Restoring neural function through neural prosthetic “bypass” Ziv Williams, MD Associate Professor in Neurosurgery Faculty, Harvard-MIT Health Sciences and Technology Faculty, Harvard Medical School Program in Neuroscience Massachusetts General Hospital Harvard Medical School Boston, MA 02114
23
Embed
Restoring neural function through neural prosthetic “bypass” Ziv Williams, MD Associate Professor in Neurosurgery Faculty, Harvard-MIT Health Sciences.
This document is posted to help you gain knowledge. Please leave a comment to let me know what you think about it! Share it to your friends and learn new things together.
Transcript
Restoring neural function through neural prosthetic “bypass”
Ziv Williams, MD
Associate Professor in Neurosurgery
Faculty, Harvard-MIT Health Sciences and Technology
Faculty, Harvard Medical School Program in Neuroscience
Massachusetts General Hospital
Harvard Medical School
Boston, MA 02114
Re-growing disrupted CNS circuits
Brain-machine-interface
• No need to restore normal physiological continuity• In principal, can be learned very rapidly (hours to
days)• Has the potential for recovering full motor function
(across multiple degrees of freedom)
Williams, et al. Nature Neurosci. 2003Williams et al. Exp Brain Res. 2005
Decoding neural activity based on native directional tuning
Vx (t) = a + =-m
n w()n(t ) (t)
Vx position along the x-axis t timet time laga y-interceptn neuronal firing ratew weight for each neuron e residual error
• Model training• Model decoding
Functional cortical-to-spinal bypass
• Benefit of restoring one’s own paralyzed limb.
• In principal, can be used to functionally connect any proximal and distal neural site.
• Cortical to spinal • Cortical to nerve• Cortical to muscle
Shanechi M, et al. Nature Neurosci. 2012Shanechi M, et al. Nature Comm. 2014
Brain - Neural recordings
Spinal cord - Neural stimulation
Restoring other motor functions
• Premotor cortex – planned target of movement
• Primary motor cortex – ongoing trajectory
• Supplementary motor area – movement sequences
1:1
( | ) ) exp( ( | )( | ) ( 1:12)ck
KcK
k
Ni c i c ik Sp N k iSS
Shanechi M, et al. Nature Neurosci. 2012
Motor control based on native neural plasticity?
• In principal, any brain area.
Williams Z, et al. Nature Neurosci. 2006Haroush K & Williams Z. Cell 2015
• Shanechi M, Hu R, Williams Z. A cortical-spinal neural prosthesis for targeted limb movement in paralyzed primate avatars. Nature Comm. 2014 Feb 18;5:3237.
• Haslinger R, Pipa G, Lewis LD, Nikolić D, Williams Z, Brown E. Encoding through patterns: regression tree-based neuronal population models. Neural Comput. 2013 Aug;25(8):1953-93.
• Shanechi MM, Hu RC, Powers M, Wornell GW, Brown EN, Williams Z. Neural population partitioning and a concurrent brain-machine interface for sequential motor function. Nature Neurosci. 2012 Dec;15(12):1715-22.
• Williams Z, Eskandar EN. Selective enhancement of associative learning by microstimulation of the anterior caudate. Nature Neurosci. 9: 562-8, 2006.