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Liu C, Liu S, Hu X, Guo Z, Xu Y. Fluctuations in resting motor threshold during electroconvulsive and magnetic seizure therapy. Int J Neurosci 2024:1-12. [PMID: 39230589 DOI: 10.1080/00207454.2024.2401418] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2024] [Revised: 08/31/2024] [Accepted: 09/02/2024] [Indexed: 09/05/2024]
Abstract
OBJECTIVES Magnetic seizure therapy (MST) is more benign than electroconvulsive therapy (ECT) in terms of cognitive impairment. However, whether these two 'artificial seizures' facilitate the central motor neural pathway and the motor cortical effects have not been investigated. The study aimed to compare the effects of ECT and MST on motor-evoked potential (MEP) in patients with mental disorders. METHODS Forty-nine patients with mental disorders (major depressive disorder, bipolar disorder type II and schizophrenia [SCZ]) received 6 treatment sessions of vertex MST versus 6 bifrontal ECT treatments in a nonrandomized comparative clinical design. Data on the duration of motor seizures were collected for each treatment. MEP latency and the resting motor threshold (rMT) were measured at baseline and after every two treatments. Comparisons were performed between or within the groups. RESULTS Seizure durations were significantly longer in the ECT group compared to the MST group across multiple sessions. Both MST and ECT demonstrated a significant reduction in rMT in the left and right hemispheres after the fourth (T3) and sixth treatments (T4) compared to baseline (T1). However, there were no significant changes in MEP latency within or between the groups throughout the treatment sessions. The only difference was that the rMT in the left cerebral hemisphere was significantly lower after T4 than after the second treatment (T2). There was no difference in rMT between the ECT and MST groups. CONCLUSIONS Both ECT and MST facilitate the central motor pathway, with a shared mechanism of increased motor cortex excitability.
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Affiliation(s)
- Chaojie Liu
- Department of Psychiatry, The First Hospital of Shanxi Medical University, Taiyuan, Shanxi, China
- First Clinical Medical College, Shanxi Medical University, Taiyuan, Shanxi, China
- Department of Anaesthesiology, Shanxi Province Cancer Hospital (Shanxi Hospital Affiliated to Cancer Hospital, Chinese Academy of Medical Science, Cancer Hospital Affiliated to Shanxi Medical University), Taiyuan, Shanxi, China
| | - Sha Liu
- Department of Psychiatry, The First Hospital of Shanxi Medical University, Taiyuan, Shanxi, China
- Shanxi Key Laboratory of Artificial Intelligence Assisted Diagnosis and Treatment for Mental Disorder, Taiyuan, Shanxi, China
| | - Xiaodong Hu
- Department of Psychiatry, The First Hospital of Shanxi Medical University, Taiyuan, Shanxi, China
| | - Zhenglong Guo
- Department of Psychiatry, The First Hospital of Shanxi Medical University, Taiyuan, Shanxi, China
- First Clinical Medical College, Shanxi Medical University, Taiyuan, Shanxi, China
| | - Yong Xu
- Department of Psychiatry, The First Hospital of Shanxi Medical University, Taiyuan, Shanxi, China
- First Clinical Medical College, Shanxi Medical University, Taiyuan, Shanxi, China
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Helling RM, Shmuely S, Bauer PR, Tolner EA, Visser GH, Thijs RD. Tracking cortical excitability dynamics with transcranial magnetic stimulation in focal epilepsy. Ann Clin Transl Neurol 2022; 9:540-551. [PMID: 35297209 PMCID: PMC8994988 DOI: 10.1002/acn3.51535] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2021] [Revised: 02/21/2022] [Accepted: 02/23/2022] [Indexed: 11/05/2022] Open
Abstract
INTRODUCTION The lack of reliable biomarkers constrain epilepsy management. We assessed the potential of repeated transcranial magnetic stimulation with electromyography (TMS-EMG) to track dynamical changes in cortical excitability on a within-subject basis. METHODS We recruited people with refractory focal epilepsy who underwent video-EEG monitoring and drug tapering as part of the presurgical evaluation. We performed daily TMS-EMG measurements with additional postictal assessments 1-6 h following seizures to assess resting motor threshold (rMT), and motor evoked potentials (MEPs) with single- and paired-pulse protocols. Anti-seizure medication (ASM) regimens were recorded for the day before each measurement and expressed in proportion to the dosage before tapering. Additional measurements were performed in healthy controls to evaluate day-to-day rMT variability. RESULTS We performed 77 (58 baseline, 19 postictal) measurements in 16 people with focal epilepsy and 35 in seven healthy controls. Controls showed minimal day-to-day rMT variation. Withdrawal of ASMs was associated with a lower rMT without affecting MEPs of single- and paired-pulse TMS-EMG paradigms. Postictal measurements following focal to bilateral tonic-clonic seizures demonstrated unaltered rMT and increased short interval intracortical inhibition, while measurements following focal seizures with impaired awareness showed decreased rMT's and reduced short and long interval intracortical inhibition. CONCLUSION Serial within-subject rMT measurements yielded reproducible, stable results in healthy controls. ASM tapering and seizures had distinct effects on TMS-EMG excitability indices in people with epilepsy. Drug tapering decreased rMT, indicating increased overall corticospinal excitability, whereas seizures affected intracortical inhibition with contrasting effects between seizure types.
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Affiliation(s)
- Robert M Helling
- Stichting Epilepsie Instellingen Nederland (SEIN), Heemstede, The Netherlands
| | - Sharon Shmuely
- Stichting Epilepsie Instellingen Nederland (SEIN), Heemstede, The Netherlands.,NIHR University College London Hospitals Biomedical Research Centre, UCL Institute of Neurology, Queen Square, London, UK
| | - Prisca R Bauer
- Department of Psychosomatic Medicine and Psychotherapy, University Medical Center Freiburg, Germany
| | - Else A Tolner
- Department of Neurology, Leiden University Medical Centre, Leiden, The Netherlands.,Department of Human Genetics, Leiden University Medical Centre, Leiden, The Netherlands
| | - Gerhard H Visser
- Stichting Epilepsie Instellingen Nederland (SEIN), Heemstede, The Netherlands
| | - Roland D Thijs
- Stichting Epilepsie Instellingen Nederland (SEIN), Heemstede, The Netherlands.,NIHR University College London Hospitals Biomedical Research Centre, UCL Institute of Neurology, Queen Square, London, UK.,Department of Neurology, Leiden University Medical Centre, Leiden, The Netherlands
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Tsuboyama M, Liu J, Kaye H, DiBacco M, Pearl PL, Rotenberg A. Transcranial Magnetic Stimulation in Succinic Semialdehyde Dehydrogenase Deficiency: A Measure of Maturational Trajectory of Cortical Excitability. J Child Neurol 2021; 36:1169-1176. [PMID: 34058900 PMCID: PMC8630082 DOI: 10.1177/08830738211008735] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
BACKGROUND Succinic semialdehyde dehydrogenase deficiency (SSADHD) is a disorder of GABA degradation with use-dependent downregulation of postsynaptic GABAA/B receptors. We aim to measure the resulting cortical excitation: inhibition ratio using transcranial magnetic stimulation. METHODS In this single-center observational study, 18 subjects with SSADHD and 8 healthy controls underwent transcranial magnetic stimulation. Resting motor threshold, cortical silent period, and long-interval intracortical inhibition were measured in both groups. Resting motor threshold in focal epilepsy patients from an institutional transcranial magnetic stimulation database were also included. RESULTS SSADHD subjects had higher resting motor threshold than healthy controls but lower relative to focal epilepsy patients. Resting motor threshold decreased with age in all groups. Cortical silent period was longer in SSADHD subjects than in healthy controls. No difference was detected in long-interval intracortical inhibition between the 2 groups. CONCLUSION Findings suggest abnormal corticospinal tract physiology in SSADHD, but with preserved developmental trajectory for corticospinal tract maturation. Defining features of these transcranial magnetic stimulation metrics in SSADHD will be better elucidated through this ongoing longitudinal study.
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Affiliation(s)
- Melissa Tsuboyama
- Division of Epilepsy and Clinical Neurophysiology, Department of Neurology, 1862Boston Children's Hospital, Boston, MA, USA
| | - Jingjing Liu
- Division of Epilepsy and Clinical Neurophysiology, Department of Neurology, 1862Boston Children's Hospital, Boston, MA, USA.,F.M. Kirby Neurobiology Center, 1862Boston Children's Hospital, Boston, MA, USA
| | - Harper Kaye
- 12259Boston University School of Medicine, Behavioral Neuroscience Program, Boston, MA, USA
| | - Melissa DiBacco
- Division of Epilepsy and Clinical Neurophysiology, Department of Neurology, 1862Boston Children's Hospital, Boston, MA, USA
| | - Phillip L Pearl
- Division of Epilepsy and Clinical Neurophysiology, Department of Neurology, 1862Boston Children's Hospital, Boston, MA, USA
| | - Alexander Rotenberg
- Division of Epilepsy and Clinical Neurophysiology, Department of Neurology, 1862Boston Children's Hospital, Boston, MA, USA.,F.M. Kirby Neurobiology Center, 1862Boston Children's Hospital, Boston, MA, USA.,Berenson-Allen Center for Noninvasive Brain Stimulation, Department of Neurology, Beth Israel Deaconess Medical Center, Boston, MA, USA
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Antidepressant effect of repetitive transcranial magnetic stimulation is not impaired by intake of lithium or antiepileptic drugs. Eur Arch Psychiatry Clin Neurosci 2021; 271:1245-1253. [PMID: 34218305 PMCID: PMC8429361 DOI: 10.1007/s00406-021-01287-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/04/2021] [Accepted: 06/21/2021] [Indexed: 12/29/2022]
Abstract
INTRODUCTION The effect of concomitant medication on repetitive transcranial magnetic stimulation (rTMS) outcomes in depression remains understudied. Recent analyses show attenuation of rTMS effects by antipsychotic medication and benzodiazepines, but data on the effects of antiepileptic drugs and lithium used as mood stabilizers or augmenting agents are sparse despite clinical relevance. Preclinical electrophysiological studies suggest relevant impact of the medication on treatment, but this might not translate into clinical practice. We aimed to investigate the role of lithium (Li), lamotrigine (LTG) and valproic acid (VPA) by analyzing rTMS treatment outcomes in depressed patients. METHODS 299 patients with uni- and bipolar depression treated with rTMS were selected for analysis in respect to intake of lithium, lamotrigine and valproic acid. The majority (n = 251) were treated with high-frequency (10-20 Hz) rTMS of the lDLPFC for an average of 17 treatment sessions with a figure-of-8 coil with a MagVenture system aiming for 110% resting motor threshold, and smaller groups of patients were being treated with other protocols including intermittent theta-burst stimulation and bilateral prefrontal and medial prefrontal protocols. For group comparisons, we used analysis of variance with the between-subjects factor group or Chi-Square Test of Independence depending on the scales of measurement. For post-hoc tests, we used least significant difference (LSD). For differences in treatment effects between groups, we used an ANOVA with the between-subjects factor group (groups: no mood stabilizer, Li, LTG, VPA, Li + LTG) the within-subjects factor treatment (pre vs. post treatment with rTMS) and also Chi-Square Tests of independence for response and remission. RESULTS Overall, patients showed an amelioration of symptoms with no significant differences for the main effect of group and for the interaction effect treatment by group. Based on direct comparisons between the single groups taking mood stabilizers against the group taking no mood stabilizers, we see a superior effect of lamotrigine, valproic acid and combination of lithium and lamotrigine for the response and remission rates. Motor threshold was significantly and markedly higher for patients taking valproic acid. CONCLUSION Being treated with lithium, lamotrigine and valproic acid had no relevant influence on rTMS treatment outcome. The results suggest there is no reason for clinicians to withhold or withdraw these types of medication from patients who are about to undergo a course of rTMS. Prospective controlled work on the subject is encouraged.
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Badran BW, Caulfield KA, Cox C, Lopez JW, Borckardt JJ, DeVries WH, Summers P, Kerns S, Hanlon CA, McTeague LM, George MS, Roberts DR. Brain stimulation in zero gravity: transcranial magnetic stimulation (TMS) motor threshold decreases during zero gravity induced by parabolic flight. NPJ Microgravity 2020; 6:26. [PMID: 33024819 PMCID: PMC7505837 DOI: 10.1038/s41526-020-00116-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2020] [Accepted: 08/14/2020] [Indexed: 01/09/2023] Open
Abstract
We are just beginning to understand how spaceflight may impact brain function. As NASA proceeds with plans to send astronauts to the Moon and commercial space travel interest increases, it is critical to understand how the human brain and peripheral nervous system respond to zero gravity. Here, we developed and refined head-worn transcranial magnetic stimulation (TMS) systems capable of reliably and quickly determining the amount of electromagnetism each individual needs to detect electromyographic (EMG) threshold levels in the thumb (called the resting motor threshold (rMT)). We then collected rMTs in 10 healthy adult participants in the laboratory at baseline, and subsequently at three time points onboard an airplane: (T1) pre-flight at Earth gravity, (T2) during zero gravity periods induced by parabolic flight and (T3) post-flight at Earth gravity. Overall, the subjects required 12.6% less electromagnetism applied to the brain to cause thumb muscle activation during weightlessness compared to Earth gravity, suggesting neurophysiological changes occur during brief periods of zero gravity. We discuss several candidate explanations for this finding, including upward shift of the brain within the skull, acute increases in cortical excitability, changes in intracranial pressure, and diffuse spinal or neuromuscular system effects. All of these possible explanations warrant further study. In summary, we documented neurophysiological changes during brief episodes of zero gravity and thus highlighting the need for further studies of human brain function in altered gravity conditions to optimally prepare for prolonged microgravity exposure during spaceflight.
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Affiliation(s)
- Bashar W Badran
- Brain Stimulation Division, Department of Psychiatry & Behavioral Sciences, Medical University of South Carolina, Charleston, SC 29425 USA
| | - Kevin A Caulfield
- Brain Stimulation Division, Department of Psychiatry & Behavioral Sciences, Medical University of South Carolina, Charleston, SC 29425 USA
| | - Claire Cox
- Brain Stimulation Division, Department of Psychiatry & Behavioral Sciences, Medical University of South Carolina, Charleston, SC 29425 USA
| | - James W Lopez
- Brain Stimulation Division, Department of Psychiatry & Behavioral Sciences, Medical University of South Carolina, Charleston, SC 29425 USA
| | - Jeffrey J Borckardt
- Brain Stimulation Division, Department of Psychiatry & Behavioral Sciences, Medical University of South Carolina, Charleston, SC 29425 USA.,Ralph H. Johnson VA Medical Center, Charleston, SC 29401 USA.,Department of Anesthesia and Perioperative Medicine, Medical University of South Carolina, Charleston, SC 29425 USA
| | - William H DeVries
- Brain Stimulation Division, Department of Psychiatry & Behavioral Sciences, Medical University of South Carolina, Charleston, SC 29425 USA
| | - Philipp Summers
- Brain Stimulation Division, Department of Psychiatry & Behavioral Sciences, Medical University of South Carolina, Charleston, SC 29425 USA
| | - Suzanne Kerns
- Brain Stimulation Division, Department of Psychiatry & Behavioral Sciences, Medical University of South Carolina, Charleston, SC 29425 USA
| | - Colleen A Hanlon
- Brain Stimulation Division, Department of Psychiatry & Behavioral Sciences, Medical University of South Carolina, Charleston, SC 29425 USA
| | - Lisa M McTeague
- Brain Stimulation Division, Department of Psychiatry & Behavioral Sciences, Medical University of South Carolina, Charleston, SC 29425 USA.,Ralph H. Johnson VA Medical Center, Charleston, SC 29401 USA
| | - Mark S George
- Brain Stimulation Division, Department of Psychiatry & Behavioral Sciences, Medical University of South Carolina, Charleston, SC 29425 USA.,Ralph H. Johnson VA Medical Center, Charleston, SC 29401 USA
| | - Donna R Roberts
- Department of Radiology, Medical University of South Carolina, Charleston, SC 29425 USA
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Tsuboyama M, Kaye HL, Rotenberg A. Review of Transcranial Magnetic Stimulation in Epilepsy. Clin Ther 2020; 42:1155-1168. [PMID: 32624320 DOI: 10.1016/j.clinthera.2020.05.016] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2019] [Revised: 05/18/2020] [Accepted: 05/27/2020] [Indexed: 12/25/2022]
Abstract
PURPOSE Despite the availability of numerous pharmacologic and nonpharmacologic antiseizure therapies, a fraction of patients with epilepsy remain refractory to current treatment options, underscoring the need for novel drugs and neuromodulatory therapies. Transcranial magnetic stimulation (TMS), coupled with either electromyography or electroencephalography, enables rapid measurement of the cortical excitation/inhibition ratio, which is pathologically shifted toward excess excitability in patients with epilepsy. In this review, we summarize: (1) TMS protocols that have been deployed to identify promising compounds in the antiepilepsy drug (AED)-development pipeline, and (2) the therapeutic potential of TMS in the treatment of drug-resistant seizures. METHODS A focused literature review of the use of TMS in epilepsy, using a PubMed search, was performed. Over 70 articles were included that pertained to: (1) the use of TMS-EMG and TMS-EEG in elucidating the mechanisms of action of AEDs and in discovering potential new AEDs; and (2) the use of repetitive TMS in the treatment of seizures. FINDINGS Studies from the literature have reported that AEDs alter TMS-derived metrics, typically by leading to a net increase in cortical inhibition with successful therapy. Preclinical TMS work in rodent models of epilepsy has led to the development of novel antiseizure drug compounds. Clinical translational studies of TMS have been used to determine guidelines on the dosages of other agents in the AED pipeline in preparation for clinical trials. Several studies have described the use of therapeutic repetitive TMS in both the ictal and interictal states of epilepsy, with inconsistent results. IMPLICATIONS TMS has diagnostic and therapeutic potential in epilepsy. TMS-derived markers can enable early-stage measures of AED target engagement, and can facilitate studies of the pharmacokinetic and pharmacodynamic properties of AEDs. TMS may also be used in the early prediction of the efficacy of different AEDs in treating patients, and in direct neuromodulation of epileptic networks. From the therapeutics perspective, despite favorable results in some trials, the optimization of treatment paradigms and the determination of ideal candidates for TMS are still needed. Finally, preclinical experiments of TMS have provided mechanistic insight into its effects on the excitation/inhibition ratio, and may facilitate rational drug-device coupling paradigms. Overall, the capacity of TMS in both the modulation and measurement of changes in cortical excitability highlights its unique role in advancing antiepilepsy therapeutics.
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Affiliation(s)
- Melissa Tsuboyama
- Neuromodulation Program, Department of Neurology, Division of Epilepsy and Clinical Neurophysiology, Boston Children's Hospital, Boston, MA, USA; FM Kirby Neurobiology Center, Department of Neurology, Boston Children's Hospital, Boston, MA, USA
| | - Harper L Kaye
- Behavioral Neuroscience Program, Boston University School of Medicine, Boston, MA, USA
| | - Alexander Rotenberg
- Neuromodulation Program, Department of Neurology, Division of Epilepsy and Clinical Neurophysiology, Boston Children's Hospital, Boston, MA, USA; FM Kirby Neurobiology Center, Department of Neurology, Boston Children's Hospital, Boston, MA, USA; Berenson-Allen Center for Noninvasive Brain Stimulation, Beth Israel Deaconess Medical Center, Boston, MA, USA.
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Tsuboyama M, Lee Kaye H, Rotenberg A. Biomarkers Obtained by Transcranial Magnetic Stimulation of the Motor Cortex in Epilepsy. Front Integr Neurosci 2019; 13:57. [PMID: 31736722 PMCID: PMC6837164 DOI: 10.3389/fnint.2019.00057] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2019] [Accepted: 09/23/2019] [Indexed: 12/13/2022] Open
Abstract
Epilepsy is associated with numerous neurodevelopmental disorders. Transcranial magnetic stimulation (TMS) of the motor cortex coupled with electromyography (EMG) enables biomarkers that provide measures of cortical excitation and inhibition that are particularly relevant to epilepsy and related disorders. The motor threshold (MT), cortical silent period (CSP), short interval intracortical inhibition (SICI), intracortical facilitation (ICF), and long interval intracortical inhibition (LICI) are among TMS-derived metrics that are modulated by antiepileptic drugs. TMS may have a practical role in optimization of antiepileptic medication regimens, as studies demonstrate dose-dependent relationships between TMS metrics and acute medication administration. A close association between seizure freedom and normalization of cortical excitability with long-term antiepileptic drug use highlights a plausible utility of TMS in measures of anti-epileptic drug efficacy. Finally, TMS-derived biomarkers distinguish patients with various epilepsies from healthy controls and thus may enable development of disorder-specific biomarkers and therapies both within and outside of the epilepsy realm.
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Affiliation(s)
- Melissa Tsuboyama
- Neuromodulation Program, Department of Neurology, Division of Epilepsy and Clinical Neurophysiology, Boston Children's Hospital, Boston, MA, United States.,FM Kirby Neurobiology Center, Department of Neurology, Boston Children's Hospital, Boston, MA, United States
| | - Harper Lee Kaye
- Neuromodulation Program, Department of Neurology, Division of Epilepsy and Clinical Neurophysiology, Boston Children's Hospital, Boston, MA, United States.,FM Kirby Neurobiology Center, Department of Neurology, Boston Children's Hospital, Boston, MA, United States
| | - Alexander Rotenberg
- Neuromodulation Program, Department of Neurology, Division of Epilepsy and Clinical Neurophysiology, Boston Children's Hospital, Boston, MA, United States.,FM Kirby Neurobiology Center, Department of Neurology, Boston Children's Hospital, Boston, MA, United States.,Berenson-Allen Center for Noninvasive Brain Stimulation, Beth Israel Deaconess Medical Center, Boston, MA, United States
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Minzenberg MJ, Leuchter AF. The effect of psychotropic drugs on cortical excitability and plasticity measured with transcranial magnetic stimulation: Implications for psychiatric treatment. J Affect Disord 2019; 253:126-140. [PMID: 31035213 DOI: 10.1016/j.jad.2019.04.067] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/08/2018] [Revised: 03/03/2019] [Accepted: 04/08/2019] [Indexed: 01/08/2023]
Abstract
OBJECTIVE Repetitive transcranial magnetic stimulation (rTMS) is an emerging treatment for neuropsychiatric disorders. Patients in rTMS treatment typically receive concomitant psychotropic medications, which affect neuronal excitability and plasticity and may interact to affect rTMS treatment outcomes. A greater understanding of these drug effects may have considerable implications for optimizing multi-modal treatment of psychiatric patients, and elucidating the mechanism(s) of action (MOA) of rTMS. METHOD We summarized the empirical literature that tests how psychotropic drugs affect cortical excitability and plasticity, using varied experimental TMS paradigms. RESULTS Glutamate antagonists robustly attenuate plasticity, largely without changes in excitability per se; antiepileptic drugs show the opposite pattern of effects, while calcium channel blockers attenuate plasticity. Benzodiazepines have moderate and variable effects on plasticity, and negligible effects on excitability. Antidepressants with potent 5HT transporter inhibition reduce both excitability and alter plasticity, while antidepressants with other MOAs generally lack either effect. Catecholaminergic drugs, cholinergic agents and lithium have minimal effects on excitability but exhibit robust and complex, non-linear effects in TMS plasticity paradigms. LIMITATIONS These effects remain largely untested in sustained treatment protocols, nor in clinical populations. In addition, how these medications impact clinical response to rTMS remains largely unknown. CONCLUSIONS Psychotropic medications exert robust and varied effects on cortical excitability and plasticity. We encourage the field to more directly and fully investigate clinical pharmaco-TMS studies to improve outcomes.
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Affiliation(s)
- M J Minzenberg
- Neuromodulation Division, Department of Psychiatry, Semel Institute for Neuroscience and Human Behavior, University of California, 760 Westwood Plaza, Los Angeles, CA 90024, United States.
| | - A F Leuchter
- Neuromodulation Division, Department of Psychiatry, Semel Institute for Neuroscience and Human Behavior, University of California, 760 Westwood Plaza, Los Angeles, CA 90024, United States
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Martinotti G, Montemitro C, Pettorruso M, Viceconte D, Alessi MC, Di Carlo F, Lucidi L, Picutti E, Santacroce R, Di Giannantonio M. Augmenting pharmacotherapy with neuromodulation techniques for the treatment of bipolar disorder: a focus on the effects of mood stabilizers on cortical excitability. Expert Opin Pharmacother 2019; 20:1575-1588. [PMID: 31150304 DOI: 10.1080/14656566.2019.1622092] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Introduction: Mood stabilizers and antipsychotics have been demonstrated to be effective in Bipolar Disorder, with lithium as the gold standard. However, the presence of adverse events and treatment-resistance is still a relevant issue. To this respect, the use of brain stimulation techniques may be considered as an augmentation strategy, with both Transcranial Magnetic Stimulation (TMS) and Transcranial Direct Current Stimulation (tDCS) having shown some level of efficacy in bipolar patients although clinical trials are still not sufficient to draw any conclusion. Areas covered: The authors have conducted a systematic review of the literature, in order to evaluate the role of mood stabilizers on neural activity and cortical excitability. Furthermore, the article reviews neuromodulation techniques and highlights the potential of integrating pharmacological first-line therapies with these techniques to treat BD patients. Expert opinion: The combination of neuromodulation techniques and available pharmacotherapies is a valuable opportunity which is not undermined by specific effects on cortical excitability and could improve BD patient outcome. Neurostimulation techniques may be considered safer than antidepressant treatments in BD, with a lower level of manic switches and may represent a new treatment strategy in BD depressive episodes.
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Affiliation(s)
- G Martinotti
- Department of Neuroscience, Imaging and Clinical Sciences, University "G. d'Annunzio" of Chieti , Chieti , Italy.,Department of Pharmacy, Pharmacology, Clinical Science, University of Hertfordshire , Herts , UK
| | - C Montemitro
- Department of Neuroscience, Imaging and Clinical Sciences, University "G. d'Annunzio" of Chieti , Chieti , Italy
| | - M Pettorruso
- Department of Neuroscience, Imaging and Clinical Sciences, University "G. d'Annunzio" of Chieti , Chieti , Italy
| | - D Viceconte
- Department of Neuroscience, Imaging and Clinical Sciences, University "G. d'Annunzio" of Chieti , Chieti , Italy
| | - M C Alessi
- Department of Neuroscience, Imaging and Clinical Sciences, University "G. d'Annunzio" of Chieti , Chieti , Italy
| | - F Di Carlo
- Department of Neuroscience, Imaging and Clinical Sciences, University "G. d'Annunzio" of Chieti , Chieti , Italy
| | - L Lucidi
- Department of Neuroscience, Imaging and Clinical Sciences, University "G. d'Annunzio" of Chieti , Chieti , Italy
| | - E Picutti
- Department of Neuroscience, Imaging and Clinical Sciences, University "G. d'Annunzio" of Chieti , Chieti , Italy
| | - R Santacroce
- Department of Neuroscience, Imaging and Clinical Sciences, University "G. d'Annunzio" of Chieti , Chieti , Italy
| | - M Di Giannantonio
- Department of Neuroscience, Imaging and Clinical Sciences, University "G. d'Annunzio" of Chieti , Chieti , Italy
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Li X, Sahlem GL, Badran BW, McTeague LM, Hanlon CA, Hartwell KJ, Henderson S, George MS. Transcranial magnetic stimulation of the dorsal lateral prefrontal cortex inhibits medial orbitofrontal activity in smokers. Am J Addict 2017; 26:788-794. [PMID: 28898485 DOI: 10.1111/ajad.12621] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2017] [Revised: 08/14/2017] [Accepted: 08/17/2017] [Indexed: 11/28/2022] Open
Abstract
BACKGROUND AND OBJECTIVE Several studies have shown that repetitive transcranial magnetic stimulation (rTMS), applied to the dorsolateral prefrontal cortex (DLPFC), can reduce cue-elicited craving in smokers. Currently, the mechanism of this effect is unknown. We used functional magnetic resonance imaging (fMRI) to explore the effect of a single treatment of rTMS on cortical and sub-cortical neural activity in non-treatment seeking nicotine-dependent participants. METHODS We conducted a randomized, counterbalanced, crossover trial in which participants attended two experimental visits separated by at least 1 week. On the first visit, participants received either active, or sham rTMS (10 Hz, 5 s-on, 10 s-off, 100% motor threshold, 3,000 pulses) over the left DLPFC, and on the second visit they received the opposite condition (active or sham). Cue craving fMRI scans were completed before and after each rTMS session. RESULTS A total of 11 non-treatment seeking nicotine-dependent cigarette smokers were enrolled in the study [six female, average age 39.7 ± 13.2, average cigarettes per day 17.3 ± 5.9]. Active rTMS decreased activity in the contralateral medial orbitofrontal cortex (mOFC) and ipsilateral nucleus accumbens (NAc) compared to sham rTMS. CONCLUSIONS This preliminary data suggests that one session of rTMS applied to the DLPFC decreases brain activity in the NAc and mOFC in smokers. SCIENTIFIC SIGNIFICANCE rTMS may exert its anti-craving effect by decreasing activity in the NAc and mOFC in smokers. Despite a small sample size, these findings warrant future rTMS/fMRI studies in addictions. (Am J Addict 2017;26:788-794).
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Affiliation(s)
- Xingbao Li
- Brain Stimulation Division, Department of Psychiatry, Medical University of South Carolina, Charleston, South Carolina.,Center for Biomedical Imaging, Medical University of South Carolina, Charleston, South Carolina
| | - Gregory L Sahlem
- Brain Stimulation Division, Department of Psychiatry, Medical University of South Carolina, Charleston, South Carolina
| | - Bashar W Badran
- Brain Stimulation Division, Department of Psychiatry, Medical University of South Carolina, Charleston, South Carolina
| | - Lisa M McTeague
- Brain Stimulation Division, Department of Psychiatry, Medical University of South Carolina, Charleston, South Carolina
| | - Colleen A Hanlon
- Brain Stimulation Division, Department of Psychiatry, Medical University of South Carolina, Charleston, South Carolina.,Center for Biomedical Imaging, Medical University of South Carolina, Charleston, South Carolina
| | - Karen J Hartwell
- Brain Stimulation Division, Department of Psychiatry, Medical University of South Carolina, Charleston, South Carolina
| | - Scott Henderson
- Brain Stimulation Division, Department of Psychiatry, Medical University of South Carolina, Charleston, South Carolina
| | - Mark S George
- Brain Stimulation Division, Department of Psychiatry, Medical University of South Carolina, Charleston, South Carolina.,Center for Biomedical Imaging, Medical University of South Carolina, Charleston, South Carolina.,Ralph H. Johnson VA Medical Center, Charleston, South Carolina
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11
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Li X, Du L, Sahlem GL, Badran BW, Henderson S, George MS. Repetitive transcranial magnetic stimulation (rTMS) of the dorsolateral prefrontal cortex reduces resting-state insula activity and modulates functional connectivity of the orbitofrontal cortex in cigarette smokers. Drug Alcohol Depend 2017; 174:98-105. [PMID: 28319755 PMCID: PMC5400684 DOI: 10.1016/j.drugalcdep.2017.02.002] [Citation(s) in RCA: 57] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/17/2016] [Revised: 12/01/2016] [Accepted: 02/21/2017] [Indexed: 01/19/2023]
Abstract
BACKGROUND Previous studies reported that repetitive transcranial magnetic stimulation (rTMS) can reduce cue-elicited craving and decrease cigarette consumption in smokers. The mechanism of this effect however, remains unclear. We used resting-state functional magnetic resonance imaging (rsfMRI) to test the effect of rTMS in non-treatment seeking smokers. METHODS We used a single blinded, sham-controlled, randomized counterbalanced crossover design where participants underwent two visits separated by at least 1 week. Participants received active rTMS over the left dorsolateral prefrontal cortex (DLPFC) during one of their visits, and sham rTMS during their other visit. They had two rsFMRI scans before and after each rTMS session. We used the same rTMS stimulation parameters as in a previous study (10Hz, 5s-on, 10s-off, 100% resting motor threshold, 3000 pulses). RESULTS Ten non-treatment-seeking, nicotine-dependent, cigarette smokers (6 women, an average age of 39.72 and an average cigarette per day of 17.30) finished the study. rsFMRI results demonstrate that as compared to a single session of sham rTMS, a single session of active rTMS inhibits brain activity in the right insula and thalamus in fractional amplitude of low frequency fluctuation (fALFF). For intrinsic brain connectivity comparisons, active TMS resulted in significantly decreased connectivity from the site of rTMS to the left orbitomedial prefrontal cortex. CONCLUSIONS This data suggests that one session of rTMS can reduce activity in the right insula and right thalamus as measured by fALFF. The data also demonstrates that rTMS can reduce rsFC between the left DLPFC and the medial orbitofrontal cortex.
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Affiliation(s)
- Xingbao Li
- Brain Stimulation Division, Department of Psychiatry, Medical University of South Carolina, Charleston, SC, 29425, USA; Center for Biomedical Imaging, Medical University of South Carolina, Charleston, SC, 29425, USA.
| | - Lian Du
- Brain Stimulation Division, Department of Psychiatry, Medical University of South Carolina, Charleston, SC, 29425, USA,Department of Psychiatry, Chongqing Medical University, Chongqing, China
| | - Gregory L. Sahlem
- Brain Stimulation Division, Department of Psychiatry, Medical University of South Carolina, Charleston, SC, 29425, USA
| | - Bashar W. Badran
- Brain Stimulation Division, Department of Psychiatry, Medical University of South Carolina, Charleston, SC, 29425, USA
| | - Scott Henderson
- Brain Stimulation Division, Department of Psychiatry, Medical University of South Carolina, Charleston, SC, 29425, USA
| | - Mark S. George
- Brain Stimulation Division, Department of Psychiatry, Medical University of South Carolina, Charleston, SC, 29425, USA,Center for Biomedical Imaging, Medical University of South Carolina, Charleston, SC, 29425, USA,Ralph H. Johnson VA Medical Center, Charleston, SC, 29425, USA
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12
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ter Braack EM, Koopman AWE, van Putten MJ. Early TMS evoked potentials in epilepsy: A pilot study. Clin Neurophysiol 2016; 127:3025-3032. [DOI: 10.1016/j.clinph.2016.06.003] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2014] [Revised: 05/31/2016] [Accepted: 06/03/2016] [Indexed: 11/16/2022]
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13
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Hanlon CA, DeVries W, Dowdle LT, West JA, Siekman B, Li X, George MS. A comprehensive study of sensorimotor cortex excitability in chronic cocaine users: Integrating TMS and functional MRI data. Drug Alcohol Depend 2015; 157:28-35. [PMID: 26541870 PMCID: PMC4899825 DOI: 10.1016/j.drugalcdep.2015.07.1196] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/18/2015] [Revised: 06/23/2015] [Accepted: 07/09/2015] [Indexed: 10/23/2022]
Abstract
BACKGROUND Disruptions in motor control are often overlooked features of chronic cocaine users. During a simple sensorimotor integration task, for example, cocaine users activate a larger area of cortex than controls but have lower functional connectivity between the cortex and dorsal striatum, which is further correlated with poor performance. The purpose of this study was to determine whether abnormal cortical excitability in cocaine users was related to disrupted inhibitory or excitatory mechanisms, as measured by transcranial magnetic stimulation (TMS). METHODS A battery of TMS measures were acquired from 87 individuals (50 cocaine dependent, 37 controls). Functional MRI data were acquired from a subset of 28 individuals who performed a block-design finger tapping task. RESULTS TMS measures revealed that cocaine users had significantly higher resting motor thresholds and higher intracortical cortical facilitation (ICF) than controls. There was no between-group difference in either measure of cortical inhibition. Task-evoked BOLD signal in the motor cortex was significantly correlated with ICF in the cocaine users. There was no significant difference in brain-skull distance between groups. CONCLUSION These data demonstrated that cocaine users have disrupted cortical facilitation (as measured with TMS), which is related to elevated BOLD signal. Cortical inhibition, however, is largely intact. Given the relationship between ICF and glutamatergic agents, this may be a potentially fruitful and treatable target in addiction. Finally, among controls the distance from the scalp to the cortex was correlated with the motor threshold which may be a useful parameter to integrate into therapeutic TMS protocols in the future.
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Affiliation(s)
- Colleen A. Hanlon
- Department of Psychiatry and Behavioral Sciences, Medical University of South Carolina, Charleston, SC, United States,Corresponding author at: Departments of Psychiatry and Neurosciences, Medical University of South Carolina, Charleston, SC, United States. (C.A. Hanlon)
| | - William DeVries
- Department of Psychiatry and Behavioral Sciences, Medical University of South Carolina, Charleston, SC, United States
| | - Logan T. Dowdle
- Department of Psychiatry and Behavioral Sciences, Medical University of South Carolina, Charleston, SC, United States,Ralph H.Johnson VA Medical Center, Charleston, SC, United States
| | - Julia A. West
- Department of Psychiatry and Behavioral Sciences, Medical University of South Carolina, Charleston, SC, United States,Ralph H.Johnson VA Medical Center, Charleston, SC, United States
| | - Bradley Siekman
- Department of Psychiatry and Behavioral Sciences, Medical University of South Carolina, Charleston, SC, United States,Ralph H.Johnson VA Medical Center, Charleston, SC, United States
| | - Xingbao Li
- Department of Psychiatry and Behavioral Sciences, Medical University of South Carolina, Charleston, SC, United States
| | - Mark S. George
- Department of Psychiatry and Behavioral Sciences, Medical University of South Carolina, Charleston, SC, United States,Ralph H.Johnson VA Medical Center, Charleston, SC, United States
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14
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Pallanti S, Grassi G, Antonini S, Quercioli L, Salvadori E, Hollander E. rTMS in resistant mixed states: an exploratory study. J Affect Disord 2014; 157:66-71. [PMID: 24581830 DOI: 10.1016/j.jad.2013.12.024] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/28/2013] [Revised: 12/12/2013] [Accepted: 12/13/2013] [Indexed: 01/21/2023]
Abstract
BACKGROUND Repetitive transcranial magnetic stimulation (rTMS) has shown efficacy in resistant unipolar depression, but its efficacy in bipolar disorders has not yet been extensively investigated. Mixed episodes are reported in up to 40% of acute bipolar admissions and are associated with severe psychopathology, comorbidity, high risk of suicide and poor treatment response. Right low-frequency rTMS (LF-rTMS) as an augmentation treatment might be effective for mixed states. METHODS Forty patients were treated during a 4-week period with a mood stabilizer and subsequent rTMS (low frequency stimulation - 1Hz - applied to the right Dorso-Lateral Prefrontal Cortex (DLPFC)) as add-on treatment for 3 weeks. Response to LF-rTMS was assessed by the Hamilton Depression Rating Scale (HAM-D), the Young Mania Rating Scale (YMRS) and the Clinical Global Impressions-Bipolar Version (CGIBP) subscales. ANOVA with repeated measures performed on HAM-D, YMRS and CGI-BP subscales "change from the preceding phase" and "severity of illness" showed a statistically significant time effect from the baseline to the endpoint. RESULTS For the HAM-D there was a 46.6% responder rate, of which 28.6% was remitted, while for the YMRS there was a 15% responder rate, all of which was remitted. LIMITATIONS The open label-design of our study and the lack of a sham-controlled group represent a methodological limitation. CONCLUSIONS The results suggest that LF-rTMS on the right DLFC might be a potential augmentation strategy in the treatment of both depressive and manic symptoms in mixed states.
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Affiliation(s)
- Stefano Pallanti
- Department of Psychiatry and Behavioral Medicine, University of California, Davis, USA; Department of Neurofarba, University of Florence, Via delle Gore 2H, 50100 Florence, Italy; Institute of Neuroscience, Florence, Italy; Deprtament of Psychiatry, Icahn School of Medicine, NY, USA.
| | - Giacomo Grassi
- Department of Neurofarba, University of Florence, Via delle Gore 2H, 50100 Florence, Italy
| | | | | | - Emilia Salvadori
- Department of Neurofarba, University of Florence, Via delle Gore 2H, 50100 Florence, Italy
| | - Eric Hollander
- Department of Psychiatry and Behavioral Sciences, Albert Einstein College of Medicine, NY, USA
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15
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BAUER PRISCAR, KALITZIN STILIYAN, ZIJLMANS MAEIKE, SANDER JOSEMIRW, VISSER GERHARDH. CORTICAL EXCITABILITY AS A POTENTIAL CLINICAL MARKER OF EPILEPSY: A REVIEW OF THE CLINICAL APPLICATION OF TRANSCRANIAL MAGNETIC STIMULATION. Int J Neural Syst 2014; 24:1430001. [DOI: 10.1142/s0129065714300010] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Transcranial magnetic stimulation (TMS) can be used for safe, noninvasive probing of cortical excitability (CE). We review 50 studies that measured CE in people with epilepsy. Most showed cortical hyperexcitability, which can be corrected with anti-epileptic drug treatment. Several studies showed that decrease of CE after epilepsy surgery is predictive of good seizure outcome. CE is a potential biomarker for epilepsy. Clinical application may include outcome prediction of drug treatment and epilepsy surgery.
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Affiliation(s)
- PRISCA R. BAUER
- SEIN - Epilepsy Institute in the Netherlands Foundation, Heemstede, The Netherlands, P.O. Box 540, 2130 AM Hoofddorp, The Netherlands
| | - STILIYAN KALITZIN
- SEIN - Epilepsy Institute in the Netherlands Foundation, Heemstede, The Netherlands, P.O. Box 540, 2130 AM Hoofddorp, The Netherlands
| | - MAEIKE ZIJLMANS
- SEIN - Epilepsy Institute in the Netherlands Foundation, Heemstede, The Netherlands, P.O. Box 540, 2130 AM Hoofddorp, The Netherlands
- Department of Neurology, Brain Center Rudolf Magnus, University Medical Centre Utrecht, Utrecht, The Netherlands
| | - JOSEMIR W. SANDER
- SEIN - Epilepsy Institute in the Netherlands Foundation, Heemstede, The Netherlands, P.O. Box 540, 2130 AM Hoofddorp, The Netherlands
- NIHR University College London Hospitals Biomedical Research Centre, UCL Institute of Neurology, Queen Square, London WC1N 3BG, United Kingdom
- Epilepsy Society, Chalfont St Peter, SL9 0RJ, United Kingdom
| | - GERHARD H. VISSER
- SEIN - Epilepsy Institute in the Netherlands Foundation, Heemstede, The Netherlands, P.O. Box 540, 2130 AM Hoofddorp, The Netherlands
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16
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Danner N, Julkunen P, Hyppönen J, Niskanen E, Säisänen L, Könönen M, Koskenkorva P, Vanninen R, Kälviäinen R, Mervaala E. Alterations of motor cortical excitability and anatomy in Unverricht-Lundborg disease. Mov Disord 2013; 28:1860-7. [DOI: 10.1002/mds.25615] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2012] [Revised: 06/08/2013] [Accepted: 06/25/2013] [Indexed: 11/09/2022] Open
Affiliation(s)
- Nils Danner
- Institute of Clinical Medicine, School of Medicine, Faculty of Health Sciences; University of Eastern Finland; Kuopio Finland
- Department of Clinical Neurophysiology; Kuopio University Hospital; Kuopio Finland
| | - Petro Julkunen
- Department of Clinical Neurophysiology; Kuopio University Hospital; Kuopio Finland
| | - Jelena Hyppönen
- Department of Clinical Neurophysiology; Kuopio University Hospital; Kuopio Finland
| | - Eini Niskanen
- Department of Clinical Radiology; Kuopio University Hospital; Kuopio Finland
- Department of Applied Physics; University of Eastern Finland; Kuopio Finland
| | - Laura Säisänen
- Institute of Clinical Medicine, School of Medicine, Faculty of Health Sciences; University of Eastern Finland; Kuopio Finland
- Department of Clinical Neurophysiology; Kuopio University Hospital; Kuopio Finland
| | - Mervi Könönen
- Department of Clinical Neurophysiology; Kuopio University Hospital; Kuopio Finland
- Department of Clinical Radiology; Kuopio University Hospital; Kuopio Finland
| | - Päivi Koskenkorva
- Department of Clinical Radiology; Kuopio University Hospital; Kuopio Finland
| | - Ritva Vanninen
- Institute of Clinical Medicine, School of Medicine, Faculty of Health Sciences; University of Eastern Finland; Kuopio Finland
- Department of Clinical Radiology; Kuopio University Hospital; Kuopio Finland
| | - Reetta Kälviäinen
- Institute of Clinical Medicine, School of Medicine, Faculty of Health Sciences; University of Eastern Finland; Kuopio Finland
- Department of Neurology; Kuopio University Hospital; Kuopio Finland
| | - Esa Mervaala
- Institute of Clinical Medicine, School of Medicine, Faculty of Health Sciences; University of Eastern Finland; Kuopio Finland
- Department of Clinical Neurophysiology; Kuopio University Hospital; Kuopio Finland
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17
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Bauer PR, Vansteensel MJ, Bleichner MG, Hermes D, Ferrier CH, Aarnoutse EJ, Ramsey NF. Mismatch Between Electrocortical Stimulation and Electrocorticography Frequency Mapping of Language. Brain Stimul 2013; 6:524-31. [DOI: 10.1016/j.brs.2013.01.001] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2012] [Revised: 12/06/2012] [Accepted: 01/02/2013] [Indexed: 11/28/2022] Open
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Vitikainen AM, Salli E, Lioumis P, Mäkelä JP, Metsähonkala L. Applicability of nTMS in locating the motor cortical representation areas in patients with epilepsy. Acta Neurochir (Wien) 2013; 155:507-18. [PMID: 23328919 DOI: 10.1007/s00701-012-1609-5] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2012] [Accepted: 12/27/2012] [Indexed: 11/26/2022]
Abstract
BACKGROUND Transcranial magnetic stimulation (TMS) is increasingly used for non-invasive functional mapping in preoperative evaluation for brain surgery, and the reliability of navigated TMS (nTMS) motor representation maps has been studied in the healthy population and in brain tumor patients. The lesions behind intractable epilepsy differ from typical brain tumors, ranging from developmental cortical malformations to injuries early in development, and may influence the functional organization of the cortical areas. Moreover, the interictal cortical epileptic activity and antiepileptic medication may affect the nTMS motor threshold. The reliability of the nTMS motor representation localization in epilepsy patients has not been addressed. METHODS We compared the nTMS motor cortical representation maps of hand and arm muscles with the results of invasive electrical cortical stimulation (ECS) in 13 patients with focal epilepsy. The nTMS maps were projected to the cortical surface segmented from preoperative magnetic resonance images (MRI), and the positions of the subdural electrodes were extracted from the postoperative low-dose computed tomography (CT) images registered with preoperative MRI. RESULTS The 3D distance between the average nTMS site and average ECS electrode location was 11 ± 4 mm for the hand and 16 ± 7 mm for arm muscle representation areas. In all patients the representation areas defined with nTMS and ECS were located on the same gyrus, also in patients with abundant interictal epileptic activity on the motor gyrus. CONCLUSIONS nTMS can reliably locate the hand motor cortical representation area with the accuracy needed for pre-surgical evaluation in patients with epilepsy.
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MESH Headings
- Adolescent
- Adult
- Arm/innervation
- Brain Mapping/methods
- Brain Neoplasms/physiopathology
- Brain Neoplasms/surgery
- Child
- Electric Stimulation
- Electromyography
- Epilepsies, Partial/physiopathology
- Epilepsies, Partial/surgery
- Epilepsy, Frontal Lobe/physiopathology
- Epilepsy, Frontal Lobe/surgery
- Epilepsy, Partial, Motor/physiopathology
- Epilepsy, Partial, Motor/surgery
- Hand/innervation
- Humans
- Image Interpretation, Computer-Assisted/methods
- Imaging, Three-Dimensional
- Magnetic Resonance Imaging/methods
- Male
- Motor Cortex/physiopathology
- Muscle, Skeletal/innervation
- Preoperative Care/methods
- Retrospective Studies
- Somatosensory Cortex/physiopathology
- Tomography, X-Ray Computed/methods
- Transcranial Magnetic Stimulation/methods
- Young Adult
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Affiliation(s)
- Anne-Mari Vitikainen
- Department of Radiology, HUS Medical Imaging Center, Helsinki University Central Hospital and University of Helsinki, P.O. Box 340, 00029, Helsinki, Finland.
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19
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Delvendahl I, Lindemann H, Heidegger T, Normann C, Ziemann U, Mall V. Effects of lamotrigine on human motor cortex plasticity. Clin Neurophysiol 2012; 124:148-53. [PMID: 22750085 DOI: 10.1016/j.clinph.2012.05.011] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2012] [Revised: 05/08/2012] [Accepted: 05/16/2012] [Indexed: 01/20/2023]
Abstract
OBJECTIVE Besides its use in epilepsy, lamotrigine (LTG) is also effective as mood stabilizer. The pathophysiology of mood disorders may incorporate a dysfunction of neuronal plasticity and animal experiments suggest that mood stabilizers influence induction of long-term potentiation (LTP) and -depression (LTD), two major forms of synaptic plasticity. However, the exact modes of action of LTG and its impact on neuronal plasticity in humans remain unclear. METHODS Here, we tested the effects of a single oral dose of LTG (300 mg) on motor cortical plasticity induced by paired associative stimulation (PAS(25)), a protocol that typically induces LTP-like plasticity, in 26 young healthy adults in a placebo-controlled, randomized, double-blind crossover design. We stratified analysis of the LTG effects according to the individual PAS(25) response in the placebo session (14 LTP-responders vs. 12 LTD-responders). Plasticity was indexed by motor evoked potential (MEP) amplitudes recorded before and for 60 min after PAS(25). RESULTS LTG resulted in a significant reduction of the LTP-like MEP increase in the LTP-responders and a reduction of the LTD-like MEP decrease in the LTD-responders, with the majority of LTD-responders even showing an MEP increase. CONCLUSIONS In summary, LTG differentially modulated cortical plasticity induced by non-invasive brain stimulation in human subjects depending on their individual intrinsic propensity for expressing LTP-like or LTD-like plasticity. SIGNIFICANCE Findings contribute to our understanding of the anticonvulsant and antidepressant clinical effects of LTG, which have been suggested to occur, at least in part, through downregulation of LTP (epilepsy) and LTD (depressive disorders).
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Affiliation(s)
- Igor Delvendahl
- European Neuroscience Institute Göttingen, Göttingen, Germany
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20
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Ellis LD, Soanes KH. A larval zebrafish model of bipolar disorder as a screening platform for neuro-therapeutics. Behav Brain Res 2012; 233:450-7. [PMID: 22677277 DOI: 10.1016/j.bbr.2012.05.043] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2012] [Revised: 05/24/2012] [Accepted: 05/25/2012] [Indexed: 11/18/2022]
Abstract
Modelling neurological diseases has proven extraordinarily difficult due to the phenotypic complexity of each disorder. The zebrafish has become a useful model system with which to study abnormal neurological and behavioural activity and holds promise as a model of human disease. While most of the disease modelling using zebrafish has made use of adults, larvae hold tremendous promise for the high-throughput screening of potential therapeutics. The further development of larval disease models will strengthen their ability to contribute to the drug screening process. Here we have used zebrafish larvae to model the symptoms of bipolar disorder by treating larvae with sub-convulsive concentrations of the GABA antagonist pentylenetetrazol (PTZ). A number of therapeutics that act on different targets, in addition to those that have been used to treat bipolar disorder, were tested against this model to assess its predictive value. Carbamazepine, valproic acid, baclofen and honokiol, were found to oppose various aspects of the PTZ-induced changes in activity. Lidocaine and haloperidol exacerbated the PTZ-induced activity changes and sulpiride had no effect. By comparing the degree of phenotypic rescue with the mechanism of action of each therapeutic we have shown that the low-concentration PTZ model can produce a number of intermediate phenotypes that model symptoms of bipolar disorder, may be useful in modelling other disease states, and will help predict the efficacy of novel therapeutics.
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Affiliation(s)
- Lee David Ellis
- National Research Council of Canada, Aquatic and Crop Resource Development, 1411 Oxford Street, Halifax, Nova Scotia B3H 3Z1, Canada
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21
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Ellis LD, Seibert J, Soanes KH. Distinct models of induced hyperactivity in zebrafish larvae. Brain Res 2012; 1449:46-59. [PMID: 22386495 DOI: 10.1016/j.brainres.2012.02.022] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2011] [Revised: 02/01/2012] [Accepted: 02/09/2012] [Indexed: 11/30/2022]
Abstract
The analysis of behavioural hyperactivity can provide insights into how perturbations in normal activity may be linked to the altered function of the nervous system and possibly the symptoms of disease. As a small vertebrate zebrafish have numerous experimental advantages that are making them a powerful model for these types of studies. While the majority of behavioural studies have focused on adult zebrafish, it has become apparent that larvae can also display complex stereotypical patterns of behaviour. Here we have used three compounds (pentylenetetrazole (PTZ), aconitine and 4-aminopyridine) that have different neuronal targets (GABA, sodium and potassium channels), to induce distinct patterns of hyperactivity in larvae. Our studies have revealed that each compound produces a number of distinct concentration-dependent activity patterns. This work has shown for the first time that at sub-convulsive concentrations, PTZ can reverse the normal behavioural response to alternating periods of light and dark in zebrafish larvae. It also appears that both PTZ and 4-aminopyridine produce distinct changes in the normal startle response patterns immediately following light/dark transitions that may be the result of an elevation in stress/anxiety. Aconitine produces a general elevation in activity that eliminates the normal response to light and dark. In addition to differences in the patterns of behaviour each compound also produces a unique pattern of c-fos (an immediate early gene) expression in the brain. While more work is required to make direct links between region specific neuronal activity and individual behaviours, these models provide a framework with which to study and compare mechanistically different types of inducible behaviours.
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Affiliation(s)
- Lee David Ellis
- Institute for Marine Biosciences Room 325A, National Research Council of Canada, Institute for Marine Biosciences., 1411 Oxford Street,Halifax, Nova Scotia, Canada B3H 3Z1
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22
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Li X, Large CH, Ricci R, Taylor JJ, Nahas Z, Bohning DE, Morgan P, George MS. Using interleaved transcranial magnetic stimulation/functional magnetic resonance imaging (fMRI) and dynamic causal modeling to understand the discrete circuit specific changes of medications: lamotrigine and valproic acid changes in motor or prefrontal effective connectivity. Psychiatry Res 2011; 194:141-8. [PMID: 21924874 DOI: 10.1016/j.pscychresns.2011.04.012] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/25/2010] [Revised: 04/27/2011] [Accepted: 04/28/2011] [Indexed: 10/17/2022]
Abstract
The purpose of this study was to use interleaved transcranial magnetic stimulation/functional magnetic resonance imaging (TMS/fMRI) to investigate the effects of lamotrigine (LTG) and valproic acid (VPA) on effective connectivity within motor and corticolimbic circuits. In this randomized, double-blind, crossover trial, 30 healthy volunteers received either drug or placebo 3.5 h prior to interleaved TMS/fMRI. We utilized dynamic causal modeling (DCM) to assess changes in the endogenous effective connectivity of bidirectional networks in the motor-sensory system and corticolimbic circuit. Results indicate that both LTG and VPA have network-specific effects. When TMS was applied over the motor cortex, both LTG and VPA reduced TMS-specific effective connectivity between primary motor (M1) and pre-motor cortex (PMd), and between M1 and the supplementary area motor (SMA). When TMS was applied over prefrontal cortex, however, LTG alone increased TMS-specific effective connectivity between the left dorsolateral prefrontal cortex(DLPFC) and the anterior cingulate cortex (ACC). In summary, LTG and VPA inhibited effective connectivity in motor circuits, but LTG alone increased effective connectivity in prefrontal circuits. These results suggest that interleaved TMS/fMRI can assess region- and circuit-specific effects of medications or interventions.
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Affiliation(s)
- Xingbao Li
- Department of Psychiatry, Medical University of South Carolina, Charleston, SC, USA.
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23
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Re: Modulation of human motor cortex excitability by valproate. Psychopharmacology (Berl) 2011; 216:145-6. [PMID: 21336578 DOI: 10.1007/s00213-011-2195-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/05/2011] [Accepted: 01/17/2011] [Indexed: 10/18/2022]
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Zunhammer M, Langguth B, Landgrebe M, Frank E, Müller S, Burger J, Sand PG, Eichhammer P, Hajak G. Modulation of human motor cortex excitability by valproate. Psychopharmacology (Berl) 2011; 215:277-80. [PMID: 21161183 DOI: 10.1007/s00213-010-2126-y] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/07/2010] [Accepted: 12/01/2010] [Indexed: 11/26/2022]
Abstract
RATIONALE Valproate is widely used in the treatment of epilepsy, bipolar disorder, and chronic pain disorders, but its exact mechanisms of action is still incompletely understood. OBJECTIVES Here we used transcranial magnetic stimulation to explore effects of a single dose of 800 mg valproate on motor cortex excitability in healthy volunteers. METHODS Motor threshold, peripheral maximum M-wave, cortical silent period short intracortical inhibition, intracortical facilitation, and motor evoked potential recruitment were assessed before and 1.5 h after the administration of valproate in 15 (eight male, seven female) healthy volunteers. RESULTS None of the measures of cortical excitability were found to be altered significantly after valproate. CONCLUSION These results are in line with previous findings of unaffected intracortical excitability after a single dose of valproate, suggesting that valproate's immediate in vivo actions do not resemble the effects of classic GABAergic compounds.
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Affiliation(s)
- Matthias Zunhammer
- Department of Psychiatry, Psychotherapy and Psychosomatics, University of Regensburg, Universitaetsstraße 84, 93053 Regensburg, Germany
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George MS. Transcranial magnetic stimulation for the treatment of depression. Expert Rev Neurother 2011; 10:1761-72. [PMID: 20977332 DOI: 10.1586/ern.10.95] [Citation(s) in RCA: 66] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Repeated daily left prefrontal transcranial magnetic stimulation (TMS) was first proposed as a potential treatment for depression in 1993. Multiple studies from researchers around the world since then have repeatedly demonstrated that TMS has antidepressant effects greater than sham treatment, and that these effects are clinically meaningful. A large industry-sponsored trial, published in 2007, resulted in US FDA approval in October 2008. Most recently, a large NIH-sponsored trial, with a more rigorous sham technique, found that a course of treatment (3-5 weeks) was statistically and clinically significant in reducing depression. However, consistently showing statistically and clinically significant antidepressant effects, and gaining regulatory approval, is merely the beginning for this new treatment. As with any new treatment involving a radically different approach, there are many unanswered questions about TMS, and the field is still rapidly evolving. These unanswered questions include the appropriate scalp location, understanding the mechanisms of action, refining the 'dose' (frequency, train, number of stimuli/day and pattern of delivery), understanding whether and how TMS can be combined with medications or talking/exposure therapy, or both, and how to deliver maintenance TMS. This article summarizes the available clinical information, and discusses key areas where more research is needed. TMS reflects a paradigm shift in treating depression. It is a safe, relatively noninvasive, focal brain stimulation treatment that does not involve seizures or implanted wires, and does not have drug-drug interactions or systemic side effects.
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Affiliation(s)
- Mark S George
- Institute of Psychiatry, Medical University of South Carolina, 502 N, 67 President St, Charleston, SC 29425, USA.
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Bogdanov VB, Multon S, Chauvel V, Bogdanova OV, Prodanov D, Makarchuk MY, Schoenen J. Migraine preventive drugs differentially affect cortical spreading depression in rat. Neurobiol Dis 2010; 41:430-5. [PMID: 20977938 DOI: 10.1016/j.nbd.2010.10.014] [Citation(s) in RCA: 84] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2010] [Revised: 10/10/2010] [Accepted: 10/15/2010] [Indexed: 10/18/2022] Open
Abstract
Cortical spreading depression (CSD) is the most likely cause of the migraine aura. Drugs with distinct pharmacological properties are effective in the preventive treatment of migraine. To test the hypothesis that their common denominator might be suppression of CSD we studied in rats the effect of three drugs used in migraine prevention: lamotrigine which is selectively effective on the aura but not on the headache, valproate and riboflavin which have a non-selective effect. Rats received for 4 weeks daily intraperitoneal injections of one of the three drugs. For valproate and riboflavin we used saline as control, for lamotrigine its vehicle dimethyl sulfoxide. After treatment, cortical spreading depressions were elicited for 2h by occipital KCl application. We measured CSD frequency, its propagation between a posterior (parieto-occipital) and an anterior (frontal) electrode, and number of Fos-immunoreactive nuclei in frontal cortex. Lamotrigine suppressed CSDs by 37% and 60% at posterior and anterior electrodes. Valproate had no effect on posterior CSDs, but reduced anterior ones by 32% and slowed propagation velocity. Riboflavin had no significant effect at neither recording site. Frontal Fos expression was decreased after lamotrigine and valproate, but not after riboflavin. Serum levels of administered drugs were within the range of those usually effective in patients. Our study shows that preventive anti-migraine drugs have differential effects on CSD. Lamotrigine has a marked suppressive effect which correlates with its rather selective action on the migraine aura. Valproate and riboflavin have no effect on the triggering of CSD, although they are effective in migraine without aura. Taken together, these results are compatible with a causal role of CSD in migraine with aura, but not in migraine without aura.
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Affiliation(s)
- Volodymyr Borysovych Bogdanov
- Headache Research Unit, GIGA-Neurosciences and Department of Neurology, Liège University, CHU Sart Tilman B36, T4, +1, B-4000, Liège, Belgium
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Baker KB, Schuster D, Cooperrider J, Machado AG. Deep brain stimulation of the lateral cerebellar nucleus produces frequency-specific alterations in motor evoked potentials in the rat in vivo. Exp Neurol 2010; 226:259-64. [PMID: 20816822 DOI: 10.1016/j.expneurol.2010.08.019] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2010] [Revised: 08/09/2010] [Accepted: 08/22/2010] [Indexed: 01/13/2023]
Abstract
The cerebral cortex is tightly and reciprocally linked to the cerebellum and the ascending dentato-thalalmo-cortical pathway influences widespread cortical regions. Using a rodent model of middle cerebral artery stroke, we showed previously that chronic, 20 Hz stimulation of the contralateral lateral cerebellar nucleus (LCN) improved motor recovery, while 50 Hz stimulation did not. Using motor evoked potentials (MEP) elicited by intracortical microstimulation, we now show the effect of LCN stimulation on motor cortex excitability as a function of pulse frequency in propofol-anesthetized rats. MEPs were recorded serially, at 15-s intervals, with cerebellar stimulation delivered in 10-min blocks at rates of 20, 30, 40, 50 or 100 Hz. Stimulation at 20, 30, 40 or 50 Hz enhanced the average MEP response across the block, with the maximal overall increase observed during 30 Hz stimulation. However, the effect varied as a function of both repeated trials within the block and LCN stimulation frequency, such that 40 Hz and 50 Hz stimulation showed a reduced effect over time. Stimulation at 100 Hz produced a transient increase in MEP amplitude in some animals; however the overall effect across the block was a trend towards reduced cortical excitability. These results suggest that direct stimulation of the LCN can yield frequency-dependent changes in cortical excitability and may provide a therapeutic approach to modulating cortical activity for the treatment of strokes or other focal cortical lesions, movement disorders and epilepsy.
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Affiliation(s)
- Kenneth B Baker
- Department of Neuroscience (NC-30), Cleveland Clinic Lerner Research Institute, Cleveland, OH 44195, USA
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Interleaved transcranial magnetic stimulation and fMRI suggests that lamotrigine and valproic acid have different effects on corticolimbic activity. Psychopharmacology (Berl) 2010; 209:233-44. [PMID: 20195575 DOI: 10.1007/s00213-010-1786-y] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/21/2009] [Accepted: 01/24/2010] [Indexed: 02/07/2023]
Abstract
RATIONALE Combined transcranial magnetic stimulation (TMS) and functional magnetic resonance imaging (fMRI) can be used to study anticonvulsant drugs. A previous study showed that lamotrigine (LTG) inhibited brain activation induced when TMS was applied over motor cortex, whereas it increased activation induced by TMS applied over prefrontal cortex. OBJECTIVES The present double-blind, placebo-controlled, crossover study in 30 healthy subjects again combined TMS and fMRI to test whether the effects seen previously with LTG would be confirmed and to compare these with a second anticonvulsant drug, valproic acid (VPA). RESULTS Statistical parametric mapping analysis showed that both LTG and VPA, compared to placebo, inhibited TMS-induced activation of the motor cortex. In contrast, when TMS was applied over prefrontal cortex, LTG increased the activation of limbic regions, confirming previous results; VPA had no effect. CONCLUSION We conclude that LTG and VPA have similar inhibitory effects on motor circuits, but differing effects on the prefrontal corticolimbic system. The study demonstrates that a combination of TMS and fMRI techniques may be useful in the study of the effects of neuroactive drugs on specific brain circuits.
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George MS, Aston-Jones G. Noninvasive techniques for probing neurocircuitry and treating illness: vagus nerve stimulation (VNS), transcranial magnetic stimulation (TMS) and transcranial direct current stimulation (tDCS). Neuropsychopharmacology 2010; 35:301-16. [PMID: 19693003 PMCID: PMC3055429 DOI: 10.1038/npp.2009.87] [Citation(s) in RCA: 235] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/13/2009] [Revised: 06/12/2009] [Accepted: 06/17/2009] [Indexed: 01/19/2023]
Abstract
Although the preceding chapters discuss much of the new knowledge of neurocircuitry of neuropsychiatric diseases, and an invasive approach to treatment, this chapter describes and reviews the noninvasive methods of testing circuit-based theories and treating neuropsychiatric diseases that do not involve implanting electrodes into the brain or on its surface. These techniques are transcranial magnetic stimulation, vagus nerve stimulation, and transcranial direct current stimulation. Two of these approaches have FDA approval as therapies.
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Affiliation(s)
- Mark S George
- Departments of Psychiatry, Radiology and Neuroscience, Institute of Psychiatry, MUSC Center for Advanced Imaging Research, Medical University of South Carolina, Charleston, SC 29425, USA.
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Palermo A, Fierro B, Giglia G, Cosentino G, Puma AR, Brighina F. Modulation of visual cortex excitability in migraine with aura: Effects of valproate therapy. Neurosci Lett 2009; 467:26-9. [DOI: 10.1016/j.neulet.2009.09.054] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2009] [Revised: 09/03/2009] [Accepted: 09/27/2009] [Indexed: 10/20/2022]
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Song C, Chen H, Wang X, Wang H, Wan Q. The efficacy and tolerability of lamotrigine adjunctive/monotherapy in patients with partial seizures refractory to poly-AEDs. ACTA ACUST UNITED AC 2009. [DOI: 10.1016/s1007-4376(09)60078-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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