Simon Giszter, Ph.D.

Dept. of Neurobiology and Anatomy
2900 Queen Lane, Philadelphia, PA 19129
Phone: 215 991 8412


Research Interests

Description: Description: Description: Description: C:\Users\Admin\Desktop\GiszterWeb\frank.jpgMy laboratory encompasses two research approaches.

The first approach involves basic research into the spinal cord's capabilities for organization and control of limb biomechanics. For these studies we utilize the spinal frog and more recently the decerebrate rat. The spinal frog is a robust preparation that exhibits complex reflex behaviors. These behaviors capture many of the fundamental biomechanical and control problems faced by tetrapods. Recent results obtained from microstimulation of frog spinal cords suggest that there may exist a few primitives or modules for controlling force and movement during reflex behaviors and perhaps motor control generally.

In these experiments we recorded the biomechanical limb responses as force-fields generated in the limb by the spinal cord. We discovered that there were few force-field types and that these types were stable and scaled in magnitude with increasing stimulation strength or duration. These force-field types could be combined by simple vector superposition to allow construction of novel force-fields for limb control. Early work also suggested that these primitives were located in specific regions in the spinal cord. Recent dense microstimulation maps confirm that only a few force directions are represented. Specific patterns of muscle activity can be used as predictors of the force directions. Finally, the data demonstrate that the spatial distributions of force directions elicited by microstimulation can be related to the spinal cord structure and in particular the interneuron target fields of different descending and sensory systems in the grey matter. Exploration of how these systems and their control interact in the generation and control of reflex and locomotory behaviors is the current focus of this project. We have successfully demonstrated reflex behaviors are constructed and adjusted using combinations of force-field primitives. We also use small haptic robot designed for virtual reality systems to present different virtual environments to the frog limb. We have shown considerable effects of environmental compliance on limb response.

Besides its basic interest, ultimately this project may contribute to functional electrical stimulation, teleoperation, and design of biomorphic robots and contribute to understanding and promoting rehabilitation and plasticity for recovery of function.

Recovery of function following injury involves growth, reconnection of cells and adjustment of synaptic strength. These changes cooperate to produce recovery of system level behaviors. At the system level, function in the repaired CNS involves adjustments of the computational tasks carried out by the nervous system. These compensate for or utilize the alterations, deficits and mistakes in the new information flows. From this perspective understanding of the biomechanics and control engineering of the normal, injured and recovered systems is essential to assess the successes and failures of clinical interventions. The second approach used in my laboratory involves the examination of locomotion and stance kinematics, force production, and spinal and cortex organization and controls in normal, transected and transplanted rats. This works in collaboration with the laboratories of Drs. Fischer, Murray, Moxon, Simansky, Lemay and Tessler. By developing a comprehensive set of experimental tests of motor control organization and its differences we hope to shed light both on normal motor control, systems level organization, and on what systems coordinate recovery. The notion of motor primitives is used as an organizing idea in both projects.

Selected publications 

Bizzi, E., Mussa-Ivaldi, F.A. and Giszter,S. (1991) Computations underlying the execution of movement, a biologicalperspective. Science, 253: 287-291.

Mussa-Ivaldi, F.A. and Giszter,S.F. (1992) Vector Field Approximation: A computational paradigm for motorcontr ol and learning. Biological Cybernetics, 67, 491-500.
Giszter, S.F., Mussa-Ivaldi, F.A.and Bizzi, E. (1993) Convergent force fields organized in the frog spinalcord. J. Neuroscience, 13:467-491.

Giszter, S.F., Kargo W, ShibayamaM and Davies M.R. (1998) Fetal transplants placed into neonatal spinaltransections in rats rescue axial muscle representations in adult motorcortex and improve recovery of l ocomotion. J Neurophysiol 80:3021-3030.

Kargo WJ and Giszter SF, (2000),Rapid corrections of aimed movements by combination of force-field primitives.J Neurosci 20:409-426 

Kargo, WJ and Giszter SF, (2000)Afferent roles in hindlimb wiping reflex: free limb kinematics and motorpatterns. J Neurophysiology 83(3):1480-1501     

Giszter SF and Kargo WJ (2000) Conservedtemporal dynamics and vector superposition of primitives in frog wipingreflexes during spontaneous extensor deletions. Neurocomputing 32-33:775-783 

Giszter SF Moxon KA Rybak I ChapinJK (2000) A neurobiological perspective on design of humanoid robots andtheir components IEEE Intelligent Systems 15(4): 64-69 

Giszter SF Grill W Lemay M MushahwarV and Prochazka A (2000) Intraspinal microstimu lation: techniques, perspectivesand prospects for FES, pp101-138 in Neural prostheses for restoration ofSensory and motor function ed. KA Moxon and JK Chapin CRC Press 

Giszter, S.F., Loeb E., Mussa-Iva ldiF.A. and Bizzi E. (2000) Dense mapping of frog lumbar spinal cord: organizationof force and muscle use. Human Movement Science 19 :597-626

Giszter1 Simon F., and Kargo WilliamJ,(2001) Modeling of dynamic controls in the frog wiping reflex: force-fieldlevel controls. Neurocomputing. 38-40:1239-1247 

Giszter SF (2001) Quantization ofmotor drive into time-frequency atoms using independent component analys isand matching pursuit algorithms 2001 Proceedings IEEE/EMBS Istanbul Turkey.

In press

Giszter SF Moxon KA Rybak I ChapinJK (2001) Neurobiological and neur orobotic approaches to design of a controllerfor a humanoid motor system   Robotics and Autonomous Systems.

Giszter SF (2001/2) Motor primitives.In Handbook of Brain Theory and Neural Networks (2nd ed) MIT Press 

Giszter SF (2001) Biomechanicalprimitives and heterarchical control in tetrapod locomotion. In Neurotechnologyfor biomimetic robots ed Ayers J Rudolph A and Davis J MIT Press 


Research Faculty

Almut Branner, PhD

Corey Hart, PhD

Graduate Students:

Arun Ramakrishnan (Visit personal website)

TaeGyo Kim

Chintan Oza

Kiki Yang

John Lee

Research Technician

Kavon Noorbehesht

Past students and staff

Tanuj Gulati, PhD

Ubong Ime Udoekwere, PhD

WeiguoSong, PhD

FuHan Hsieh, PhD

Martin M. Przeworski

Lollise Mbi

Yu-Li Liang

Vidyaangi Patil

Bronwyn Kilby

Jonathan Scabich

Sergey Markam, PhD

Cindy Agnew



Rat Projects:

Rat Trunk Adaptation to Lifting Elastic Fields

Simon Giszter, Ubong Ime Udoekwere , Arun Ramakrishnan

Peripheral Nerve-Bridge- novel neuro-rehabilitative approach to SCI in rats

Simon Giszter, Jack Martin, Ubong Ime Udoekwere, Osamu Uemera, Rebecca Jay

Locomotor Recovery after SCI using Epidural Stimulation

FuHan Hsieh, Simon Giszter

BMI and Neural understanding of locomotory adaptations

WeiGuo Song, Simon Giszter

Frog Projects:

Sensorimotor integration for motor primitives-an anatomically correct approach

Simon Giszter, Arun Ramakrishnan, Jonathan Nissanov, Louise Bertrand, Kiisa Nishikawa, Jenna Monroy, Theodore A. Uyeno , Dinesh Pai, Shinjiro Sueda

Frog Spinal Cord: Segmental organization and response to multiple stimulation

TaeGyo Kim , Simon Giszter

Frog spinal cord and reflex organization as a set of motor primitives

Corey Hart, Simon Giszter, Sergey Markin

Other Projects:

Braided tetrodes: A novel electrode technique

TaeGyo Kim, Arun Ramakrishnan, Ubong Ime Udoekwere, Simon Giszter

Past Projects

Rat motor primitives in spinalcord injury and functional recovery

Jonathon Scabich, Simon Giszter, Cindy Agnew

MotorCortex organization following SCI and recovery:

Cindy Agnew, Jonathon Scabich, Simon Giszter, Bronwyn Kilby, Karen Moxon

Biomechanics of functional recovery after SCI

Bronwyn Kilby, Cindy Agnew, Simon Giszter, Jed Shumsky

Novel methods of deep brain stimulation and FNS

Graham Ellis-Davies, Martin M. Przeworski, Michel Lemay, Ken Simansky , Karen Moxon, Jonathon Scabich, Simon Giszter

Laboratory Funding

PI, laboratory and staff currently supported by

NIH R01 NS 40412 : Force-Field controling frog spinal and voluntary motor behavior 2001-2006 PI Simon Giszter
NIH PPG P01 NS24707  : Project4 - Plasticity of Motor Primitives 2001-2006 Project PI Simon Giszter,Program PI Marion Murray
NIH Training grant:  Understandingthe biological basis of brain injury and disease , PI Itzhak Fischer 1998-2003
Drexel Spinal cord center grant
Drexel Major Research Initiative (MRI)
Drexel Neuroengineering Program

Past support:

NIH R29 NS34640 : Force-field Controlin spinal Reflexes of the Frog PI Simon Giszter 1995-2000
NIH NS07287 Traininggr ant:  Mechanisms promoting Rehabilitation, PI M Murray 1994-1999,1999-2004
ASRI grant  PI Simon Giszter1995-1996
Drexel Spinal cord center grant



OurNeurobiology Department homepage

OurSpinal cord group and some of my colleagues here homepage

Michel Lemay'swebpage

KarenMoxon's Webpage

KenSimansky's homepage

GrahamEllis-Davies homepage

Terry Sanger's homepage

Stefan Schaal 's homepage

ChapinLab colleagues

IlyaRybak's page and links

Emilio Bizzi's lab and links


Kiisa Nishikawa’s Lab

Dinesh K. Pai’s lab

Jonathan Nissanov’s Lab

Conferences organized by myself and colleagues:

"TheNIPS 2000 Neuroprosthetic and neurorobotic workshop homep age "

"The2000 NCM Computational Motor Systems Satellite Meeting "

"The1998 NCM Computational Motor Systems Satellite Meeting "

See also:

Our Neuroengineering program page

Neuralcontrol of movement society homepage

RecentNeurotechnology and robots conference homepage

Humanoidrobots conference

Robotsurgery ;) homepage

Neurosciencegraduate program homepage

Departmento f Neurobiology and Anatomy at Drexel homepage

Neuroengineeringgroup of joint faculty at Drexel

The Neuroprosthetics group

International Society of Biomechanics

Society for Neuroscience

The Neural Control of Movement Society

Publications (chronological)

Most recent list of publications:

Refereed papers chronologically:

Giszter, S.F., Koreisha, S.G. and Franklin, R.F. (1984) Asymmetriesof antennal control of two millipede species: an approach using VectorAutoregressive Moving Average Time Series Analysis.  J. Math. Biol.,19, 281?302.

Giszter, S.F., McIntyre, J. and Bizzi, E. (1989) Kinematic strategiesand sensorimotor transformations in the wiping movements of frogs. J. Neurophysiol., 62, 750?767.

Mussa-Ivaldi, F.A. and Giszter, S.F. (1991) A field?approximation approachto the execution of motor pla ns. Fifth Intern'tl. Conf. Advanced Robotics,Pisa, Italy.

Mussa-Ivaldi, F.A., Bizzi, E. and Giszter, S.F. (1991) Transformingplans into actions by tuning passive behavior: a field?approximation approach.Proc. 1991 IEEE Int'l. Symposium on Intellige nt Control.

Bizzi, E., Mussa-Ivaldi, F.A. and Giszter, S. (1991) Computations underlyingthe execution of movement, a biological perspective.  Science, 253:287?291.

Bizzi, E., Mussa-Ivaldi, F.A. and Giszter, S. (1992) Does the nervoussystem use equilibrium? point control to guide single and multiple joint movements?  Behavioraland Brain Sciences.

Mussa-Ivaldi, F.A. and Giszter, S.F. (1992) Vector Field Approximation:A computational paradigm for motor control and learning. Bio logical Cybernetics,67, 491-500.

Giszter, S.F., Mussa-Ivaldi, F.A. and Bizzi, E. (1993) Convergent forcefields organized in the frog spinal cord. J. Neuroscience, 13:467-491.

Loeb, E., Giszter, S.F., Borghesani, P., Bizzi, E. (1993) The roleof afference in convergent force fields elicited in the frog spinal cord.Somatosensory and Motor Behavior,  10:81-95.

Giszter, S.F. (1993) Behavior networks and force fields for simulatingspinal reflex behaviors of the frog. 2nd. International con ference on theSimulation of Adaptive Behavior, (From Animals to Animats 2), 172-181,MIT Press.

Giszter, S.F. (1994) Reinforcement tuning of action synthesis and selectionin a virtual frog. 3rd. International conference on the Simulation of Adaptive Behavior, (From Animals to Animats 3),

291-301, MIT Press.

Mussa-Ivaldi, F.A., Giszter S.F., Bizzi E. (1994) Linear combinationof primitives in vertebrate motor control. Proceedings and National Academyof Sciences . 91:7534-7538

Giszter S.F. (1 994) Combination of primitive force-generating motorelements during reflex behaviors. Proc. 16th Annual IEEE Conf on Engineeringin Biology and Medicine. Proceedings on CD-ROM and bound volume.

Bizzi E, Giszter SF, Loeb E, Mussa-Ivaldi FA and Saltiel P (1995) Modularorganization of motor behavior in the frog's spinal cord.  Trendsin Neurosciences.  Review. 18:442-446 .

Giszter SF Kargo W and Davies 1996 Motor Primitives in the spinal cordas a basis for motor learning and action Paper s of 1996 AAAI Fall SymposiumTech Rep FS-96-02 Embodied Cognition and Action. AAAI Press

Tessler A, Fischer, I Giszter S.F. Himes BT, and Murray M. (1996) EmbryonicSpinal Cord Transplants Enhance Locomotor Performance in spinalized Newborn Rat s. (In: Neuronal regeneration, reorganization and repair. Issueed. FJ Seil.) pp 291-303 Advances in Neurology Vol 72.  New York,Raven Press

Miya D, Giszter SF, Mori F, Tessler A, Murray M 1997 Fetal transplantsalter the development of function after spinal cord transection in newbornrats. J Neurosci 17(12):4856-4872

Giszter SF 1997  Modularity, extensibility, response time andstability: compromises in spinal reflex behaviors. IEEE Paper I-97138BProc IEEE American Control Conference . Volume 5: 3277-3280

Giszter, S.F., Kargo W, Shibayama M  and Davies M.R. (1998) Fetaltransplants placed into neonatal spinal transections in rats rescue axialmuscle representations in adult motor cortex and improve recovery of locomotion.J N europhysiol 80:3021-3030

Giszter SF, Graziani V, Kargo W, Hockensmith G, Davies MR, SmeraskiC and Murray M (1999)

Pattern generators and cortical maps in locomotion of spinal injuredrats. Extended abstract Proc NYAS 860: 554-555

Kargo W, Dav ies MR and Giszter SF (1999) Segmental afferent controlof hindlimb wiping in spinal frogs. Extended abstract Proc NYAS 860: 456-457

Loeb E P, Giszter SF, Saltiel P, Mussa-Ivaldi FA and Bizzi E (1999)Output units of motor behavior: an experimental an d modeling study. Journalof Cognitive Neuroscience 12:1-20.

Kim D, Adipudi V, Shibayama M, Giszter SF, Tessler A, Murray M and Simansky KJ (1999) Direct agonists for serotonin (5-HT2) receptorsenhance locomotor function in rats that received n eural transplants afterneonatal spinal transection. J Neurosci. 19(1):6213-6224

Kargo WJ and Giszter SF, (2000),  Rapid corrections of aimed movementsby combination of force-field primitives. J Neurosci 20:409-426

Kargo, WJ  and Giszte r SF, (2000) Afferent roles in hindlimb wipingreflex: free limb kinematics and motor patterns.  J Neurophysiology83(3):1480-1501

Giszter SF and Kargo WJ (2000) Conserved temporal dynamics and vectorsuperposition of primitives in frog wiping re flexes during spontaneousextensor deletions.  Neurocomputing 32-33:775-783

Giszter SF Moxon KA Rybak I Chapin JK (2000) A neurobiological perspectiveon design of humanoid robots and their components  IEEE IntelligentSystems 15(4): 64-69

Giszter, S.F.,Loeb E., Mussa-Ivaldi F.A. and Bizzi E. (2000) Densemapping of frog lumbar spinal cord: organization of force and muscle use.Human Movement Science 19 :597-626

Giszter1 Simon F., and Kargo William J,(2001) Modeling of dynamic contr olsin the frog wiping reflex: force-field level controls. Neurocomputing.38-40:1239-1247 

Giszter SF (2001) Quantization of motor drive into time-frequency atomsusing independent component analysis and matching pursuit algorithms 2001Proceedi ngs IEEE/EMBS Istanbul Turkey.

Giszter, S. F., Moxon, K. A., Rybak, I. A., and Chapin, J. K. (2000) A neurobiological perspective on humanoid robot design. IEEE Intelligent Systems 15: 64-69

Refereed Chapters:

Giszter, S.F., Bizzi, E. and Mussa-Ivaldi, F.A. (1992) Motor organizationin the frog's spinal cord.  In: F.H. Eckman and C.D. Deno (Eds.),Analysis and Modelling of Neural Systems.  Kluwer Press, Moffett Field,CA.Giszter, S.F., Bizzi, E. and Mussa-Ivaldi, F.A. (1992) Movement primitivesin the frog's spinal cord.  In: F.H. Eckman and C.D. Deno (Eds.),Neural Systems.  Kluwer Press, Moffett Field, CA.

Giszter, S.F. , Davies MR, and Kargo WJ (2000) P erspective. Augmentingpostural primitives in spinal cord: Dynamic force-field structures usedin trajectory generation.Ch 25 pp 334-346  in  Biomechanics andNeural control of Movement. ed. Winters and Crago. Springer-Verlag.

Giszter SF Gri ll W Lemay M Mushahwar V and Prochazka A (2000) Intraspinalmicrostimulation: techniques, perspectives and prospects for FES pp 101-138in Neural prostheses for restoration of Sensory and motor function ed.KA Moxon and JK Chapin CRC Press

Giszter, S. F. and Kargo WJ (2000) Movement organization in the frogspinal cord: Prerational intelligence?  pp 323-342  In Pre-rational intelligence: Adaptive Behavior and Intelligent Systems withoutSymbols and Logic- Volume 1. Ed. H. Cruse, J Dean, and H Ritter. Studiesin Cognitive Systems series.  Kluwer Academic Press

In press: 

Motor Control. In Workshop on artificial Neuroethology.  D McFarlandand O Holland. Oxford UP

Giszter SF Biomechanical primitives and he terarchical control in tetrapodlocomotion. In Neurotechnology for biomimetic robots ed Ayers J RudolphA and  Davis J MIT Press

Invited Chapters:

Giszter, S.F., Mussa-Ivaldi, F.A. and Bizzi, E. (1991) Equilibriumpoint mechanisms i n the spinal frog.  In: M. Arbib and J.P. Ewert(Eds.), Visual Structures and Integrated Functions.  Plenum, N.Y.

Mussa-Ivaldi, F.A., Giszter, S.F. and Bizzi, E. (1991) Motor?spacecoding in the central nervous system. 55th Cold Spring Harbo r Symp. onQuantitative Biology, The Brain.

Giszter, S.F., Mussa-Ivaldi, F.A. and Bizzi, E. (1992) The organizationof limb motor space  in the spinal frog. in Experimental Brain ResearchSeries. vol 22:  Control of arm movement in space.Giszter, S.F. (1994) Conceptual issues in frog wiping behaviors. In: Handbook of Brain Theory and Modelling. ed. M. Arbib

Chapter in  proceedings of Sensorimotor Integration Workshop,Sedona AZ.

In press:

Giszter SF Motor primitives Handbook of Brain Theory and Neural Networks(2nd ed) MIT Press



Website maintained by: Arun Ramakrishnan

Website last updated: 2012