ELOS 2021

Sukhdev Roy

Sukhdev Roy, Speaker at Sukhdev Roy: Speaker for Optics Conference
Dayalbagh Educational Institute, India
Title : Low-power optogenetic control of high-frequency neural codes with single-spike resolution


One of the greatest scientific challenge is to understand the working of the brain, the most complex system in the universe. Optogenetics has revolutionized neuroscience research by enabling control of genetically modified neurons in culture, tissue and living animals with light. Natural light-sensitive proteins called ‘opsins’, are expressed transgenically in neurons to cause light-induced excitation or inhibition of neural activity. This provides opportunity to study the function of different neurons in the brain with unprecedented spatiotemporal resolution.

Intense efforts are on to discover and engineer opsins to provide better control, larger photocurrent, improved kinetics, high-sensitivity, spectral tuning, and protein stability, along with light-delivery systems and opsin-expression strategies. Experimentally testing each combination of opsin and target cell type of interest is practically impossible, and thus needs a theoretical framework. Computational optogenetics has provided tremendous opportunity to understand complex experiments, under different photo-stimulation protocols, and explore applications. It requires simulation of the photocurrent in opsins and optically-induced spiking in opsin-expressing neurons.

The talk would focus on our research on the formulation of accurate theoretical models for ultrafast optogenetic excitation using recently discovered ultrasensitive Chronos, red-shifted vf-Chrimson and ChRmine, optogenetic inhibition using newly discovered light-driven pumps namely eNpHR3.0 and Jaws, and bidirectional control with various experimentally studied and prospective opsin pairs for the first time. The study is useful in designing new optogenetic neural spiking experiments with desired spatiotemporal resolution, to provide insights into temporal spike coding, plasticity, and for curing neurodegenerative diseases, especially retinal prostheses.


Professor Sukhdev Roy received the B.Sc. (Hons.) Physics from Delhi University in 1986, M.Sc. Physics from DEI, in 1988, and PhD. from IIT Delhi in 1993. He is at present a Professor in the Department of Physics and Computer Science and has been a Visiting Professor at many universities that include, Harvard University. He has won a number of awards and fellowships and published 175 research papers. He is an Associate Editor of IEEE Access, Senior Member IEEE and SPIE, and Fellow of Indian National Academy of Engineering, National Academy of Sciences, India, IETE (India), and Optical Society of India.