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Kuo HI, Nitsche MA, Wu YT, Chang JC, Yang LK. Acute aerobic exercise modulates cognition and cortical excitability in adults with attention-deficit hyperactivity disorder (ADHD) and healthy controls. Psychiatry Res 2024; 340:116108. [PMID: 39116688 DOI: 10.1016/j.psychres.2024.116108] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/15/2024] [Revised: 06/07/2024] [Accepted: 07/25/2024] [Indexed: 08/10/2024]
Abstract
Evidence suggests aerobic exercise has beneficial effects on cognitive performance in adults with attention-deficit hyperactivity disorder (ADHD). The underlying mechanisms might depend on mechanisms of exercise-mediated brain physiology. The study aims to investigate the effects of acute aerobic exercise on cortical excitability and cognitive performance, and the correlation between these phenomena in adults with ADHD. Twenty-six drug-naïve ADHD adults, and twenty-six age-, and gender-matched healthy controls were assessed with respect to cortical excitability and cognitive performance before and after acute aerobic exercise (a single session for 30 min) or a control intervention. The results show significantly enhanced intracortical facilitation (ICF) and decreased short intracortical inhibition (SICI) after aerobic exercise in healthy subjects. In contrast, SICI was significantly enhanced following acute aerobic exercise in ADHD. In ADHD, furthermore inhibitory control and motor learning were significantly improved after the acute aerobic exercise intervention. Alterations of SICI induced by aerobic exercise, and inhibitory control and motor learning improvement were significantly positively correlated in the ADHD group. Aerobic exercise had partially antagonistic effects in healthy controls, and ADHD patients. Furthermore, aerobic exercise-induced cognition-enhancing effects in ADHD depend on specific alterations of brain physiology, which differ from healthy humans.
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Affiliation(s)
- Hsiao-I Kuo
- School and Graduate Institute of Physical Therapy, National Taiwan University, Taipei 10055, Taiwan.
| | - Michael A Nitsche
- Department Psychology and Neurosciences, Leibniz Research Center for Working Environment and Human Factors, 44139 Dortmund, Germany; Bielefeld University, University Hospital OWL, Protestant Hospital of Bethel Foundation, University Clinic of Psychiatry and Psychotherapy and University Clinic of Child and Adolescent Psychiatry and Psychotherapy, 33615 Bielefeld, Germany
| | - Yen-Tzu Wu
- School and Graduate Institute of Physical Therapy, National Taiwan University, Taipei 10055, Taiwan
| | - Jung-Chi Chang
- Department of Psychiatry, National Taiwan University Hospital, Taipei 10055, Taiwan
| | - Li-Kuang Yang
- Department of Psychiatry, National Taiwan University Hospital, Taipei 10055, Taiwan
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2
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Kuo HI, Sun JL, Nitsche M, Chang JC. An investigation of the acute effects of aerobic exercise on executive function and cortical excitability in adolescents with attention deficit hyperactivity disorder (ADHD). Eur Child Adolesc Psychiatry 2024:10.1007/s00787-024-02467-x. [PMID: 38727819 DOI: 10.1007/s00787-024-02467-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/19/2024] [Accepted: 05/01/2024] [Indexed: 09/28/2024]
Abstract
Previous studies have shown that aerobic exercise has beneficial effects on executive function in adolescents with attention-deficit hyperactivity disorder (ADHD). The underlying mechanisms could be partially due to aerobic exercise-induced cortical excitability modulation. The aim of this study was to explore the effects of acute aerobic exercise on executive functions and cortical excitability and the association between these phenomena in adolescents with ADHD. The study was conducted using a complete crossover design. Executive functions (inhibitory control, working memory, and planning) and cortical excitability were assessed in twenty-four drug-naïve adolescents with ADHD before and after acute aerobic exercise or a control intervention. Inhibitory control, working memory, and planning improved after acute aerobic exercise in adolescents with ADHD. Moreover, cortical excitability monitored by transcranial magnetic stimulation (TMS) decreased after intervention in this population. Additionally, improvements in inhibitory control and working memory performance were associated with enhanced cortical inhibition. The findings provide indirect preliminary evidence for the assumption that changes in cortical excitability induced by aerobic exercise partially contribute to improvements in executive function in adolescents with ADHD.
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Affiliation(s)
- Hsiao-I Kuo
- School and graduate institute of physical therapy, College of Medicine, National Taiwan University, No.17, Xu-Zhou Road, Taipei, 10055, Taiwan.
| | - Jia-Ling Sun
- School and graduate institute of physical therapy, College of Medicine, National Taiwan University, No.17, Xu-Zhou Road, Taipei, 10055, Taiwan
| | - Michael Nitsche
- Department Psychology and Neurosciences, Leibniz Research Center for Working Environment and Human Factors, Ardeystrasse 67, 44139, Dortmund, Germany
| | - Jung-Chi Chang
- Department of Psychiatry, National Taiwan University Hospital, No. 7, Zhongshan S Road, Taipei, 10055, Taiwan
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3
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Thorstensen JR, Henderson TT, Kavanagh JJ. Serotonergic and noradrenergic contributions to motor cortical and spinal motoneuronal excitability in humans. Neuropharmacology 2024; 242:109761. [PMID: 37838337 DOI: 10.1016/j.neuropharm.2023.109761] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2023] [Revised: 10/05/2023] [Accepted: 10/11/2023] [Indexed: 10/16/2023]
Abstract
Animal models indicate that motor behaviour is shaped by monoamine neuromodulators released diffusely throughout the brain and spinal cord. As an alternative to conducting a single study to explore the effects of neuromodulators on the human motor system, we have identified and collated human experiments investigating motor effects of well-characterised drugs that act on serotonergic and noradrenergic networks. In doing so, we present strong neuropharmacology evidence that human motor pathways are affected by neuromodulators across both healthy and clinical populations, insight that cannot be determined from a single reductionist experiment. We have focused our review on the effects that monoaminergic drugs have on muscle responses to non-invasive stimulation of the motor cortex and peripheral nerves, and other closely related tests of motoneuron excitability, and discuss how these measurement techniques elucidate the effects of neuromodulators at motor cortical and spinal motoneuronal levels. Although there is some heterogeneity in study methods, we find drugs acting to enhance extracellular concentrations of serotonin tend to reduce the excitability of the human motor cortex, and enhanced extracellular concentrations of noradrenaline increases motor cortical excitability by enhancing intracortical facilitation and reducing inhibition. Both monoamines tend to enhance the excitability of spinal motoneurons. Overall, this review details the importance of neuromodulators for the output of human motor pathways and suggests that commonly prescribed monoaminergic drugs target the motor system in addition to their typical psychiatric/neurological indications.
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Affiliation(s)
- Jacob R Thorstensen
- School of Biomedical Sciences, The University of Queensland, Brisbane, Australia.
| | - Tyler T Henderson
- Menzies Health Institute Queensland, Griffith University, Gold Coast, Australia
| | - Justin J Kavanagh
- Menzies Health Institute Queensland, Griffith University, Gold Coast, Australia
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Tang VM, Ibrahim C, Rodak T, Goud R, Blumberger DM, Voineskos D, Le Foll B. Managing substance use in patients receiving therapeutic repetitive transcranial magnetic stimulation: A scoping review. Neurosci Biobehav Rev 2023; 155:105477. [PMID: 38007879 DOI: 10.1016/j.neubiorev.2023.105477] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2023] [Revised: 11/16/2023] [Accepted: 11/18/2023] [Indexed: 11/28/2023]
Abstract
Repetitive Transcranial Magnetic Stimulation (rTMS) is an invaluable treatment option for neuropsychiatric disorders. Co-occurring recreational and nonmedical substance use can be common in those presenting for rTMS treatment, and it is unknown how it may affect the safety and efficacy of rTMS for the treatment of currently approved neuropsychiatric indications. This scoping review aimed to map the literature on humans receiving rTMS and had a history of any type of substance use. The search identified 274 articles providing information on inclusion/exclusion criteria, withdrawal criteria, safety protocols, type of rTMS and treatment parameters, adverse events and effect on primary outcomes that related to substance use. There are neurophysiological effects of substance use on cortical excitability, although the relevance to clinical rTMS practice is unknown. The current literature supports the safety and feasibility of delivering rTMS to those who have co-occurring neuropsychiatric disorder and substance use. However, specific details on how varying degrees of substance use alters the safety, efficacy, and mechanisms of rTMS remains poorly described.
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Affiliation(s)
- Victor M Tang
- Addictions Division, Centre for Addiction and Mental Health, Canada; Institute for Medical Science, Temerty Faculty of Medicine, University of Toronto, Canada; Department of Psychiatry, Temerty Faculty of Medicine, University of Toronto, Canada; Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Canada; Institute of Mental Health Policy Research, Centre for Addiction and Mental Health, Canada.
| | - Christine Ibrahim
- Addictions Division, Centre for Addiction and Mental Health, Canada; Institute for Medical Science, Temerty Faculty of Medicine, University of Toronto, Canada
| | - Terri Rodak
- CAMH Mental Health Sciences Library, Department of Education, Centre for Addiction and Mental Health, Canada
| | - Rachel Goud
- Addictions Division, Centre for Addiction and Mental Health, Canada
| | - Daniel M Blumberger
- Institute for Medical Science, Temerty Faculty of Medicine, University of Toronto, Canada; Department of Psychiatry, Temerty Faculty of Medicine, University of Toronto, Canada; Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Canada; Temerty Centre for Therapeutic Brain Intervention, Centre for Addiction and Mental Health, Canada
| | - Daphne Voineskos
- Institute for Medical Science, Temerty Faculty of Medicine, University of Toronto, Canada; Department of Psychiatry, Temerty Faculty of Medicine, University of Toronto, Canada; Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Canada; Temerty Centre for Therapeutic Brain Intervention, Centre for Addiction and Mental Health, Canada; Poul Hansen Family Centre for Depression, Krembil Research Institute, Toronto Western Hospital, University Health Network, Canada
| | - Bernard Le Foll
- Addictions Division, Centre for Addiction and Mental Health, Canada; Institute for Medical Science, Temerty Faculty of Medicine, University of Toronto, Canada; Department of Psychiatry, Temerty Faculty of Medicine, University of Toronto, Canada; Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Canada; Institute of Mental Health Policy Research, Centre for Addiction and Mental Health, Canada; CAMH Mental Health Sciences Library, Department of Education, Centre for Addiction and Mental Health, Canada; Temerty Centre for Therapeutic Brain Intervention, Centre for Addiction and Mental Health, Canada; Poul Hansen Family Centre for Depression, Krembil Research Institute, Toronto Western Hospital, University Health Network, Canada; Department of Pharmacology and Toxicology, Temerty Faculty of Medicine, University of Toronto, Canada; Department of Family and Community Medicine, Temerty Faculty of Medicine, University of Toronto, Canada; Waypoint Research Institute, Waypoint Centre for Mental Health Care, Penetanguishene, Canada
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Gonçalves FDT, Pacheco-Barrios K, Rebello-Sanchez I, Castelo-Branco L, de Melo PS, Parente J, Cardenas-Rojas A, Firigato I, Pessotto AV, Imamura M, Simis M, Battistella L, Fregni F. Association of Mu opioid receptor (A118G) and BDNF (G196A) polymorphisms with rehabilitation-induced cortical inhibition and analgesic response in chronic osteoarthritis pain. Int J Clin Health Psychol 2023; 23:100330. [PMID: 36199368 PMCID: PMC9508345 DOI: 10.1016/j.ijchp.2022.100330] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2022] [Revised: 07/23/2022] [Accepted: 07/23/2022] [Indexed: 01/02/2023] Open
Abstract
Background/objective Chronic pain due to osteoarthritis (OA) is a prevalent cause of global disability. New biomarkers are needed to improve treatment allocation, and genetic polymorphisms are promising candidates. Method We aimed to assess the association of OPRM1 (A118G and C17T) and brain-derived neurotrophic factor (BDNF [G196A]) polymorphisms with pain-related outcomes and motor cortex excitability metrics (measured by transcranial magnetic stimulation) in 113 knee OA patients with chronic pain. We performed adjusted multivariate regression analyses to compare carriers versus non-carriers in terms of clinical and neurophysiological characteristics at baseline, and treatment response (pain reduction and increased cortical inhibitory tonus) after rehabilitation. Results Compared to non-carriers, participants with polymorphisms on both OPRM1 (A118G) and BDNF (G196A) genes were less likely to improve pain after rehabilitation (85 and 72% fewer odds of improvement, respectively). Likewise, both carriers of OPRM1 polymorphisms (A118G and C17T) were also less likely to improve cortical inhibition (short intracortical inhibition [SICI], and intracortical facilitation [ICF], respectively). While pain and cortical inhibition improvement did not correlate in the total sample, the presence of OPRM1 (A118G) and BDNF (G196A) polymorphisms moderated this relationship. Conclusions These results underscore the promising role of combining genetic and neurophysiological markers to endotype the treatment response in this population.
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Gross J, Faber NS, Kappes A, Nussberger AM, Cowen PJ, Browning M, Kahane G, Savulescu J, Crockett MJ, De Dreu CK. When Helping Is Risky: The Behavioral and Neurobiological Trade-off of Social and Risk Preferences. Psychol Sci 2021; 32:1842-1855. [PMID: 34705578 PMCID: PMC7614101 DOI: 10.1177/09567976211015942] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
Helping other people can entail risks for the helper. For example, when treating infectious patients, medical volunteers risk their own health. In such situations, decisions to help should depend on the individual's valuation of others' well-being (social preferences) and the degree of personal risk the individual finds acceptable (risk preferences). We investigated how these distinct preferences are psychologically and neurobiologically integrated when helping is risky. We used incentivized decision-making tasks (Study 1; N = 292 adults) and manipulated dopamine and norepinephrine levels in the brain by administering methylphenidate, atomoxetine, or a placebo (Study 2; N = 154 adults). We found that social and risk preferences are independent drivers of risky helping. Methylphenidate increased risky helping by selectively altering risk preferences rather than social preferences. Atomoxetine influenced neither risk preferences nor social preferences and did not affect risky helping. This suggests that methylphenidate-altered dopamine concentrations affect helping decisions that entail a risk to the helper.
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Affiliation(s)
- Jörg Gross
- Institute of Psychology, Leiden University,Corresponding author: Jörg Gross, Leiden University, Institute of Psychology, Wassenaarseweg 52, 2300 RB Leiden, , +31 71 527 2727
| | - Nadira S. Faber
- College of Life and Environmental Sciences, University of Exeter,Oxford Uehiro Centre for Practical Ethics, University of Oxford
| | | | | | - Philip J Cowen
- Department of Psychiatry, University of Oxford,Oxford Health NHS Foundation Trust, Oxford
| | - Michael Browning
- Department of Psychiatry, University of Oxford,Oxford Health NHS Foundation Trust, Oxford
| | - Guy Kahane
- Oxford Uehiro Centre for Practical Ethics, University of Oxford
| | | | | | - Carsten K.W. De Dreu
- Institute of Psychology, Leiden University,Center for Research in Experimental Economics and Political Decision Making (CREED), University of Amsterdam
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Turco CV, Nelson AJ. Transcranial Magnetic Stimulation to Assess Exercise-Induced Neuroplasticity. FRONTIERS IN NEUROERGONOMICS 2021; 2:679033. [PMID: 38235229 PMCID: PMC10790852 DOI: 10.3389/fnrgo.2021.679033] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/10/2021] [Accepted: 05/06/2021] [Indexed: 01/19/2024]
Abstract
Aerobic exercise facilitates neuroplasticity and has been linked to improvements in cognitive and motor function. Transcranial magnetic stimulation (TMS) is a non-invasive technique that can be used to quantify changes in neurophysiology induced by exercise. The present review summarizes the single- and paired-pulse TMS paradigms that can be used to probe exercise-induced neuroplasticity, the optimal stimulation parameters and the current understanding of the neurophysiology underlying each paradigm. Further, this review amalgamates previous research exploring the modulation of these paradigms with exercise-induced neuroplasticity in healthy and clinical populations and highlights important considerations for future TMS-exercise research.
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Affiliation(s)
| | - Aimee J. Nelson
- Department of Kinesiology, McMaster University, Hamilton, ON, Canada
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8
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Pedapati EV, Mooney LN, Wu SW, Erickson CA, Sweeney JA, Shaffer RC, Horn PS, Wink LK, Gilbert DL. Motor cortex facilitation: a marker of attention deficit hyperactivity disorder co-occurrence in autism spectrum disorder. Transl Psychiatry 2019; 9:298. [PMID: 31723120 PMCID: PMC6853984 DOI: 10.1038/s41398-019-0614-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/24/2019] [Revised: 09/23/2019] [Accepted: 10/15/2019] [Indexed: 01/06/2023] Open
Abstract
The neural correlates distinguishing youth with Autism Spectrum Disorder (ASD-) and ASD with co-occurring Attention Deficit Hyperactivity Disorder (ASD+) are poorly understood despite significant phenotypic and prognostic differences. Paired-pulse transcranial magnetic stimulation (TMS) measures, including intracortical facilitation (ICF), short interval cortical inhibition (SICI), and cortical silent period (CSP) were measured in an age matched cohort of youth with ASD- (n = 20), ASD + (n = 29), and controls (TDC) (n = 24). ASD- and ASD+ groups did not differ by IQ or social functioning; however, ASD+ had significantly higher inattention and hyperactivity ratings. ICF (higher ratio indicates greater facilitation) in ASD+ (Mean 1.0, SD 0.19) was less than ASD- (Mean 1.3, SD 0.36) or TDC (Mean 1.2, SD 0.24) (F2,68 = 6.5, p = 0.003; post-hoc tests, ASD+ vs either TDC or ASD-, p ≤ 0.05). No differences were found between groups for SICI or age corrected active/resting motor threshold (AMT/RMT). Across all ASD youth (ASD- and ASD+), ICF was inversely correlated with worse inattention (Conners-3 Inattention (r = -0.41; p < 0.01) and ADHDRS-IV Inattention percentile (r = -0.422, p < 0.01) scores. ICF remains intact in ASD- but is impaired in ASD+. Lack of ICF is associated with inattention and executive function across ASD. Taken with the present findings, ADHD may have a distinct electrophysiological "signature" in ASD youth. ICF may constitute an emerging biomarker to study the physiology of ADHD in ASD, which may align with disease prognosis or treatment response.
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Affiliation(s)
- Ernest V. Pedapati
- 0000 0000 9025 8099grid.239573.9Divisions of Child and Adolescent Psychiatry, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH USA ,0000 0000 9025 8099grid.239573.9Division of Neurology, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH USA
| | - Lindsey N. Mooney
- 0000 0000 9025 8099grid.239573.9Division of Neurology, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH USA ,0000 0004 1936 9684grid.27860.3bDepartment of Psychology, University of California, Davis, CA USA
| | - Steve W. Wu
- 0000 0000 9025 8099grid.239573.9Divisions of Child and Adolescent Psychiatry, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH USA
| | - Craig A. Erickson
- 0000 0000 9025 8099grid.239573.9Division of Neurology, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH USA
| | - John A. Sweeney
- 0000 0001 2179 9593grid.24827.3bDepartment of Psychiatry, University of Cincinnati College of Medicine, Cincinnati, OH USA
| | - Rebecca C. Shaffer
- 0000 0000 9025 8099grid.239573.9Developmental and Behavioral Pediatrics, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH USA
| | - Paul S. Horn
- 0000 0000 9025 8099grid.239573.9Divisions of Child and Adolescent Psychiatry, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH USA ,0000 0000 9025 8099grid.239573.9Divisions of Biostatistics and Epidemiology, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH USA
| | - Logan K. Wink
- 0000 0000 9025 8099grid.239573.9Division of Neurology, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH USA
| | - Donald L. Gilbert
- 0000 0000 9025 8099grid.239573.9Divisions of Child and Adolescent Psychiatry, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH USA
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9
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Port RG, Oberman LM, Roberts TPL. Revisiting the excitation/inhibition imbalance hypothesis of ASD through a clinical lens. Br J Radiol 2019; 92:20180944. [PMID: 31124710 PMCID: PMC6732925 DOI: 10.1259/bjr.20180944] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2018] [Revised: 04/19/2019] [Accepted: 05/21/2019] [Indexed: 12/22/2022] Open
Abstract
Autism spectrum disorder (ASD) currently affects 1 in 59 children, although the aetiology of this disorder remains unknown. Faced with multiple seemingly disparate and noncontiguous neurobiological alterations, Rubenstein and Merzenich hypothesized that imbalances between excitatory and inhibitory neurosignaling (E/I imbalance) underlie ASD. Since this initial statement, there has been a major focus examining this exact topic spanning both clinical and preclinical realms. The purpose of this article is to review the clinical neuroimaging literature surrounding E/I imbalance as an aetiology of ASD. Evidence for E/I imbalance is presented from several complementary clinical techniques including magnetic resonance spectroscopy, magnetoencephalography and transcranial magnetic stimulation. Additionally, two GABAergic potential interventions for ASD, which explicitly attempt to remediate E/I imbalance, are reviewed. The current literature suggests E/I imbalance as a useful framework for discussing the neurobiological etiology of ASD in at least a subset of affected individuals. While not constituting a completely unifying aetiology, E/I imbalance may be relevant as one of several underlying neuropathophysiologies that differentially affect individuals with ASD. Such statements do not diminish the value of the E/I imbalance concept-instead they suggest a possible role for the characterization of E/I imbalance, as well as other underlying neuropathophysiologies, in the biologically-based subtyping of individuals with ASD for potential applications including clinical trial enrichment as well as treatment triage.
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Affiliation(s)
| | - Lindsay M Oberman
- Center for Neuroscience and Regenerative Medicine, Henry M. Jackson Foundation for the Advancement of Military Medicine, Rockville, Maryland
| | - Timothy PL Roberts
- Department of Radiology, Lurie Family Foundations MEG Imaging Center, Children’s Hospital of Philadelphia, Pennsylvania
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Berger C, Müller-Godeffroy J, Marx I, Reis O, Buchmann J, Dück A. Methylphenidate promotes the interaction between motor cortex facilitation and attention in healthy adults: A combined study using event-related potentials and transcranial magnetic stimulation. Brain Behav 2018; 8:e01155. [PMID: 30417982 PMCID: PMC6305964 DOI: 10.1002/brb3.1155] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/17/2018] [Revised: 09/27/2018] [Accepted: 10/14/2018] [Indexed: 11/25/2022] Open
Abstract
OBJECTIVE This study investigated simultaneously the impact of methylphenidate (MPH) on the interaction of inhibitory and facilitative pathways in regions processing motor and cognitive functions. METHOD Neural markers of attention and response control (event-related potentials) and motor cortical excitability (transcranial magnetic stimulation) and their pharmacological modulation by MPH were measured simultaneously in a sample of healthy adults (n = 31) performing a cued choice reaction test. RESULTS Methylphenidate modulated attentional gating and response preparation processes (increased contingent negative variation) and response inhibition (increased nogo P3). N1, cue- and go-P3 were not affected by MPH. Motor cortex facilitation, measured with long-interval cortical facilitation, was increased under MPH in the nogo condition and was positively correlated with the P3 amplitude. CONCLUSION Methylphenidate seems particularly to enhance response preparation processes. The MPH-induced increased motor cortex facilitation during inhibitory task demands was accompanied by increased terminal response inhibition control, probably as a compensatory process.
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Affiliation(s)
- Christoph Berger
- Department of Psychiatry, Neurology, Psychosomatics, Psychotherapy in Childhood and Adolescence, University Medical Center of Rostock, Rostock, Germany
| | - Juliane Müller-Godeffroy
- Department of Psychiatry, Neurology, Psychosomatics, Psychotherapy in Childhood and Adolescence, University Medical Center of Rostock, Rostock, Germany
| | - Ivo Marx
- Department of Psychiatry, Neurology, Psychosomatics, Psychotherapy in Childhood and Adolescence, University Medical Center of Rostock, Rostock, Germany
| | - Olaf Reis
- Department of Psychiatry, Neurology, Psychosomatics, Psychotherapy in Childhood and Adolescence, University Medical Center of Rostock, Rostock, Germany
| | - Johannes Buchmann
- Department of Psychiatry, Neurology, Psychosomatics, Psychotherapy in Childhood and Adolescence, University Medical Center of Rostock, Rostock, Germany
| | - Alexander Dück
- Department of Psychiatry, Neurology, Psychosomatics, Psychotherapy in Childhood and Adolescence, University Medical Center of Rostock, Rostock, Germany
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11
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Connecting clinical aspects to corticomotor excitability in restless legs syndrome: a TMS study. Sleep Med 2018; 49:105-112. [DOI: 10.1016/j.sleep.2018.05.002] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/08/2018] [Revised: 04/27/2018] [Accepted: 05/04/2018] [Indexed: 01/07/2023]
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12
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Hanlon CA, Dowdle LT, Henderson JS. Modulating Neural Circuits with Transcranial Magnetic Stimulation: Implications for Addiction Treatment Development. Pharmacol Rev 2018; 70:661-683. [PMID: 29945899 PMCID: PMC6020107 DOI: 10.1124/pr.116.013649] [Citation(s) in RCA: 58] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Although the last 50 years of clinical and preclinical research have demonstrated that addiction is a brain disease, we still have no neural circuit-based treatments for substance dependence or cue reactivity at large. Now, for the first time, it appears that a noninvasive brain stimulation technique known as transcranial magnetic stimulation (TMS), which is Food and Drug Administration approved to treat depression, may be the first tool available to fill this critical void in addiction treatment development. The goals of this review are to 1) introduce TMS as a tool to induce causal change in behavior, cortical excitability, and frontal-striatal activity; 2) describe repetitive TMS (rTMS) as an interventional tool; 3) provide an overview of the studies that have evaluated rTMS as a therapeutic tool for alcohol and drug use disorders; and 4) outline a conceptual framework for target selection when designing future rTMS clinical trials in substance use disorders. The manuscript concludes with some suggestions for methodological innovation, specifically with regard to combining rTMS with pharmacotherapy as well as cognitive behavioral training paradigms. We have attempted to create a comprehensive manuscript that provides the reader with a basic set of knowledge and an introduction to the primary experimental questions that will likely drive the field of TMS treatment development forward for the next several years.
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Affiliation(s)
- Colleen A Hanlon
- Departments of Psychiatry (C.A.H., L.T.D., J.S.H.) and Neurosciences (C.A.H., L.T.D.), Medical University of South Carolina, Charleston, South Carolina; and Ralph Johnson VA Medical Center, Charleston, South Carolina (C.A.H.)
| | - Logan T Dowdle
- Departments of Psychiatry (C.A.H., L.T.D., J.S.H.) and Neurosciences (C.A.H., L.T.D.), Medical University of South Carolina, Charleston, South Carolina; and Ralph Johnson VA Medical Center, Charleston, South Carolina (C.A.H.)
| | - J Scott Henderson
- Departments of Psychiatry (C.A.H., L.T.D., J.S.H.) and Neurosciences (C.A.H., L.T.D.), Medical University of South Carolina, Charleston, South Carolina; and Ralph Johnson VA Medical Center, Charleston, South Carolina (C.A.H.)
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Rubio B, Boes AD, Laganiere S, Rotenberg A, Jeurissen D, Pascual-Leone A. Noninvasive Brain Stimulation in Pediatric Attention-Deficit Hyperactivity Disorder (ADHD): A Review. J Child Neurol 2016; 31:784-96. [PMID: 26661481 PMCID: PMC4833526 DOI: 10.1177/0883073815615672] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/04/2015] [Accepted: 07/10/2015] [Indexed: 01/08/2023]
Abstract
Attention-deficit hyperactivity disorder (ADHD) is one of the most prevalent neurodevelopmental disorders in the pediatric population. The clinical management of ADHD is currently limited by a lack of reliable diagnostic biomarkers and inadequate therapy for a minority of patients who do not respond to standard pharmacotherapy. There is optimism that noninvasive brain stimulation may help to address these limitations. Transcranial magnetic stimulation and transcranial direct current stimulation are 2 methods of noninvasive brain stimulation that modulate cortical excitability and brain network activity. Transcranial magnetic stimulation can be used diagnostically to probe cortical neurophysiology, whereas daily use of repetitive transcranial magnetic stimulation or transcranial direct current stimulation can induce long-lasting and potentially therapeutic changes in targeted networks. In this review, we highlight research showing the potential diagnostic and therapeutic applications of transcranial magnetic stimulation and transcranial direct current stimulation in pediatric ADHD. We also discuss the safety and ethics of using these tools in the pediatric population.
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Affiliation(s)
- Belen Rubio
- Child and Adolescent Psychiatry Department, Hospital Universitario de Canarias, La Laguna, Tenerife, Spain Both are co-primary authors
| | - Aaron D Boes
- Berenson-Allen Center for Noninvasive Brain Stimulation, Division of Cognitive Neurology, Department of Neurology, Harvard Medical School and Beth Israel Deaconess Medical Center, Boston, MA, USA Harvard Medical School, Department of Pediatric Neurology, Massachusetts General Hospital, Boston, MA, USA Both are co-primary authors.
| | - Simon Laganiere
- Berenson-Allen Center for Noninvasive Brain Stimulation, Division of Cognitive Neurology, Department of Neurology, Harvard Medical School and Beth Israel Deaconess Medical Center, Boston, MA, USA
| | - Alexander Rotenberg
- Berenson-Allen Center for Noninvasive Brain Stimulation, Division of Cognitive Neurology, Department of Neurology, Harvard Medical School and Beth Israel Deaconess Medical Center, Boston, MA, USA Pediatric Neuromodulation Program, Division of Epilepsy and Neurophysiology, Department of Neurology, Children's Hospital Boston, Harvard Medical School, Boston, MA, USA
| | - Danique Jeurissen
- Berenson-Allen Center for Noninvasive Brain Stimulation, Division of Cognitive Neurology, Department of Neurology, Harvard Medical School and Beth Israel Deaconess Medical Center, Boston, MA, USA Department of Vision and Cognition, Netherlands Institute for Neuroscience, Royal Netherlands Academy of Arts and Sciences, Amsterdam, The Netherlands
| | - Alvaro Pascual-Leone
- Berenson-Allen Center for Noninvasive Brain Stimulation, Division of Cognitive Neurology, Department of Neurology, Harvard Medical School and Beth Israel Deaconess Medical Center, Boston, MA, USA
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14
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Norepinephrine versus dopamine and their interaction in modulating synaptic function in the prefrontal cortex. Brain Res 2016; 1641:217-33. [PMID: 26790349 DOI: 10.1016/j.brainres.2016.01.005] [Citation(s) in RCA: 109] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2015] [Revised: 12/16/2015] [Accepted: 01/05/2016] [Indexed: 01/11/2023]
Abstract
Among the neuromodulators that regulate prefrontal cortical circuit function, the catecholamine transmitters norepinephrine (NE) and dopamine (DA) stand out as powerful players in working memory and attention. Perturbation of either NE or DA signaling is implicated in the pathogenesis of several neuropsychiatric disorders, including attention deficit hyperactivity disorder (ADHD), post-traumatic stress disorder (PTSD), schizophrenia, and drug addiction. Although the precise mechanisms employed by NE and DA to cooperatively control prefrontal functions are not fully understood, emerging research indicates that both transmitters regulate electrical and biochemical aspects of neuronal function by modulating convergent ionic and synaptic signaling in the prefrontal cortex (PFC). This review summarizes previous studies that investigated the effects of both NE and DA on excitatory and inhibitory transmissions in the prefrontal cortical circuitry. Specifically, we focus on the functional interaction between NE and DA in prefrontal cortical local circuitry, synaptic integration, signaling pathways, and receptor properties. Although it is clear that both NE and DA innervate the PFC extensively and modulate synaptic function by activating distinctly different receptor subtypes and signaling pathways, it remains unclear how these two systems coordinate their actions to optimize PFC function for appropriate behavior. Throughout this review, we provide perspectives and highlight several critical topics for future studies. This article is part of a Special Issue entitled SI: Noradrenergic System.
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15
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Oberman LM, Enticott PG, Casanova MF, Rotenberg A, Pascual-Leone A, McCracken JT. Transcranial magnetic stimulation in autism spectrum disorder: Challenges, promise, and roadmap for future research. Autism Res 2015; 9:184-203. [PMID: 26536383 DOI: 10.1002/aur.1567] [Citation(s) in RCA: 59] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2015] [Revised: 08/25/2015] [Accepted: 09/01/2015] [Indexed: 12/26/2022]
Abstract
Autism Spectrum Disorder (ASD) is a behaviorally defined complex neurodevelopmental syndrome characterized by impairments in social communication, by the presence of restricted and repetitive behaviors, interests and activities, and by abnormalities in sensory reactivity. Transcranial magnetic stimulation (TMS) is a promising, emerging tool for the study and potential treatment of ASD. Recent studies suggest that TMS measures provide rapid and noninvasive pathophysiological ASD biomarkers. Furthermore, repetitive TMS (rTMS) may represent a novel treatment strategy for reducing some of the core and associated ASD symptoms. However, the available literature on the TMS use in ASD is preliminary, composed of studies with methodological limitations. Thus, off-label clinical rTMS use for therapeutic interventions in ASD without an investigational device exemption and outside of an IRB approved research trial is premature pending further, adequately powered and controlled trials. Leaders in this field have gathered annually for a two-day conference (prior to the 2014 and 2015 International Meeting for Autism Research, IMFAR) to share recent progress, promote collaboration across laboratories, and establish consensus on protocols. Here we review the literature in the use of TMS in ASD in the context of the unique challenges required for the study and exploration of treatment strategies in this population. We also suggest future directions for this field of investigations. While its true potential in ASD has yet to be delineated, TMS represents an innovative research tool and a novel, possibly transformative approach to the treatment of neurodevelopmental disorders.
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Affiliation(s)
- Lindsay M Oberman
- Neuroplasticity and Autism Spectrum Disorder Program and Department of Psychiatry and Human Behavior, E.P. Bradley Hospital and Warren Alpert Medical School, Brown University, Providence, Rhode, Island
| | - Peter G Enticott
- Cognitive Neuroscience Unit, School of Psychology, Deakin University, Burwood, Victoria, Australia
| | - Manuel F Casanova
- Department of Psychiatry and Behavioral Science, University of Louisville, Louisville, Kentucky
| | - Alexander Rotenberg
- Neuromodulation Program, Department of Neurology, Boston Children's Hospital and Harvard Medical School, Boston, Massachusetts
| | - Alvaro Pascual-Leone
- Neuromodulation Program, Department of Neurology, Boston Children's Hospital and Harvard Medical School, Boston, Massachusetts.,Berenson-Allen Center for Noninvasive Brain Stimulation, Department of Neurology, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, Massachusetts
| | - James T McCracken
- Department of Psychiatry and Biobehavioral Sciences, David Geffen School of Medicine at UCLA, Los Angeles, California
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Attention-Deficit/Hyperactivity Disorder-like Phenotype in a Mouse Model with Impaired Actin Dynamics. Biol Psychiatry 2015; 78:95-106. [PMID: 24768258 DOI: 10.1016/j.biopsych.2014.03.011] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/15/2013] [Revised: 03/05/2014] [Accepted: 03/05/2014] [Indexed: 11/23/2022]
Abstract
BACKGROUND Actin depolymerizing proteins of the actin depolymerizing factor (ADF)/cofilin family are essential for actin dynamics, which is critical for synaptic function. Two ADF/cofilin family members, ADF and n-cofilin, are highly abundant in the brain, where they are present in excitatory synapses. Previous studies demonstrated the relevance of n-cofilin for postsynaptic plasticity, associative learning, and anxiety. These studies also suggested overlapping functions for ADF and n-cofilin. METHODS We performed pharmacobehavioral, electrophysiologic, and electron microscopic studies on ADF and n-cofilin single mutants and double mutants (named ACC mice) to characterize the importance of ADF/cofilin activity for synapse physiology and mouse behavior. RESULTS The ACC mice, but not single mutants, exhibited hyperlocomotion, impulsivity, and impaired working memory. Hyperlocomotion and impulsive behavior were reversed by methylphenidate, a psychostimulant commonly used for the treatment of attention-deficit/hyperactivity disorder (ADHD). Also, ACC mice displayed a disturbed morphology of striatal excitatory synapses, accompanied by strongly increased glutamate release. Blockade of dopamine or glutamate transmission resulted in normal locomotion. CONCLUSIONS Our study reveals that ADHD can result from a disturbed balance between excitation and inhibition in striatal circuits, providing novel insights into the mechanisms underlying this neurobehavioral disorder. Our results link actin dynamics to ADHD, suggesting that mutations in actin regulatory proteins may contribute to the etiology of ADHD in humans.
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Ziemann U, Reis J, Schwenkreis P, Rosanova M, Strafella A, Badawy R, Müller-Dahlhaus F. TMS and drugs revisited 2014. Clin Neurophysiol 2014; 126:1847-68. [PMID: 25534482 DOI: 10.1016/j.clinph.2014.08.028] [Citation(s) in RCA: 481] [Impact Index Per Article: 48.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2014] [Revised: 08/03/2014] [Accepted: 08/24/2014] [Indexed: 12/18/2022]
Abstract
The combination of pharmacology and transcranial magnetic stimulation to study the effects of drugs on TMS-evoked EMG responses (pharmaco-TMS-EMG) has considerably improved our understanding of the effects of TMS on the human brain. Ten years have elapsed since an influential review on this topic has been published in this journal (Ziemann, 2004). Since then, several major developments have taken place: TMS has been combined with EEG to measure TMS evoked responses directly from brain activity rather than by motor evoked potentials in a muscle, and pharmacological characterization of the TMS-evoked EEG potentials, although still in its infancy, has started (pharmaco-TMS-EEG). Furthermore, the knowledge from pharmaco-TMS-EMG that has been primarily obtained in healthy subjects is now applied to clinical settings, for instance, to monitor or even predict clinical drug responses in neurological or psychiatric patients. Finally, pharmaco-TMS-EMG has been applied to understand the effects of CNS active drugs on non-invasive brain stimulation induced long-term potentiation-like and long-term depression-like plasticity. This is a new field that may help to develop rationales of pharmacological treatment for enhancement of recovery and re-learning after CNS lesions. This up-dated review will highlight important knowledge and recent advances in the contribution of pharmaco-TMS-EMG and pharmaco-TMS-EEG to our understanding of normal and dysfunctional excitability, connectivity and plasticity of the human brain.
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Affiliation(s)
- Ulf Ziemann
- Department of Neurology & Stroke, and Hertie Institute for Clinical Brain Research, Eberhard-Karls-University Tübingen, Tübingen, Germany.
| | - Janine Reis
- Department of Neurology, Albert-Ludwigs-University Freiburg, Freiburg, Germany
| | - Peter Schwenkreis
- Department of Neurology, BG-University Hospital Bergmannsheil Bochum, Bochum, Germany
| | - Mario Rosanova
- Department of Biomedical and Clinical Sciences "Luigi Sacco", University of Milan, Milan, Italy; Fondazione Europea di Ricerca Biomedica, FERB Onlus, Milan, Italy
| | - Antonio Strafella
- Morton and Gloria Shulman Movement Disorder Unit & E.J. Safra Parkinson Disease Program, Toronto Western Hospital, UHN, University of Toronto, Ontario, Canada; Research Imaging Centre, Centre for Addiction and Mental Health, University of Toronto, Ontario, Canada
| | - Radwa Badawy
- Department of Neurology, Saint Vincent's Hospital, Fitzroy, The University of Melbourne, Parkville, Victoria, Australia; Department of Medicine, The University of Melbourne, Parkville, Victoria, Australia
| | - Florian Müller-Dahlhaus
- Department of Neurology & Stroke, and Hertie Institute for Clinical Brain Research, Eberhard-Karls-University Tübingen, Tübingen, Germany
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Chen TH, Wu SW, Welge JA, Dixon SG, Shahana N, Huddleston DA, Sarvis AR, Sallee FR, Gilbert DL. Reduced short interval cortical inhibition correlates with atomoxetine response in children with attention-deficit hyperactivity disorder (ADHD). J Child Neurol 2014; 29:1672-9. [PMID: 24413361 PMCID: PMC4092054 DOI: 10.1177/0883073813513333] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Clinical trials in children with attention-deficit hyperactivity disorder (ADHD) show variability in behavioral responses to the selective norepinephrine reuptake inhibitor atomoxetine. The objective of this study was to determine whether transcranial magnetic stimulation-evoked short interval cortical inhibition might be a biomarker predicting, or correlating with, clinical atomoxetine response. At baseline and after 4 weeks of atomoxetine treatment in 7- to 12-year-old children with ADHD, transcranial magnetic stimulation short interval cortical inhibition was measured, blinded to clinical improvement. Primary analysis was by multivariate analysis of covariance. Baseline short interval cortical inhibition did not predict clinical responses. However, paradoxically, after 4 weeks of atomoxetine, mean short interval cortical inhibition was reduced 31.9% in responders and increased 6.1% in nonresponders (analysis of covariance t 41 = 2.88; P = .0063). Percentage reductions in short interval cortical inhibition correlated with reductions in the ADHD Rating Scale (r = 0.50; P = .0005). In children ages 7 to 12 years with ADHD treated with atomoxetine, improvements in clinical symptoms are correlated with reductions in motor cortex short interval cortical inhibition.
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Affiliation(s)
- Tina H Chen
- University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - Steve W Wu
- Cincinnati Children’s Hospital Medical Center, Cincinnati, OH, USA
| | - Jeffrey A Welge
- Department of Psychiatry, University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - Stephan G Dixon
- Department of Psychiatry, University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - Nasrin Shahana
- Cincinnati Children’s Hospital Medical Center, Cincinnati, OH, USA
- Department of Neuroscience, University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | | | - Adam R Sarvis
- Department of Psychiatry, University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - Floyd R Sallee
- Department of Psychiatry, University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - Donald L Gilbert
- Cincinnati Children’s Hospital Medical Center, Cincinnati, OH, USA
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Hoegl T, Bender S, Buchmann J, Kratz O, Moll GH, Heinrich H. [Transcranial magnetic stimulation (TMS), inhibition processes and attention deficit/hyperactivity disorder (ADHD) - an overview]. ZEITSCHRIFT FUR KINDER-UND JUGENDPSYCHIATRIE UND PSYCHOTHERAPIE 2014; 42:415-28; quiz 428-9. [PMID: 25335520 DOI: 10.1024/1422-4917/a000320] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Motor system excitability can be tested by transcranial magnetic stimulation CFMS). In this article, an overview of recent methodological developments and research findings related to attention deficit/hyperactivity disorder (ADHD) is provided. Different TMS parameters that reflect the function of interneurons in the motor cortex may represent neurophysiological markers of inhibition in ADHD, particularly the so-called intracortical inhibition. In children with a high level of hyperactivity and impulsivity, intracortical inhibition was comparably low at rest as shortly before the execution of a movement. TMS-evoked potentials can also be measured in the EEG so that investigating processes of excitability is not restricted to motor areas in future studies. The effects of methylphenidate on motor system excitability may be interpreted in the sense of a 'fine-tuning' with these mainly dopaminergic effects also depending on genetic parameters (DAT1 transporter). A differentiated view on the organization of motor control can be achieved by a combined analysis of TMS parameters and event-related potentials. Applying this bimodal approach, strong evidence for a deviant implementation of motor control in children with ADHD and probably compensatory mechanisms (with involvement of the prefrontal cortex) was obtained. These findings, which contribute to a better understanding of hyperactivity/impulsivity, inhibitory processes and motor control in ADHD as well as the mechanisms of medication, underline the relevance of TMS as a neurophysiological method in ADHD research.
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Affiliation(s)
- Thomas Hoegl
- Kinder- u. Jugendabteilung für Psychische Gesundheit, Universitätsklinikum Erlangen
| | - Stephan Bender
- Klinik für Psychiatrie, Psychosomatik und Psychotherapie des Kindes- und Jugendalters, J. W. Goethe Universitätsklinikum, Frankfurt am Main
| | - Johannes Buchmann
- Klinik für Psychiatrie, Neurologie, Psychosomatik und Psychotherapie im Kindes- und Jugendalter, Zentrum Nervenheilkunde, Universität Rostock
| | - Oliver Kratz
- Kinder- u. Jugendabteilung für Psychische Gesundheit, Universitätsklinikum Erlangen
| | - Gunther H Moll
- Kinder- u. Jugendabteilung für Psychische Gesundheit, Universitätsklinikum Erlangen
| | - Hartmut Heinrich
- Kinder- u. Jugendabteilung für Psychische Gesundheit, Universitätsklinikum Erlangen Heckscher-Klinikum, München
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20
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Casula EP, Tarantino V, Basso D, Arcara G, Marino G, Toffolo GM, Rothwell JC, Bisiacchi PS. Low-frequency rTMS inhibitory effects in the primary motor cortex: Insights from TMS-evoked potentials. Neuroimage 2014; 98:225-32. [DOI: 10.1016/j.neuroimage.2014.04.065] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2013] [Revised: 04/14/2014] [Accepted: 04/24/2014] [Indexed: 10/25/2022] Open
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Fitoussi A, Le Moine C, De Deurwaerdère P, Laqui M, Rivalan M, Cador M, Dellu-Hagedorn F. Prefronto-subcortical imbalance characterizes poor decision-making: neurochemical and neural functional evidences in rats. Brain Struct Funct 2014; 220:3485-96. [PMID: 25134683 DOI: 10.1007/s00429-014-0868-8] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2014] [Accepted: 07/30/2014] [Indexed: 01/28/2023]
Abstract
A major challenge of decision-making research in recent years has been to develop models of poor decision-making to identify its neural bases. Toward this goal, we developed a Rat Gambling Task that discerns good and poor decision-makers in a complex and conflicting situation such as the human Iowa Gambling Task. Nothing is known about the role of the monoaminergic modulatory systems in shaping these phenotypes. Moreover, functional and temporal contributions of brain areas during poor compared to good decision-making remains elusive. Good and poor decision-makers were identified in the Rat Gambling Task. We investigated neurobiological correlates of decision-making capacities in (1) dopamine and serotonin turnovers using post-mortem tissue measurements, (2) the neural circuits differentially recruited during decision-making within the prefronto-subcortical network using cellular Fos immunodetection. Imbalance in monoamine metabolism was revealed in poor decision-makers, i.e. a higher infralimbic vs. lower amygdala serotonergic metabolism. Moreover, good decision-making recruited a wide prefronto-subcortical network but once good choices had been made, a disengagement of key prefrontal areas (insular and infralimbic cortices notably) and the amygdala was observed. By contrast, poor decision-making was associated with a strikingly low recruitment of the prefronto-subcortical network, together with sustained amygdala activity. Our results identify two complementary neurobiological substrates characterizing poor decision-makers: imbalanced monoaminergic systems at rest, congruent with their previously identified complex behavioral phenotype, and an aberrant low recruitment of key brain areas for executive functions and affective valence during the process of decision-making. These biomarkers could sustain vulnerability to developing poor decision-making related disorders.
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Affiliation(s)
- Aurélie Fitoussi
- University of Bordeaux, INCIA, CNRS UMR 5287, PB. 31, 146 rue Léo Saignat, 33076, Bordeaux Cedex, France.,CNRS, University of Bordeaux, INCIA, UMR 5287, 33000, Bordeaux, France
| | - Catherine Le Moine
- University of Bordeaux, INCIA, CNRS UMR 5287, PB. 31, 146 rue Léo Saignat, 33076, Bordeaux Cedex, France.,CNRS, University of Bordeaux, INCIA, UMR 5287, 33000, Bordeaux, France
| | - Philippe De Deurwaerdère
- University of Bordeaux, INCIA, CNRS UMR 5287, PB. 31, 146 rue Léo Saignat, 33076, Bordeaux Cedex, France.,CNRS, University of Bordeaux, IMN, UMR 5293, 33000, Bordeaux, France
| | - Matéo Laqui
- University of Bordeaux, INCIA, CNRS UMR 5287, PB. 31, 146 rue Léo Saignat, 33076, Bordeaux Cedex, France.,CNRS, University of Bordeaux, INCIA, UMR 5287, 33000, Bordeaux, France
| | - Marion Rivalan
- University of Bordeaux, INCIA, CNRS UMR 5287, PB. 31, 146 rue Léo Saignat, 33076, Bordeaux Cedex, France.,CNRS, University of Bordeaux, INCIA, UMR 5287, 33000, Bordeaux, France.,Institut of Cognitive Neurobiology, Humboldt University Berlin, Berlin, Germany
| | - Martine Cador
- University of Bordeaux, INCIA, CNRS UMR 5287, PB. 31, 146 rue Léo Saignat, 33076, Bordeaux Cedex, France.,CNRS, University of Bordeaux, INCIA, UMR 5287, 33000, Bordeaux, France
| | - Françoise Dellu-Hagedorn
- University of Bordeaux, INCIA, CNRS UMR 5287, PB. 31, 146 rue Léo Saignat, 33076, Bordeaux Cedex, France. .,CNRS, University of Bordeaux, INCIA, UMR 5287, 33000, Bordeaux, France.
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Ziemann U. Pharmaco-transcranial magnetic stimulation studies of motor excitability. HANDBOOK OF CLINICAL NEUROLOGY 2013; 116:387-397. [PMID: 24112911 DOI: 10.1016/b978-0-444-53497-2.00032-2] [Citation(s) in RCA: 69] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Application of a single dose of a central nervous system (CNS) active drug with a defined single mode of action has been proven useful to explore and characterize the pharmacophysiological properties of transcranial magnetic stimulation (TMS) measures of motor cortical and corticospinal excitability in humans. With this pharmaco-TMS approach, it was demonstrated that different TMS measures reflect axon excitability (motor threshold), or inhibitory (cortical silent period, short-interval intracortical inhibition, long-interval intracortical inhibition, short-latency afferent inhibition) or excitatory synaptic excitability (motor evoked potential amplitude, intracortical facilitation, short-interval intracortical facilitation) of distinct neuronal elements in the CNS. Pharmaco-TMS has opened an exciting window into human cortical physiology. The array of pharmacophysiologically well defined TMS measures is now used by neurologists, psychiatrists, and clinical neurophysiologists for diagnosis or treatment monitoring in neuropsychiatric disease. This chapter reviews systematically the TMS measures of motor cortical and corticospinal excitability from the perspective of pharmacophysiological characterization. For example, it is demonstrated that blockers of voltage-gated sodium channels specifically increase motor threshold but do not alter other TMS measures of excitability, whereas positive modulators at γ-butyric acid (GABA) type A receptors, such as benzodiazepines, enhance short-interval intracortical inhibition and depress motor evoked potential amplitude but have no effect on motor threshold.
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Affiliation(s)
- Ulf Ziemann
- Department of Neurology and Stroke, Hertie Institute for Clinical Brain Research, Eberhard-Karls University Tübingen, Tübingen, Germany.
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23
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Hodzhev Y, Yordanova J, Diruf M, Kratz O, Moll GH, Kolev V, Heinrich H. Methylphenidate (MPH) promotes visual cortical activation in healthy adults in a cued visuomotor task. J Neural Transm (Vienna) 2012; 119:1455-64. [DOI: 10.1007/s00702-012-0799-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2012] [Accepted: 03/18/2012] [Indexed: 10/28/2022]
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Schneider MKF, Retz W, Gougleris G, Verhoeven WMA, Tulen JHM, Rösler M. Effects of long-acting methylphenidate in adults with attention deficit hyperactivity disorder: a study with paired-pulse transcranial magnetic stimulation. Neuropsychobiology 2012; 64:195-201. [PMID: 21912187 DOI: 10.1159/000326693] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/15/2010] [Accepted: 02/21/2011] [Indexed: 11/19/2022]
Abstract
BACKGROUND Methylphenidate improves attention deficits, hyperactivity and impulsivity in attention deficit hyperactivity disorder (ADHD). Recent investigations into motor cortex excitability with paired-pulse transcranial magnetic stimulation (ppTMS) technique have shown inhibition deficits in ADHD which correlate with clinical symptomatology. Therefore, we investigated the neurophysiological effects of long-acting methylphenidate (LA-Mph) with the ppTMS technique in adult patients with ADHD. METHODS Thirteen right-handed adult ADHD patients who were first diagnosed with ADHD were included in this ppTMS study. Measurements took place before and during treatment with LA-Mph (30-54 mg/day). Statistical analyses were performed to investigate treatment effects and correlations with clinical symptomatology. RESULTS LA-Mph significantly decreased the relative short intracortical motor inhibition (SICI) magnetically evoked potential (MEP) amplitude at 3-ms interstimulus interval (conditioned/unconditioned MEP amplitude: 0.83 ± 0.76 drug-free vs. 0.29 ± 0.19 with LA-Mph; p=0.020). The relative intracortical facilitation MEP amplitude at 11 ms interstimulus interval (conditioned/unconditioned MEP amplitude: 1.51 ± 0.92 drug-free vs. 1.79 ± 0.95 with LA-Mph) was not significantly increased. The reduced relative SICI MEP amplitude with LA-Mph correlated significantly with the improvement of the psychopathological ADHD self-rating total scores (p=0.046). CONCLUSION These results show that in adult patients with ADHD, LA-Mph significantly improves motor disinhibition and might have differential stabilizing effects on motor hyperexcitability.
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Affiliation(s)
- Marc K F Schneider
- Institute for Forensic Psychiatry, University of the Saarland, Homburg, Germany.
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25
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Hoegl T, Heinrich H, Albrecht B, Diruf M, Moll GH, Kratz O. Interplay of neuronal processes during response inhibition: results from a combined event-related potentials (ERPs)/transcranial magnetic stimulation (TMS) study on methylphenidate. Int J Psychophysiol 2011; 81:99-106. [PMID: 21620906 DOI: 10.1016/j.ijpsycho.2011.05.004] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2011] [Revised: 05/03/2011] [Accepted: 05/09/2011] [Indexed: 01/03/2023]
Abstract
The neuronal processes underlying response inhibition are often studied using either event-related potentials (ERPs) or by applying transcranial magnetic stimulation (TMS) to investigate excitatory and inhibitory processes in the motor system. We performed a more refined analysis of response inhibition by combining both approaches with the aim of identifying an interplay between ERPs and TMS parameters. During a go/nogo task, motor system excitability was measured using TMS single and double pulses and brain electrical activity was recorded in healthy adults (n=14). Each participant completed two testing sessions, once on placebo and once on methylphenidate (double-blind, crossover design). Studying the effects of methylphenidate served as an example application for this combined approach. Developing regression models, inhibition-related TMS measures (e.g., short intracortical inhibition) and the contingent negative variation explained about 85% of the variance of the nogo-P3 under both MPH and placebo medication. The smaller the inhibitory effect in the motor system, the more terminal response control was required and the more resources were allocated for the evaluation of the inhibitory process, respectively, as indicated by a larger P3. Thus, an interplay between processes in the motor system (cortex) and control processes with sources in the prefrontal cortex and the anterior cingulate cortex (ACC) may take place, acting complementarily to facilitate a correct nogo-response. While ERPs rather represent initiation and monitoring of inhibitory processes and response control, motor inhibition may be best analyzed using TMS. A combined ERP/TMS analysis may allow for the development of distinct models concerning the interplay of processes involved in response inhibition.
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Affiliation(s)
- Thomas Hoegl
- Dept. of Child and Adolescent Mental Health, University of Erlangen-Nürnberg, Schwabachanlage 6+10, 91054 Erlangen, Germany.
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GIT1 is associated with ADHD in humans and ADHD-like behaviors in mice. Nat Med 2011; 17:566-72. [PMID: 21499268 DOI: 10.1038/nm.2330] [Citation(s) in RCA: 110] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2010] [Accepted: 02/11/2011] [Indexed: 12/19/2022]
Abstract
Attention deficit hyperactivity disorder (ADHD) is a psychiatric disorder that affects ~5% of school-aged children; however, the mechanisms underlying ADHD remain largely unclear. Here we report a previously unidentified association between G protein-coupled receptor kinase-interacting protein-1 (GIT1) and ADHD in humans. An intronic single-nucleotide polymorphism in GIT1, the minor allele of which causes reduced GIT1 expression, shows a strong association with ADHD susceptibility in humans. Git1-deficient mice show ADHD-like phenotypes, with traits including hyperactivity, enhanced electroencephalogram theta rhythms and impaired learning and memory. Hyperactivity in Git1(-/-) mice is reversed by amphetamine and methylphenidate, psychostimulants commonly used to treat ADHD. In addition, amphetamine normalizes enhanced theta rhythms and impaired memory. GIT1 deficiency in mice leads to decreases in ras-related C3 botulinum toxin substrate-1 (RAC1) signaling and inhibitory presynaptic input; furthermore, it shifts the neuronal excitation-inhibition balance in postsynaptic neurons toward excitation. Our study identifies a previously unknown involvement of GIT1 in human ADHD and shows that GIT1 deficiency in mice causes psychostimulant-responsive ADHD-like phenotypes.
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Lapitska N, Gosseries O, Delvaux V, Overgaard M, Nielsen F, Maertens de Noordhout A, Moonen G, Laureys S. Transcranial magnetic stimulation in disorders of consciousness. Rev Neurosci 2010; 20:235-50. [PMID: 20157993 DOI: 10.1515/revneuro.2009.20.3-4.235] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
We have reviewed the literature on transcranial magnetic stimulation studies in patients with brain death, coma, vegetative, minimally conscious, and locked-in states. Transcranial magnetic stimulation permits non-invasive study of brain excitability and may extend our understanding of the underlying mechanisms of these disorders. However, use of this technique in severe brain damage remains methodologically ill-defined and must be further validated prior to clinical application in these challenging patients.
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Affiliation(s)
- Natallia Lapitska
- Coma Science Group, Cyclotron Research Centre and Neurology Department, University of Liège, Liège, Belgium
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Modulation of motorcortical excitability by methylphenidate in adult voluntary test persons performing a go/nogo task. J Neural Transm (Vienna) 2009; 117:249-58. [PMID: 20012110 DOI: 10.1007/s00702-009-0349-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2009] [Accepted: 11/23/2009] [Indexed: 10/20/2022]
Abstract
This study investigated the interaction between motorcortical excitability (short interval cortical inhibition, intracortical facilitation and long interval cortical inhibition), different requirement conditions [choice reaction test (CRT), attention/go/nogo], and their pharmacological modulation by methylphenidate (MPH) in normal healthy adults (n = 31) using a transcranial magnetic stimulation paradigm. MPH was administered in a dosage of 1 mg/kg body weight, maximum 60 mg. Additionally, serum level and clearance of MPH were controlled. The statistical analysis of variance revealed a significant three-way interaction of 2 (MPH) x 3 (CRT) x 6 (ISI) predicting motor evoked potential amplitudes (P = 0.032, MPH none and full dose, n = 31). In order to compare effects of dosage an additional between-subjects factor (half vs. full MPH dose) was introduced. None of the interactions involving this between-subject factor reached statistical significance. Exploring interactions with MPH only, a 3 (MPH none, half and full dose) x 3 (CRT) x 6 (ISI) analysis of variance revealed significant two-way interactions for MPH x ISI (P = 0.040) and condition x ISI (P < 0.001, n = 18). Effects observed for MPH were strongest on facilitatory processes, weaker for intracortical inhibition. In sum, MPH seems to interact via striato-thalamo-cortical pathways with original motorcortical processes (ISI), to a lesser extent with task-dependent or behavioral parameters (CRT).
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Easton N, Marshall FH, Marsden CA, Fone KCF. Mapping the central effects of methylphenidate in the rat using pharmacological MRI BOLD contrast. Neuropharmacology 2009; 57:653-64. [PMID: 19733553 DOI: 10.1016/j.neuropharm.2009.08.018] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2009] [Revised: 08/10/2009] [Accepted: 08/11/2009] [Indexed: 11/26/2022]
Abstract
Methylphenidate (Ritalin) is a selective dopamine reuptake inhibitor and an effective treatment for attention deficit hyperactivity disorder (ADHD) however the anatomical foci and neuronal circuits involved in these therapeutic benefits are unclear. This study determines the temporal pattern of brain regional activity change produced by systemic administration of a therapeutically relevant dose of methylphenidate in anaesthetised Sprague-Dawley rats using BOLD MRI and a 2.35T Bruker magnet. Following 60 min basal recording separate rats received saline (n = 9) or +/- methylphenidate hydrochloride (2 mg/kg, i.p., n = 9) and BOLD changes were recorded for 90 min using statistical parametric maps. Methylphenidate produced significant positive random BOLD effects in the nucleus accumbens, substantia nigra, entorhinal cortex and medial orbital cortex. Negative random BOLD effects were more widespread and intense, occurring in the motor and somatosensory cortices, caudate putamen, lateral globus pallidus and bed nucleus of the stria terminalis, without accompanying changes in blood pressure or respiratory rate. Methylphenidate-induced negative BOLD in the striatum, and other dopamine terminal areas, may reflect post-synaptic changes produced by blockade of the neuronal dopamine reuptake transporter. While increased positive BOLD in the medial orbital cortex may reflect altered dopamine and/or noradrenaline release indirectly altering striatal activity. The overall pattern of BOLD changes is comparable to that seen in previous studies using guanfacine, amphetamine and atomoxetine, and suggests that although these compounds operate through distinct pharmacological mechanisms the BOLD changes may represent a 'fingerprint pattern' predictive of therapeutic benefit in ADHD.
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Affiliation(s)
- Neil Easton
- School of Biomedical Sciences, Medical School, Institute of Neuroscience, University of Nottingham, Queen's Medical Centre, Nottingham NG7 2UH, UK
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Schaefers AT, Teuchert-Noodt G, Bagorda F, Brummelte S. Effect of postnatal methamphetamine trauma and adolescent methylphenidate treatment on adult hippocampal neurogenesis in gerbils. Eur J Pharmacol 2009; 616:86-90. [DOI: 10.1016/j.ejphar.2009.06.006] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2008] [Revised: 05/27/2009] [Accepted: 06/08/2009] [Indexed: 12/11/2022]
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Kratz O, Diruf MS, Studer P, Gierow W, Buchmann J, Moll GH, Heinrich H. Effects of methylphenidate on motor system excitability in a response inhibition task. BEHAVIORAL AND BRAIN FUNCTIONS : BBF 2009; 5:12. [PMID: 19250519 PMCID: PMC2661088 DOI: 10.1186/1744-9081-5-12] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/11/2008] [Accepted: 02/27/2009] [Indexed: 11/29/2022]
Abstract
BACKGROUND Motor system excitability is based on a complex interaction of excitatory and inhibitory processes, which in turn are modulated by internal (e.g., volitional inhibition) and external (e.g., drugs) factors. A well proven tool to investigate motor system excitability in vivo is the transcranial magnetic stimulation (TMS). In this study, we used TMS to investigate the effects of methylphenidate (MPH) on the temporal dynamics of motor system excitability during a go/nogo task. METHODS Using a double-blind, placebo-controlled, crossover design, 14 healthy adults (8 male, 6 female; aged 20-40 yrs) performed a spatial go/nogo task (S1-S2 paradigm) either under dl-methylphenidate (MPH, 20 mg) or placebo. TMS single and double-pulses (interstimulus interval: 3 ms) were delivered either at 120, 230 or 350 ms after the S2 stimulus (control, go and nogo trials). RESULTS At the performance level, faster reaction times and a trend towards less impulsivity errors under MPH vs. placebo were observed.In nogo trials, i.e., when a prepared response had to be inhibited, motor evoked potentials (MEPs) had a smaller amplitude at an interval of 230 ms compared to 120 and 350 ms. The short-interval intracortical inhibition (SICI) increased over time.Under MPH, SICI in nogo trials was larger compared to placebo. With the interval between S2 and the TMS-pulse increasing, MEP amplitudes increased under MPH in nogo trials but an early inhibitory effect (at 120 ms) could also be observed. CONCLUSION Our results show a distinct pattern of excitatory and inhibitory phenomena in a go/nogo task. MPH appears to significantly alter the dynamics of motor system excitability. Our findings suggest that a single dose of 20 mg MPH provides some fine-tuning of the motor system in healthy adults.
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Affiliation(s)
- Oliver Kratz
- Department of Child and Adolescent Psychiatry, University of Erlangen-Nürnberg, Schwabachanlage 6, 91054 Erlangen, Germany
| | - Martin S Diruf
- Department of Child and Adolescent Psychiatry, University of Erlangen-Nürnberg, Schwabachanlage 6, 91054 Erlangen, Germany
| | - Petra Studer
- Department of Child and Adolescent Psychiatry, University of Erlangen-Nürnberg, Schwabachanlage 6, 91054 Erlangen, Germany
| | - Wolfgang Gierow
- Department of Child and Adolescence Psychiatry and Neurology, Center of Nerve Diseases, University of Rostock, Gehlsheimer Strasse 20, 18147 Rostock, Germany
| | - Johannes Buchmann
- Department of Child and Adolescence Psychiatry and Neurology, Center of Nerve Diseases, University of Rostock, Gehlsheimer Strasse 20, 18147 Rostock, Germany
| | - Gunther H Moll
- Department of Child and Adolescent Psychiatry, University of Erlangen-Nürnberg, Schwabachanlage 6, 91054 Erlangen, Germany
| | - Hartmut Heinrich
- Department of Child and Adolescent Psychiatry, University of Erlangen-Nürnberg, Schwabachanlage 6, 91054 Erlangen, Germany
- Heckscher-Klinikum München, Deisenhofener Strasse 28, 81539 München, Germany
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Barnow S, Völker KA, Möller B, Freyberger HJ, Spitzer C, Grabe HJ, Daskalakis ZJ. Neurophysiological correlates of borderline personality disorder: a transcranial magnetic stimulation study. Biol Psychiatry 2009; 65:313-8. [PMID: 18823879 DOI: 10.1016/j.biopsych.2008.08.016] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/20/2008] [Revised: 07/19/2008] [Accepted: 08/19/2008] [Indexed: 01/18/2023]
Abstract
BACKGROUND Cortical inhibition deficits have been demonstrated in several disorders with deficits in impulsive control (e.g., attention-deficit/hyperactivity disorder [ADHD], tic disorder, Tourette syndrome) by using transcranial magnetic stimulation (TMS). With borderline personality disorder (BPD), we investigated another disorder associated with high impulsivity by TMS. We hypothesized that BPD patients display decreased cortical inhibition and/or increased cortical excitation as assessed with TMS. METHODS Different inhibitory and excitatory TMS parameters were investigated in 19 unmedicated female BPD patients and 19 healthy control subjects matched for sex, age, handedness, and body height. Additionally, the results were controlled for ADHD symptomatology. RESULTS A reduced cortical silent period (CSP) duration was found in BPD patients compared with healthy control subjects in the right cortex. Even after controlling for ADHD symptoms, this result remained significant. CONCLUSIONS These findings support an association between BPD and cortical inhibition deficits as indexed through TMS. The results are discussed considering basic neurobiological mechanisms that may explain our findings of decreased intracortical inhibition in BPD patients.
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Affiliation(s)
- Sven Barnow
- Department of Clinical Psychology and Psychotherapy, Ruprecht-Karls University of Heidelberg, Heidelberg, Germany.
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Effects of methylphenidate on the catecholaminergic system in attention-deficit/hyperactivity disorder. J Clin Psychopharmacol 2008; 28:S46-53. [PMID: 18480677 DOI: 10.1097/jcp.0b013e318173312f] [Citation(s) in RCA: 190] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Stimulants are part of the standard-of-care treatment for attention-deficit/hyperactivity disorder (ADHD). Methylphenidate, with a history of use spanning approximately 5 decades, is a first-line stimulant treatment for ADHD. Methylphenidate chiefly affects the prefrontal cortex and striatum, the mechanism of action being modulation of catecholaminergic tone. Methylphenidate treatment produces an increase in dopamine (DA) signaling through multiple actions, including blockade of the DA reuptake transporter and amplification of DA response duration, disinhibition of DA D2 autoreceptors and amplification of DA tone, and activation of D1 receptors on the postsynaptic neuron. The actions of methylphenidate may also be mediated by stimulation of the noradrenergic alpha2 receptor and DA D1 receptor in the cortex. The role of other neurotransmitters such as histamine, acetylcholine, serotonin, and alpha-agonists in modulating catecholamine pathophysiology in ADHD and ADHD treatment needs to be elucidated. Overall, the changes in catecholaminergic tone clinically manifest as improvements in attention deficit, distractibility, and motor hyperactivity in patients with ADHD.
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Hoeppner J, Wandschneider R, Neumeyer M, Gierow W, Haessler F, Herpertz SC, Buchmann J. Impaired transcallosally mediated motor inhibition in adults with attention-deficit/hyperactivity disorder is modulated by methylphenidate. J Neural Transm (Vienna) 2008; 115:777-85. [DOI: 10.1007/s00702-007-0008-1] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2007] [Accepted: 11/13/2007] [Indexed: 10/22/2022]
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Frye RE, Rotenberg A, Ousley M, Pascual-Leone A. Transcranial magnetic stimulation in child neurology: current and future directions. J Child Neurol 2008; 23:79-96. [PMID: 18056688 PMCID: PMC2539109 DOI: 10.1177/0883073807307972] [Citation(s) in RCA: 86] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Transcranial magnetic stimulation (TMS) is a method for focal brain stimulation based on the principle of electromagnetic induction, where small intracranial electric currents are generated by a powerful, rapidly changing extracranial magnetic field. Over the past 2 decades TMS has shown promise in the diagnosis, monitoring, and treatment of neurological and psychiatric disease in adults, but has been used on a more limited basis in children. We reviewed the literature to identify potential diagnostic and therapeutic applications of TMS in child neurology and also its safety in pediatrics. Although TMS has not been associated with any serious side effects in children and appears to be well tolerated, general safety guidelines should be established. The potential for applications of TMS in child neurology and psychiatry is significant. Given its excellent safety profile and possible therapeutic effect, this technique should develop as an important tool in pediatric neurology over the next decade.
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Affiliation(s)
- Richard E. Frye
- Department of Pediatrics, Division of Child Neurology, University of Texas Health Science Center at Houston
| | - Alexander Rotenberg
- Department of Neurology, Children's Hospital Boston, Boston, Massachusetts, Berenson-Allen Center for Noninvasive Brain Stimulation, Department of Neurology, Beth Israel Deaconess Medical Center, Boston, Massachusetts, Harvard Medical School, Boston, Massachusetts
| | | | - Alvaro Pascual-Leone
- Berenson-Allen Center for Noninvasive Brain Stimulation, Department of Neurology, Beth Israel Deaconess Medical Center, Boston, Massachusetts, Harvard Medical School, Boston, Massachusetts, Institut Guttmann de Neurorehabilitació, Universitat Autónoma de Barcelona, Spain
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Buchmann J, Gierow W, Weber S, Hoeppner J, Klauer T, Benecke R, Haessler F, Wolters A. Restoration of disturbed intracortical motor inhibition and facilitation in attention deficit hyperactivity disorder children by methylphenidate. Biol Psychiatry 2007; 62:963-9. [PMID: 17719015 DOI: 10.1016/j.biopsych.2007.05.010] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/16/2007] [Revised: 05/10/2007] [Accepted: 05/11/2007] [Indexed: 10/22/2022]
Abstract
BACKGROUND Previous investigations using transcranial magnetic stimulation (TMS) have shown that neural inhibitory motor circuits are disturbed in ADHD children. We sought to investigate the influence of methylphenidate (MPH) on inhibitory and facilitatory motor circuits of ADHD children with TMS paired pulse protocols using surplus long interval inter-stimulus intervals (ISI) not investigated so far. METHODS Motorcortical modulation was tested with TMS paired pulse protocols employing ISI of 3, 13, 50, 100, 200, and 300 msec in 18 ADHD children before and on treatment with MPH. Clinical improvement by MPH was measured by the Conners score. RESULTS Analysis of variance (ANOVA) revealed a significant three-way interaction "Group x Amplitude x ISI," p = .001. Subsequent two-factorial ANOVAs and t-tests showed group specific differences of motor evoked potential (MEP) amplitudes for inhibitory ISIs of 3 and 100 msec, and for facilitatory ISIs of 13 and 50 msec. Compared to controls, an adjustment of these parameters by MPH could be shown. On MPH, a significant bivariate correlation was found between the Conners score reduction and averaged MEP amplitude changes only for inhibitory ISIs (3 and 100 msec). CONCLUSIONS In ADHD children, MPH modulates disturbed facilitatory and inhibitory motor circuits, which for the latter is associated with clinical improvement.
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Affiliation(s)
- Johannes Buchmann
- Department of Child and Adolescence Psychiatry and Neurology, Center of Nerve Diseases, University of Rostock, Rostock, Germany.
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Gilbert DL, Zhang J, Lipps TD, Natarajan N, Brandyberry J, Wang Z, Sallee FR, Wassermann EM. Atomoxetine treatment of ADHD in Tourette syndrome: reduction in motor cortex inhibition correlates with clinical improvement. Clin Neurophysiol 2007; 118:1835-41. [PMID: 17588810 PMCID: PMC1978200 DOI: 10.1016/j.clinph.2007.05.065] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2007] [Revised: 05/01/2007] [Accepted: 05/18/2007] [Indexed: 11/15/2022]
Abstract
OBJECTIVE In children with attention deficit hyperactivity disorder (ADHD), clinical responses to the selective norepinephrine reuptake inhibitor atomoxetine (ATX) vary. We sought to determine in children with Tourette Syndrome (TS) whether clinical responses correlate with changes in short interval cortical inhibition (SICI). METHODS Fourteen children, ages 8-16, with ADHD and TS were treated open-label with ATX for one month. ADHD rating scale scores and SICI, measured with paired-pulse transcranial magnetic stimulation (pTMS), were assessed blindly and independently at treatment onset and one month later. RESULTS Eleven children, mean ADHD rating scale scores 31.8 (SD 8.2) at onset, completed the study. After one month, ADHDRS changes ranged from an increase of 4 points to a decrease (improvement) of 24 points (mean change -9.6, SD 9.1). The changes in ADHDRS scores correlated with reduction in SICI (r=.74, p=.010). CONCLUSIONS In children with TS, one month of atomoxetine treatment appears to induce correlated improvements in ADHD and, paradoxically, further reductions in cortical inhibition. SIGNIFICANCE PTMS-evoked SICI in ADHD with TS may be a biomarker of both deficiency and compensatory changes within cortical interneuronal systems. Effective atomoxetine treatment may augment compensatory processes and thereby reduce SICI.
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Affiliation(s)
- Donald L Gilbert
- Division of Neurology, Cincinnati Children's Hospital Medical Center, and The University of Cincinnati, Department of Neurology, School of Medicine, OH 45229-3039, USA.
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Tardy J, Pariente J, Leger A, Dechaumont-Palacin S, Gerdelat A, Guiraud V, Conchou F, Albucher JF, Marque P, Franceries X, Cognard C, Rascol O, Chollet F, Loubinoux I. Methylphenidate modulates cerebral post-stroke reorganization. Neuroimage 2006; 33:913-22. [PMID: 16978883 DOI: 10.1016/j.neuroimage.2006.07.014] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2006] [Revised: 07/25/2006] [Accepted: 07/25/2006] [Indexed: 11/17/2022] Open
Abstract
OBJECTIVE We hypothesized that a single dose of methylphenidate (MP) would modulate cerebral motor activation and behavior in patients having suffered a subcortical stroke. METHODS Eight men with a single stroke on the corticospinal tract resulting in a pure motor hemiparesia were included in a randomized, cross-over, double-blind, placebo-controlled study. Patients were first evaluated 17 days after stroke onset by validated neurological scales, motor tests and fMRI (flexion/extension of the digits) after 20 mg MP or placebo. Seven days later, the patients underwent the same protocol and received the drug they had not taken at the first evaluation. Each patient was his own control. RESULTS Placebo intake did not change performance. MP compared to placebo elicited a significant improvement in motor performance of the affected hand at the finger tapping test. MP induced: (1) a hyperactivation of the ipsilesional primary sensorimotor cortex including the motor hand and face areas and of the contralesional premotor cortex; (2) a hypoactivation of the ipsilesional anterior cingulum. Hyperactivation in the face motor area correlated positively with the improvement in performance. CONCLUSION We demonstrated that the reorganized network may efficiently be targeted by the drug and that the effect of MP might partly rely on an improvement in attention/effort through cingulum modulation.
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Affiliation(s)
- Jean Tardy
- INSERM U455, Pavillon Riser, Purpan Hospital, Toulouse, France.
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Jacob C, Lesch KP. The Wuerzburg Research Initiative on Adult Attention-Deficit/Hyperactivity Disorder (WURIN-AADHD): multi-layered evaluation of long-term course. Eur Arch Psychiatry Clin Neurosci 2006; 256 Suppl 1:i12-20. [PMID: 16977545 DOI: 10.1007/s00406-006-1002-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Although the neurobiological basis of the clinical entity of attention-deficit/hyperactivity disorder (ADHD) is evident, data from studies on pathomechanism-phenotype correlations are inconsistent. There are several obvious limitations of the DSM-IV diagnostic criteria to describe an adequate phenotype of adult ADHD. A dimensional model of neurobiologically based endophenotypes is therefore more likely to be compatible with the genetic model of quantitative trait loci. The primary goal of the Wuerzburg Research Initiative on Adult Attention-Deficit/Hyperactivity Disorder (WURIN-AADHD) is to test the validity of two endophenotypes, deficit in response inhibition and impairment of working memory, using various psychometric and neurobiological strategies of investigation in adult patients with ADHD. An additional objective is the investigation of the long-term course of adult ADHD. The conclusive description of valid endophenotypes of ADHD is an ongoing process that may result in a comprehensive neurobiological model for ADHD or its symptom dimensions integrating genetic, neural, cognitive, and behavioral mechanisms. This model will eventually facilitate description of complete causal connections occurring across the lifespan from early development to adulthood and is also likely to accelerate development of more specific and efficient therapeutic strategies in adult ADHD.
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Affiliation(s)
- Christian Jacob
- Department of Psychiatry and Psychotherapy, University of Wuerzburg, Fuechsleinstrasse 15, 97080, Wuerzburg, Germany
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40
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Modulation of transcallosally mediated motor inhibition in children with attention deficit hyperactivity disorder (ADHD) by medication with methylphenidate (MPH). Neurosci Lett 2006; 405:14-8. [DOI: 10.1016/j.neulet.2006.06.026] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2005] [Revised: 03/15/2006] [Accepted: 06/10/2006] [Indexed: 11/21/2022]
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Gilbert DL, Ridel KR, Sallee FR, Zhang J, Lipps TD, Wassermann EM. Comparison of the inhibitory and excitatory effects of ADHD medications methylphenidate and atomoxetine on motor cortex. Neuropsychopharmacology 2006; 31:442-9. [PMID: 16034446 DOI: 10.1038/sj.npp.1300806] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Stimulant and norepinephrine (NE) reuptake inhibitor medications have different effects at the neuronal level, but both reduce symptoms of attention deficit hyperactivity disorder (ADHD). To understand their common physiologic effects and thereby gain insight into the neurobiology of ADHD treatment, we compared the effects of the stimulant methylphenidate (MPH) and NE uptake inhibitor atomoxetine (ATX) on inhibitory and excitatory processes in human cortex. Nine healthy, right-handed adults were given a single, oral dose of 30 mg MPH and 60 mg ATX at visits separated by 1 week in a randomized, double-blind crossover trial. We used paired and single transcranial magnetic stimulation (TMS) of motor cortex to measure conditioned and unconditioned motor-evoked potential amplitudes at inhibitory (3 ms) and facilitatory (10 ms) interstimulus intervals (ISI) before and after drug administration. Data were analyzed with repeated measures, mixed model regression. We also analyzed our findings and the published literature with meta-analysis software to estimate treatment effects of stimulants and NE reuptake inhibitors on these TMS measures. There were no significant pretreatment differences or effects of treatment order. Both agents produced a significant increase in facilitation and a decrease in inhibition. Effects of ATX and MPH did not differ significantly. Pooled estimates from published studies show similar results for stimulants and NE reuptake inhibitors. In conclusion, in healthy adults, both stimulant and nonstimulant medications for ADHD decrease cortical inhibition and increase cortical facilitation. Cortical inhibition, shown previously to be abnormal in ADHD, may play a key role producing behavioral pathology.
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Affiliation(s)
- Donald L Gilbert
- Division of Neurology, Cincinnati Children's Hospital Medical Center, University of Cincinnati, OH 45229, USA.
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Grund T, Lehmann K, Bock N, Rothenberger A, Teuchert-Noodt G. Influence of methylphenidate on brain development--an update of recent animal experiments. Behav Brain Funct 2006; 2:2. [PMID: 16403217 PMCID: PMC1363724 DOI: 10.1186/1744-9081-2-2] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2005] [Accepted: 01/10/2006] [Indexed: 01/26/2023] Open
Abstract
Methylphenidate (MPH) is the most commonly used drug to treat attention deficit/hyperactivity disorder (ADHD) in children effectively and safely. In spite of its widespread application throughout one of the most plastic and sensitive phases of brain development, very little is known to date about its long-term effects on brain structure and function. Hence, this short review updates the influence of MPH on brain development, since recent human and animal studies suggest that MPH alters the dopaminergic system with long-term effects beyond the termination of treatment. Animal studies imply that the effects of MPH may depend on the neural responder system: Whereas structural and functional parameters are improved by MPH in animals with psychomotor impairments, they remain unaltered or get worse in healthy controls. While recent behavioural studies do not fully support such a differential effect of MPH in ADHD, the animal studies certainly prompt for further investigation of this issue. Furthermore, the abuse of MPH, when (rarely) intravenously applied, may even impair the maturation of dopaminergic fibres in subcortical brain areas. This argues for careful clinical assessment and diagnostics of ADHD symptomatology not only in conjunction with the prescription of MPH. Hence, one should be assured that MPH is only given to children with clear ADHD symptomatology leading to psychosocial impairment. The animal data suggest that under these conditions MPH is supportive for brain development and the related behaviour in children with ADHD.
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Affiliation(s)
- Thorsten Grund
- Department of Neuroanatomy, Faculty of Biology, University of Bielefeld, Universitätsstr. 25, D-33615 Bielefeld, Germany
| | - Konrad Lehmann
- Department of Neuroanatomy, Faculty of Biology, University of Bielefeld, Universitätsstr. 25, D-33615 Bielefeld, Germany
| | - Nathalie Bock
- Child and Adolescent Psychiatry, University of Göttingen, von-Siebold-Strasse 5, D-37075 Göttingen, Germany
| | - Aribert Rothenberger
- Child and Adolescent Psychiatry, University of Göttingen, von-Siebold-Strasse 5, D-37075 Göttingen, Germany
| | - Gertraud Teuchert-Noodt
- Department of Neuroanatomy, Faculty of Biology, University of Bielefeld, Universitätsstr. 25, D-33615 Bielefeld, Germany
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Sergeant J. EUNETHYDIS -- searching for valid aetiological candidates of Attention-Deficit Hyperactivity Disorder or Hyperkinetic Disorder. Eur Child Adolesc Psychiatry 2004; 13 Suppl 1:I43-9. [PMID: 15322956 DOI: 10.1007/s00787-004-1005-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
BACKGROUND To step up research in ADHD, exchange of ideas, working together on key theoretical models and cooperative studies are necessary. OBJECTIVE To report about a European approach with strong links to the rest of the world. METHOD European Network on Hyperkinetic Disorders (Eunethydis) studies of Attention -- Deficit Hyperactivity Disorder (ADHD) or Hyperkinetic Disorder (HKD) is briefly reviewed in the context of the international effort to discover the aetiology of the disorder. RESULTS There are promising neurobiological, neurophysiological and neuropsychological candidates to explain the nature of ADHD/HKD. CONCLUSION Eunethydis has shown to be a fruitful platform for ADHD research and has good resources for its further development.
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Affiliation(s)
- Joseph Sergeant
- Free University, Clinical Neuropsychology, De Boelelaan 1105, 1081 HV, Amsterdam, The Netherlands.
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Abstract
The application of a single dose of a CNS active drug with a well-defined mode of action on a neurotransmitter or neuromodulator system may be used for testing pharmaco-physiological properties of transcranial magnetic stimulation (TMS) measures of cortical excitability. Conversely, a physiologically well-defined single TMS measure of cortical excitability may be used as a biological marker of acute drug effects at the systems level of the cerebral cortex. An array of defined TMS measures may be used to study the pattern of effects of a drug with unknown or multiple modes of action. Acute drug effects may be rather different from chronic drug effects. These differences can also be studied by TMS measures. Finally, TMS or repetitive TMS by themselves may induce changes in endogenous neurotransmitters or neuromodulators. All these possible interactions are the focus of this in-depth review on TMS and drugs.
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Affiliation(s)
- Ulf Ziemann
- Motor Cortex Laboratory, Clinic of Neurology, Johann Wolfgang Goethe University Frankfurt, Schleusenweg 2-16, D-60528 Frankfurt am Main, Germany.
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Kemner C, Jonkman LM, Kenemans JL, Böcker KBE, Verbaten MN, Van Engeland H. Sources of auditory selective attention and the effects of methylphenidate in children with attention-deficit/hyperactivity disorder. Biol Psychiatry 2004; 55:776-8. [PMID: 15039009 DOI: 10.1016/j.biopsych.2003.12.007] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/09/2003] [Revised: 12/09/2003] [Accepted: 12/11/2003] [Indexed: 10/26/2022]
Abstract
BACKGROUND The aim of this study was to determine 1) whether abnormal auditory selective attention in children with attention-deficit/hyperactivity disorder (ADHD), as reflected in the processing negativity (PN) of the event-related potential, is related to impaired frontal functioning; and 2) how methylphenidate (MPh) affects attentional functioning in ADHD. METHODS Sources of electrical brain activity were estimated in healthy control children, in ADHD children without medication, and in children with ADHD during a placebo-controlled medication trial involving MPh. RESULTS The source models showed that the PN is generated in the auditory cortex. Children with ADHD showed less activity related to selective attention in this brain region. Administration of MPh resulted in more frontally located sources. CONCLUSIONS The results showed no evidence for an important role of the frontal cortex in abnormalities in selective attention in children with ADHD. Also, the data did not indicate that MPh normalizes brain activity in these children.
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Affiliation(s)
- Chantal Kemner
- Department of Child and Adolescent Psychiatry, University Medical Center Utrecht, The Netherlands
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Korchounov A, Ilić TV, Ziemann U. The α2-adrenergic agonist guanfacine reduces excitability of human motor cortex through disfacilitation and increase of inhibition. Clin Neurophysiol 2003; 114:1834-40. [PMID: 14499745 DOI: 10.1016/s1388-2457(03)00192-5] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
OBJECTIVE To test the acute effects of the alpha2-adrenoceptor agonist guanfacine (GFC) on motor excitability in intact humans. METHODS Eight healthy right-handed adults received a single oral dose of 2 mg of GFC. Motor cortex excitability was tested by focal transcranial magnetic stimulation of the hand area of the left motor cortex. Motor evoked potentials (MEP) were recorded from the right abductor pollicis brevis muscle. In addition, spinal and neuromuscular excitability were tested. All measures were obtained immediately before GFC intake (baseline), and 2, 6, and 24 h later. RESULTS GFC decreased the slope of the MEP intensity curve, increased paired-pulse short-interval intracortical inhibition, and decreased paired-pulse intracortical facilitation and I-wave facilitation. These effects were maximal at 2-6 h and returned to baseline at 24 h. Motor threshold, cortical silent period, and the measures of spinal (peripheral silent period, F waves) and neuromuscular excitability (maximum M wave) remained unaffected. CONCLUSIONS This is the first study on the effects of an anti-noradrenergic drug on human motor cortex excitability. GFC reduced cortical excitability by disfacilitation and increased inhibition. These findings support the idea that anti-noradrenergic drugs are detrimental for cortical plasticity and learning which are down-regulated by disfacilitation or increased inhibition.
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Affiliation(s)
- Alexei Korchounov
- Clinic of Neurology, Johann Wolfgang Goethe-University Frankfurt, Theodor-Stern-Kai 7, D-60590, Frankfurt, Germany
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Ziemann U. Chapter 23 Pharmacology of TMS. TRANSCRANIAL MAGNETIC STIMULATION AND TRANSCRANIAL DIRECT CURRENT STIMULATION, PROCEEDINGS OF THE 2ND INTERNATIONAL TRANSCRANIAL MAGNETIC STIMULATION (TMS) AND TRANSCRANIAL DIRECT CURRENT STIMULATION (TDCS) SYMPOSIUM 2003. [DOI: 10.1016/s1567-424x(09)70226-0] [Citation(s) in RCA: 92] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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