introduction to neural prosthesis
TRANSCRIPT
Neural Prosthetic Engineering
Neural Prosthesis
• A device that connects directly with the nervous system to replace or supplement sensory or motor function.
• A device that improves the quality of life of a neurologically impaired individual so much that he/she is willing to put up with the surgery, gadgetry, etc.
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Neural Prosthetic Engineering
Successful Areas of Neural Prosthesis
• (Bionic Ear)
• Hearing: Cochlear Implant
• Vision: Retinal Implant
• Parkinson’s Disease: DBS (Deep Brain Stimulation)
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Neural Prosthetic Engineering
Why these three?
• Success in Cochlear Implant
• The other two were inspired by its (the CI’s) success.
• The Cochlear and Retinal implants are sensory prosthetics, using electrical stimulation of neurons.
• The DBS deals with motion disability yet uses CI like neuronal stimulation.
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Neural Prosthetic Engineering
Why was CI so successful?
• Spatially isolated space was available for the electrode array. The electrode array was still electrically connected to the target neurons.
• Timely development of the transistor based microelectronics technologies that made the electronics small (wearable, implantable) but powerful.
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http://www.cochlearamericas.com/
Neural Prosthetic Engineering
What are needed in NP? (1)
• External unit is needed if there is a signal to process.
• Speech is the signal to process in Cochlear Implant
• Image is the signal to process in Retinal Implant
• There is no external signal to process in DBS.
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External Unit
Neural Prosthetic Engineering
Speech Processor, An example of External Unit
www. bionicear.com, www.medel.com, www.cochlear.com7
Neural Prosthetic Engineering
What are needed in NP? (2)
• Internal Unit (Implantable Unit)
• This unit generates electrical signals, and apply them to the array of electrodes that stimulate target neurons.
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External Unit Internal Unit
Neural Prosthetic Engineering
What are needed in NP? (3)
• Communication (Connection) between the two.
• If the connection is wired, it is called “percutaneous connection”,
• Percutaneous connection is simplest, best with signal to noise ratio, but there is risk for infection.
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External Unit Internal Unit
Neural Prosthetic Engineering
What are needed in NP? (4)• Thus modern NP uses wireless communication
(telemetry).
• The telemetry requires extra circuit to transmit and receive signals from the external unit to the internal one.
• There are forward telemetry and reverse telemetry.
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External Unit Internal Unit
Neural Prosthetic Engineering
System example: Cochlear Implant
Wearable
Speech
Processor
Microphone
External
Coil
Internal
Coil
Implantable Current
Stimulator
Inserted
Electrode array
① Sound Signal
② RF Modulation
③ Data & Power
Transmission
⑤ Stimulation
Pulse train
④ Signal
Demodulation
⑥ Auditory Cortex
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Neural Prosthetic Engineering
Problems addressed
• Cell loss is the common problem.
• Cells that act as transducers (sensors) for hearing and vision– Hair cells in cochlea in hearing impairment
– Photoreceptor cells in retina for vision impairment
• Cells that are essential in controlled movement:– Substantia Nigra cells in Parkinson’s disease
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Neural Prosthetic Engineering
Possible solutions
• Stem cells: IPSC (Induced Pluripotent Stem Cells) are the typical approach
• However, these are not proven safe for clinical applications yet.
• Currently Neural Prosthesis is the only working solution: An array of electrodes are inserted to electrically stimulate surviving neighbor neuron cells to substitute or replace the lost functions.
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Neural prosthetic Milestones
1930 1940 1950 1960 1970
1934: Electronic hearing aid developed
1945: Invention of transistor
1956 Nobel Prize of Physics awarded to Shockley, Bardeen and Brattain
1952: Hodgkin-Huxley theory of action potential
1957: 1st cochlear implant developed
1958: Internal pacemaker developed
1959: MOSFET invented (BL,D.Khang)
1961: 1st motor prosthesis for foot drop in hemiplegics
1961: Silicon chips first appear(TI, J. Kilby)
1963: CMOS invented (Fairchild, Wanlass)
1977: Bone-anchored hearing aid made available in Europe
1977: VLSI developed(Modular design by Mead and Conway)
1973-74: organized clinical trials of the 1st wearable cochlear implant begin
1971: Microprocessor invented (Intel, 4004)
1979: 1st
auditory brainstem implant
Engineering/Computer MilestonesFinn, Warren E., and Peter G. LoPresti, eds. Handbook of neuroprosthetic methods. CRC Press, 2002.
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Neural prosthetic Milestones
1980 1985 1990 1995 2000
1980: 1st successful 1-channel cochlear implant in a child
1981: IBM PC,STM invented
1986-95: FES allows paraplegics to stand
1981: Peripheral nerve bridge implanted into spinal cord of rat
1980: silicon microelectrode for extracellular recording begun
1995: - Human trials of visual cortex prosthesis - German group begin Subretinal implant
2000: - FDA authorizes Optobionics to begin human trials of Artificial Silicon Retina (ASR)
- FDA approval of 1st
middle-ear implant- FAD approval of auditory brainstem implant
1996: Optic nerve prosthesis development begins in Belgium
Engineering/Computer Milestones
1985: MS Windows developed
1988: MIT-Harvard, Johns Hopkins begin research on epiretinal implant
1989: Intel 486 processor
1997: FDA approval of DBS on thalamus for Parkinson’s Disease
2000: Deep Brain Stimulation (ACTIVA) develped to treat Parkinson’s disease
1998: Google
Finn, Warren E., and Peter G. LoPresti, eds. Handbook of neuroprosthetic methods. CRC Press, 2002.16
Neural prosthetic Milestones
2000 2005 2010 2015
2008: iPhone 3G
Engineering/Computer Milestones
2010: iPhone 4
2012: iPhone 5
2014: iPhone 6
2013: FDA approval of Secondsight Argus II epiretinal prosthesis
2002-2004: 16-channel retinal prosthesis Argus I developed
2007: clinical trials of 60-channel Argus II begin
2005-2009: 1500 channel subretinal photodiode array by German group
2003: completion of the Human Genome Project
2005: Optogenetic system for mammalian neuron
2001: 1st dual-core processor (IBM)
2006: 1st Tesla all-electric vehicle
2004: Human-implanted BCI
2004: Facebook launched
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Our envinronment
• We are certainly a Biomedical Engineer
• Biomedical engineer is who challenges many problem in the
modern heath care system.
• Biomedical engineer is who challenges many problem in the
modern heath care system.
• To be more specific, we could be called a Neural Engineer.
• Some people might say we study Artificial Organs (Devices
for replacement or augmentation of bodily functions)
• We can join professor societies such as IEEE EMBS
(Engineering in Medicine and Biology Society). They hold
annual meeting called EMBC (Engineering in Medicine and
Biology Conference).
• BMES (Biomedical Engineering Society) is another major
biomedical engineering society.
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IEEE EMBS
• IEEE Engineering in Medicine and Biology society• The IEEE is the largest international professional organization in the world
and accommodates 37 different societies and councils under its umbrella structure.
• The EMBS represents the foremost international organization serving the
need of more than 8000 biomedical engineering members around the world.
• publications:
• Transaction on Biomedical Engineering(TBME: a monthly journal)
• Transactions on Biomedical Circuits and Systems
• Transaction on Rehabilitation Engineering
• Transaction of Information Technology in Biomedicine(two quarterly journals))
• IEEE Engineering in Medicine and Biology magazine(a bimonthly magazine)
19http://www.ieee.org/embs
Conferences and Meetings we can travel to
• Institute of Electrical and Electronic Engineers(IEEE) Engineering in Medicine and
Biology Society(EMBS) Conference
• IEEE EMBS Neural Engineering Conference
• Biomedical Engineering Society(BMES) Meeting
• Neural Interfaces Conference
• Biomedical Circuits and Systems(BioCAS) Conference
• Conference on Implantable Auditory Prostheses(CIAP)
• European Symposium on Paediatric Cochlear Implantation(ESPCI)
• Asia Pacific Symposium on Cochlear Implant and Related Sciences(APSCI)
• American Cochlear Implant Alliance CI Symposium
• The Eye and The Chip Meeting
• Annual Meetings of Association for Research in Vision and Ophthalmology (ARVO)
• International Neuromodulation Society(INS) World Congress
• Society for Neuroscience(SFN) Conference
• World Society for Stereotactic Functional Neurosurgery(WSSFN)
• International Federation for Medical & Biological Engineering(IFMBE)
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Journals we can publish our research in
• Includes, but not limited to,
• Journal of Neural Engineering
• Journal of Neuroscience Methods
• Medical & Biological Engineering &
Computing
• Biomedical Instrumentation and
Technology
• Journal of Clinical Engineering
• Computer Methods and Programs
in Biomedicine
• Neural Computation
• Science
• Nature
• Small
• Optics Express
• Otology and Neurotology
• Journal of Neuromodulation
• Sensors and Materials
• Sensors & Actuators
• Computational and Mathematical
Methods in Medicine
• ACS Nano 21
• Biosensors and Bioelectronics
• Investigative Ophthalmology &
Visual Science
• Clinical & Experimental
Otorhinolaryngol
• Optics Letters
• Biotechnology and Bioengineering
• Neuromodulation
• Nanotechnolgy
• Optics Communications
• NeuroImage
• Invest Ophthalmol Vision Science
• Tissue Engineering
• Bioelectromagnetics
• Sensors
• Journal of Materials Science:
Materials in Medicine
• Journal of Biomedicine and
Biotechnology
• Biochimica et Biophysica Acta
• Medical Engineering & Physics
• And more.
Related Youtube videos
• Hearing CI
• https://www.youtube.com/watch?v=00WOao4kpwM
• CI simulations
• https://www.youtube.com/watch?v=iwbwhfCWs2Q
• A day of a CI user
• https://www.youtube.com/watch?v=pk_7MVqpnIk
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