neuronal mechanisms underlying the abnormal coupling and its relationship to motor impairments in Parkinson's disease remain unclear. To address these issues, we performed an in-depth analysis of high-density EEG recordings at rest in 19 patients with Parkinson's disease and 20 age- and sex-matched healthy control subjects. EEG signals were projected onto the individual cortical surfaces using source reconstruction techniques and separated into spatiotemporal components using independent component analysis. Compared to healthy controls, phase-amplitude coupling of Parkinson's disease patients was enhanced in dorsolateral prefrontal cortex, premotor cortex, primary motor cortex and somatosensory cortex, the difference being statistically significant in the hemisphere contralateral to the clinically more affected side. β and γ signals involved in generating abnormal phase-amplitude coupling were not strictly phase-phase coupled, ruling out that phase-amplitude coupling merely reflects the abnormal activity of a single oscillator in a recurrent network. We found important differences for couplings between the β and γ signals from identical components as opposed to those from different components (originating from distinct spatial locations). While both couplings were abnormally enhanced in patients, only the latter were correlated with clinical motor severity as indexed by part III of the Movement Disorder Society Unified Parkinson's Disease Rating Scale. Correlations with parkinsonian motor symptoms of such inter-component couplings were found in premotor, primary motor and somatosensory cortex, but not in dorsolateral prefrontal cortex, suggesting motor domain specificity. The topography of phase-amplitude coupling demonstrated profound differences in patients compared to controls. These findings suggest, first, that enhanced phase-amplitude coupling in Parkinson's disease patients originates from the coupling between distinct neural networks in several brain regions involved in motor control. Because these regions included the somatosensory cortex, abnormal phase-amplitude coupling is not exclusively tied to the hyperdirect tract connecting cortical regions monosynaptically with the subthalamic nucleus. Second, only the coupling between β and γ signals from different components appears to have pathophysiological significance, suggesting that therapeutic approaches breaking the abnormal lateral coupling between neuronal circuits may be more promising than targeting phase-amplitude coupling per se., (© The Author(s) (2020). Published by Oxford University Press on behalf of the Guarantors of Brain. All rights reserved. For permissions, please email: journals.permissions@oup.com.)
- Published
- 2021
- Full Text
- View/download PDF
37. Differential Regulation of Human Paired Associative Stimulation-Induced and Theta-Burst Stimulation-Induced Plasticity by L-type and T-type Ca2+ Channels.
- Author
-
Weise D, Mann J, Rumpf JJ, Hallermann S, and Classen J
- Subjects
- Adolescent, Adult, Calcium Channel Blockers pharmacology, Electromyography, Evoked Potentials, Motor drug effects, Evoked Potentials, Motor physiology, Excitatory Amino Acid Antagonists pharmacology, Female, Hand physiology, Humans, Male, Motor Cortex drug effects, Muscle, Skeletal drug effects, Muscle, Skeletal physiology, Neuronal Plasticity drug effects, Pyramidal Tracts drug effects, Pyramidal Tracts metabolism, Receptors, AMPA antagonists & inhibitors, Receptors, AMPA metabolism, Young Adult, Calcium Channels, L-Type metabolism, Calcium Channels, T-Type metabolism, Motor Cortex physiology, Neuronal Plasticity physiology, Transcranial Magnetic Stimulation methods
- Abstract
Activity-dependent changes of postsynaptic Ca2+-concentration are influenced by a variety of different Ca2+-channels and play an important role in synaptic plasticity. Paired associative stimulation (PAS) and theta-burst stimulation (TBS) are noninvasive magnetic stimulation protocols used in human subjects to induce lasting corticospinal excitability changes that have been likened to synaptic long-term potentiation and long-term depression. To better characterize the Ca2+-related physiological mechanisms underlying PAS- and TBS-induced plasticity, we examined the impact of different Ca2+-sources. PAS-induced facilitation of corticospinal excitability was blocked by NMDA-receptor blocker dextromethorphan (DXM) and L-type voltage gated Ca2+ channels (VGCC) blocker nimodipine (NDP), but turned into depression by T-type VGCC blocker ethosuximide (ESM). Although, surprisingly, static corticospinal excitability was increased by the combination of DXM and NDP, PAS-induced facilitation was blocked. TBS-induced facilitation of corticospinal excitability, which has previously been shown to be turned into depression by L-type VGCC blocker NDP (Wankerl K, Weise D, Gentner R, Rumpf J, Classen J. 2010. L-type voltage-gated Ca2+ channels: a single molecular switch for long-term potentiation/long-term depression-like plasticity and activity-dependent metaplasticity in humans. J Neurosci. 30(18):6197-6204.), was blocked, but not reverted, by T-type VGCC blocker ESM. The different patterns of Ca2+-channel modulation of PAS- and TBS-induced plasticity may point to an important role of backpropagating action potentials in PAS-induced plasticity, similar as in spike-timing dependent synaptic plasticity, and to a requirement of dendritic Ca2+-dependent spikes in TBS-induced plasticity., (© The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.)
- Published
- 2017
- Full Text
- View/download PDF
38. L-type voltage-gated Ca2+ channels: a single molecular switch for long-term potentiation/long-term depression-like plasticity and activity-dependent metaplasticity in humans.
- Author
-
Wankerl K, Weise D, Gentner R, Rumpf JJ, and Classen J
- Subjects
- Adult, Calcium Channel Blockers pharmacology, Calcium Channels, L-Type drug effects, Dextromethorphan pharmacology, Dose-Response Relationship, Drug, Drug Interactions, Evoked Potentials, Motor drug effects, Evoked Potentials, Motor physiology, Excitatory Amino Acid Antagonists pharmacology, Female, Humans, Long-Term Potentiation drug effects, Long-Term Synaptic Depression drug effects, Male, Motor Cortex drug effects, Motor Cortex physiology, Muscle Contraction physiology, Neuronal Plasticity drug effects, Nimodipine pharmacology, Pyramidal Tracts drug effects, Pyramidal Tracts physiology, Synaptic Transmission drug effects, Transcranial Magnetic Stimulation, Calcium Channels, L-Type physiology, Long-Term Potentiation physiology, Long-Term Synaptic Depression physiology, Neuronal Plasticity physiology, Synaptic Transmission physiology
- Abstract
The ability of synapses to undergo persistent activity-dependent potentiation or depression [long-term potentiation (LTP)/long-term depression (LTD)] may be profoundly altered by previous neuronal activity. Although natural neuronal activity can be experimentally manipulated in vivo, very little is known about the in vivo physiological mechanisms involved in regulating this metaplasticity in models of LTP/LTD. To examine whether Ca(2+) signaling may influence metaplasticity in vivo in humans, we used continuous theta burst stimulation (cTBS) (Huang et al., 2005), a noninvasive novel repetitive magnetic stimulation protocol known to induce persistent alterations of corticospinal excitability whose polarity is changed by previous voluntary motor activity. When directed to the naive motor cortex, cTBS induced long-lasting potentiation of corticospinal excitability, but depression under the influence of nimodipine (NDP), an L-type voltage-gated Ca(2+) channel (L-VGCC) antagonist. Both aftereffects were blocked by dextromethorphan, an NMDA receptor antagonist, supporting the notion that these bidirectional cTBS-induced alterations of corticospinal excitability map onto LTP and LTD as observed in animal studies. A short period of voluntary contraction and a small dose of NDP were each ineffective in blocking the cTBS-induced potentiation. However, when both interventions were combined, a depression was induced, and the magnitude of this depression increased with the dose of NDP. These findings suggest that Ca(2+) dynamics determine the polarity of LTP/LTD-like changes in vivo. L-VGCCs may act as molecular switches mediating metaplasticity induced by endogenous neuronal activation.
- Published
- 2010
- Full Text
- View/download PDF
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