Srivatsun (Vatsun) Sadagopan, PhD
Training faculty, Center for Neuroscience/Univ. of Pittsburgh (CNUP)
Member, Center for the Neural Basis of Cognition (CNBC)
Biomedical Science Tower 3
3501 Fifth Avenue Room 10021
Pittsburgh, PA 15261
vatsun at pitt dot edu
2015 - Assistant Professor, Department of Otolaryngology
University of Pittsburgh, Pittsburgh, PA.
2013 - 2014 Postdoctoral associate, Laboratory of Neural Systems
The Rockefeller University, New York, NY.
2011 - 2013 Leon Levy Postdoctoral Fellow, Advisor: Winrich Freiwald
Laboratory of Neural Systems
Shelby White and Leon Levy Center for Mind, Brain and Behavior
The Rockefeller University, New York, NY.
2008 - 2011 Postdoctoral fellow, Advisor: David Ferster
Department of Neurobiology and Physiology
Northwestern University, Evanston, IL.
2001 - 2008 PhD in Neuroscience, Advisor: Xiaoqin Wang
The Solomon H. Snyder Department of Neuroscience,
Johns Hopkins University School of Medicine, Baltimore, MD.
1997 - 2001 Bachelor of Technology (Hons.) Biochemical Engineering and Biotechnology
Indian Institute of Technology, Kharagpur, India.
We hear sounds such as speech in a wide range of listening conditions, of which few parameters are under our control. For example, sounds might emanate from different locations, at different intensities, in the presence of other noise or distracting sounds, and in echoing settings. For a given sound, each of these environmental variables alters the physical pressure waveform that impinges on our eardrums; yet, we are able to interpret these varied physical waveforms as arising from the same underlying sound. In other words, our perception of sounds is perceptually invariant to a large number of nuisance parameters, and one of the primary functions of the ascending auditory system is to develop this perceptual invariance. The research thrust of our laboratory is to study the mechanisms by which such invariance properties are generated in the neural responses of primary and higher auditory cortex. In particular, we focus on one behaviorally important set of sounds - vocal communication sounds.
Understanding how the brain processes sounds in realistic conditions is a central problem in auditory neuroscience. The best example of the impressive human ability to 'tune in' on particular sounds in noisy environments is the “cocktail party effect” – where a listener in a crowded, loquacious room can attend to one particular voice of interest. This ability is unmatched by modern speech recognition algorithms, which have accurate performance in silence, but greatly degraded performance in such real-world situations. Yet, the mechanisms and computations by which the brain accomplishes this feat is largely unknown. We hope to answer the fundamental questions of what computations the brain might be using to solve this problem, and what underlying circuitry supports these computations.
We use a range of techniques to answer these questions, including in-vivo array and multi-electrode extracellular recordings and in-vivo whole-cell intracellular recordings from awake (and eventually behaving) animals. We expect to add in-vivo two-photon imaging, inducible genetics and viral tract-tracing to this suite of techniques in the near future.
Realistic listening conditions pose a significant challenge to patients with communication disorders such as dyslexia, some sensory aphasias, to the hearing impaired, and to the elderly with age-related decline in hearing. We hope to provide fundamental insights into these disorders by understanding the circuit mechanisms by which the brain extracts meaningful signals from noise.
Sadagopan S, Temiz-Karayol NZ & Voss HU (2015). High-field functional magnetic resonance imaging of vocalization processing in marmosets. Scientific Reports (5): 10950. BioRxiv doi: http://dx.doi.org/10.1101/010561.
Sadagopan S & Ferster D (2012). Feedforward origins of response variability underlying contrast invariant orientation tuning in cat visual cortex. Neuron 74: 911 – 23.
Bartlett EL*, Sadagopan S* & Wang X (2011). Fine frequency tuning in monkey auditory cortex and thalamus. The Journal of Neurophysiology 106: 849 – 59. (*equal contribution)
Sadagopan S & Wang X (2010). Contribution of inhibition to stimulus selectivity in the primary auditory cortex of awake primates. The Journal of Neuroscience 30: 7314 – 25.
Sadagopan S & Wang X (2009). Nonlinear receptive fields underlie feature selectivity in primary auditory cortex. The Journal of Neuroscience 29: 11192 – 202.
Sadagopan S & Wang X (2008). Level invariant representation of sounds by populations of neurons in primary auditory cortex. The Journal of Neuroscience 28: 3415 – 26.
Pilar Montes Lourido PhD, 2016 -
Shi Tong Liu, Bioengineering PhD candidate, 2015 -
Vikram Mukherjee, 2017
Vighnesh Viswanathan, Applied Math & Neuroscience Junior, Spring 2016
Patrick Haggerty, Bioengineering Sophomore, Summer 2015 (SSOE fellowship)
We are grateful to the Pennsylvania Lions Hearing Research Foundation and The Samuel and Emma Winters Foundation for their support of our research.