Marta Parazzini1, Serena Fiocchi2, Ilaria Liorni3, Elena Rossi4, Filippo Cogiamanian5, Maurizio Vergari5, Alberto Priori5, Paolo Ravazzani2. 1. CNR Consiglio Nazionale delle Ricerche, Istituto di Elettronica e di Ingegneria dell'Informazione e delle Telecomunicazioni IEIIT, 20133 Milano, Italy. Electronic address: marta.parazzini@ieiit.cnr.it. 2. CNR Consiglio Nazionale delle Ricerche, Istituto di Elettronica e di Ingegneria dell'Informazione e delle Telecomunicazioni IEIIT, 20133 Milano, Italy. 3. CNR Consiglio Nazionale delle Ricerche, Istituto di Elettronica e di Ingegneria dell'Informazione e delle Telecomunicazioni IEIIT, 20133 Milano, Italy; Dipartimento di Elettronica, Informazione e Bioingegneria, Politecnico di Milano, 20133 Milano, Italy. 4. Dipartimento di Elettronica, Informazione e Bioingegneria, Politecnico di Milano, 20133 Milano, Italy; Dipartimento di Fisiopatologia Medico-Chirurgica e dei Trapianti, Università degli Studi di Milano, 20122 Milano, Italy. 5. Dipartimento di Fisiopatologia Medico-Chirurgica e dei Trapianti, Università degli Studi di Milano, 20122 Milano, Italy; Centro Clinico per la Neurostimolazione, le Neurotecnologie ed i Disordini del Movimento, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, 20122 Milano, Italy.
Abstract
OBJECTIVE: Non-invasive transcutaneous spinal direct current stimulation (tsDCS) induces changes in spinal cord function in humans. Nonetheless, the current density (J) spatial distributions generated by tsDCS are unknown. This work aimed to estimate the J distributions in the spinal cord during tsDCS. METHODS: Computational electromagnetics techniques were applied to realistic human models, based on high-resolution MRI of healthy volunteers (a 26-years-old female adult model "Ella"; a 14years-old male adolescent model "Louis"; an 11years old female adolescent model "Billie"). Three electrode montages were modeled. In all cases, the anode was always over the spinal process of the tenth thoracic vertebra and the cathode was placed: (A) above the right arm; (B) over the umbilicus; (C) over Cz. The injected current was 3mA. The electrodes were conductors within rectangular sponges. RESULTS: Despite inter-individual differences, the J tends to be primarily directed longitudinally along the spinal cord and cauda equina with the region of higher amplitude influenced by the reference electrode position; on transversal sections, the J amplitude distributions were quite uniform. CONCLUSIONS: Our modeling approach reveals that the J generated by tsDCS reaches the spinal cord, with a current spread also to the muscle on the back and the spinal nerve. SIGNIFICANCE: This study is a first step in better understanding the mechanisms underlying tsDCS.
OBJECTIVE: Non-invasive transcutaneous spinal direct current stimulation (tsDCS) induces changes in spinal cord function in humans. Nonetheless, the current density (J) spatial distributions generated by tsDCS are unknown. This work aimed to estimate the J distributions in the spinal cord during tsDCS. METHODS: Computational electromagnetics techniques were applied to realistic human models, based on high-resolution MRI of healthy volunteers (a 26-years-old female adult model "Ella"; a 14years-old male adolescent model "Louis"; an 11years old female adolescent model "Billie"). Three electrode montages were modeled. In all cases, the anode was always over the spinal process of the tenth thoracic vertebra and the cathode was placed: (A) above the right arm; (B) over the umbilicus; (C) over Cz. The injected current was 3mA. The electrodes were conductors within rectangular sponges. RESULTS: Despite inter-individual differences, the J tends to be primarily directed longitudinally along the spinal cord and cauda equina with the region of higher amplitude influenced by the reference electrode position; on transversal sections, the J amplitude distributions were quite uniform. CONCLUSIONS: Our modeling approach reveals that the J generated by tsDCS reaches the spinal cord, with a current spread also to the muscle on the back and the spinal nerve. SIGNIFICANCE: This study is a first step in better understanding the mechanisms underlying tsDCS.
Authors: A Antal; I Alekseichuk; M Bikson; J Brockmöller; A R Brunoni; R Chen; L G Cohen; G Dowthwaite; J Ellrich; A Flöel; F Fregni; M S George; R Hamilton; J Haueisen; C S Herrmann; F C Hummel; J P Lefaucheur; D Liebetanz; C K Loo; C D McCaig; C Miniussi; P C Miranda; V Moliadze; M A Nitsche; R Nowak; F Padberg; A Pascual-Leone; W Poppendieck; A Priori; S Rossi; P M Rossini; J Rothwell; M A Rueger; G Ruffini; K Schellhorn; H R Siebner; Y Ugawa; A Wexler; U Ziemann; M Hallett; W Paulus Journal: Clin Neurophysiol Date: 2017-06-19 Impact factor: 3.708
Authors: Oluwole O Awosika; Marco Sandrini; Rita Volochayev; Ryan M Thompson; Nathan Fishman; Tianxia Wu; Mary Kay Floeter; Mark Hallett; Leonardo G Cohen Journal: Brain Stimul Date: 2019-01-29 Impact factor: 8.955
Authors: A J Woods; A Antal; M Bikson; P S Boggio; A R Brunoni; P Celnik; L G Cohen; F Fregni; C S Herrmann; E S Kappenman; H Knotkova; D Liebetanz; C Miniussi; P C Miranda; W Paulus; A Priori; D Reato; C Stagg; N Wenderoth; M A Nitsche Journal: Clin Neurophysiol Date: 2015-11-22 Impact factor: 3.708