Research Lab Results
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Veit Stuphorn Laboratory
The Veit Stuphorn Laboratory studies the neurophysiological mechanisms that underlie decision making and self-control. We record the activity of single neurons in awake animals that are engaged in decision-making processes. This allows us to identify the types of signals that neurons in specific parts of the brain represent and the computations they carry out. We also study human subjects in the same tasks with the help of fMRI. These parallel experiments provide comparative information about decision processes in human and non-human primates. -
Lee Martin Laboratory
In the Lee Martin Laboratory, we are testing the hypothesis that selective vulnerability--the phenomenon in which only certain groups of neurons degenerate in adult onset neurological disorders like amyotrophic lateral sclerosis and Alzheimer's disease--is dictated by brain regional connectivity, mitochondrial function and oxidative stress. We believe it is mediated by excitotoxic cell death resulting from abnormalities in excitatory glutamatergic signal transduction pathways, including glutamate transporters and glutamate receptors as well as their downstream intracellular signaling molecules. We are also investigating the contribution of neuronal/glial apoptosis and necrosis as cell death pathways in animal (including transgenic mice) models of acute and progressive neurodegeneration. We use a variety of anatomical and molecular neurobiological approaches, including neuronal tract-tracing techniques, immunocytochemistry, immunoblotting, antipeptide antibody production, transmission electron microscopy and DNA analysis to determine the precise regional and cellular vulnerabilities and the synaptic and molecular mechanisms that result in selective neuronal degeneration. -
Michael Wolfgang Laboratory
The Wolfgang Laboratory is interested in understanding the metabolic properties of neurons and glia at a mechanistic level in situ. Some of the most interesting, enigmatic and understudied cells in metabolic biochemistry are those of the nervous system. Defects in these pathways can lead to devastating neurological disease. Conversely, altering the metabolic properties of the nervous system can have surprisingly beneficial effects on the progression of some diseases. However, the mechanisms of these interactions are largely unknown. We use biochemical and molecular genetic techniques to study the molecular mechanisms that the nervous system uses to sense and respond to metabolic cues. We seek to understand the neurometabolic regulation of behavior and physiology in obesity, diabetes and neurological disease. Current areas of study include deconstructing neurometabolic pathways to understand the biochemistry of the nervous system and how these metabolic pathways impact animal behavior and physiology, metabolic heterogeneity and the evolution of metabolic adaptation. -
Michael Kornberg Lab
Our laboratory conducts basic and translational research aimed at better understanding the pathogenesis of multiple sclerosis (MS) and the role of the immune system in CNS disease, particularly the processes that drive progressive disability such as neurodegeneration and remyelination failure. We currently have three parallel research programs: 1. Metabolism as a modulator of MS: We are studying how basic metabolic pathways regulate the immune system and how these pathways might be exploited to protect neurons and myelin-forming oligodendrocytes from injury. 2. Identifying pathways by which nitric oxide (NO) and other free radicals cause neuronal and axonal damage. Our lab is identifying specific signaling pathways initiated by NO and other free radicals that can be targeted by drugs to produce neuroprotection. 3. Modulating the innate immune system in MS: In collaboration with others at Johns Hopkins, we are studying ways to enhance the reparative functions of microglia while preventing maladaptive responses. This work has identified bryostatin-1 as a potential drug that may be re-purposed for this task. -
Machine Biointerface Lab
Dr. Fridman's research group invents and develops bioelectronics for Neuroengineering and Medical Instrumentation applications. We develop innovative medical technology and we also conduct the necessary biological studies to understand how the technology could be effective and safe for people. Our lab is currently focused on developing the ""Safe Direct Current Stimulation"" technology, or SDCS. Unlike the currently available commercial neural prosthetic devices, such as cochlear implants, pacemakers, or Parkinson's deep brain stimulators that can only excite neurons, SDCS can excite, inhibit, and even sensitize them to input. This new technology opens a door to a wide range of applications that we are currently exploring along with device development: e.g. peripheral nerve stimulation for suppressing neuropathic pain, vestibular nerve stimulation to correct balance disorders, vagal nerve stimulation to suppress an asthma attack, and a host of other neuroprosthetic applications. Medical Instrumentation MouthLab is a ""tricorder"" device that we invented here in the Machine Biointerface Lab. The device currently obtains all vital signs within 60s: Pulse rate, breathing rate, temperature, blood pressure, blood oxygen saturation, electrocardiogram, and FEV1 (lung function) measurement. Because the device is in the mouth, it has access to saliva and to breath and we are focused now on expanding its capability to obtaining measures of dehydration and biomarkers that could be indicative of a wide range of internal disorders ranging from stress to kidney failure and even lung cancer. -
The Mumm Lab
The research conducted in the Mumm Lab (Dept. of Ophthalmology, Wilmer Eye Institute) is focused on understanding how neural circuits are formed, how they function, and how they can be regenerated, to develop new therapies for retinal regeneration. Toward that end, we investigate the development, function, and regeneration of disease-relevant neurons and neural circuits responsible for vision. An emphasis is placed on translating what can be learned in regenerative model systems to develop novel therapies for stimulating dormant regenerative capacities in humans, Therefore, we apply what we learn from a naturally regenerative species, the zebrafish, toward the development of novel therapies for restoring visual function to patients. We place an emphasis on unique perspectives zebrafish afford to biological studies, such as in vivo time-lapse imaging of cellular behaviors and cell-cell interactions, and high-throughput chemical and genetic screening. We have pioneered several technologies to support this work including multicolor imaging of neural circuit formation, a selective cell ablation methodology, and a quantitative high-throughput phenotypic screening platform. Together, these approaches are providing novel insights into how the degeneration and regeneration of discrete retinal cell types is controlled. -
The Nauen Lab
Epilepsy affects 1-3% of the population and can have a profound impact on general health, employment and quality of life. Medial temporal lobe epilepsy (MTLE) develops in some patients following head injury or repeated febrile seizures. Those affected may first suffer spontaneous seizures many years after the initial insult, indicating that the neural circuit undergoes a slow pathologic remodeling over the interim. There are currently no methods of preventing the development of MTLE. It is our goal to better understand the process in order to slow, halt, and ultimately reverse it. Our laboratory draws on electrophysiology, molecular biology, and morphology to study the contribution of dysregulated neurogenesis and newborn neuron connectivity to the development of MTLE. We build on basic research in stem cell biology, hippocampal development, and synaptic plasticity. We work closely with colleagues in the Institute for Cell Engineering, Neurology, Neurosurgery, Biomedical Engineering, and Radiology. As physician neuropathologists our grounding is in tissue alterations underlying human neurologic disease; using human iPSC-derived neurons and surgical specimens we focus on the pathophysiological processes as they occur in patients. By understanding changes in cell populations and morphologies that affect the circuit, and identifying pathologic alterations in gene expression that lead to the cell-level abnormalities, we hope to find treatment targets that can prevent the remodeling and break the feedback loop of abnormal activity > circuit change > abnormal activity. -
Ted Dawson Laboratory
The Ted Dawson Laboratory uses genetic, cell biological and biochemical approaches to explore the pathogenesis of Parkinson's disease (PD) and other neurologic disorders. We also investigate several discrete mechanisms involved in cell death, including the role of nitric oxide as an endogenous messenger, the function of poly (ADP-ribose) polymerase-1 and apoptosis inducing factor in cell death, and how endogenous cell survival mechanisms protect neurons from death. -
Translational Neurobiology Laboratory
The goals of the Translational neurobiology Laboratory are to understand the pathogenesis and cell death pathways in neurodegenerative disorders to reveal potential therapeutic targets for pharmaceutical intervention; to investigate endogenous survival pathways and try to induce these pathways to restore full function or replace lost neurons; and to identify biomarkers to mark disease function or replace lost neurons; and to identify biomarkers to mark disease progression and evaluate therapeutics. Our research projects focus on models of Huntington's disease and Parkinson's disease. We use a combination of cell biology and transgenic animal models of these diseases. -
James Knierim Laboratory
Research in the James Knierim Laboratory attempts to understand the flow of information through the hippocampal formation and the computations performed by the various subfields of the hippocampus and its inputs from the entorhinal cortex. To address these issues, we use multi-electrode arrays to record the extracellular action potentials from scores of well-isolated hippocampal neurons in freely moving rats. These neurons, or ""place cells,"" are selectively active when the rat occupies restricted locations in its environment and help to form a cognitive map of the environment. The animal uses this map to navigate efficiently in its environment and to learn and remember important locations. These cells are thought to play a major role in the formation of episodic (autobiographical) memories. Place cells thus constitute a tremendous opportunity to investigate the mechanisms by which the brain transforms sensory input into an internal, cognitive representation of the world and then uses this representation as the framework that organizes and stores memories of past events.