My laboratory is driven by two goals:
First, we seek to understand the fundamental building blocks of motor behavior.
Second, we seek to understand the plasticity of motor behavior and the elaboration of motor skill from these building blocks.
These central goals lead naturally to several different projects. These all using animal model systems, as a means to achieve an understanding of modularity and plasticity across species and following injury.Project 1:
We seek to record in spinal cord, muscles, and to analyze the structure of the musculoskeletal system and movements composition to understand the circuitry involved at the spinal level. Our core hypothesis in this project is that the spinal circuits are modular and organized into collections of motor primitives. These are building blocks best suited to the constructing movements that are of the highest evolutionary significance, and that every animal of a species must perform routinely in order to survive and reproduce. Project 1 site.Project 2:
We use neurorobotics, brain machine interfaces (BMIs), and robot rehabilitation and a range of recording techniques. We seek to record neuromotor activity during normal voluntary tasks, and novel tasks (e.g., using brain machine interfaces and reinforced changes in walking), and after spinal cord injuries when descending systems are severely challenged for compensations. We focus on trunk and hindlimb motor cortex. Our core hypothesis in this project is that cortical plasticity works cooperatively with modular spinal systems, to augment, extend or replace the spinal functions as needed for novel skills or recovery of function after injury. This work links naturally to spinal cord injury research, to neuroengineering and augmenting technologies, and to basic science questions in motor control. Project 2 site.Project 3:
This project was conceived in support of the others, because of the limitations of existing recording technologies and paucity of tools available. The new electrode technologies we are testing are based on braided electrodes of ultrafine wires that can bend and flex without overlystressing the surrounding brain or spinal cord (which are fragile and have the consistency of soft jello). Our core hypothesis is that the open lattice and high flexibility of braids will minimize tissue inflammation and stress and enable long term recordings and neural interfaces, even in otherwise very difficult brain and spinal cord sites. Project 3 site.
These three projects require collaborations of neuroscientists, of engineers, and thus of neuroengineers trained to speak the languages and collaborate across both domains. We recruit and train both neuroscientists, kinesiologists, biomechanicians, and bioengineers as graduate students in order to have a team that talks and operates freely across disciplines. Research Translational Potential
Motor Modularity after injury and rehabilitation; Neuroengineeering and new neuroprostheses designs; Neurorobotic Rehabilitation Strategies to Promote Functional Recovery after Spinal Cord or otherInjury
Simon Giszter did his B.A. in the Natural Sciences at Cambridge University, UK. He did his Ph.D. in Biology at the University of Oregon under the mentorship of Dr. Graham Hoyle, and he did postdoctoral fellowships at UCLA, in the Crump Institute for Biomedical Engineering, and at MIT, in the Department of Brain and Cognitive Sciences, under the mentorship of Institute Professor Dr. Emilio Bizzi. He was promoted to Research Scientist at MIT before then joining Drexel College of Medicine (while it was still in one of its former iterations, the Medical College of Pennsylvania and Hahnemann University). He is now a professor in the Department of Neurobiology and Anatomy at Drexel University College of Medicine, with a joint appointment in the School of Biomedical Engineering and Health Systems, at Drexel.
The Lab Team
David Logan, Ph.D, Post-doc
John Lee, B.S., MD/PhD Graduate Student in Medical Engineering.
Qi Yang, B.S., Ph.D. Graduate Student in Neuroscience.
Josie Van Loozen, Ph.D. Graduate Student in Neuroscience.
Kendall Schmidt (Ankudovich), Ph.D. Graduate Student in Biomedical Engineering.
1. Hart CB, Giszter SF. (2010) A neural basis for motor primitives in the spinal cord. J Neurosci. 2010 Jan 27;30(4):1322-36.
2. Kargo WJ, Giszter SF. (2008) Individual premotor drive pulses, not time-varying synergies, are the units of adjustment for limb trajectories constructed in spinal cord. J Neurosci. 2008 Mar 5;28(10):2409-25.
3.Hart CB and Giszter SF (2004) Modular premotor drives and unit bursts as primitives for frog motor behaviors. J Neurosci. 2004 Jun 2;24(22):5269-82.
4. Kargo WJ and Giszter. SF. (2000). Rapid correction of aimed movements by summation of force field primitives. J. Neurosci. 20(1):409-426.
Function in spinal rats that walk
5. Giszter SF, Hockensmith G, Ramakrishnan A, Udoekwere UI.(2010) How spinalized rats can walk: biomechanics, cortex, and hindlimb muscle scaling--implications for rehabilitation. Ann N Y Acad Sci. 1198:279-93.
6. Giszter SF, Davies MR, Ramakrishnan A, Udoekwere UI, Kargo WJ. (2008) Trunk sensorimotor cortex is essential for hindlimb weight-supported locomotion in adult rats spinalized as P1/P2 neonates. J. Neurophysiology. 100(2):839-51. Epub 2008 May 28.
7. Giszter SF Davies MR and Graziani V (2008) Coordination strategies for limb forces during weight-bearing locomotion in normal rats, and in rats spinalized as neonates. Exp. Brain Research 190(1):53-69. Epub 2008 Jul 9.
8. Giszter SF Davies MR Graziani VG (2007) Motor strategies used by rats spinalized at birth to maintain stance in response to imposed perturbations. J. Neurophysiol. 97(4):2663-75
BMI control of trunk and locomotion and cortex motor plasticity
9. Song W, Giszter SF. (2011) Adaptation to a cortex-controlled robot attached at the pelvis and engaged during locomotion in rats. J Neurosci. 2011 Feb 23;31(8):3110-28.
10. Song WG and Giszter SF (2009) Multiple Types of Movement Related Information Encoded in Hindlimb/Trunk Cortex in Rats and Potentially Available for Brain Machine Interface Controls. IEEE Trans Biomed Eng. 56(11 Pt 2):2712-6. Epub 2009 Jul 14.
11. Oza CS, Giszter SF. 2014. Plasticity and alterations of trunk motor cortex following spinal cord injury and non-stepping robot and treadmill training. Exp Neurol. 2014 Apr 3;256C:57-69. doi:10.1016/j.expneurol.2014.03.012.
12. Hsieh FH and Giszter SF (2011) Robot-driven Spinal Epidural Stimulation Compared withConventional Stimulation in Adult Spinalized Rats. IEEE-EMBS Conference Proceedings. Boston, MA.
13. Kim TG, Branner A, Gulati T, and Giszter SF (2013) Braided multi-electrode probes: mechanical compliance characteristics and recordings from spinal cords. J Neural Engineering. Aug;10(4):045001. doi: 10.1088/1741-2560/10/4/045001. Epub 2013 May 31
14. US Patent US8639311B2: Sensing probe comprising multiple, spatially separate, sensing sites. Jan 28, 2014.
15.US Patent US8534176B2: Method and Apparatus for braiding microstrands. Sept 17, 2013