Gregory Molnar, Ph.D.
Kelly Ryberg, M.A., CCRP
Mo Chen, Ph.D.
Erin Larson, Ph.D.
Dr. Carey’s neuromodulation interests are in applying noninvasive transcranial magnetic stimulation (TMS) to people with stroke to improve the excitability of surviving motor neurons and thereby improve their recovery of hand movement.
I am a clinical neurologist specializing in movement disorders and a research physiologist specializing in control of voluntary movement. My long term goal is to combine the two roles fruitfully. I study pathophysiology of the extrapyramidal motor system with a particular focus on basal ganglia and Parkinson's disease and on deep brain stimulation. My research is with human subjects and I collaborate extensively with bioengineers, neurosurgeons, and neuropsychologists.
We are investigating image-guided transcranial application of focused ultrasound (tFUS) to neuromodulation. We have developed a unique paradigm for tFUS utilizing our dual-mode ultrasound array (DMUA) prototypes. DMUAs are capable of subtherapeutic or therapeutic of tFUS while providing real-time monitoring and localization of its interactions with brain tissue. Our DMUA prototypes have been shown to detect and localize both mechanical and thermal tFUS-tissue interactions with brain tissues in a rat model in vivo.
Dr. Engel's lab studies neuroplasticity in the human visual system. We use environmental manipulations, including augmented reality, to try to modulate function of the visual brain.
My lab studies the neurophysiological basis of cognitive factors such as attention and learning which are critical to behavioral performance. We employ neuromodulation and stimulation to understand, probe, and hopefully augment or mimic the effects of these factors. We use a variety of techniques including multi-electrode recordings, optical imaging, fMRI, computation, and psychophysics to characterize these factors, and their neural bases, in both behaving animals and humans.
Research interests in cortical plasticity and recovery from neurologic insult in both adult and pediatric populations. Her research encompasses the use of different forms of non-invasive brain stimulation (transcranial magnetic stimulation and transcranial Direct Current stimulation), in combination with behavioral training, for improved motor function. Current Teaching Responsibilities include Research, Pediatric Rehabilitation, and Professional Behaviors in Academia.
My current research focuses on the development and integration of 7T MRI and high-field neuroimaging data into deep brain stimulation (DBS) surgical navigation in particular and brain surgery in general. We are developing new structural/anatomical imaging which are combined with post processing image analysis schemes for the creation of a 3-dimensional anatomical model of the brain. This 3D model created by the 7T images allows us to literally ‘see’ the individual shape, size and orientation of the brain target area for DBS therapy.
My group is primarily interested in developing and refining neural interface technologies to improve the quality of life for people with movement disorders. Deep brain stimulation (DBS) is one such technology, which over the past twenty years has helped numerous patients with Parkinson’s disease, dystonia, and essential tremor reclaim control over their motor function. The therapy involves placing small electrodes in regions of the brain that exhibit pathological activity, which contributes to the movement disorder, and then stimulating those regions with continuous pulses of electricity. My lab focuses on understanding how the brain responds and adapts to such stimulation-based therapies from a combination of computational and experimental perspectives. The knowledge gained from these studies in turn provides us with a framework to develop, evaluate, and translate new approaches for improving patient outcome.
Suhasa Kodandaramaiah's research group is focused on engineering neurotechnologies that help better understand how computations that occur in the brain drive behavior. A critical challenge for modern neuroscience is to study neuronal computations across multiple spatial and temporal scales. Traditionally, technologies used to observe activities at one level do not scale to the next level without loss of signal fidelity or information. HIs laboratory is combining expertise in robotics, precision engineering, optics and microfabrication for engineering technologies that seek to bridge these experimental scales.
I am the head of a laboratory with a research focus on sensorimotor dysfunction in neurological diseases. We are actively engaged in developing new behavioral treatment options that can supplement or augment existing therapies. Currently we investigate how neuromodulation affects haptic perception in Parkinson's disease and how it changes voice quality for patients with a dystonic voice disorder called spasmodic dysphonia
We are using neuromodulation techniques to understand the role of the neurohormone orexin in energy balance. Our laboratory first developed the idea that orexin drives spontaneous physical activity (SPA) and non-exercise activity thermogenesis (NEAT); that it interacts with other neurotransmitters and brain sites in a network fashion; and that it has relevance to obesity: higher orexin signaling is associated with greater SPA and NEAT, the lean state and obesity resistance. Recently we have shown that orexin stimulation - either by direct receptor stimulation with orexin A injections in rats, or by DREADD [Designer Receptors Exclusively Activated by Designer Drugs] stimulation of orexin neurons in mice, prevents diet-induced adiposity and weight gain. This, coupled with our use of optogenetics to understand effects of acute simulation and inhibition of orexin neurons, and the recent development of the CAV2-Cre virus, which transfers Cre recombinase retrogradely between neurons, allows us to begin the study of orexin thermogenic pathways relevant to obesity.
Neuronal networks, diversity, and specificity of function are important to both physiological processes and neurological disorders, including epilepsy. My laboratory seeks to improve our understanding of how cells interact within a network, how networks interact with each other, and the physiological roles of neuronal populations. In this regard, key questions remain in epilepsy research, including what are the principal networks, conditions, and cell types involved in initiating, sustaining, propagating, terminating, and potentially suppressing, seizures. By improving our understanding of these, we improve the prospects of someday reaching the goal of no seizures, no side effects, for all epilepsy patients. My lab uses rodent models of neurological disorders, including temporal lobe epilepsy, and techniques including electrophysiology, optogenetics, immunocytochemistry, transgenic animals, and behavioral experiments to address these fundamental questions.
Vipin Kumar is currently William Norris Professor and Head of the Computer Science and Engineering Department at the University of Minnesota. Kumar's current research interests include data mining, high-performance computing, and their applications in Neuroscience, Climate/Ecosystems and Biomedical domains. In the context of human neuroscience, the focus is on functional connectivity and its dynamics in healthy, disease, and post-treatment conditions. Functional connectivity analysis techniques developed in his group are highly suited for assessing the effectiveness of neuromodulation in treating mental disorders.
My laboratory examines cognitive control, working memory and executive functioning and decision-making. We are using neuroimaging to decode brain regions involved in these processes, and transcranial stimulation to examine and promote plasticity in these processes. This work extends into psychopathology, such as understanding how brain stimulation can promote cognitive remediation in people with schizophrenia or predicting decisions related to addiction risk.
My laboratory is studying how the neuroactive substance, dopamine, influences identifiable neural circuits to choreograph specific locomotor programs, and impacts decision-making processes. To address such issues, at the level of single neurons and their interconnections, we utilize experimentally-tractable invertebrate preparations. Such systems have also proven beneficial for the testing of cutting-edge technologies for brain modulation. Currently, we are designing, manufacturing, and testing novel micro devices for the dual recording of electrical and chemical signals. We are also examining the cellular mechanisms underlying ultrasound neuromodulation.
The goal of my research is to utilize novel DBS paradigms based on the generation of rotating fields by amplitude and frequency modulated pulses, for efficient low energy modulation of thalamic – cortical pathways. The general objective is to optimize DBS pulse shapes to generate excitation of selective neuronal populations. The work on animal models is critical for the translation of more efficient and safer DBS strategies to humans. Development of novel efficient schemes which allow for flexible and selective excitability of cell’s and axonal populations is critical. The detection of network level activity leaded to a breakthrough development of resting state functional MRI (rsfMRI) methodologies. Our preliminary studies demonstrate that strikingly different functional connectivity outcomes can be robustly measured by fMRI in rest and activated conditions upon different DBS paradigms, thus substantiating the rationale for this project.
Dr. Greg Molnar has 20 years of experience as a medical device innovator and expertise in neuromodulation research. Dr. Molnar is an Associate Professor in the Department of Neurology at the University of Minnesota (UMN) and provides leadership to the clinical and preclinical research across the Deep Brain Stimulation (DBS) Research Program. Greg is a Principal Investigator in the newly established UMN NIH Udall Center of Excellence for Parkinson's Disease and Co-Investigator on several other NIH and Industry grants. Dr. Molnar trained as a clinical neuroscientist at the University of Toronto, where his research focused on the mechanism of action of DBS and neuromodulation to treat chronic pain and movement disorders. He also used several non-invasive neuromodulation techniques.
Dr Nahas scientific interests lie in translational research of mood dysregulation and depressive disorders. His unique expertise is in functional neuroimaging and brain stimulation across various modalities [Transcranial Magnetic Stimulation (TMS), Vagus Nerve Stimulation (VNS), Epidural prefrontal Cortical Stimulation (EpCS), Deep Brain Stimulation (DBS), Electroconvulsive Therapy (ECT) and Focally Electrically Administered Seizure Therapy (FEAST)]. He has also conducted basic research and collaborated on health economic studies. He received funding from various sources, notably the National Institute of Mental Health, National Alliance for Research in Schizophrenia and Depression (NARSAD) and the Hope for Depression Research Foundation (HDRF).
In the Center for Applied and Translational Sensory Science (CATSS) lab, we are working on the development and refinement of sensory aids for sensory loss. Most of Dr. Nelson’s work is focused on auditory perception and device evaluation. Specifically, we believe that auditory sensory aids (hearing aids and cochlear implants) have progressed to the point where speech intelligibility is conveyed quite successfully, at least for understanding in quiet environments. We believe the next stage is improving the sound quality and ease of listening for users of these sensory aids. Improving these abilities would ensure that the central auditory system has acclimated to the new inputs, and is processing them as natural acoustic information. Visual and vestibular implants are in earlier stages of development, but show promise to improve sensory input to the brain to improve quality of life for millions of Americans.
Our laboratory studies the role of the autonomic nervous system in the pathogenesis of cardiovascular and metabolic diseases with an emphasis on hypertension. We are particularly interested in how nerves to (efferent sympathetic) and from (visceral afferent) the kidney regulate renal and cardiovascular function. At the present time we are developing novel approaches to modulate renal nerves, using optogenetics.
Dr. Park will use his background in biology, medicine, and electrical engineering to work with other university departments, such as neurology and medical bioengineering, to create new devices that increase therapeutic options for patients with brain conditions. His research interests include: brain structure, neuromodulation/deep brain stimulation, and medical device innovation.
I am interested in the neural mechanisms associated with the processing of information that leads to the production of movements. For this purpose, we combine psychophysical and neurophysiological approaches. The current projects concern (1) how the brain deals with uncertainty during motor planning; (2) the decoding of brain signals for brain-machine interface applications.
My main research objective is to use theory, neurophysiology, and computational modeling to understand how the brain drives behavior. My lab combines multi-electrode neural ensemble recordings from awake, behaving animals with complex computational analysis techniques that enable measurement of neural dynamics at very fast time scales (e.g. msec). Furthering the understanding of the neural mechanisms that underlie decision-making allows us to modulate those decision-making processes, behaviorally as well as neurally.
Brain disorders and mental illness represent a tremendous social and economic burden, with few effective treatments. The goal of our research is to identify the causes of brain conditions, and develop interventions to restore healthy function using synaptic plasticity and neuromodulation. We study the striatum, and important brain region for both simple and complex movements and cognitive functions. We examine the function of neural circuits formed by striatal synapses that connect specific sources and targets. Our multidisciplinary approach includes quantitative analysis of gene expression; genetic and molecular manipulations of neural circuits; measurement of synaptic function and plasticity using electrophysiology; and optogenetic stimulation of circuits in brain slices and behaving animals. Our current research focuses on autism spectrum disorders and drug addiction - two brain conditions that affect overlapping elements of striatal circuitry.
I came late to neuromodulation, having been trained as a neuro-oncologist with research interests in quantitative neuroimaging and computational anatomy. With the advent of deep brain stimulation (DBS) for the treatment of movement disorders in the 1990's I recognized an opportunity to transfer my computer skills and computational interests to programming the implanted pulse generators used for DBS. My clinical and research interests in DBS focus on the poorly-understood high-dimensional space created by the multiple parameters — active contacts, applied voltage, pulse width, constant current, and stimulation frequency — that are routinely selected to modulate DBS in individual patients.
Our group invents and applies protein engineering technologies to study how cells sense, integrate and exchange information, how pathologic changes in these processes relate to health and disease, and provide insights into new therapies. We are developing novel optogenetic reagents that allow us to systematically perturb specific ion channels and signaling receptors in a time- and amplitude-variant manner. We combine these molecular reagents into an experimental framework in which all families of ion channels and receptors can be independently controlled, and their contribution to diverse cellular signal transduction circuits investigated.
We study the therapeutic effect and efficacy of vagal nerve stimulation (VNS) therapy in experimental in-vivo animal models, aiming to assess the effects of VNS therapy on the functional and electrophysiological properties of the heart. We continuously record in-vivo ECG and blood pressure to characterize the effect of VNS on heart rate, blood pressure and arrythmias. We also perform ex-vivo optical mapping experiments in the isolated whole heart that allow us to study complex spatio-temporal organization of electrical activity encountered in the heart during normal and abnormal rhythms, and investigate the electrophysiological properties induced by VNS in both healthy and diseased hearts.
As a founding member of the neuromodulation team when I arrived at the University of Minnesota in 1996 I am playing a crucial role in managing the medical aspects related to Parkinson's disease as well as partaking in the Deep Brain Stimulation (DBS) surgical program consensus meetings that help select appropriate individuals for DBS surgery.
Dr. Ugurbil is the director of the Center for Magnetic Resonance Research (CMRR) where he leads a multi-investigator and multi-disciplinary research effort focused on imaging brain anatomy, function, and connectivity with magnetic resonance (MR) techniques, particularly at ultrahigh (7 Tesla and above) magnetic fields. These techniques are increasingly important in evaluating numerous aspects of neuromodulation, such as defining circuits involved, targets for neuromodulation, consequences of neuromodulation, etc.
Dr. Sophia Vinogradov studies the behavioral and neuroplastic effects of cognitive training on executive functioning, social cognition, and sensory processing in people with schizophrenia and other psychotic illnesses. She has begun to study how neuromodulation approaches can enhance the effects of cognitive training and increase the durability of training effects. Dr. Vinogradov is a co-investigator on a study of tDCS combined training targeting working memory and sensory processing, examining the impact on symptoms, cognition, and EEG function in individuals with schizophrenia. She is also beginning pilot work examining the effects of rTMS cognition delivered to medial prefrontal cortex plus training targeting social cognition on anhedonia and amotivation in psychosis.
Dr. Vitek directs a large interdisciplinary neuromodulation research program primarily centered on understanding the pathophysiology of movement disorders such as Parkinson's disease and dystonia as well as the mechanisms underlying the therapeutic effect of deep brain stimulation. Dr. Vitek serves as the principal investigator for both pre-clinical laboratory studies using animal models and clinical studies on human subjects/patients. Much of his work focuses on the ultimate translation of basic laboratory research discoveries into clinical treatment options for affected patients in order to reduce symptoms, minimize side effects and enhance function and quality of life. Dr. Vitek forms key collaborations with other experts in neurology as well as other disciplines such as neurosurgery, neuroscience, biomedical science, and radiology in addition to the medical industry to expedite and enhance new discoveries and their meaningful translation from “bench to bedside.
Zhi Yang is an Assistant Professor at the Department of Biomedical Engineering at the University of Minnesota. He is the PI of the NeuroElectronics Lab, working on new stimulation, recording, and signal processing device that can enable high channel counts and closed-loop neuromodulation in the brain and in peripheral/autonomic nerves.
Department of Biomedical Engineering
Mentor: Alexander Opitz, Ph.D.
Project: Studying the effects of inter-regional connectivity manipulation using model-driven, dual-site transcranial alternating current stimulation in humans
Dr. Alekseichuk’s research will investigate the simultaneous entrainment of brain rhythms in two distinct regions using transcranial electric stimulation, with the goal of developing new therapies for schizophrenia and ADHD.
Department of Mechanical Engineering
Mentor: Wei Chen, Ph.D.
Project: Development of a novel neural electrode for brain stimulation and recording in MRI – reduction of electrode heating and elimination of image artifacts
Cory Cruttenden’s innovative neural electrode will advance the study and application of electrical stimulation for the treatment of brain conditions using functional MRI.
Department of Neurosurgery
Mentor: Ann Parr, MD, PhD
Project: The optimization of epidural neuromodulation for spinal cord injury patients
Dr. Freeman’s project is to establish and investigate epidural spinal cord stimulation in paraplegic patients to facilitate volitional movement.
Department of Ophthalmology
Mentor: Sandra Rocio Montezuma, M.D.
Project: Mapping the electrically-elicited visual responses in blind patients implanted with
the Argus II retinal prosthesis
Dr. He's innovative research will provide a practical way to evaluate how the spatial information provided by retinal prostheses is used by blind patients, which in turn can improve the device performance.
Department of Psychiatry
Mentor: Kelvin Lim, M.D.
Project: Neurodynamics of knowledge-based decision making
Dr. Herman's project is aimed at developing new biomarkers for depression and other conditions characterized by dysfunction in decision making. This research will lead to new therapeutic targets for brain stimulation.
Department of Biomedical Engineering
Mentor: Hubert Lim, Ph.D.
Industry Partner: The Ultran Group, Anuj Bhardwaj
Project: Autonomic neuromodulation of the brain-spleen anti-inflammatory reflex: development of a wearable ultrasound stimulation and imaging device to treat rheumatoid arthritis
Claire Kaiser’s project aims to develop a wearable, noninvasive device for targeted ultrasound of neural pathways within the spleen combined with noninvasive electrical stimulation of the vagus nerve to treat rheumatoid arthritis.
Department of Neuroscience
Mentor: Patrick Rothwell, Ph.D.
Project: Pharmacological enhancement of optogenetic deep brain stimulation to correct autism-related brain dysfunction
Brian Trieu’s preclinical research aims to understand how impaired brain systems could be reversed in autism in order to develop new therapies to restore behavioral and cognitive processes.
Department of Neuroscience
Mentor: John Osborn, Ph.D.
Project: Investigating the function of renal glomerular sensory nerve fibers in sympathetic control of glomerular filtration
Neuromodulation of renal nerves may be a promising therapy for hypertension. A better understanding of the interactions between renal efferent and afferent nerves is needed to develop this therapy.