Edward Chang, MD

Professor
Neurological Surgery
415-502-7346

Speech Mechanisms

A unique and defining trait of human behavior is our ability to communicate through speech. My laboratory is interested in determining the basic mechanisms that underlie speech perception and production.  While much of this processing has been localized to the peri-sylvian cortex, including Broca’s and Wernicke’s areas, the fundamental organizational principles of these neural circuits are completely unknown.

To address this, my laboratory applies a variety of experimental approaches including psychophysics, local field potential and microelectrode array recordings, electrocortical stimulation, and real-time signal processing.  These methods allow us to examine both local circuitry and global network dynamics spanning multiple cortical and sub-cortical regions with unparalleled spatial and temporal resolution in humans.

Our central goal is to provide a mechanistic account for the major properties of speech behavior in normal speakers and those with language disorders. Our ongoing research is not only deepening understanding of speech and its disorders, but also is leading directly to safer brain mapping methods to preserve language function during awake neurosurgical procedures. 

Current Projects

Speech perception
1. How do invariant cortical sensory representations give rise to categorical perception?
2. How does response selectivity of auditory cortical neurons account for high-order, complex sound processing?
3. How does the auditory cortex maintain robust speech representation in multi-speaker or noisy environmental contexts?

Speech production
1. What is the basic functional organization of the speech motor cortex and Broca’s area?
2. How are syllable sequences encoded in these brain regions to generate meaningful word forms?
3. What are the mechanisms by which sensory feedback is used to guide vocal motor control?

Lab Members

Matt Leonard, PhD
Assistant Adjunct Professor
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Heather Dawes, PhD
Program Manager
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Fatemeh Khatami, PhD
Postdoctoral Fellow
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Gopala Anumanchipalli, PhD
Postdoctoral Fellow
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Han Gyol Yi, PhD
Program Manager
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Josh Downer, PhD
Postdoctoral Fellow
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Kristin Sellers, PhD
Postdoctoral Fellow
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Maryam Bijanzadeh, PhD
Postdoctoral Fellow
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Neal Fox, PhD
Postdoctoral Fellow
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Pengfei Sun, PhD
Postdoctoral Fellow
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William Schuerman, PhD
Postdoctoral Fellow
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Yulia Oganian, PhD
Postdoctoral Fellow
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Claire Tang
Neuroscience Graduate Student
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David Conant
Neuroscience Graduate Student
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David Moses
Bioengineering Graduate Student
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Josh Chartier
Bioengineering Graduate Student
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Deanna Wallace, PhD
Specialist
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Ruofan Cai
Junior Specialist
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David Chang
Junior Specialist
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Ben Lucas
Assistant Specialist
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Matthias Sjerps
Visiting Scholar
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Dharshan Chandramohan
Associate Specialist
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Morgan Lee
Clinical Research Coordinator
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Lab Website

Publications: