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3/18/2015
1
New Approaches to Functional Restoration in the 21st Century
Randolph J. Nudo, PhDProfessor and Vice Chair of Research
Dept Rehabilitation MedicineDirector, Landon Center on Aging
Marion Merrell Dow Distinguished Professor in AgingUniversity of Kansas Medical Center
Kansas City, KS
Physical Medicine and Rehabilitation Grand Rounds19 March 2015
Landon Center on Aging
Theories of recovery after brain injury
Reversal of diaschisis Behavioral compensation Adaptive plasticitySynaptogenesisLTP, LTDAxonal sproutingVicarious functioning in spared areas
Stroke: Acute Intervention
IV tPA
Mechanical Embolus Removal in Cerebral
Ischemia (MERCI)4.5 hour window
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Promising treatments from basic research
• calcium channel antagonists• NMDA receptor antagonists • CDP-choline• free radical scavengers• GABA agonists• Sodium channel antagonists• glycine site of NMDA receptor
Improvement in clinical outcome: 0No improvement: 115+
Neuroprotective agents reaching phase III efficacy trials:
Therapeutic windows after stroke
Acute phase Chronic phase
Pharmacotherapy Physiotherapy
neurotrophins, stem cells, modulators (D-amphetamine), genomic approaches, electrophysiologicmodulation,etc.
Post‐Injury Experience Promotes Plasticity in Peri‐Infarct Motor Cortex
Nudo et al., Science, 1996; CI Therapy photo courtesy E. Taub
Animation courtesy NHK, Japan
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Remodeling Of Motor Cortex (M1): Use and Disuse
Nudo et al., J Neurosci, 16:785, 1996; Milliken et al., 109(5):1268-82, 2013
Effects of Brain Injury on Functional and Structural Organization of Cerebral Cortex
Frost et al., J Neurophysiol, 2003; Dancause et al., J Neurophysiol, 2006; Dancause et al., 2005
Potent effect of behavioral experience
Behavior
Neuronal structure/functionCNS injury
Stimulation modalities
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Mature neuroprosthetic applications
Deep Brain Stimulation Cochlear Implant
Invasive brain‐machine interface approaches
Neural signals recorded from the brain as input commands to control external environment
CyberkineticsBrainGate
Hochberg et al., 2012, Nature, 485:372.
TDCS
Open‐loop neuromodulationafter stroke: non‐invasive approaches
rTMS
Stimulation + behavioral experience
epidural stimulation
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Induction of plasticity in motor topography by intracortical microstimulation
Nudo, et al., 1990
Forelimb area
Vibrissa area
+ +
-
Jacobs & Donoghue, 1991
Closed‐loop neuromodulation
Combines neural recording, signal processing and microstimulation in a single device for closed‐loop operation
NeuroPace RNS system
EEG-driven stimulation
NeuroPace Pivotal Trial: Responsive Stimulation
Heck et al., Epilepsia 2014
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Adaptive DBS: the next wave of treatment?
Ann Neurol, 74(3):449‐57, 2013
Un
ifie
d P
ark
inso
n's
Dis
ea
seR
atin
g S
cale
N = 8
LFP-driven stimulation
Adaptive DBS
Little et al., Ann Neurol, 2013
• Power savings (44%)• Beta bursts less frequent
Rationale for closed‐loop neuroprosthetic systems to restore function after
brain injury
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Neurophysiology of Prehension
Modified from Gardner E P et al. J Neurophysiol 2007;97:1656‐1670
Functional Importance of S1‐M1 Connectivity
M1 HAND AREAanterior posterior
Friel et al., J Neurophysiol, 94:1312, 2005.
Examining remote plasticity in rats after motor cortex injury
Nudo, Ch 28 In: Evolution of Nervous Systems, 2007.
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Activity‐Dependent Plasticity: Theoretical Basis
“When one cell repeatedly assists in firing another, the axon of the first cell develops synaptic knobs … in contact with the soma of the second cell.”
‐‐ Donald Hebb, 1949 The Organization of Behavior
“Cells that fire together wire together.”‐‐Modern maxim (Carla Shatz)
Collaboration with Pedram Mohseni, PhD, Dept. Electrical Engineering and Computer Science, Case Western Reserve
University
Development of ASIC for spike‐driven stimulation in rats
P. Mohseni & colleagues, IEEE J. Solid‐State Circuits (JSSC), April 2011
Miniaturized System Assembly
Azin et al., IEEE Trans Biomed Engin. 2011Pedram Mohseni, PhD
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Next steps
• Mechanisms (physiology, anatomy)• Non‐human primate model
Proof‐of‐concept study in rat traumatic brain injury model
1. Create TBI in motor cortex (CFA) using CCI model.2. Implant microdevice; record spikes in RFA, stimulate S1 forelimb area.3. Spike‐driven (activity‐dependent) ICMS 24 hrs/day (7.5 ms; 28 ms).4. No behavioral training; periodic behavioral testing.5. Compare to “no stimulation”, “open‐loop stimulation”.
Guggenmos et al., PNAS, 2013
David Guggenmos, PhD
Effects of Injury on Motor Performance 8 Days Post‐injury
Guggenmos et al., PNAS, 2013
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Effects of Injury on Motor Performance 8 Days Post‐injury
Guggenmos et al., PNAS, 2013
Evidence for enhanced functional connectivity after ADS
S1 RFA
?
Van Acker, et al., under review
Rapid facilitation in anesthetized rats
S1 RFA
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Geschwind's Disconnection Syndromes
Catani M , ffytche D H Brain 2005;128:2224-2239
© The Author (2005). Published by Oxford University Press on behalf of the Guarantors of Brain. All rights reserved. For Permissions, please email: [email protected]
The study of corticocorticaldisconnections has a long tradition in behavioral neurology.
Neuroprosthetics for spinal cord repair
Shawn Frost, PhD
Characterizing spike activity after spinal cord injury
Frost et al., J Neurosurg Spine, 2013; Frost et al., under review
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Neuronal firing in S1 after spinal cord injury
Frost et al., under review
Daly & Wolpaw, Lancet Neurology, 2008
Challenges to Translation
Rehabilitation Medicine Research at KUMC
• Create a top 10 integrated, translational Rehabilitation Research program at KUMC
• Partner with Patient Centered Outcomes Research Institute at KUMC, with an emphasis on functional restoration and post‐acute care period
• Build Primary areas of excellence in (1) the Neurosciences and (2) Outcomes research
Mission: To advance excellence in rehabilitation care through exceptional basic and applied research
Strategic Plan
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Rehabilitation MedicneResearch at KUMC: Focus Areas
Rehabilitation
Research
Neuroscience; Stem Cells
Outcomes Research
Musculo‐skeletal;
Sports; Gait; Osteoarthritis
Oncology Pain and
Rehabilitation
Rehabilitation Engineering; Robotics; Orthotics;
Telemedicine
Cortical Plasticity Laboratory 2015
Scott Barbay, PhDJordan Borrell, BSDavid Bundy, PhD (July 2015)Caleb Dunham, BSShawn Frost, PhDDavid Guggenmos, PhDHeather Hudson, PhDMax Murphy, BSAndrea Pack, BSKelly Rodriguez, BSEdward Urban III, MD, PhDHongyu Zhang, MD, PhDNeurosurgery residentsSummer students
Pedram Mohseni, PhD Case Western Reserve U
Michela Chiappalone, PhD Alberto Alverna
Istituto Italiano di TecnologiaBrian Andrews, MD
KUMC Plastic SurgeryStacey Dejong, PT, PhD
University of IowaDavid McNeal, PhD
Oregon Health Science CenterGustaf Van Acker, MD, PhD
Case Western Reserve U
NIHDept. DefenseRonald D. Deffenbaugh Foundation