title: Use of Computational Modeling to Inform tDCS Electrode Montages for the Promotion of Language Recovery in Post-stroke Aphasia.
abstract: BACKGROUND
  Although pilot trials of transcranial direct current stimulation (tDCS) in aphasia are encouraging, protocol optimization is needed. Notably, it has not yet been clarified which of the varied electrode montages investigated is the most effective in enhancing language recovery.
  
  
  OBJECTIVE
  To consider and contrast the predicted brain current flow patterns (electric field distribution) produced by varied 1×1 tDCS (1 anode, 1 cathode, 5 × 7 cm pad electrodes) montages used in aphasia clinical trials.
  
  
  METHODS
  A finite element model of the head of a single left frontal stroke patient was developed in order to study the pattern of the cortical EF magnitude and inward/outward radial EF under five different electrode montages: Anodal-tDCS (A-tDCS) over the left Wernicke's area (Montage A) and over the left Broca's area (Montage B); Cathodal tDCS (C-tDCS) over the right homologue of Wernicke's area (Montage C), and of Broca's area (Montage D), where for all montages A-D the "return" electrode was placed over the supraorbital contralateral forehead; bilateral stimulation with A-tDCS over the left Broca's and CtDCS over the right Broca's homologue (Montage E).
  
  
  RESULTS
  In all cases, the "return" electrode over the contralesional supraorbital forehead was not inert and influenced the current path through the entire brain. Montage B, although similar to montage D in focusing the current in the perilesional area, exerted the greatest effect over the left perilesional cortex, which was even stronger in montage E.
  
  
  CONCLUSIONS
  The position and influence of both electrodes must be considered in the design and interpretation of tDCS clinical trials for aphasia.
authors.affiliation: Department of Speech-Language Pathology & Audiology, Hunter College, City University of New York, USA.
authors.forename: Elizabeth E
authors.initials: EE
authors.lastname: Galletta
authors.affiliation: Laboratory of Electrophysiology for Translational NeuroScience, (LET'S)-ISTC-CNR, Department of Clinical Neuroscience, Fatebenefratelli Hospital, Isola Tiberina, 00186 Rome, Italy; Institute of Neurology, Department of Geriatrics, Neurosciences & Orthopaedics, Catholic University of Sacred Heart, Rome, Italy.
authors.forename: Andrea
authors.initials: A
authors.lastname: Cancelli
authors.affiliation: Laboratory of Electrophysiology for Translational NeuroScience, (LET'S)-ISTC-CNR, Department of Clinical Neuroscience, Fatebenefratelli Hospital, Isola Tiberina, 00186 Rome, Italy; Department of Neuroscience and Imaging, G. d'Annunzio University of Chieti-Pescara, Chieti, Italy.
authors.forename: Carlo
authors.initials: C
authors.lastname: Cottone
authors.affiliation: Neurodegeneration Laboratory, IRCSS San Raffaele Pisana, Italy; Department of Neuroimaging, IRCCS San Raffaele Pisana, Rome, Italy.
authors.forename: Ilaria
authors.initials: I
authors.lastname: Simonelli
authors.affiliation: Laboratory of Electrophysiology for Translational NeuroScience, (LET'S)-ISTC-CNR, Department of Clinical Neuroscience, Fatebenefratelli Hospital, Isola Tiberina, 00186 Rome, Italy; Department of Neuroimaging, IRCCS San Raffaele Pisana, Rome, Italy.
authors.forename: Franca
authors.initials: F
authors.lastname: Tecchio
authors.affiliation: Department of Biomedical Engineering, City College, City University of New York, USA.
authors.forename: Marom
authors.initials: M
authors.lastname: Bikson
authors.affiliation: Dipartimento di Studi Umanistici, Università Federico II, Napoli, Italy; IRCSS Fondazione Santa Lucia, Rome, Italy. Electronic address: paola.marangolo@gmail.com.
authors.forename: Paola
authors.initials: P
authors.lastname: Marangolo
mesh_terms: D000328:Adult; D001037:Aphasia / Q000150:complications* / Q000503:physiopathology / Q000534:rehabilitation*; D065711:Broca Area / Q000502:physiology; D003198:Computer Simulation; D004566:Electrodes; D006801:Humans; D007802:Language; D008297:Male; D020521:Stroke / Q000150:complications* / Q000503:physiopathology; D000071939:Stroke Rehabilitation; D065908:Transcranial Direct Current Stimulation / Q000379:methods*; D065813:Wernicke Area / Q000502:physiology
keywords: Aphasia; Language rehabilitation; Modeling; Neuromodulation; tDCS