title: Effects of Low Frequency Prefrontal Repetitive Transcranial Magnetic Stimulation on the N2 Amplitude in a GoNogo Task.
abstract: During the last decade, repetitive transcranial magnetic stimulation (rTMS) of the prefrontal cortex has become established as a treatment for various mental diseases. The rational of prefrontal stimulation has been adapted from the mode of action known from rTMS using motor-evoked potentials though little is known about the precise effect of rTMS at prefrontal sites. The objective of the current study is to investigate the inhibitory effect of prefrontal 1 Hz rTMS by stimulating the generators of event-related potentials (ERP) which are located in the prefrontal cortex. Thus, 1 Hz rTMS was applied offline over the left dorsolateral prefrontal cortex (DLPFC) and the medial prefrontal cortex (MPFC) in 18 healthy subjects who subsequently underwent a GoNogo task. Both active conditions were compared to sham rTMS within a randomized and counterbalanced cross-over design in one day. ERPs were recorded during task performance and the N2 and the P3 were analysed. After 1 Hz rTMS of the left DLPFC (but not of the MPFC), an inhibitory effect on the N2 amplitude was observed, which was related to inhibitory control. In contrast, after 1 Hz rTMS of the MPFC (but not at the left DLPFC) a trend towards an increased P3 amplitude was found. There was no significant modulation of latencies and behavioural data. The results argue in favour of an inhibitory effect of 1 Hz rTMS on N2 amplitudes in a GoNogo task. Our findings suggest that rTMS may mildly modulate prefrontally generated ERP immediately after stimulation, even where behavioural effects are not measurable. Thus, combined rTMS-ERP approaches need to be further established in order to serve as paradigms in experimental neuroscience and clinical research.
authors.affiliation: Department of Psychiatry, Ludwig-Maximilians University, Munich, Germany ; Child Neuropsychology Section, Department of Child and Adolescent Psychiatry and Psychotherapy, University Hospital of the RWTH Aachen, Aachen, Germany.
authors.forename: Nicola
authors.initials: N
authors.lastname: Grossheinrich
authors.forename: Maren
authors.initials: M
authors.lastname: Reinl
authors.forename: Oliver
authors.initials: O
authors.lastname: Pogarell
authors.forename: Susanne
authors.initials: S
authors.lastname: Karch
authors.forename: Christoph
authors.initials: C
authors.lastname: Mulert
authors.forename: Monika
authors.initials: M
authors.lastname: Brueckl
authors.forename: Kristina
authors.initials: K
authors.lastname: Hennig-Fast
authors.forename: Anne
authors.initials: A
authors.lastname: Rau
authors.forename: Maria
authors.initials: M
authors.lastname: Epple
authors.forename: Ariane
authors.initials: A
authors.lastname: Hornig
authors.forename: Frank
authors.initials: F
authors.lastname: Padberg
mesh_terms: D000328:Adult; D018592:Cross-Over Studies; D004569:Electroencephalography; D019054:Evoked Potentials, Motor / Q000502:physiology*; D056344:Executive Function / Q000502:physiology; D005106:Exploratory Behavior; D005260:Female; D007839:Functional Laterality; D006801:Humans; D007266:Inhibition, Psychological; D008297:Male; D009043:Motor Activity / Q000502:physiology*; D009483:Neuropsychological Tests; D010551:Personality; D017397:Prefrontal Cortex / Q000502:physiology*; D011930:Reaction Time; D050781:Transcranial Magnetic Stimulation / Q000379:methods; D055815:Young Adult