Our research is directed toward how the brain controls the movements of the eyes (including eye movements induced by head motion) using studies in normal human beings, patients and experimental animals. The focus is on mechanisms underlying adaptive ocular motor control. More specifically, what are mechanisms by which the brain learns to cope with the changes associated with normal development and aging as well as the damage associated with disease and trauma? How does the brain keep its eye movement reflexes properly calibrated? Our research strategy is to make accurate, quantitative measures of eye movements in response to precisely controlled stimuli and then use the analytical techniques of the control systems engineer to interpret the findings. Research areas: 1) learning and compensation for vestibular disturbances that occur either within the labyrinth or more centrally within the brain, 2) the mechanisms by which the brain maintains correct alignment of the eyes to prevent diplopia and strabismus, and 3) the role of ocular proprioception in localizing objects in space for accurate eye-hand coordination.

The O’Rourke Lab uses an integrated approach to study the biophysics and physiology of cardiac cells in normal and diseased states. Research in our lab has incorporated mitochondrial energetics, Ca2+ dynamics, and electrophysiology to provide tools for studying how defective function of one component of the cell can lead to catastrophic effects on whole cell and whole organ function. By understanding the links between Ca2+, electrical excitability and energy production, we hope to understand the cellular basis of cardiac arrhythmias, ischemia-reperfusion injury, and sudden death. We use state-of-the-art techniques, including single-channel and whole-cell patch clamp, microfluorimetry, conventional and two-photon fluorescence imaging, and molecular biology to study the structure and function of single proteins to the intact muscle. Experimental results are compared with simulations of computational models in order to understand the findings in the context of the system as a whole. Ongoing studies in our lab are focused on identifying the specific molecular targets modified by oxidative or ischemic stress and how they affect mitochondrial and whole heart function. The motivation for all of the work is to understand • how the molecular details of the heart cell work together to maintain function and • how the synchronization of the parts can go wrong Rational strategies can then be devised to correct dysfunction during the progression of disease through a comprehensive understanding of basic mechanisms. Brian O’Rourke, PhD, is a professor in the Division of Cardiology and Vice Chair of Basic and Translational Research, Department of Medicine, at the Johns Hopkins University.

Research in the Sensorimotor Adaptation--Vestibular and Oculomotor group focuses on sensorimotor adaptation to space flight and fractal statistics in physiology. Our projects aim to understand sensory processing for motor control with an emphasis on adaptive capabilities and mathematical modeling.

The Yu Lab does basic and translational research on Sensory physiology and disorders of the gastrointestinal tract.

The Ronald Schnaar Lab is involved in the rapidly expanding field of glycobiology, which studies cell surface glycans, lectins, and their roles in cell physiology. Current projects in our lab study include (1) Glycans and glycan-binding proteins in inflammatory lung diseases, (2) Ganglioside function in the brain, and (3) HIV-Tat and HIV-associated neurocognitive disorders.

Research in the John Aucott Lab focuses on the development of accurate diagnostic tests for all stages of Lyme disease. We work closely with Dr. Mark Soloski on the Study of Lyme disease Immunology and Clinical Events (SLICE), a longitudinal, matched-control study of patients diagnosed with early untreated Lyme disease. The objective is to use the collected biological samples to help identify novel Lyme disease biomarkers that can inform diagnoses, outcomes and the knowledge about disease pathophysiology.

Research in the J. Hunter Young Lab focuses on the genetic epidemiology and physiology of cardiovascular disease and its risk factors, especially hypertension, diabetes and obesity. Current activities include an observational study of hypertension among African Americans; a genetic epidemiology study of worldwide cardiovascular disease susceptibility patterns; and several population-based observational studies of cardiovascular and renal disease. A recent focus group study found that changes in housing and city policies might lead to improved environmental health conditions for public housing residents.

In the computational neuroscience Laboratory, we construct quantitative models of biological nervous systems that are firmly based on their neurophysiology, neuroanatomy and behavior, and that are developed in close interaction with experimentalists. Our main interest is neuronal function at the system level, reflecting the interaction of subsystems to generate useful behavior. Modeling is particularly important for understanding this and other system-level functions, since it requires the interaction of several pathways and neural functions. One of the functions we study is selective attention--that is, the capability of higher animals to scan sensory input for the most important information and to discard all other. Models of the neuronal basis of visual selective attention are constructed by simulating them on digital computers and comparing the results with data obtained from the visual and somatosensory systems of primates. We pay particular attention to the mechanisms involving the implementation of neural mechanisms that make use of the temporal structure of neuronal firing, rather than just the average firing rate.

The Cammarato Lab is located in the Division of Cardiology in the Department of Medicine at the Johns Hopkins University School of Medicine. We are interested in basic mechanisms of striated muscle biology. We employ an array of imaging techniques to study “structural physiology” of cardiac and skeletal muscle. Drosophila melanogaster, the fruit fly, expresses both forms of striated muscle and benefits greatly from powerful genetic tools. We investigate conserved myopathic (muscle disease) processes and perform hierarchical and integrative analysis of muscle function from the level of single molecules and macromolecular complexes through the level of the tissue itself. Anthony Ross Cammarato, MD, is an assistant professor of medicine in the Cardiology Department. He studies the identification and manipulation of age- and mutation-dependent modifiers of cardiac function, hierarchical modeling and imaging of contractile machinery, integrative analysis of striated muscle performance and myopathic processes.

The Pluznick Lab is interested in the role that chemosensation plays in regulating physiological processes, particularly in the kidney and the cardiovascular system. We have found that sensory receptors (olfactory receptors, taste receptors, and other G-protein coupled receptors) are expressed in the kidney and in blood vessels, and that individual receptors play functional roles in whole-animal physiology. We are currently working to identify the full complement of sensory receptors found in the kidney, and are working to understand the role that each receptor plays in whole-animal physiology by using a variety of in vitro (receptor localization, ligand screening) and in vivo (whole-animal physiology) techniques.