RESEARCH

Current Activity in Industry

• Introduction to Root Cause Analysis

• Conditional Granger Causality for Root Cause Analysis in Networking

• Introduction to Graph Machine Learning in Networking

• Graph Neural Network based Anomaly Detection

Previous Research in Academia

Overarching goal of my research is to better understand the neural systems of individuals with traumatic brain injury (TBI). To achieve this goal, I utilize advanced neuroimaging techniques such as functional magnetic resonance imaging (fMRI), resting-state fMRI, and brain morphometry in conjunction with imaging data analytics including network analysis, statistical data analysis, and machine learning. TBI is an injury to the brain by external force, leading to disruptions in brain function. TBI is a substantial threat to public health in the U.S. In 2010, 2.5 million emergency room visits, hospitalizations, or deaths were associated with TBI in the U.S. People with TBIs often sustain impairments in cognitive and emotional functioning, impacting the abilities to maintain their daily life skills and their surrounding family members. With my expertise obtained during trainings in electrical engineering, neurotrauma, and cognitive neuroscience, I am currently pursuing the following areas of research.

Brain networks in traumatic brain injury

Since the most common type of TBI is diffuse axonal injury, assessing TBI in the perspective of brain network is advantageous over region-based approaches. Utilizing well established methodologies from studies in healthy individuals such as resting-state fMRI and graph theory, I characterize altered brain network following TBI in the context of cognitive functions. Particularly, I am interested in how TBI disrupts connectivity between brain networks as coordination among multiple brain networks is the key to successful performance of higher-order cognitive functions such as planning, reasoning, and decision making. Further, this line of research will be crucial as people with TBI frequently show deficits in these high-order cognitive functions.

Comorbidity in traumatic brain injury

People with TBI often have comorbid psychiatric conditions including depression, anxiety, and post-traumatic stress disorder (PTSD), and these comorbid psychiatric conditions worsen their quality of life. A TBI to individuals with history of psychiatric disorders also yields more frequent recurrence of the psychiatric conditions. At present, my primary research interests in this area include identifying neuroimaging biomarkers to tease apart depression from TBI and to further stratify subtypes of depressive symptoms among individuals with TBI. Additional efforts in this area also include elucidating the underlying neural circuitry of relieved depressive symptoms after treatments for depression in TBI. This line of research will further strengthen clinicians' efforts to implement more effective and individualized treatment plans for these individuals.

Cognitive rehabilitation for chronic traumatic brain injury

As 3~5 million people in the U.S. are living with a TBI-related disability and cognitive dysfunction is the hallmark symptom of TBI, the need for effective cognitive rehabilitation is increasing. Although empirical support for improvement in behavior after cognitive rehabilitation for TBI is growing, changes in the brain associated with cognitive rehabilitation for TBI is poorly characterized. Utilizing advanced neuroimaging techniques including resting-state fMRI and brain morphometry, my research aims to characterize changes in brain structure and function of people with TBI following cognitive rehabilitation. This line of research will eventually provide objective brain-based markers for healthier brain after rehabilitation with greater sensitivity and precision. Further efforts in this area of research include identifying brain-based predictors for training-induced changes in the brain and training outcomes. My efforts in this research will inform rehabilitation professionals prior to training of who will benefit most and who will not from the given rehabilitation program for TBI. Thus, my research will help improving the ability to provide precision medicine to people with chronic TBI in the context of cognitive rehabilitation.