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Neuroscience Graduate Program at UCSF
Speech Mechanisms
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.
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?
Miranda Babiak
Research Associate
SLP., Univ. Arizona
Kristopher Bouchard
Postdoctoral Fellow
Ph.D., Neuroscience, UC San Francisco
Connie Cheung
Graduate Student-Bioengineering
B.S., Computational Engineering Science, UC Berkeley
Nima Mesgarani
Postdoctoral Fellow
Ph.D., Electrical Engineering, Univ. Maryland
Angela Ren
Research Associate
B.S., Bioengineering, UC Berkeley
Chang, EF, and Rieger, J, Johnson, KD, Berger, MS, Barbaro, NM, Knight RT. Categorical speech representation in the superior temporal gyrus. Nature Neuroscience 2010 Oct 13(11): 1428-32.
Mesgarani N, Chang EF. Selective cortical representation of attended speaker in multi-talker speech perception. Nature 2012; April 18.
Pasley B, David SV, Mesgarani N, Flinker A, Shamma SA, Crone NE, Knight RT, Chang EF. Reconstructing speech from human auditory cortex. PLoS Biology 2012;10(1):e1001251.
Chang, EF, and Edwards, E, Nagarajan, SS, Fogelson, N, Dalal, SS, Canolty, RT, Kirsch, HE, Barbaro, NM, Knight RT. Cortical spatiotemporal dynamics underlying phonological target detection in humans. Journal of Cognitive Neuroscience 2010 May 13.
Chang EF, Wang DD, Perry DW, Barbaro NM, Berger MS. Homotopic organization of right hemisphere essential language sites in right and bilateral cerebral hemispheric dominance. Journal of Neurosurgery (In Press)
Chang, EF, Clark, A, Smith, JS, Polley, MY, Chang, SM, Barbaro, NM, McDermott, MW, Berger, MS. Functional mapping-guided resection of low-grade gliomas in eloquent areas of the brain: improvement of long-term survival. Journal of Neurosurgery 2010 Jul 16.
Chang, EF, Gabriel, RA, Potts, MB, Berger, MS, Lawton, MT. Supratentorial cavernous malformations in eloquent and deep locations: surgical approaches and outcomes. Journal of Neurosurgery 2010 Jul 2.
Ganguly, K, Secundo, L, Ranade, G, Orsborn, A, Chang, EF, Dimitrov, DF, Wallis, JD, Barbaro, NM, Knight, RT, Carmena, JM. Cortical representation of ipsilateral arm movements in monkey and man. Journal of Neuroscience 2009 Oct 14; 29(41):12948-56.
Chang, EF, Turner RS, Ostrem J, Davis V, Starr PA. Neuronal responses to passive movement in the globus pallidus internus in primary dystonia. Journal of Neurophysiology 2007 Dec; 98(6):3696-707.
De Villers-sidani, E, Chang, EF, Bao, S, Merzenich, MM. Critical period window for spectral tuning defined in the primary auditory cortex (A1). The Journal of Neuroscience 2007 Jan 3;27(1):180-9.
Chang, EF, Bao, S, Imaizumi, K, Schreiner, CE, Merzenich, MM. The development of spectral and temporal response selectivity in the auditory cortex. Proceedings of the National Academy of Science 2005 Nov 8;102(45):16460-5. PMC1283465
Bao, S, Chang, EF, Woods J, Merzenich, MM. Temporal plasticity in the primary auditory cortex induced by operant perceptual learning. Nature Neuroscience 2004 Sep; 7(9):974-81.
Chang, EF, Wong, RJ, Vreman, HJ, Galo, E, Sharp, FR, Igarashi, T, Stevenson, DK, Noble, LJ. Heme oxygenase-2 protects against lipid peroxidation-mediated cell loss and impaired motor recovery after traumatic brain injury. The Journal of Neuroscience 2003 May 1; 23(9):3689-3696.
Chang, EF, Merzenich, MM. Environmental noise retards auditory cortical development. Science 2003 Apr 18; 300(5618): 498-502.
Edward Chang, M.D.
Phone
415-353-3650
Physical Address
HSW 745
Mailing Address
505 Parnassus Avenue, M779
UCSF Neurosurgery
San Francisco, CA 94143-0112
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