Stephen V. David, Ph.D.

  • Associate Professor of Otolaryngology - Head and Neck Surgery, School of Medicine
  • Neuroscience Graduate Program, School of Medicine
  • Behavioral Neuroscience, School of Medicine

Biography

Background

Stephen David joined the OHSU faculty in February 2012. Before coming to OHSU, he received his Ph.D. in Bioengineering from the University of California, Berkeley in 2006 and subsequently completed postdoctoral work in the Institute for Systems Research at the University of Maryland, College Park.

Summary of current research

Humans and other animals are exquisitely adept at creating a coherent sense of the world from complex and continuously changing sensory inputs. Throughout development, the brain's auditory system learns to categorize and discriminate important sounds, while ignoring irrelevant but often substantial noise. State of the art audio processing systems attempt to mimic these abilities, but even common sources of environmental noise severely confound automatic speech processors and distort the output of hearing aids and prosthetics. The David lab seeks to understand the neurophysiological and computational processes that underlie the remarkable abilities of the auditory brain, with an aim of understanding communication disorders and improving engineered systems for sensory signal processing. 

Behavior-driven changes in the representation of sensory information 

During normal behavior, important information can arrive from multiple sensory modalities, and the relevance of any given stimulus can change with behavioral demands. Thus the ability to robustly identify sensory events represents a combined effort of bottom-up multimodal representations and top-down control signals that extract sensory information appropriate to the task at hand. To understand these complementary processes, the lab conducts experiments that manipulate auditory attention and study how the cerebral cortex represents sounds under different behavior conditions. Data from these studies is used to develop computational models that integrate top-down and bottom-up processing under realistic, natural conditions. 

Neural representation of natural auditory and visual stimuli 

The David Lab is also interested in basic questions of how sensory information is represented by cortical neurons, especially under the rich and varied conditions encountered in the natural environment. Work from our lab has shown that the auditory cortex represents speech and other natural stimuli using algorithms that cannot be discerned from responses to the synthetic noise and tone stimuli typically used to characterize the auditory system. Ongoing studies aim to clarify how important natural signals are represented in cortex and to characterize the circuit mechanisms that produce these representations.  

Major Milestones and Significant Discoveries

Determined that the representation of speech in auditory cortex cannot be predicted by responses to noise and tone stimuli traditionally used to characterize auditory representations Found that the reward structure of a task controls the sign of attention-driven plasticity in primary auditory cortex.

Education and training

  • Degrees

    • A.B., 1998, Harvard University
    • Ph.D., 2004, University of California

Memberships and associations:

  • Society for Neuroscience
  • Association for Research in Otolaryngology

Areas of interest

  • Representation of speech and other natural sounds in auditory cortex
  • Learning and attention-driven changes in auditory representation
  • Biological mechanisms underlying neural computations

Publications

Selected publications

  • N. Ding, J.Z. Simon, S.A. Shamma, S.V. David. (2016) Encoding of natural sounds by variance of the cortical local field potential. J Neurophys, 115(5):2389-98. PMC4922460
  • I.L. Thorson, J. Lienard, S.V. David. (2015) The essential complexity of auditory receptive fields. PLoS Comput Biol . 11(12):e1004628.
  • S.J. Slee,. S.V. David. (2015) Rapid task-related plasticity of spectrotemporal receptive fields in the auditory midbrain. J Neurosci 35(38):13090-13102.
  • M.J. McGinley, S.V. David, D.A. McCormick. (2015) Cortical membrane potential signature of optimal states for sensory signal detection. Neuron. 87(1):179-92.
  • J.M. Stafford, B.R. Jarrett, O. Miranda-Dominguez, B.D. Mills, N. Cain, S. Mihalas, G.P. Lahvis, K.M. Lattal, S.H. Mitchell, S.V. David, J.D. Fryer, J.T. Nigg, D.A. Fair. (2014) Large-scale topology and the default mode network in the mouse connectome. Proc Natl Acad Sci U S A. 111(52):18745-50.
  • N. Mesgarani, S.V. David, J.B. Fritz, S.A. Shamma. (2014) Mechanisms of noise robust representation of speech in primary auditory cortex. Proc Natl Acad Sci U S A. 111(18):6792-7

Publications

  • A sparse code for natural sound context in auditory cortex

    Current Research in Neurobiology
    1. Mateo López Espejo
    2. Stephen V. David

  • Task-specific invariant representation in auditory cortex

    eLife
    1. Charles R. Heller
    2. Gregory R. Hamersky
    3. Stephen V. David

  • A convolutional neural network provides a generalizable model of natural sound coding by neural populations in auditory cortex

    PLoS computational biology
    1. Jacob R. Pennington
    2. Stephen V. David

  • Effect of Reverberation on Neural Responses to Natural Speech in Rabbit Auditory Midbrain

    eNeuro
    1. Oded Barzelay
    2. Stephen David
    3. Bertrand Delgutte

  • A dataset of mentorship in bioscience with semantic and demographic estimations

    Scientific Data
    1. Qing Ke
    2. Lizhen Liang
    3. Ying Ding
    4. Stephen V. David
    5. Daniel E. Acuna

  • Impact of gender on the formation and outcome of formal mentoring relationships in the life sciences

    PLoS Biology
    1. Leah P. Schwartz
    2. Jean F. Liénard
    3. Stephen V. David

  • Targeted dimensionality reduction enables reliable estimation of neural population coding accuracy from trial-limited data

    PloS one
    1. Charles R. Heller
    2. Stephen V. David

  • Dissociation of task engagement and arousal effects in auditory cortex and midbrain

    eLife
    1. Daniela Saderi
    2. Zachary P. Schwartz
    3. Charles R. Heller
    4. Jacob R. Pennington
    5. Stephen V. David

  • Neuronal selectivity to complex vocalization features emerges in the superficial layers of primary auditory cortex

    PLoS Biology
    1. Pilar Montes-Louridoa
    2. Manaswini Kar
    3. Stephen V. David
    4. Srivatsun Sadagopan

  • Short-term effects of vagus nerve stimulation on learning and evoked activity in auditory cortex

    eNeuro
    1. Jesyin Lai
    2. Stephen V. David

  • Task engagement improves neural discriminability in the auditory midbrain of the marmoset monkey

    Journal of Neuroscience
    1. Luke A. Shaheen
    2. Sean J. Slee
    3. Stephen V. David

  • Complementary effects of adaptation and gain control on sound encoding in primary auditory cortex

    eNeuro
    1. Jacob R. Pennington
    2. Stephen V. David

  • Optimizing Auditory Brainstem Response Acquisition Using Interleaved Frequencies

    JARO - Journal of the Association for Research in Otolaryngology
    1. Brad N. Buran
    2. Sean Elkins
    3. J. Beth Kempton
    4. Edward V. Porsov
    5. John V. Brigande
    6. Stephen V. David

  • Pupil-associated states modulate excitability but not stimulus selectivity in primary auditory cortex

    Journal of neurophysiology
    1. Zachary P. Schwartz
    2. Brad N. Buran
    3. Stephen V. David

  • Streaming of repeated noise in primary and secondary fields of auditory cortex

    Journal of Neuroscience
    1. Daniela Saderi
    2. Brad N. Buran
    3. Stephen V. David

  • Spectral tuning of adaptation supports coding of sensory context in auditory cortex

    PLoS computational biology
    1. Mateo Lopez Espejo
    2. Zachary P. Schwartz
    3. Stephen V. David

  • State-dependent encoding of sound and behavioral meaning in a tertiary region of the ferret auditory cortex

    Nature Neuroscience
    1. Diego Elgueda
    2. Daniel Duque
    3. Susanne Radtke-Schuller
    4. Pingbo Yin
    5. Stephen V. David
    6. Shihab A. Shamma
    7. Jonathan B. Fritz

  • Focal suppression of distractor sounds by selective attention in auditory cortex

    Cerebral Cortex
    1. Zachary P. Schwartz
    2. Stephen V. David

  • Go/No-Go task engagement enhances population representation of target stimuli in primary auditory cortex

    Nature communications
    1. Sophie Bagur
    2. Martin Averseng
    3. DIego Elgueda
    4. Stephen David
    5. Jonathan Fritz
    6. Pingbo Yin
    7. Shihab Shamma
    8. Yves Boubenec
    9. Srdjan Ostojic

  • Implicit memory for complex sounds in higher auditory cortex of the ferret

    Journal of Neuroscience
    1. Kai Lu
    2. Wanyi Liu
    3. Peng Zan
    4. Stephen V. David
    5. Jonathan B. Fritz
    6. Shihab A. Shamma

  • Intellectual synthesis in mentorship determines success in academic careers

    Nature communications
    1. Jean F. Liénard
    2. Titipat Achakulvisut
    3. Daniel E. Acuna
    4. Stephen V. David

  • Encoding of natural sounds by variance of the cortical local field potential

    Journal of neurophysiology
    1. Nai Ding
    2. Jonathan Z. Simon
    3. Shihab A. Shamma
    4. Stephen V. David

  • Cortical Membrane Potential Signature of Optimal States for Sensory Signal Detection

    Neuron
    1. Matthew J. McGinley
    2. Stephen V. David
    3. David A. McCormick

  • Rapid task-related plasticity of spectrotemporal receptive fields in the auditory midbrain

    Journal of Neuroscience
    1. Sean J. Slee
    2. Stephen V. David

  • Rapid task-related plasticity of spectrotemporal receptive fields in the auditory midbrain

    Journal of Neuroscience
    1. Sean J. Slee
    2. Stephen V. David

  • Rapid Task-Related Plasticity of Spectrotemporal Receptive Fields in the Auditory Midbrain

    The Journal of neuroscience : the official journal of the Society for Neuroscience
    1. Sean J. Slee
    2. Stephen V. David

  • The Essential Complexity of Auditory Receptive Fields

    PLoS computational biology
    1. Ivar L. Thorson
    2. Jean Liénard
    3. Stephen V. David

  • Emergent selectivity for task-relevant stimuli in higher-order auditory cortex

    Neuron
    1. Serin Atiani
    2. Stephen V. David
    3. Diego Elgueda
    4. Michael Locastro
    5. Susanne Radtke-Schuller
    6. Shihab A. Shamma
    7. Jonathan B. Fritz