The mammalian brain is a complex network with a hierarchical organization, in which electrical activities of neurons underlie neural computation and behavioral control. In this seminar Dr. Lu will discuss his previous works on the anatomical dissection of neuronal circuits and on the functional representation of memory engram, as well as his ongoing work on the neural coding of motor skill learning. Using semi-automatic pipeline for large-scale microscopic imaging and image processing, Dr. Lu reconstructed the first mammalian connectome, i.e., the complete wiring diagram of a neural circuit. It revealed surprisingly high degree of configuration diversity in neural circuits performing the same function, challenging the century-old idea of optimal neural wiring. In order to decode the activity patterns of neuronal assemblies underlying the memory engram, Dr. Lu co- developed a microendoscopic approach to image the functional assembly of neurons representing the mouse’s experiences in different environments. The study reveals that distinct environments evoke characteristic patterns of neuronal activation, which progressively stabilize upon repeated exposures. Dr. Lu’s ongoing work takes advantage of high-speed two-photon fluorescent microscopy to capture the activity patterns of neuronal ensembles in awake mice learning a fine motor skill. He will also discuss his future directions combining optical and electrical probing and manipulation of functional states of neural circuits.
Dr. Ju Lu received his Bachelor of Engineering degree from Tsinghua University in China in 2002, majoring in microelectronics. He received Ph.D. in neuroscience from Harvard University in 2008. He is currently an Assistant Project Scientist at University of California, Santa Cruz. His research interest focuses on developing and applying optical, electrophysiological, and analytic tools to decode the connectivity and the activity patterns of neural circuits at multiple organizational levels, and to manipulate the functional states of specific assemblies of neurons.