title: [Transcranial magnetic stimulation (TMS), inhibition processes and attention deficit/hyperactivity disorder (ADHD) - an overview].
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.
authors.affiliation: Kinder- u. Jugendabteilung für Psychische Gesundheit, Universitätsklinikum Erlangen.
authors.forename: Thomas
authors.initials: T
authors.lastname: Hoegl
authors.affiliation: Klinik für Psychiatrie, Psychosomatik und Psychotherapie des Kindes- und Jugendalters, J. W. Goethe Universitätsklinikum, <location>Frankfurt am Main</location>
authors.forename: Stephan
authors.initials: S
authors.lastname: Bender
authors.affiliation: Klinik für Psychiatrie, Neurologie, Psychosomatik und Psychotherapie im Kindes- und Jugendalter, Zentrum Nervenheilkunde, Universität Rostock.
authors.forename: Johannes
authors.initials: J
authors.lastname: Buchmann
authors.affiliation: Kinder- u. Jugendabteilung für Psychische Gesundheit, Universitätsklinikum Erlangen.
authors.forename: Oliver
authors.initials: O
authors.lastname: Kratz
authors.affiliation: Kinder- u. Jugendabteilung für Psychische Gesundheit, Universitätsklinikum Erlangen.
authors.forename: Gunther H
authors.initials: GH
authors.lastname: Moll
authors.affiliation: Kinder- u. Jugendabteilung für Psychische Gesundheit, Universitätsklinikum Erlangen Heckscher-Klinikum, <location>München</location>
authors.forename: Hartmut
authors.initials: H
authors.lastname: Heinrich
mesh_terms: D001289:Attention Deficit Disorder with Hyperactivity / Q000175:diagnosis / Q000503:physiopathology / Q000523:psychology / Q000628:therapy*; D001931:Brain Mapping; D002648:Child; D004298:Dopamine / Q000502:physiology; D019054:Evoked Potentials, Motor / Q000502:physiology; D007839:Functional Laterality / Q000502:physiology; D005858:Germany; D006801:Humans; D007395:Interneurons / Q000502:physiology; D009044:Motor Cortex / Q000503:physiopathology; D009433:Neural Inhibition / Q000502:physiology*; D011712:Pyramidal Tracts / Q000503:physiopathology; D050781:Transcranial Magnetic Stimulation; D057170:Translational Research, Biomedical
chemical_list: D004298:Dopamine
keywords: Aufmerksamkeitsdefizit-/Hyperaktivitätsstörung (ADHS); Inhibitionsmarker; Kompensation; Methylphenidat; TMS-N100; Transcranial magnetic stimulation (TMS); Transkranielle Magnetstimulation (TMS); attention deficit hyperactivity disorder (ADHD); intracortical inhibition; intrakortikale Inhibition; ipsilaterale Silent Period; methylphenidate; motorischer Kortex; neurophysiological markers