Transcranial electrical neuromodulation based on the reciprocity principle

• Autores: Fernandez Corazza, Mariano; Turovets, Sergei; Luu, Phan; Anderson, Erik; Tucker, Don
• Año de publicación: 2016
• Idioma: inglés
• Tipo de recurso: artículo
• Materia: HIGH-DENSITY ELECTRODE ARRAYS; NON-INVASIVE NEUROMODULATION; RECIPROCITY PRINCIPLE; TRANSCRANIAL DIRECT CURRENT STIMULATION; TRANSCRANIAL ELECTRICAL STIMULATION
• Institución: Consejo Nacional de Investigaciones Científicas y Técnicas

A key challenge in multi-electrode transcranial electrical stimulation (TES) or transcranial direct current stimulation (tDCS) is to find a current injection pattern that delivers the necessary current density at a target and minimizes it in the rest of the head, which is mathematically modeled as an optimization problem. Such an optimization with the Least Squares (LS) or Linearly Constrained Minimum Variance (LCMV) algorithms is generally computationally expensive and requires multiple independent current sources. Based on the reciprocity principle in electroencephalography (EEG) and TES, it could be possible to find the optimal TES patterns quickly whenever the solution of the forward EEG problem is available for a brain region of interest. Here, we investigate the reciprocity principle as a guideline for finding optimal current injection patterns in TES that comply with safety constraints. We define four different trial cortical targets in a detailed seven-tissue finite element head model, and analyze the performance of the reciprocity family of TES methods in terms of electrode density, targeting error, focality, intensity, and directionality using the LS and LCMV solutions as the reference standards. It is found that the reciprocity algorithms show good performance comparable to the LCMV and LS solutions. Comparing the 128 and 256 electrode cases, we found that use of greater electrode density improves focality, directionality, and intensity parameters. The results show that reciprocity principle can be used to quickly determine optimal current injection patterns in TES and help to simplify TES protocols that are consistent with hardware and software availability and with safety constraints.
Fil: Fernandez Corazza, Mariano. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones en Electrónica, Control y Procesamiento de Señales. Universidad Nacional de La Plata. Instituto de Investigaciones en Electrónica, Control y Procesamiento de Señales; Argentina. University of Oregon; Estados Unidos
Fil: Turovets, Sergei. University of Oregon; Estados Unidos. Electrical Geodesics Inc.; Estados Unidos
Fil: Luu, Phan. University of Oregon; Estados Unidos. Electrical Geodesics Inc.; Estados Unidos
Fil: Anderson, Erik. Electrical Geodesics Inc.; Estados Unidos
Fil: Tucker, Don. University of Oregon; Estados Unidos. Electrical Geodesics Inc.; Estados Unidos