Physiology Brownbag Seminars – Fall 2022

Physiology “brown-bag” lunchtime seminars are normally held on selected WEDNESDAYS at noon in Applied Physiology Building, room 1253 (or as indicated). Special seminar dates/times outside of the regular schedule are indicated as such.

Contact Dr. Boris Prilutsky, boris.prilutsky@biosci.gatech.edu, to be considered as a future speaker, added to the e-mail distribution list, if you would like to meet with a speaker, or for other seminar-related inquiries.
For directions: Applied Physiology

SEMINAR: Wednesday, August 17, 2022

It’s not just the work you do, it’s how you do it: adventures in muscle and tendon mechanics and energetics

Glen Lichtwark, PhD
School of Human Movement and Nutrition Sciences
The University of Queensland

Abstract

Glen will provide a background of his research and how it has evolved over time and led full circle to re-evaluation of factors that influence energy consumption during movement, for the purposes of better prediction of how much energy it costs to move.

Bio: Glen Lichtwark is a Professor in the School of Human Movement and Nutrition Sciences, The University of Queensland, and a current Australian Research Council Future Fellow (2020–2024). He was awarded his Ph.D. in 2005 from University College London (UK) and has worked as a postdoctoral fellow at the Royal Veterinary College (UK), Imperial College (UK), Griffith University (2007-2009), before joining The University of Queensland in 2010. He has subsequently established a research program in biomechanics and skeletal muscle structure and function, particularly focused on how muscle and tendon structure influences the economy of movement and ability to control or power movement. This research is applied across different contexts: developing a basic understanding to how muscles have evolved for purpose, for example: determining mechanisms of muscle contracture in cerebral palsy; examining how muscle micro- and macrostructure adapts to different forms of training. His research has received funding from the Australian Research Council, National Health and Medical Research Foundation, Cerebral Palsy Alliance, and a range of industry partners including the Australian Institute of Sport and the Asics Oceania. Dr. Lichtwark has been a council member for the International Society of Biomechanics, and is currently the Australia New Zealand Society of Biomechanics representative on the Journal of Biomechanics editorial board and current Associate Editor for the Journal of Physiology.

Host: Greg Sawicki, PhD
Time: 12:00 – 1:00 PM
Location: 555 14th street NW, Atlanta 30318; Applied Physiology Building, room 1253; Zoom link.

SEMINAR: Wednesday, October 26, 2022

Computational modeling of brainstem-spinal locomotor circuits

Jessica Ausborn, PhD
Department of  Neurobiology and Anatomy
Drexel University College of Medicine

Abstract

Locomotion is essential for animal survival and needs to be continuously adapted for different tasks such as the generation of different locomotor speeds, gaits, and turning movements. Neuronal circuits in the spinal cord contain all the necessary components to generate the locomotor rhythm and pattern, controlling intra- and interlimb coordination. Descending circuits from the brainstem then drive and select different aspects of locomotion. The organization of these neural circuits is beginning to be elucidated as the advent of targeted genetic approaches enables our experimental collaborators to dissect the brainstem locomotor command circuitry into functionally distinct neuronal populations. Using these tools, key neuronal populations involved in the control of locomotor gait have been identified. A series of recent studies have also identified relevant populations and their up and downstream targets in the mesencephalic locomotor region and the reticulospinal system that control the speed and direction of locomotion. However, the inherent complexity of the brainstem-spinal circuitry is difficult to capture with experimental methods alone. We, therefore, use computational modeling to complement experimental studies and investigate underlying mechanisms of brainstem-spinal locomotor control at the level of genetically defined neuronal populations and their interactions. We have developed a model of brainstem-spinal circuits that integrates experimental data from different labs and provides important insight into the organization and operation of spinal locomotor circuits and the supraspinal control of locomotion.

Bio: Dr. Jessica Ausborn is an Assistant Professor at the Neurobiology & Anatomy Department at Drexel University College of Medicine. She received her Ph.D. in Neuroscience at Ulm University in Germany under the supervision of Dr. Harald Wolf. In her thesis work, she used a combination of biophysical computer models and electrophysiological experiments in the locust flight system to investigate general mechanisms of sensorimotor integration. For her postdoctoral training, Dr. Ausborn worked with Dr. Abdel El Manira at the Karolinska Institute in Sweden. In Dr. El Manira’s lab she used adult zebrafish as a model system to investigate the role of genetically identified neuron populations and their connections in the generation of locomotor frequency changes, neuron recruitment, and behavioral selection. Dr. Ausborn joined Drexel as junior faculty in an Instructor position in Dr. Ilya Rybak’s group where she used biophysical models of neural networks to investigate brainstem and spinal circuits of locomotion and respiration. Since joining Drexel, she has successfully started her own research group and accepted a tenure-track Assistant Professor position in 2020. Dr. Ausborn now uses her interdisciplinary training to seamlessly integrate the advantages of mechanistic biophysical models with experimental studies of her collaborators. Her work aims to discover mechanisms involved in sensorimotor integration, neural processing, rhythm generation, and the selection and generation of diverse and flexible behaviors.

Host: Boris I. Prilutsky, PhD
Time: 12:00 – 1:00 PM
Location: 555 14th street NW, Atlanta 30318; Applied Physiology Building, room 1253; Zoom link

SEMINAR: Wednesday, December 21, 2022

Neuromechanical models and legged robots for the investigation of adaptive locomotion mechanism in humans and animals

Shinya Aoi, PhD
Department of Mechanical Science and Bioengineering
Osaka University, Japan

Abstract

Humans and animals produce adaptive locomotion in diverse environments by skillfully manipulating their complicated and redundant musculo-skeletal systems. The locomotion is generated through dynamical interactions between the neural system, musculo-skeletal system, and environment. The analysis of measured data during locomotion has limitations to fully understand the mechanism for adaptive locomotion. We develop a motor control model for locomotion based on neurophysiological hypotheses and integrate it with a biomechanical model. We investigate the mechanism for adaptive locomotion through the computer simulation and dynamic analysis using the neuromechanical model. Furthermore, we create a legged robot and controller based on our findings and reproduce the adaptive functions during locomotion. We study various animals, including humans, such as monkey, cat, rat, and mouse, and various locomotion tasks, such as walking, running, gait transition, obstacle avoidance, and split-belt treadmill walking.

Bio: Shinya Aoi is a Professor in the Department of Mechanical Science and Bioengineering, Graduate School of Engineering Science at Osaka University in Japan. He received the BE, ME, and PhD degrees in engineering from the Department of Aeronautics and Astronautics, Kyoto University, Japan, in 2001, 2003, and 2006, respectively. He worked at Kyoto University from 2006 to 2022 and joined Osaka University in 2022 as a Professor. His study aims are to elucidate the mechanism for adaptive locomotion in humans and animals through the analysis of measured data and computer simulation of neuro-musculo-skeletal systems based on the dynamical systems theory and computational neuroscience. Furthermore, he also aims to develop the control scheme of legged robots based on the findings to achieve adaptive locomotor functions.

Host: Boris I. Prilutsky, PhD
Time: 12:00 – 1:00 PM
Location: 555 14th street NW, Atlanta 30318; Applied Physiology Building, room 1253; Zoom link