Department of Neurology, Norman Fixel Institute for Neurological Diseases, University of Florida

Role: Full-time postdoctoral fellow.

Projects:

• Neurophysiology to guide deep brain stimulation for Parkinson's disease

Lab Website -- Department of Biomedical Engineering, Scientific Computing & Imaging (SCI) Institute, University of Utah

Role: Full-time graduate research assistant and NSF Graduate Research Fellow.

Research Support:

• National Science Foundation (NSF) Graduate Research Fellowship Program (GRFP) [1747505] -- 2018-2021

• Scientific Computing & Imaging Institute Graduate Fellowship in Computational Systems Bioengineering -- 2016-2020

Projects:

• Deep Brain Stimulation (DBS) for Tourette Syndrome (TS): I collaborated with the International TS DBS Registry and Database, a multisite consortium of TS DBS researchers and clinicians, to curate a novel dataset comprised of neuroimaging, stimulation settings, and clinical outcomes for over 130 TS DBS patients. My goal was to identify predictors of symptom improvement, including the site of stimulation (Johnson et al, JNNP, 2019), the modulated structural networks (Johnson et al, Brain, 2020), and the modulated basal ganglia fiber pathways (Johnson et al, Biol Psychiatry: CNNI, 2020) using neuroimaging and computational models of DBS.

• Deep Brain Stimulation (DBS) for Depression: I generated computational models of the volume of tissue activated by DBS for patients who underwent DBS of the subcallosal cingulate cortex as part of a randomized clinical trial at the University of Calgary (Dr. Zelma Kiss, Dr. Rajamannar Ramasubbu). The goal of the project was to quantify fiber tract activation associated with improvement in depressive symptoms (Clark et al, 2020a).

Peer-Reviewed Publications:

1. Johnson KA, Duffley G, Foltynie T et al, Basal Ganglia Pathways Associated with Therapeutic Pallidal Deep Brain Stimulation for Tourette Syndrome, Biol Psychiatry: Cogn Neurosci Neuroimaging, 2020, DOI: 10.1016/j.bpsc.2020.11.005.

2. Johnson KA, Duffley G, Anderson DN et al, Structural Connectivity Predicts Clinical Outcomes of Deep Brain Stimulation for Tourette Syndrome, Brain, 2020, DOI: 10.1093/brain/awaa188.

3. Clark DL, Johnson KA, Butson CR, Lebel C, Gobbi D, Ramasubbu R, Kiss ZHT, Tract-based analysis of target engagement by subcallosal cingulate deep brain stimulation for treatment resistant depression, Brain Stimulation, 2020, vol. 13, iss. 4, pp. 1094-1101, DOI: 10.1016/j.brs.2020.03.006.

4. Johnson KA, Fletcher PT, Servello D, et al, Image-Based Analysis and Long-Term Clinical Outcomes of Deep Brain Stimulation for Tourette Syndrome: A Multisite Study, J Neurol Neurosurg Psychiatry, 2019, vol. 90, iss. 10, pp. 1078-1090, DOI: 10.1136/jnnp-2019-320379.

5. Athawale T, Johnson KA, Butson CR, Johnson CR, A statistical framework for quantification and visualisation of positional uncertainty in deep brain stimulation electrodes, Comput Methods Biomech Biomed Eng Imaging Vis, 2018, DOI: 10.1080/21681163.2018.1523750.

Division of Cardiovascular Medicine, University of Utah

Role: Part-time image processing research technician.

Projects:

• Performed segmentation of cardiac MR images for clinical procedures and research projects related to cardiac arrhythmias. Contributed to several clinical research projects using cardiac MRI to study the role of tissue remodeling in cardiac arrhythmias (Chelu et al 2018).

• Developed a method for calculating conduction velocity in cardiac tissue using intraoperative electrophysiological recordings (undergraduate thesis project).

Research Support:

• University of Utah Undergraduate Research Opportunities Program (UROP) -- 2013-2014

Peer-Reviewed Publications:

1. Chelu MG, King JB, Kholmovski EG, Ma J, Gal P, Marashly Q, AlJuaid MA, Kaur G, Silver MA, Johnson KA, Suksaranjit P, Wilson BD, Han FT, Elvan A, Marrouche NF, Atrial fibrosis by LGE-MRI and catheter ablation of atrial fibrillation: five years follow up data, J Am Heart Assoc, 2018, vol. 7, pp. e006313, DOI: 10.1161/JAHA.117.006313.