Novel neuroimaging techniques to identify risk and prognoses for psychiatric and neurological disorders
Recent years have witnessed an explosion of interest in neuroimaging the human brain and in using it to predict brain-based disease. However, the field generally conceives of neuroimaging as revealing disease-specific activation areas or networks, rather than explicitly considering the forces that govern the brain networks’ development. The conceptual transition—from thinking of neuroimaging as providing a static feature to thinking of its ability to capture a dynamic process—is critical for probing how a disease first develops in the brain, as well as for asking why two individuals—with identical clinical diagnoses—might show markedly different prognoses over time.
Most diseases in the body are “dysregulatory,” which means that the negative feedback loops in the body that maintain homeostasis break down in various ways. Importantly, physiological systems often slowly degenerate for years or decades before onset of symptoms.Thus, the ability to identify subtle shifts in the dynamics of those feedback loops would permit treatment of illnesses before they become symptomatic; in the way, for instance, that a glucose tolerance test is currently able to identify pre-diabetes before a person shows any diabetic symptoms. Dr. Lilianne Mujica-Parodi, Associate Professor of Biomedical Engineering at Stony Brook University School of Medicine and Associate Neuroscientist at Massachusetts General Hospital and Harvard Medical School, is developing novel methods to identify subtle signs of dysregulation in the homeostatic control circuits that regulate different brain functions, so that we can identify risk, prognoses, and therefore ultimately more effective treatment, for developing psychiatric and neurological disorders. The ability to "see" dysregulation with the techniques that Dr. Mujica-Parodi and her team at the Laboratory of Computational Neurodiagnostics (LCNeuro) are developing, would have an enormous impact not only for pre-symptomatic diagnosis and treatment, but also for pharmaceutical development and studies of disease genetics.
Thus far, LCNeuro takes an approach almost completely unique throughout the world, in developing methods to use a single patient’s neuroimaging data to derive his or her own “personal computational brain model,” composed of control circuits (described mathematically as a system of coupled differential equations). The advantage of having such a model is that one can, in principle, then feed it any set of new inputs, and thus simulate how the brain’s current dynamical state will evolve over minutes, hours, months, and possibly even years and decades. In so doing, Dr. Mujica-Parodi’s aim is to not only diagnose individuals in their current state, but also to predict that individual’s disease trajectory. In highly interactive clinical settings, Dr. Mujica-Parodi has worked with physicians and patients with a wide range of psychiatric and neurological diseases, including paranoid schizophrenia, clinical anxiety, major depressive disorder, addiction, and epilepsy. In addition, she has worked with the military to develop neurodiagnostic methods designed to predict resilience to combat-related stress for Special Forces populations. Her applied, interdisciplinary research, spanning clinical research, basic neuroscience, engineering, physics, and mathematics, is largely influenced by her interest and background in theoretical physics. Unlike much medical research, which is focused upon working upon compartmentalized areas, Dr. Mujica-Parodi aims to identify critical pathways and dynamics whose perturbation can unify and explain a wide variety of brain-based signs and symptoms. Combining neuroscience with ultra-high field ultra-fast fMRI and taking analytic techniques from control systems engineering, dynamical systems, and chaos theory, Dr. Mujica-Parodi hopes to provide real-world practical applications that can potentially change the face of brain-based medicine.
Current research includes:
- Psychiatry: LCNeuro investigates how different types of homeostatic dysregulation of the brain’s prefrontal-limbic and reward circuits lead to schizophrenia, anxiety, depression, or addiction, with the aim of predicting risk for developing the disease or, once patients are symptomatic, predicting how quickly the disease resolves or degenerates.
- Neurology: Because the human brain consumes a disproportionately high amount of energy (~22%) per volume (2%), as compared to other organs, it is particularly vulnerable to changes in metabolism. Dietary increase in glycemic load over the past 100 years has led to a national epidemic of insulin resistance (Type 2 diabetes), which has been identified as increasing risk for later-life dementia by 45%. Integrating multi-scale computational modeling to identify emergent properties with respect to brain networks, LCNeuro is currently conducting human studies to understand how diet affects energy constraints at the level of mitochondria, and in turn how mitochondria affect the aging brain’s ability to operate efficiently in response to cognitive demands. Additional research looks at the impact of metabolic dysregulation on the development of seizures. Up to one third of epileptics will see seizure frequency reduce on a ketogenic diet, yet the underlying basis for the phenomenon is still unknown.
- Optimizing Healthy Performance: The same control systems engineering approaches that can be used to predict risk for disease can also be used to predict how the healthy brain may respond to extreme environments. As one example, Dr. Mujica-Parodi has worked closely with elite military organizations in order to develop individual neurodiagnostics designed to predict resilience to combat-related stress, as well as to predict how an individual will make decisions under stress.
- Developing Better Tools: Dr. Mujica-Parodi’s analytical approaches are optimized for a quality of neuroimaging data that is seldom achieved in today’s clinical, or even research, scanners. Thus, one area of intense focus for her laboratory has been not only on designing better algorithms for analyzing data, but in finding ways to acquire the highest-quality data or to develop methods to amplify signal from data obtained from technologies with mainstream clinical usage. Dr. Mujica-Parodi is also interested in applying her analytic approaches to other physiological signals, and thus designed instrumentation for continuously and noninvasively measuring blood glucose levels (GlucoREAD). GlucoREAD is designed to complement her investigation of how regulation of glucose affects the brain, but also has mainstream applications for self-monitoring by diabetics.
Bio
Dr. Lilianne R. Mujica-Parodi is Director of the Laboratory for Computational Neurodiagnostics, and Associate Professor in Stony Brook University's Department of Biomedical Engineering, with secondary appointments in Neuroscience, Neurology, and Psychiatry. She is also Associate Neuroscientist in the Department of Radiology at Massachusetts General Hospital and Lecturer at Harvard Medical School.
Dr. Mujica-Parodi received her undergraduate and graduate degrees from Georgetown University and Columbia University, respectively, studying mathematical logic and foundations of physics. After her Ph.D. (Niles G. Whiting Fellow), she completed a three-year NIH Training Fellowship on Schizophrenia Research at the New York State Psychiatric Institute. Dr. Mujica-Parodi was subsequently promoted to Assistant Professor of Clinical Neuroscience at Columbia's College of Physicians and Surgeons, where she performed research for two years until being recruited by Stony Brook University.
She is the recipient of the National Alliance for Research in Schizophrenia and Affective Disorders Young Investigator Award (Essel Investigator), the National Science Foundation’s Career Award, and the White House’s Presidential Early Career Award in Science and Engineering, the “highest honor bestowed by the United States government on outstanding scientists and engineers in the early stages of their independent research careers.” Dr. Mujica-Parodi‘s research interests focus on the application of control systems engineering and complex systems analysis to state-of-the-art techniques in neuroimaging, with neurodiagnostic applications to neurological and psychiatric disorders.
While in graduate school, Dr. Mujica-Parodi conducted very abstract research on quantum nonlocality for her Ph.D. Midway through her dissertation, a close friend developed paranoid schizophrenia and eventually committed suicide, which deeply affected her. In spite of the fact that she found her Ph.D. research stimulating and personally fulfilling, she gradually came to feel the need to apply herself to problems with immediate impact on the world around her.
The morning following her dissertation defense, Dr. Mujica-Parodi started at Columbia University's College of Physicians and Surgeons as part of a NIH training program in schizophrenia research. Coming from a background in theoretical physics, she found medicine in general, and psychiatry in particular, to be a significant culture shock. While theoretical physics generally tries to identify a set of key “first principles” from which one can derive a wide variety of phenomena, medical research tends to be composed of disparate cottage industries focused upon one tiny isolated aspect of a particular disease. In the years that have followed, Dr. Mujica-Parodi has worked on developing a new approach to brain-based functioning and disease that is based upon identifying key points of failure in circuit regulation that, depending upon how it breaks, can lead to a wide variety of signs and symptoms that cluster as different diagnoses. This approach has led to developing new ways of exploiting neuroimaging, by using it to identify subtle features of dysregulation that, over time, cause the brain to develop in different ways. The ultimate goal is to develop neurodiagnostics capable of detecting (and treating) mental illness before the individual ever becomes symptomatic. Just as a glucose-tolerance test can predict "pre-diabetes" before an individual ever shows diabetic symptoms, she is applying similar principles in developing neurodiagnostics, whether it be for addiction, psychosis, depression, or dementia.
Although she is conducting medical research in highly-applied patient-oriented settings, she finds herself using many of the basic theoretical principles that she used to study for her Ph.D. Now applying principles of chaos theory and others that are applicable to neuroimaging, Dr. Mujica-Parodi feels that she has “come full circle” as she continues to advance her research.
Outside of research, she enjoys playing chamber music (as pianist and violinist), painting, hiking, and skiing.
For more information, visit www.lcneuro.org
Publications
Awards
Chair, 2012-2014
National Panel to Assess International Research & Development in Neuroimaging
Presidential Early Career Award for Scientists and Engineers, 2011
White House, Washington DC
National Science Foundation Career Award, 2010
Brain and Behavior Research Foundation Young Investigator Award, 2000
Niles Whiting Dissertation Fellowship Award, 1998
Patents
Mujica-Parodi LR, Sitharaman B, Dedora D. “GlucoREAD (Reporter Enhanced Analyte Detection) Patch: a novel non-invasive continuous glucose sensor using near-infrared spectroscopy and an optical probe”. Full Patent Application. Filed 8/9/13.
Hate having your blood drawn? READ technology is designed to eliminate the need for blood tests, by measuring values for a wide variety of substances in blood using optical methods that involve shining light on the skin’s surface. GlucoREAD is the first iteration of this approach, optimized specifically for continuous glucose monitoring for diabetes and insulin resistance.
Mujica-Parodi LR, Strey HH, DeDora D. “Dynamic Phantom for fMRI”. Full Patent Application. Filed 5/29/15.
In order to develop neurodiagnostic protocols for clinical settings, it is first necessary to be able to rigorously calibrate scanners so that tests are highly reliable and accurate, regardless of where they are performed around the world. The Dynamic Phantom produces user-controlled signals that are read by the fMRI as if they came from a brain. By comparing known inputs with scanner-acquired outputs, it is then possible to establish reliability how brain signals are distorted by the scanner, and to develop signal processing techniques capable of recovering the original signal.