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[0] Porada I, Bondar I, Spatz WB, Kruger J, Rabbit and monkey visual cortex: more than a year of recording with up to 64 microelectrodes.J Neurosci Methods 95:1, 13-28 (2000 Jan 31)

[0] Serruya MD, Hatsopoulos NG, Paninski L, Fellows MR, Donoghue JP, Instant neural control of a movement signal.Nature 416:6877, 141-2 (2002 Mar 14)

{1163}
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ref: Schmidt-1993.11 tags: Normann utah array histology silicon electrode array cats date: 02-23-2017 22:03 gmt revision:4 [3] [2] [1] [0] [head]

PMID-8263001[0] Biocompatibility of silicon-based electrode arrays implanted in feline cortical tissue.

  • Tried two different times:
    • one day before euthanasia
    • 6 month implant.
  • Tried three different implants:
    • Uncoated silicon,
    • polymide coating
    • polymide coating with SiO2 adhesion layer / primer.
  • The last was the worst in terms of histopathological response.
  • Chronic implants showed relatively restrained immune response,
    • Gliosis was found around all tracks, 20-40um.
  • Encapsulation was less than 9um.
  • Edema and hemorrhage was minor but present on a subset of all implants.
  • Acute (24h) hemorrhage was more severe -- ~ 60%; edema ~ 20%.
  • Chronic histology revealed considerable macrophages w/ hemosiderin (a complex including ferritin)
  • See also [1]

____References____

[0] Schmidt S, Horch K, Normann R, Biocompatibility of silicon-based electrode arrays implanted in feline cortical tissue.J Biomed Mater Res 27:11, 1393-9 (1993 Nov)
[1] Jones KE, Campbell PK, Normann RA, A glass/silicon composite intracortical electrode array.Ann Biomed Eng 20:4, 423-37 (1992)

{1328}
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ref: -0 tags: alumina utah array electrode parylene encapsulation date: 10-23-2015 21:28 gmt revision:1 [0] [head]

Utah/blackrock group has been working on improving the longevity of their parlyene encapsulation with the addition of ~50nm Al2O3.

  • PMID-24771981 '''Self-aligned tip deinsulation of atomic layer deposited Al2O3 and parylene C coated Utah electrode array based neural interfaces
    • Process:
      • Normal Utah array dicing saw / glass frit / thinning and etch fabrication for the Utah probe.
      • Sputtered Ti, Sputtered Pt. (not sure how they mask this?)
      • Sputtered iridium oxide (SIROF, sputtered in an Ar + O2 plasma) electrode tips (again, not sure about the mask..)
      • ALD Al2O3 passivation, 50nm. Cambridge Fiji system, same as nanolab. Must take a long time!
      • A-174, aka 3-Methacryloxypropyltrimethoxysilane adhesion promoter (which presumably acts by pulling hydroxy groups off the alumina substrate; Al-O bonds have higher energy than Si-O)
      • 6um parylene.
      • Laser ablation of tips with 1000 pulses from KrF 5ns 100Hz excimer laser. Works much better than poking the electrode tips through thin aluminum foil.
      • O2 plasma descum / removal of carbon residues.
      • BOE removal of Al2O3 above the SIROF
    • Of note, ALD Al2O3 has included hydroxy bonds, which means that it gradually etches in PBS. (Pure Al2O3, as passivates aluminum parts exposed to seawater, does not?)
    • PBS also etches Si3N4, and crystaline Si.
  • IEEE-6627006 (pdf) Bi-layer encapsulation of utah array based neural interfaces by atomic layer deposited Al2O3 and parylene C
    • Atomic layer deposited (ALD) alumina is an excellent moisture barrier with WVTR at the order of ~ 10e-10 g·mm/m2·day [10-13]. But alumina alone is not suitable for encapsulation since it dissolves in water [14].
    • Demonstrated stable power-up of RF encapsulated devices for up to 600 equivalent days in 37C PBS.
      • Actual testing carried out at 57C, 4x accelerated.
  • PMID-24658358 Long-term reliability of Al2O3 and Parylene C bilayer encapsulated Utah electrode array based neural interfaces for chronic implantation.
    • Demonstrated good barrier longevity with wired Utah probes, active probes with flip-chip (Au/Sn eutectic reflow) record/stimulate circuits, and ones with bonded RF stimulation chips, INIR-6. (6th version!)
    • PBS etching of Si lead to undercutting & eventual flake-off of the SIROF, leading to dramatic impedance increase. (Figure 5 and 7).
      • no Pt under the SIROF?

{1292}
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ref: -0 tags: intracortical utah array fabrication MEMS Normann date: 08-14-2014 01:35 gmt revision:5 [4] [3] [2] [1] [0] [head]

PMID-1937509 A silicon-based, three-dimensional neural interface: manufacturing processes for an intracortical electrode array.

  • Campbell PK1, Jones KE, Huber RJ, Horch KW, Normann RA. (1991)
  • One of (but not the) first papers describing their methods / idea (I think).
  • First conf paper: {1294} (1988)
  • later adopted glass frit insulator --

{1294}
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ref: -0 tags: utah array development date: 08-14-2014 01:34 gmt revision:1 [0] [head]

IEEE-94953 (pdf) Silicon based microstructures suitable for intracortical electrical stimulation (visual prosthesis application)

  • Normann, R.A. ; Dept. of Bioeng., Utah Univ., Salt Lake City, UT, USA ; Campbell, P.K. ; Li, W.P.
  • 1988
  • not quite yet there...

{1293}
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ref: -0 tags: utah array development failure mode donoghue date: 08-14-2014 01:30 gmt revision:0 [head]

PMID-24216311 Failure mode analysis of silicon-based intracortical microelectrode arrays in non-human primates

  • Barrese JC, Rao N, Paroo K, Triebwasser C, Vargas-Irwin C, Franquemont L, Donoghue JP. (2013)
  • Most failures (56%) occurred within a year of implantation, with acute mechanical failures the most common class (48%), largely because of connector issues (83%).
  • Among grossly observable biological failures (24%), a progressive meningeal reaction that separated the array from the parenchyma was most prevalent (14.5%).

{1212}
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ref: Nordhausen-1994.02 tags: Utah array electrodes optimization date: 08-14-2014 01:24 gmt revision:2 [1] [0] [head]

PMID-8180807[0] Optimizing recording capabilities of the Utah Intracortical Electrode Array.

  • Nordhausen, Rousch, Normann (1993)
  • Originally it was designed for stimulation in a visual prosthesis.
  • Thought that the large surface area would securely anchor it to the cortex
    • Turns out you need to put gore-tex on top to keep it from being expelled.
  • Varied the exposed electrode tip to determine the optimum area.
  • Oldschool computer plots ...

____References____

[0] Nordhausen CT, Rousche PJ, Normann RA, Optimizing recording capabilities of the Utah Intracortical Electrode Array.Brain Res 637:1-2, 27-36 (1994 Feb 21)

{1278}
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ref: -0 tags: carbon fiber electrode array parylene fire sharpening microthread date: 03-20-2014 19:57 gmt revision:5 [4] [3] [2] [1] [0] [head]

PMID-23860226 A carbon-fiber electrode array for long-term neural recording.

  • Guitchounts G1, Markowitz JE, Liberti WA, Gardner TJ.
  • We describe an assembly method for a 16-channel electrode array consisting of carbon fibers (<5 µm diameter) individually insulated with Parylene-C and fire-sharpened. The diameter of the array is approximately 26 µm along the full extent of the implant.
  • Fibers from http://www.goodfellowusa.com/
    • young's modulus of 380GPa vs. tungsten 400GPa.
    • Data available from Toho Tenax
  • The absence of any report of single neuron isolation in HVC with a fixed chronic electrode implant underscores the difficulty of recording small cells (8-15um soma) with an implant whose damage length scale is large relative to the target neurons. (!!)

{1203}
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ref: Cheung-2007.03 tags: flexible electrode array Michigan probe histology Vancouver current source density EPFL polyimide date: 12-21-2013 21:07 gmt revision:5 [4] [3] [2] [1] [0] [head]

PMID-17027251[0] Flexible polyimide microelectrode array for in vivo recordings and current source density analysis.

  • Polyimide -- PI-2611 precusor.
  • 50nm Ti adhesion, 200nm Pt, both sputtered.
  • Electrodes etched via RIE in Cl2.
    • Sputtered and photo-patterned SiO2 etch mask.
  • Used regular solder to connect to a Samtec.
  • 15um total thickness.
  • 25um electrode diameter.
  • They were inserted directly (no carrier nor guide) into the brain; can be re-used.
  • Tested to 8 weeks.
  • No figure comparing silicon and polyimide, though they claim minimal GFAP response to the electrodes.

____References____

[0] Cheung KC, Renaud P, Tanila H, Djupsund K, Flexible polyimide microelectrode array for in vivo recordings and current source density analysis.Biosens Bioelectron 22:8, 1783-90 (2007 Mar 15)

{823}
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ref: Kruger-2010.05 tags: microelectrode array nichrome 7 years rhesus electrophysiology MEA Kruger oblique inverted date: 01-29-2013 07:54 gmt revision:7 [6] [5] [4] [3] [2] [1] [head]

PMID-20577628[0] Seven years of recording from monkey cortex with a chronically implanted multiple electrode.

  • Seven years!! good recordings the whole time, too. As they say, this is a clinically realistic time period. Have they solved the problem?
  • Used 12.5um Ni-Cr-Al wire insulated with 3um of polymide.
    • Wires were then glued to an 8x8 connector block using conductive epoxy.
    • Glued the bundle together with a solution of plexiglas in dichloroethane.
    • Then introduced the 0.3mm bundle into a j-shaped cannula. This allowed them to approach the gray matter inverted, from below (the white matter).
    • implanted 64 ch array into ventral premotor cortex (arm representation?).
  • No apparent degradation of recording quality over that time.
  • Had some serious problems with the quality of their connector.
    • They recommend: "Rather, the contacts on the head should be made from noble metals and be flat or shallowly hollow, so that they can be easily cleaned, and no male contacts can break."
    • Really need to amplify and multiplex prior connector (imho).
  • Claim that them managed to record from two neurons on one channel for nearly 7 years (ch 54).
  • They cite us, but only to indicate that we recommend slow penetration of the brain. They agree with our results that lowering of individual electrodes is better than all at once.

____References____

[0] Kruger J, Caruana F, Volta RD, Rizzolatti G, Seven years of recording from monkey cortex with a chronically implanted multiple microelectrode.Front Neuroengineering 3 Issue 6 (2010 May 28)

{946}
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ref: Salcman-1976.01 tags: Salcman electrodes recording chronic microelectrode array MEA original parylene date: 01-28-2013 22:18 gmt revision:8 [7] [6] [5] [4] [3] [2] [head]

PMID-1256090[0] A new chronic recording intracortical microelectrode

  • maintain that tethering is the rational way to go: it "re-establishes the normal biomechanics of the intact cranial vault". (Salcman 1972, 1973) {1010}
    • have model of electrode tip motion in response to brain-skull displacements (Goldstein and Salcman 1973) {1011}
      • Electrode would have a tip displacement of about 5um in response to a 1mm displacement of the electrode's point of entry into the skull.
      • Exponential dependence on recording amplitude and distance (Rall, 1962). Gradient: 7.5uv/um; movements of more than 1-2um can radically alter the recordnig shape.
      • Probably our electrodes work because the dura & gliosis becomes firmly attached to the electrode shafts.
    • not really an array so much as a number (10-12) of single-unit electrodes.
  • Details the process of parylene-C deposition, electrode microwelding, etc. Pretty cool stuff -- what has happened to this technology?
  • Each bubble is glued with cyanocrylate to the pia. (they too question the safety of this).
  • arrays can be manually inserted via forceps.
  • 25um iridium wire electroplated in 1-2um of gold
    • then electo-etched until the desired tip geometry is achieved, 1-3um diameter
    • and vacuum coated in 3um of parylene-C.
    • Impedance 1-2M with a 1kHz sine wave at 10nA. Impedance is inversely related to the frequency of the test current, phase angle of 70-80deg.
      • Ref Robinson, 1968.
    • We must emphasize the extreme sensitivity of electrode measurements to the test conditions. Measured values of Z e are usually increased 1-3M when the electrode has been stored away for a few days. Removing the electrode from the test bath for a few minutes in air can lead to equally large increases when the electrode is tested upon remersion. [...] might be oxide.
    • Pinholes are the usual failure mechanism (KD Wise 2004), {149}; parylene is 'pinhole-free'.
  • The connecting 25um Au lead is very flexible and imposes little stress on the iridium electrode.
    • Connecting wire coated in 12um of parylene C
    • Would prefer even finer wire, 12um.
  • Perspex window over the craniotomy; had a vent in this window which they could open.
  • Opening the vent would cause the brain to pulse, moving the electrodes through the cortex and changing neural activity.
  • Size of an electrode is limited by ability to introduce it into the brain.
    • Electrode must be introduced through the pia; as the pial vessels supply the cortex (or drain the cortex).
    • For their electrodes, P crit=0.9g ; the force necessary to penetrate the pia is 0.05 - 0.2g.
  • pure iridium is stiffer than Pt-Ir by a factor of 3 or so. (521 G N/m^2 = 521 GPa, higher than tungsten, which is 400 Gpa)
    • Pure iridium is apparently the stiffest metallic element ref
  • Interesting: "Once again we are impressed by the fact that passive recording electrodes exhibit drops in impedance in the living system which they never show on in vitro testing in protein solutions at 37C.
    • Between 40 and 50 days, a slow downward trend becomes noticeable; this trend continues for the life of the animal and asymptotically approaches values below 500k. Electrodes still record.
    • See {999}
    • Surmise that pure iridium electrodes have a different metal-electrolyte interface than more conventional metals (Pl and W).
  • Mention that the ultimate purpose is for a neural prosthesis.
    • Their then use was for recordings from M1 in monkeys and V1 from cats. (Schmidt, Bak, McIntosh 1974)
  • Ref Wise et al {1012}.

____References____

[0] Salcman M, Bak MJ, A new chronic recording intracortical microelectrode.Med Biol Eng 14:1, 42-50 (1976 Jan)

{1221}
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ref: Chestek-2011.08 tags: shenoy Utah array reliability recording BMI date: 01-28-2013 20:54 gmt revision:2 [1] [0] [head]

PMID-21775782[0] Long-term stability of neural prosthetic control signals from silicon cortical arrays in rhesus macaque motor cortex (Shenoy)

  • Overall, this study suggests that action potential amplitude declines more slowly than previously supposed, and performance can be maintained over the course of multiple years when decoding from threshold-crossing events rather than isolated action potentials.
  • During most time periods, decoder performance was not well correlated with action potential amplitude (p > 0.05 for three of four arrays)
    • Perhaps we are chasing the wrong dragon?
    • Still, minimal invasiveness / more channels is useful.

____References____

[0] Chestek CA, Gilja V, Nuyujukian P, Foster JD, Fan JM, Kaufman MT, Churchland MM, Rivera-Alvidrez Z, Cunningham JP, Ryu SI, Shenoy KV, Long-term stability of neural prosthetic control signals from silicon cortical arrays in rhesus macaque motor cortex.J Neural Eng 8:4, 045005 (2011 Aug)

{1028}
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ref: Szarowski-2003.09 tags: Michigan array silicon histology MEA cornell date: 01-28-2013 20:47 gmt revision:6 [5] [4] [3] [2] [1] [0] [head]

PMID-12914963[0] Brain responses to micro-machined silicon devices.

  • Used 2 different implants (rough & sharp corners, smooth), 2 different ways of inserting (slow, by hand).
    • Neither made much diff.
  • Measured GFAP = glial fibrillary acidic protein, a standard measure for assesing reactive gliosis [44,18,28,33,35].
    • Normally larger astrocytes were seen around larger blood vessels.
    • "At four weeks, a clear sheath of GFAP-positive astrocytes was observed"
    • GFAP labeled sheath seems to have plateaued at 6 weeks. (The sheath may be useful for our devices... )
  • Measured Vimentin, which is increased in reactive astrocytes and is not normally expressed in mature astrocytes [6,12,15,40].
    • In control animals vimentin only present in ependymal lining of the ventricles.
    • At 6 weeks, sites around both types of devices had a compact sheath of vimentin-positive astrocytes 50-100um.
    • Seemed to be a plateau as with GFAP .. though it seems to label a slightly distinct set of cells.
  • Also labeled reactive microglia with ED1 [4,19,27,36].
  • Quote: These data indicate that device insertion promotes two responses-an early response that is proportional to device size and a sustained response that is independent of device size, geometry, and surface roughness. The early response may be associated with the amount of damage generated during insertion. The sustained response is more likely due to tissue-device interactions.

____References____

[0] Szarowski DH, Andersen MD, Retterer S, Spence AJ, Isaacson M, Craighead HG, Turner JN, Shain W, Brain responses to micro-machined silicon devices.Brain Res 983:1-2, 23-35 (2003 Sep 5)

{1216}
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ref: Lee-2005.12 tags: micromotion silicon michigan array simulation strain date: 01-28-2013 03:13 gmt revision:1 [0] [head]

PMID-16317231[0] Biomechanical analysis of silicon microelectrode-induced strain in the brain.

  • Simulation.
  • Our analysis demonstrates that when physical coupling between the electrode and the brain increases, the micromotion-induced strain of tissue around the electrode decreases as does the relative slip between the electrode and the brain.
  • Argue that micromotion and shear cause lost recording sensitivity due to inflammation and astroglial scarring around the electrode.
    • This seems to be the scientific consensus ATM.

____References____

[0] Lee H, Bellamkonda RV, Sun W, Levenston ME, Biomechanical analysis of silicon microelectrode-induced strain in the brain.J Neural Eng 2:4, 81-9 (2005 Dec)

{898}
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ref: Ward-2009.07 tags: microelectrode arrays immune response recording MEA Purdue date: 01-28-2013 01:52 gmt revision:8 [7] [6] [5] [4] [3] [2] [head]

PMID-19486899[0] Toward a comparison of microelectrodes for acute and chronic recordings.

  • Good research, paper well written.
  • Results suggest significant variability within and between microelectrode types with no clearly superior array (from the abstract).
  • As Miguel mantains, "Much of the new technology, however, does not supersede traditional microwire technology in its ability to evade a host immune response".
  • Initial implantation wound initiates a cascade of immune responses which culminates in a sheath of microglia, astrocytes, various ectracellular matrix constituents, and macrophages.
    • Decent citation list -- many people have been working on MEAs.
  • Fibrous encapusulation of the electrode is much less conductive than healthy nervous tissue, hence impedance measurements can be used to track tissue response.
  • Used Osort to sort the recorded neurons.
  • "Despite differing implant locations, and thus potentially differing levels of background neural activity, and differing scarring responses, which relates to the level of thermal noise in the observed signal (Ludwig et al., 2006), no significant SNR differences were observed among the MEA types for the duration of the study."
  • SNR trends did not seem to relate to site impedance trends over the 31-day period, and by inference, the extent of tissue encapsulation and neuronal density loss.
    • SNR is likely controlled by background neural noise, not thermal noise (which would be linked to impedance).
  • Electrodes with lower impedance generally recorded units from more sites than arrays with higher impedance.

____References____

[0] Ward MP, Rajdev P, Ellison C, Irazoqui PP, Toward a comparison of microelectrodes for acute and chronic recordings.Brain Res 1282no Issue 183-200 (2009 Jul 28)

{1199}
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ref: -0 tags: histology atryocytes immune response electrode arrays lund multiple exacerbate date: 01-24-2013 19:56 gmt revision:1 [0] [head]

PMID-23091629 Multiple implants do not aggravate the tissue reaction in rat brain.

  • After six weeks, the astrocytic scar surrounding the middle out of five implants was significantly smaller compared to the single contralateral implant, suggesting that an intrahemispheric interaction might be taking place, reducing the astrocytic response around the central implant.
  • Weak (?) staining for ED1 in this study?
  • -- after 6 weeks.
  • Thought: every paper has a different method for quantify immune response, GFAP staining in this case.

{1189}
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ref: -0 tags: microelectrode array flexible PDMS via interconnect Georgia date: 01-04-2013 00:33 gmt revision:0 [head]

IEEE-6197244 (pdf) A PDMS-Based Integrated Stretchable Microelectrode Array (isMEA) for Neural and Muscular Surface Interfacing

  • Targeted at e.g. ECoG; in this paper, they look at cat muscle (epimyscial recording).
  • MEA is directly fabricated with a stretchable substrate, such as a thin PCB or ASIC, through via bonding for built-in packaging.

{1188}
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ref: -0 tags: flexible micxrowire arrays electrode recording Georgia polymide date: 01-04-2013 00:13 gmt revision:1 [0] [head]

IEEE-906517 (pdf) Flexible microelectrode arrays with integrated insertion devices

  • 2001 MEMS Conference.
  • FMA = flexible microelectrode arrays.
  • Both for nerves (pass-through needle) and cortex (removeable needle).
    • Primarily tested in tissue proxies.
  • Anticipated the utility of photolithography for patterning the electrodes + rigid insertion devices.
  • The elastic modulus of polymers like polymide are two orders of magnitude less than metals, but still six orders of magnitude higher than brain tissue (46kPa).
  • Pass-through needle very similar to the threaded wire idea.
  • removable needle simply stops the thread & drives the needle a bit further to break the attachment site.
    • Did not test removable needle technique (?)
  • Defined electroplating with a thick photoresist mask, as Michel says.
  • Tested FMAs with movement and acceleration vs. rigid arrays. FMAs faired much better, of course!

____References____

' ''' ()

{1165}
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ref: -0 tags: Moxon ceramic array electrode lithography date: 07-12-2012 23:05 gmt revision:3 [2] [1] [0] [head]

IEEE-1275580 (pdf) Ceramic-based Multisite Electrode array for Chronic Single-Neuron Recording

  • Their substrate is polished to 35-50um thick
  • patterned using standard lift-off lithographic techniques
  • four electrodes per shank
  • The ceramic is considerably stiffer than silicon (table) -- 372 Gpa vs. 190 Gpa.

{923}
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ref: Freire-2011.01 tags: Nicolelis BMI electrodes immune respones immunohistochemistry chronic arrays rats 2011 MEA histology date: 06-29-2012 01:20 gmt revision:5 [4] [3] [2] [1] [0] [head]

PMID-22096594[0] Comprehensive analysis of tissue preservation and recording quality from chronic multielectrode implants.

  • Says what might be expected: tungsten microelectrode arrays work, though the quality gradually declines over 6 months.
  • Histological markers correlated well with recording performance.
  • Shows persistent glial activation around electrode sites + cell body hypertropy.
    • Suggest that loss in recording quality may be due to glial encapsulation.
  • References
    • Szarowski et al 2003 {1028}
    • Ward et al 2009
  • Histology:
    • NADPH-d: nicotinamide adenine dinucleotide phosphate-diaphorase, via beta-NADP
    • CO: cytochrome oxidase, via diamnibenzidine DAB, cytochrome c and catalase.
      • both good for staining cortical layers; applied in a standard buffered solution and monitored to prevent overstaining.
  • Immunohistochemistry:
    • Activated microglia with ED-1 antibody.
    • Astrocytes labeled with glial fibrillary acid protein.
    • IEG with an antibody against EGR-1, 'a well-known marker of calcium dependent neuronal activity'
    • Neurofilament revealed using a monoclonal NF-M antibody.
    • Caspace-3 with the associated antibody
    • Details the steps for immunostaining -- wash, blocknig buffer, addition of the antibody in diluted blocking solution (skim milk) overnight, wash again, incubate in biotinylated secondary antibody, wash again, incubate in avidin-biotin-peroxidase solution.
    • Flourescent immunohistochemistry had biotynlation replaced with alexa Fluor 488-conjugated horse anti-mouse and Alexa Fluor 594-conjugated goat anti-rabbit overnight.

____References____

[0] Freire MA, Morya E, Faber J, Santos JR, Guimaraes JS, Lemos NA, Sameshima K, Pereira A, Ribeiro S, Nicolelis MA, Comprehensive analysis of tissue preservation and recording quality from chronic multielectrode implants.PLoS One 6:11, e27554 (2011)

{1056}
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ref: Nordhausen-1996.07 tags: Normann Utah array recording date: 02-06-2012 21:37 gmt revision:3 [2] [1] [0] [head]

PMID-8836553[0] Single unit recording capabilities of a 100 microelectrode array. Nordhausen CT, Maynard EM, Normann RA.

  • Used the Utah array in visual stimulus-evoked response in cats.
  • 58.6% of electrodes in the array recorded neural activity.
  • The density of the electrodes in the UIEA makes it impossible to simply push the needles into the cortex with forceps. This only results in surface dimpling, incomplete insertion, and possible cortical damage.
    • We have instead designed a high speed pneumatic insertion tool which takes advantage of viscoelectric properties of the cortical tissue by advancing the electrodes into the tissue at very high velocity.

____References____

[0] Nordhausen CT, Maynard EM, Normann RA, Single unit recording capabilities of a 100 microelectrode array.Brain Res 726:1-2, 129-40 (1996 Jul 8)

{1025}
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ref: Hoogerwerf-1994.12 tags: Wise Michigan array MEA recording 3D date: 01-15-2012 07:12 gmt revision:4 [3] [2] [1] [0] [head]

IEEE-335862 (pdf) A three-dimensional microelectrode array for chronic neural recording.

  • see {995} for reasonable photos (they don't show up in the black and white IEEE scan).
  • 16-channel, 4 shanks.
  • 3D : 16 shanks, 64 channels, includes a 16:1 MNOS mux on the attached micromachined silicon platform.
  • Nickel plated lead stransfers (90 deg) see figure 6 electroplating current.
    • This was a point of difficulty, it seems.

____References____

Hoogerwerf, A.C. and Wise, K.D. A three-dimensional microelectrode array for chronic neural recording Biomedical Engineering, IEEE Transactions on 41 12 1136 -1146 (1994)

{997}
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ref: Najafi-1985.07 tags: Najafi original silicon michigan recording array 1985 MEA date: 01-06-2012 05:27 gmt revision:10 [9] [8] [7] [6] [5] [4] [head]

IEEE-1484848 (pdf) A high-yield IC-compatible multielectrode recording array.

  • Already talks about closed-loop control of a neuroprosthesis.
  • Started testing on-chip NMOS amplifiers.
  • tantalum and polysilicon conductors. some resistivity, but much less than the electrode interface.

____References____

Najafi, K. and Wise, K.D. and Mochizuki, T. A high-yield IC-compatible multichannel recording array Electron Devices, IEEE Transactions on 32 7 1206 - 1211 (1985)

{309}
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ref: Porada-2000.01 tags: electrodes recording oblique inverted MEA arrays Kruger date: 01-05-2012 23:07 gmt revision:3 [2] [1] [0] [head]

PMID-10776811[0] More than a year of recording with up to 64 microelectrodes

  • for more than a year action potentials of good quality were obtained from most electrodes!
  • used 60mm-long, 12.5um Ni-Cr-Al (Isaohm) wire, polyimide insulated, soldered to microconnectors. Tips purely ('primitively') cut after bonding them to a piece of photographic film substrate.
  • implanted in the rabbit and marmoset V1 cortex from afar.
  • with the 8 rabbits they used a magnetic release to prevent excessive force from removing the implant.
  • used small sections of thicker wire to individually label the electrodes for x-ray; thusly could reconstruct the electrode positions. electrodes in the white matter were silent mais or menos.
  • the autocorrelation functions of the neurons generally look good; some of them do not have a refractory period though.
  • in GFAP-stained sections a single electrode track appeared as a hole of about 28 um wide. The outer diameter of the wire insulation as 18um. electrode tracts were not visible in cresyl violet tracts. the neurones near the electrode tips appeared normal.
  • we recorded signals for up to 711 days, during which time the recording quality did not degrade. nice, nice!
  • they think that the large length of free wire, running about 5mm through the brain provides a sufficient degree of friction so that locally the tissue is prevented from moving relative to the electrodes. They did not need to use microstimulation to improve recording quality.

____References____

{925}
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ref: Nicolelis-1997 tags: nicolelis microwire array electrophysiology rats date: 01-05-2012 03:35 gmt revision:2 [1] [0] [head]

PMID-9136763[0] Reconstructing the engram: simultaneous, multisite, many single neuron recordings.

  • descibes Miguel's microwire arrays.
  • 100 units from 48 microwires in rats.
  • 2.3 units / microwire.
  • stable for weeks -- c.f. 2011. [1]

____References____

[0] Nicolelis MA, Ghazanfar AA, Faggin BM, Votaw S, Oliveira LM, Reconstructing the engram: simultaneous, multisite, many single neuron recordings.Neuron 18:4, 529-37 (1997 Apr)
[1] Freire MA, Morya E, Faber J, Santos JR, Guimaraes JS, Lemos NA, Sameshima K, Pereira A, Ribeiro S, Nicolelis MA, Comprehensive analysis of tissue preservation and recording quality from chronic multielectrode implants.PLoS One 6:11, e27554 (2011)

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ref: Najafi-1986.12 tags: Najafi implantable wired recording Michigan array multiplexing silicon boron MEA date: 01-05-2012 03:07 gmt revision:8 [7] [6] [5] [4] [3] [2] [head]

IEEE-1052646 (pdf) An implantable multielectrode array with on-chip signal processing

  • "The major reason for the slow progress in the understanding of neural circuits has been the lack of adequate instrumentation."
  • previous photolithographic: [4],[5]. Their first publication: [7].
  • Kensall Wise, not Stephen.
  • Single shank
  • 10 recording sites spaced at 100um
  • Amplifying 100x, b/w 15kHz., multiplexing.
  • width: 15um near tip, 160um at base.
  • 3 leads (!) power, ground, data.
  • 6um LOCOS enhancement and depletion NMOS technology -- not CMOS. (latter is prone to latch-up)
  • 5mW power.
  • boron dope silicon, etch back non doped portion with ethylenediamine-pyrocatechol (EDP) water solution.
  • must not have any substrate bias!

____References____

Najafi, K. and Wise, K.D. An implantable multielectrode array with on-chip signal processing Solid-State Circuits, IEEE Journal of 21 6 1035 - 1044 (1986)

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ref: Verloop-1984.08 tags: recording electrode arrays MEA epoxy teflon simple mold slice cultures date: 01-03-2012 00:57 gmt revision:2 [1] [0] [head]

PMID-6492861[0] A simple method for the construction of electrode arrays.

  • It is simple!
  • of note: "Therefore arrays of equidistant electrodes have been developed for superficial and depth recording. During the last decade the construction of many of these multiple electrodes for in vivo and in vitro measurements is based o n thin film techniques (Wise a n d Angell, 1975; Pickard, 1979; Pochay et al., 1979; Prohaska et al., 1979; Kuperstein and Whittington, 1981).
    • Have to go back and check these thin-film attempts.
  • See also: PMID-7248818[1] A flexible high density multi-channel electrode array for long-term chronic implantation. (surface recording).

____References____

[0] Verloop AJ, Holsheimer J, A simple method for the construction of electrode arrays.J Neurosci Methods 11:3, 173-8 (1984 Aug)
[1] Weissman AD, Schwartz EL, A flexible high density multi-channel electrode array for long-term chronic implantation.Brain Res Bull 6:6, 543-6 (1981 Jun)

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ref: Wilson-1993.08 tags: Wilson McNaughton 1993 sleep hippocampus array recording date: 01-03-2012 00:57 gmt revision:2 [1] [0] [head]

PMID-8351520[0] Dynamics of the hippocampal ensemble code for space.

  • 73-148 neurons.
  • Could accurately decode the rat's movement through space.
  • "The parallel recording methods outlined here make possible the study of the dynamics of neuronal interactions during unique behavioral events."

PMID-8036517[1] Reactivation of hippocampal ensemble memories during sleep.

  • "Information acquired during active behavior is thus re-expressed in hippocampal circuits during sleep, as postulated by some theories of memory consolidation."

____References____

[0] Wilson MA, McNaughton BL, Dynamics of the hippocampal ensemble code for space.Science 261:5124, 1055-8 (1993 Aug 20)
[1] Wilson MA, McNaughton BL, Reactivation of hippocampal ensemble memories during sleep.Science 265:5172, 676-9 (1994 Jul 29)

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ref: Nicolelis-1998.11 tags: spatiotemporal spiking nicolelis somatosensory tactile S1 3b microwire array rate temporal coding code date: 12-28-2011 20:42 gmt revision:3 [2] [1] [0] [head]

PMID-10196571[0] Simultaneous encoding of tactile information by three primate cortical areas

  • owl monkeys.
  • used microwires arrays to decode the location of tactile stimuli; location was encoded through te population, not within single units.
  • areas 3b, S1 & S2.
  • used LVQ (learning vector quantization) backprop, LDA to predict/ classify touch trials; all yielded about the same ~60% accuracy. Chance level 33%.
  • Interesting: "the spatiotemporal character of neuronal responses in the SII cortex was shown to contain the requisite information for the encoding of stimulus location using temporally patterned spike sequences, whereas the simultaneously recorded neuronal responses in areas 3b and 2 contained the requisite information for rate coding."
    • They support this result by varying bin widths and looking at the % of correctly classivied trials. in SII, increasing bin width decreases (slightly but significantly) the prediction accuracy.

____References____

[0] Nicolelis MA, Ghazanfar AA, Stambaugh CR, Oliveira LM, Laubach M, Chapin JK, Nelson RJ, Kaas JH, Simultaneous encoding of tactile information by three primate cortical areas.Nat Neurosci 1:7, 621-30 (1998 Nov)

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ref: Serruya-2002.03 tags: BMI Donoghue 2002 Hatsopoulos Utah array Serruya date: 09-07-2008 19:08 gmt revision:1 [0] [head]

PMID-11894084[0] Instant neural control of a movement signal.

  • used only a few (7-30) motor cortex neurons
  • this let the monkey immediately manipulate a computer cursor, without extensive training (according to them).

____References____