Krishna Jayant

Date: 05/28/2024

Time: 1:30pm-2:30pm

Location: In Person

ABSTRACT:

Traveling waves in the mammalian cortex mediate vital aspects of animal cognition, such as stimuli perception and working memory. Theoretical results suggest these waves preserve timing and are critical for plasticity and coordination across long-range neural circuits. Therefore, revealing the circuit mechanisms underlying sensory-evoked traveling waves is essential to understanding the neural basis of sensory perception and motor control. In this talk, I will describe our recent efforts using 2D nanotextured transparent ECoG-style electrodes to map circuits orchestrating wave dynamics. Specifically, by concomitantly mapping local field potential and cellular ensemble dynamics (via 2P calcium imaging), we will describe the circuit features of traveling waves under active and passive whisker touch. We will show that in awake mice, both passive and active whisker touch elicited traveling waves within and across barrels, with both an early and late component lasting hundreds of milliseconds. Strikingly, wave dynamics reflected the value of the tactile stimulus and were found to predict behavioral outcomes. We describe how the late wave component is i) strongly modulated by motor feedback, ii) complements a sparse ensemble pattern across layer 2/3 which we resolved via a balanced-state network model with distributed top-down feedback, and iii) aligns with regenerative Layer 5 apical dendritic Ca2+ spikes. Our results establish a model in which translaminar spacetime patterns, organized by motor cortical feedback, sculpt touch-evoked traveling waves. Last, and time permitting, I will briefly describe our recent work on traveling waves shaping motor control.

SPEAKER BIO:

Krishna Jayant is an assistant professor at Purdue University’s Weldon School of Biomedical Engineering. His laboratory’s research focuses on delivering biophysically based accounts of behaviorally relevant computations using novel electrical and optical neurotechnologies. Projects in the lab cover various topics, including the examination of synaptic and dendritic computations in individual neurons and networkwide circuit computations that underlie sensorimotor integration, including synucleinopathies. Dr. Jayant completed his graduate training in electrical and computer engineering at Cornell University, where he worked with Dr. Edwin Kan on CMOS-based bioelectronics. He subsequently completed postdoctoral training at Columbia University with Dr. Rafael Yuste, Dr. Ken Shepard, and Dr. Ozgur Sahin, researching cutting-edge neurotechnologies to probe synaptic and dendritic biophysics. In addition to the NIH Director’s New Innovator Award, Dr. Jayant has been recognized as an NIH NIBIB Trailblazer awardee, a Human Frontiers Science Young Investigator grant awardee, a Ralph E. Powe Junior Faculty Enhancement Award, and is also a recipient of an Air Force Office of Scientific Research DURIP award.