Bio


I am currently pursuing a PhD in Neuroscience with Krishna Shenoy in the Neural Prosthetics Systems lab. I am interested the neural basis of movement and motor feedback control. Towards this end, I am engaged in collaborative research employing multielectrode array recordings, optogenetic and electrical stimulation, haptic feedback devices, and high dimensional modeling of population dynamics.

Honors & Awards


  • Graduate Research Fellowship, National Science Foundation (2009-2012)
  • Stanford Graduate Fellowship, Stanford University (2009-2014)
  • NSF IGERT Research Fellowship, Stanford Center for Mind, Brain, and Computation (2012-present)

Professional Education


  • Doctor of Philosophy, Stanford University, NEURS-PHD (2017)
  • Bachelor of Elec Engineering, Princeton University, Electrical Engineering (2009)

All Publications


  • A coaxial optrode as multifunction write-read probe for optogenetic studies in non-human primates. Journal of neuroscience methods Ozden, I., Wang, J., Lu, Y., May, T., Lee, J., Goo, W., O'Shea, D. J., Kalanithi, P., Diester, I., Diagne, M., Deisseroth, K., Shenoy, K. V., Nurmikko, A. V. 2013; 219 (1): 142-154

    Abstract

    Advances in optogenetics have led to first reports of expression of light-gated ion-channels in non-human primates (NHPs). However, a major obstacle preventing effective application of optogenetics in NHPs and translation to optogenetic therapeutics is the absence of compatible multifunction optoelectronic probes for (1) precision light delivery, (2) low-interference electrophysiology, (3) protein fluorescence detection, and (4) repeated insertion with minimal brain trauma.Here we describe a novel brain probe device, a "coaxial optrode", designed to minimize brain tissue damage while microfabricated to perform simultaneous electrophysiology, light delivery and fluorescence measurements in the NHP brain. The device consists of a tapered, gold-coated optical fiber inserted in a polyamide tube. A portion of the gold coating is exposed at the fiber tip to allow electrophysiological recordings in addition to light delivery/collection at the tip.Coaxial optrode performance was demonstrated by experiments in rodents and NHPs, and characterized by computational models. The device mapped opsin expression in the brain and achieved precisely targeted optical stimulation and electrophysiology with minimal cortical damage.Overall, combined electrical, optical and mechanical features of the coaxial optrode allowed a performance for NHP studies which was not possible with previously existing devices.Coaxial optrode is currently being used in two NHP laboratories as a major tool to study brain function by inducing light modulated neural activity and behavior. By virtue of its design, the coaxial optrode can be extended for use as a chronic implant and multisite neural stimulation/recording.

    View details for DOI 10.1016/j.jneumeth.2013.06.011

    View details for PubMedID 23867081

  • Principles for applying optogenetic tools derived from direct comparative analysis of microbial opsins. Nature methods Mattis, J., Tye, K. M., Ferenczi, E. A., Ramakrishnan, C., O'Shea, D. J., Prakash, R., Gunaydin, L. A., Hyun, M., Fenno, L. E., Gradinaru, V., Yizhar, O., Deisseroth, K. 2012; 9 (2): 159-172

    Abstract

    Diverse optogenetic tools have allowed versatile control over neural activity. Many depolarizing and hyperpolarizing tools have now been developed in multiple laboratories and tested across different preparations, presenting opportunities but also making it difficult to draw direct comparisons. This challenge has been compounded by the dependence of performance on parameters such as vector, promoter, expression time, illumination, cell type and many other variables. As a result, it has become increasingly complicated for end users to select the optimal reagents for their experimental needs. For a rapidly growing field, critical figures of merit should be formalized both to establish a framework for further development and so that end users can readily understand how these standardized parameters translate into performance. Here we systematically compared microbial opsins under matched experimental conditions to extract essential principles and identify key parameters for the conduct, design and interpretation of experiments involving optogenetic techniques.

    View details for DOI 10.1038/nmeth.1808

    View details for PubMedID 22179551

  • Principles for applying optogenetic tools derived from direct comparative analysis of microbial opsins NATURE METHODS Mattis, J., Tye, K. M., Ferenczi, E. A., Ramakrishnan, C., O'Shea, D. J., Prakash, R., Gunaydin, L. A., Hyun, M., Fenno, L. E., Gradinaru, V., Yizhar, O., Deisseroth, K. 2012; 9 (2): 159-172

    View details for DOI 10.1038/NMETH.1808

    View details for Web of Science ID 000300029600026

  • Neocortical excitation/inhibition balance in information processing and social dysfunction NATURE Yizhar, O., Fenno, L. E., Prigge, M., Schneider, F., Davidson, T. J., O'Shea, D. J., Sohal, V. S., Goshen, I., Finkelstein, J., Paz, J. T., Stehfest, K., Fudim, R., Ramakrishnan, C., Huguenard, J. R., Hegemann, P., Deisseroth, K. 2011; 477 (7363): 171-178

    Abstract

    Severe behavioural deficits in psychiatric diseases such as autism and schizophrenia have been hypothesized to arise from elevations in the cellular balance of excitation and inhibition (E/I balance) within neural microcircuitry. This hypothesis could unify diverse streams of pathophysiological and genetic evidence, but has not been susceptible to direct testing. Here we design and use several novel optogenetic tools to causally investigate the cellular E/I balance hypothesis in freely moving mammals, and explore the associated circuit physiology. Elevation, but not reduction, of cellular E/I balance within the mouse medial prefrontal cortex was found to elicit a profound impairment in cellular information processing, associated with specific behavioural impairments and increased high-frequency power in the 30-80 Hz range, which have both been observed in clinical conditions in humans. Consistent with the E/I balance hypothesis, compensatory elevation of inhibitory cell excitability partially rescued social deficits caused by E/I balance elevation. These results provide support for the elevated cellular E/I balance hypothesis of severe neuropsychiatric disease-related symptoms.

    View details for DOI 10.1038/nature10360

    View details for Web of Science ID 000294603900027

    View details for PubMedID 21796121