Student: Enock Boakye
Project Mentors: Dr. Rosalind Sadleir – SBHSE
Dr. James Abbas – SBHSE
Dr. Bradley Greger – SBHSE
YouTube Link: View the video link below before joining the zoom meeting
Zoom Link: https://asu.zoom.us/j/7674535758
Zoom meeting time: 10am – noon.
Abstract
Transcranial direct current stimulation is a promising non-invasive neuromodulatory technique used as a therapeutic tool for treating neurological disorders such as severe anxiety and depression. However, there are reservations about the variability and reliability of the effects of tDCS due to the lack of understanding of the mechanisms. At present, there exists little data that can explain this variability. The objective of this study is to assess both intra and intersubject variability and reproducibility of tDCS therapy by comparing measured current densities and electrical fields in simulations of tDCS in finite element (FE) models of the brain. The variability was analyzed quantitatively using a combination of structural MRI imaging and computational modeling. Anatomically accurate uniform and full conductivity models of the head containing eleven different segmented tissues were constructed from structural MRI images acquired at 1mm3 resolution of five different subjects with electrodes attached for multiple treatment sessions. The FE method was used to simulate and estimate the current densities and electric field in a region of interest in the head for all models using a single electrode montage (F3-F4). Measured electrical densities and electrical fields will be compared between multiple therapy sessions for the same subject and between different subjects to quantitatively predict the degree of variability between individual subjects and multiple session therapy for both the full models and the uniform models. Any degree of variability in the electrical densities and electrical field between inter subjects may be related to the difference in anatomical features of the subjects. Variability between intra-subject results may be related to a slight misplacement of electrodes. These effects will be included as explanatory variables in the analysis of tDCS dosimetry and efficacy determined using magnetic resonance electrical impedance tomography and functional magnetic resonance imaging studies.