Judith A. Hirsch
Associate Professor of Biological Sciences
Research Overview
Somehow, the cerebral cortex translates the dappled images it receives from the retina via the thalamus into a coherent perception of the visual world. Our research explores the earliest stages of visual cortical processing. Specifically, we ask how thalamocortical connections and circuits within the striate cortex itself resolve basic features of the visual scene. The main approach is whole-cell recording with dye-filled electrodes from the thalamus and the cortex in vivo. With this technique we can resolve synaptic integration during vision and ultimately correlate physiological response with anatomical profile.Individual projects are designed to explore key aspects of cortical integration, such as interaction between synaptic input and intrinsic properties of the membrane, functional specializations of intracortical pathways and the synaptic basis and physiology of responses to visual pattern. In recent work, we mapped the spatial structure of thalamic and cortical receptive fields to help understand the basis of sensitivity to stimulus orientation and asked how synaptic processing changes with position in the cortical microcircuit to learn about the origin of selectivity for features such as motion. Current work explores contributions of different types of inhibitory cell to specific properties like orientation tuning and to global mechanisms like the regulation of the excitability. In addition, in collaboration with colleagues at the University, we have begun to develop our biological studies in concert with computational models of visual function.
Contact Information
- Web Site:
- Home Page
- E-mail:
- jhirsch@usc.edu
- Mailing Address:
- University of Southern California
3641 Watt Way HNB 328
Los Angeles, CA 90089-2520 - Office Location:
- HNB 328
- Office Phone:
- (213) 821-2210
- Lab Location:
- HNB 328
- Lab Phone:
- (213) 821-2406
- Fax:
- (213) 740-5687
Education
- Ph.D., Neurophysiology, University of Wisconsin, Madison, 1986
Research Images
Selected Publications
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Wang X, Wei Y, Vaingankar V, Wang Q, Koepsell K, Sommer FT, Hirsch JA. (2007) Feedforward excitation and inhibition evoke dual modes of firing in the cat's visual thalamus during naturalistic viewing. Neuron. 55(3):465-478. -PubMed
Stepanyants A, Hirsch JA, Martinez LM, Kisvárday ZF, Ferecskó AS, Chklovskii DB.(2008) Local potential connectivity in cat primary visual cortex. Cereb Cortex. 18(1):13-28. -PubMed
Hirsch JA, Martinez LM. (2006) Laminar processing in the visual cortical column. Curr Opin Neurobiol. 2006 Aug;16(4):377-384. -PubMed
Hirsch JA, Martinez LM. (2006) Circuits that build visual cortical receptive fields.Trends Neurosci. 29(1):30-39. -PubMed
Martinez LM, Wang Q, Reid RC, Pillai C, Alonso JM, Sommer FT, Hirsch JA. (2005) Receptive field structure varies with layer in the primary visual cortex. Nat Neurosci. 8(3):372-379. -PubMed
Hirsch JA, Martinez LM, Pillai C, Alonso JM, Wang Q, Sommer FT. (2003) Functionally distinct inhibitory neurons at the first stage of visual cortical processing. Nat Neurosci. 6(12):1300-1338. -PubMed
Hirsch JA. (2003) Synaptic physiology and receptive field structure in the early visual pathway of the cat. Cereb Cortex. 13(1):63-9. Review. Erratum in: Cereb Cortex. 13(4):434. -PubMed
Hirsch JA, Martinez LM, Alonso JM, Desai K, Pillai C, Pierre C. (2002) Synaptic physiology of the flow of information in the cat's visual cortex in vivo. J Physiol. 540(Pt 1):335-350. -PubMed
Martinez LM, Alonso JM, Reid RC, Hirsch JA. (2002) Laminar processing of stimulus orientation in cat visual cortex. J Physiol. 540(Pt 1):321-333. -PubMed
Hirsch JA, Alonso JM, Reid RC, Martinez LM. (1998) Synaptic integration in striate cortical simple cells. J Neurosci. 18(22):9517-9528. -PubMed