Meet Our Primary Investigators

Mario Svirsky, PhD, Elad Sagi, PhD | Laboratory for Translational Auditory Research

Scientists in this laboratory study and normal and impaired human auditory system, using tools that range from behavioral to computational to physiological. Major interests of the laboratory include the study of sensory aids such as cochlear implants and hearing aids, and the development of techniques to improve clinical outcomes using such aids. Related to this is our interest in basic mechanisms of speech perception and auditory psychophysics, and their evaluation using realistic, ecologically valid procedures.

Ryan Branski, PhD

As Associate Director, Dr. Branski oversees all clinical and laboratory research within the NYU Voice Center. His research interests are diverse, but primarily include optimization of therapies for patients with voice disorders and improved characterization of the biochemical events following injury to the upper aero digestive tract. He currently has funding from the National Institutes of Health to investigate novel gene therapy techniques to alter and enhance healing following vocal fold injury.

Robert Froemke, PhD

We are social animals. Like most mammals, we engage in social interactions and activities important for our health and happiness, such as communicating, making friends, selecting mates, and raising children. These complex, essential behaviors are related to the function of specific neurochemical systems in the central nervous system- including oxytocin, adrenaline, acetylcholine, and steroid hormones like testosterone and estrogen- each of which is recruited under different behavioral conditions, arousal levels, and motivational states. These molecules exert powerful effects on neural networks, modulating and modifying synaptic connections between nerve cells to change how social identities, relationships, and the external world are represented in the brain.

Experiments performed by Dr. Froemke and his staff aim to reveal how individual synapses are changed by alterations in the patterns of neural activity, neurochemical signaling, and sensory experience. By a combination of electrical recordings from single nerve cells, computational analysis, and behavioral experiments, Dr. Froemke’s research seeks to discover basic principles and quantitative rules by which neural circuits and synapses of the mammalian cerebral cortex develop during childhood and are reorganized in adults, triggered by novelty, reward, and social contact.Machold, PhDDr. Machold's research interests are centered around the development of the mammalian brain, particularly the origin and function of the projection neurons of the auditory and ascending cholinergic arousal systems. Using transgenic fate mapping techniques in mice, I have found that in the brainstem, many of these diverse populations of neurons utilize a common proneural genetic program during their specification. Currently, I am analyzing the genetic pathways downstream of this proneural program in order to understand how the distinct projection neurons classes are specified. In particular, I am interested in the origins of the brainstem cholinergic system and its functional role in regulating overall brain activity during development and in the adult animal. Cholinergic signaling has been hypothesized to be critical for many aspects of cognition and neural plasticity, and dysfunction of the cholinergic system has been implicated in a number of neurocognitive disorders including Alzheimer’s disease, Down syndrome and autism. To test the role of cholinergic signaling in vivo, I have generated mice that lack the ability to produce acetylcholine in specific brain regions, and am currently characterizing their abnormalities at the cellular and behavioral level in order to improve our understanding of this important neuromodulatory pathway.

David M. Landsberger, PhD

David M. Landsberger received his Bachelor degree in Psychology at Brandeis University in 1995. He received his Ph.D. in Experimental Psychology from Brown University in 2001 for his work in color psychophysics. His training with cochlear implants (and the Auditory system) began working as a postdoctoral researcher with Colette McKay first at the University of Melbourne in Australia and then at Aston University in Birmingham, England. In 2007, moved to Los Angeles to work with Bob Shannon at the House Ear Institute. While at the House Ear Institute, he rose through the ranks to become an independent principal investigator running his own laboratory. In 2013, he joined the Department of Otolaryngology at the New York University School of Medicine.

His primary interest is to understand how reshaping the electric fields in the cochlea can provide better spectral resolution (and therefore better speech performance in noise) in cochlear implant patients. Other topics of interest include understanding the relative contributions of spectral and temporal cues to auditory processing, the function of the cochlear apex, as well as bilateral integration with combined electric and acoustic stimulation. He has been working on using this information to develop new sound processing strategies to provide improved sound quality, speech in noise understanding, and information transfer to cochlear implant users.

Michael Long, PhD

Nearly 20% of the population suffers from a communication disorder, such as apraxia, aphasia, stuttering, or speech difficulties related to hearing loss. Despite the pervasive nature of this problem, many questions concerning the cellular and circuit mechanisms that enable learned motor behaviors such as language production remain unanswered. Our laboratory aims to uncover the cellular and circuit properties that allow for precise coordination of a well-studied, learned motor behavior – vocal production in the songbird. Songbirds represent the most useful animal model for understanding basic vocal production mechanisms and their relation to auditory perception. We employ behavioral, electrophysiological and imaging techniques in the songbird to gain insight into the mechanisms of human speech production in health and disease. Website

J. Thomas Roland, Jr., MD, FACS

Dr. Roland's research endeavors encompass three main areas: 1. Cochlear Implant electrode development and evaluation. A model for the evaluation of new CI electrode design that includes real time fluoroscopic analysis, intra-cochlear and hydraulic force measurements and histologic evaluation is used to evaluate and suggest modifications for new electrode designs. The goal is to produce a totally atraumatic electrode design that achieves precise and reliable positioning within the cochlea. Additional studies are done in collaboration with the clinical and research team associated with the NYU CI Center. Clinical trials for new electorde designs, outcomes in challenging patient populations and radiographic analysis of electrode position are underway. 2. Neurofibromatosis type 2 management. A comprehensive center for the evaluation and treatment of patients with NF2 includes a multidisciplinary team involved in surgical and medical treatment, developing drug trials and developing strategies for hearing preservation and restoration. 3. Outcomes studies for the management of acoustic neuroma and other skull base tumors. This includes the development of facial reanimation techniques and advanced surgical techniques. Surgical management outcome, hearing preservation and restoration and novel monitoring of facial nerve and hearing are some of the studies that are underway.

David Schoppik, PhD

David trained as an undergraduate in the Gallatin School of Individualized Study at NYU, did his doctoral work with Steve Lisberger at UCSF, and worked as a postdoc with Alexander Schier and Florian Engert at Harvard University. Scientific genealogy at Neurotree.

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Susan Waltzman, PhD

Susan B. Waltzman, PhD is Professor of Otolaryngology and Co-Director of the NYU Cochlear Implant Center at NYU Langone Health. Her research is focused on two main areas: outcomes with cochlear implants and isolating the variables which affect performance with cochlear implants. Current and on-going investigations include the impact of new technology, bilateral implantation and long-term electrical stimulation in addition to outcomes in very young children, adolescents and special populations. Dr. Waltzman is the author of more than 80 peer-reviewed articles, numerous book chapters and a textbook on cochlear implants.