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TitleCreatorDescriptionSubjectDate
1Silicon-based, three-dimensional neural interface: manufacturing processes for an intracortical electrode arraySilicon-based, three-dimensional neural interface: manufacturing processes for an intracortical electrode arrayNormann, Richard A.; Campbell, Patrick K.; Jones, Kelly E.; Huber, Robert J.; Horch, Kenneth W.A method has been developed for the manufacture of a "three-dimensional" electrode array geometry for chronic intracortical stimulation. This silicon based array consists of a 4.2 x 4.2 x 0.12 mm thick monocrystalline substrate, from which project 100 conductive, silicon needles sharpened to facilit...Electric Stimulation; Electrodes, Implanted; Sensory Cortex; Intracortical Electrode Array1991
2Mobility performance with a pixelized vision systemMobility performance with a pixelized vision systemNormann, Richard A.; Horch, Kenneth W.; Cha, KichulA visual prosthesis, based on electrical stimulation of the visual cortex, has been suggested as a means for partially restoring functional vision in the blind. The prosthesis would create a pixelized visual sense consisting of punctate spots of light (phosphenes). The present study investigated the...Visual Prosthesis; Mobility; Phosphene Simulator1992
3Signal integration at the pedicle of turtle cone photoreceptors: an anatomical and electrophysiological studySignal integration at the pedicle of turtle cone photoreceptors: an anatomical and electrophysiological studyNormann, Richard A.; Kolb, Helga; Lasater, Eric M.The morphology of the axon which connects the cell body and pedicle of turtle cone photoreceptors was studied by light and electron microscopy. The axon which contains numerous synaptic vesicles, some endoplasmic reticulum, and a few cisternae is basically filled with cytoplasm. The length of the ax...Cone Photoreceptor, Voltage Clamp; Isolated Cells; Input Resistance; Cell Body-Pedicle Coupling1989
4Functional reorganization of primary visual cortex induced by electrical stimulation in the cat.Functional reorganization of primary visual cortex induced by electrical stimulation in the cat.Normann, Richard A.Compared to the high degree of plasticity observed in a juvenile, mature sensory cortices have long been held to be immutable but, recently, researchers have suggested some plasticity persists in the mature cortex. Cortical reorganization has particular saliency to the development of a cortically ba...Cat; Electrophysiology; Phosphene; Plasticity; Receptive Field; Striate Cortex2005
5Encoding mechanisms for sensory neurons studied with a multielectrode array in the cat dorsal root ganglionEncoding mechanisms for sensory neurons studied with a multielectrode array in the cat dorsal root ganglionNormann, Richard A.; Shoham, ShyRecent advances in microelectrode array technology now permit a direct examination of the way populations of sensory neurons encode information about a limb's position in space. To address this issue, we recorded nerve impulses from about 100 single units simultaneously in the L6 and L7 dorsal root ...Sensory; Encoding; Multielectrode; Dorsal Root Ganglion; Cutaneour; Muscle2004
6Three-dimensional architecture for a parallel processing photosensing arrayThree-dimensional architecture for a parallel processing photosensing arrayNormann, Richard A.; Johansson,Torbjorn; Abbasi, Masoud; Huber, Robert J.A three-dimensional architecture for a photosensing array has been developed. This silicon based architecture consists of a 10 x 10 array of photosensors with 80 microns diameter, through chip interconnects to the back side of a 500 microns thick silicon wafer. Each photosensor consists of a 300 x 3...Retina; Optics; Silicon; Photosensing1992
7Neural interface for a cortical vision prosthesisNeural interface for a cortical vision prosthesisNormann, Richard A.; Maynard, Edwin M.The development of a cortically based vision prosthesis has been hampered by a lack of basic experiments on phosphene psychophysics. This basic research has been hampered by the lack of a means to safely stimulate large numbers of cortical neurons. Recently, a number of laboratories have developed a...Neuroprosthetics; Artificial Vision; Electrode Arrays; Multielectrode Recordings; Biocompatibility1999
8Selective motor unit recruitment via intrafascicular multielectrode stimulationSelective motor unit recruitment via intrafascicular multielectrode stimulationNormann, Richard A.; Clark, Gregory A.; McDonnall, DanielRecruitment of force via independent asynchronous firing of large numbers of motor units produces the grace and endurance of physiological motion. We have investigated the possibility of reproducing this physiological recruitment strategy by determining the selectivity of access to large numbers of ...Funtional Neuromuscular Stimulation; Microelectrode Array; Neuroprosthesis; Intrafascicular Multielectrode Stimulation; Cats2004
9Effects of GABA and related drugs on horizontal cells in the isolated turtle retinaEffects of GABA and related drugs on horizontal cells in the isolated turtle retinaNormann, Richard A.The role of GABA in the outer plexiform layer of the turtle retina has been examined by intracellular recordings from L- and C-type horizontal cells in the isolated retina preparation. GABA (1-5 mM) slightly depolarized the L-type horizontal cells, reduced the amplitude of their photoresponses, and ...Retina; Horizontal Cells; Synapse; Negative Feedback; GABA; Turtle1990
10Gut endoderm is involved in the transfer of left-right asymmetry from the node to the lateral plate mesoderm in the mouse embryoGut endoderm is involved in the transfer of left-right asymmetry from the node to the lateral plate mesoderm in the mouse embryoLucero, Mary T.2012-01-01
11Evidence for multiple signaling pathways in single squid olfactory receptor neuronsEvidence for multiple signaling pathways in single squid olfactory receptor neuronsLucero, Mary T.; Mobley, Arie S.; Mahendra, GandhamAt least two different G-protein-mediated transduction cascades, the adenylate cyclase and phospholipase C (PLC) pathway, process chemosensory stimuli for various species. In squid olfactory receptor neurons (ORNs), physiological studies indicate that both pathways may be present; however, confirmat...Olfaction; Cephalopods; G Proteins, PLC; Adenylate Cyclase2007-03
12Synaptic inputs to physiologically defined turtle retinal ganglion cellsSynaptic inputs to physiologically defined turtle retinal ganglion cellsNormann, Richard A.; Muller, Jay F.; Kolb, HelgaTwo physiologically distinct, HRP-marked turtle retinal ganglion cells were examined for their morphology, GABAergic, glycinergic, and bipolar cell synaptic inputs, using electron-microscopic autoradiography and postembedding immunocytochemistry. One cell was a color-opponent, transient ON/OFF gangl...Turtles; Neural Pathways; Synapes; Retinal Ganglion Cells1991
13Study of printed spiral coils for neuroprosthetic transcranial telemetry applicationsStudy of printed spiral coils for neuroprosthetic transcranial telemetry applicationsNormann, Richard A.; Shah, Maulik R.We have explored the use of printed spiral coils (PSC's) for neuroprosthetic transcranial telemetry applications. We fabricated two-dimensional PSC's on a thin (25 microns) polyimide substrate using copper (35 microns) as a conducting material. All the coils had a fixed inner diameter of 1.0 cm. We ...Blindness; Neuroprosthesis; Transcranial Telemetry System; Prosthesis Design1998
14Long-term stimulation and recording with a penetrating microelectrode array in cat sciatic nerveLong-term stimulation and recording with a penetrating microelectrode array in cat sciatic nerveNormann, Richard A.; Branner, AlmutWe studied the consequences of long-term implantation of a penetrating microelectrode array in peripheral nerve over the time course of 4-6 mo. Electrode arrays without lead wires were implanted to test the ability of different containment systems to protect the array and nerve during contractions o...Cats; Microelectrodes; Prosthesis Implantation; Sciatic Nerve2004
15Neural organization of the retina of the turtle Mauremys caspica: a light microscope and Golgi studyNeural organization of the retina of the turtle Mauremys caspica: a light microscope and Golgi studyNormann, Richard A.; Kolb, HelgaThe organization of the retina of the turtle species Mauremys caspica, found in fresh water ponds of Israel, has been examined by light microscopical techniques including examination of fresh wholemount retina, one micron blue-stained vertical sections and Golgi-stained material. The anatomical find...Turtle Retina; Photoreceptors; Golgi Technique; Amarcine Cells1988
16Neuronal interactions improve cortical population coding of movement directionNeuronal interactions improve cortical population coding of movement directionNormann, Richard A.; Maynard, Edwin M.Interactions among groups of neurons in primary motor cortex (MI) may convey information about motor behavior. We investigated the information carried by interactions in MI of macaque monkeys using a novel multielectrode array to record simultaneously from 12-16 neurons during an arm-reaching task. ...Motor Cortex; Monkey; Population Coding; Movement1999
17Effects of background illumination on the photoresponses of red and green conesEffects of background illumination on the photoresponses of red and green conesNormann, Richard A.1. The photoresponses of light- and dark-adapted red and green cone photoreceptors were recorded intracellularly in the retina of the turtle, Pseduemys scripta elegans. Background illumination produced similar effects on both types of cones. 2. In response to the onset of a prolonged, steady backgro...Turtles; Adaptation, Ocular; Retina; Signal Transmission1979
18Advanced demultiplexing system for physiological stimulationAdvanced demultiplexing system for physiological stimulationNormann, Richard A.; Jones, Kelly E.A CMOS very large scale integration (VLSI) chip has been designed and built to implement a scheme developed for multiplexing/demultiplexing the signals required to operate an intracortical stimulating electrode array. Because the use of radio telemetry in a proposed system utilizing this chip may im...Electrode Array; Stimulation; Telemetry; Microelectrodes; Transistors1997
19Control of retinal sensitivity. I. Light and dark adaptation of vertebrate rods and conesControl of retinal sensitivity. I. Light and dark adaptation of vertebrate rods and conesNormann, Richard A.Rods and cones in Necturus respond with graded hyperpolarization to test flashes spanning about 3.5 log units of intensity. Steady background levels hyperpolarize the rods, and the rod responses become progressively smaller as background level is increased. In cones, higher background levels reduce...Retina;Light and Dark Adaptation; Recepters; Bipolars; Ganglion Cells1974
20Effects of calcium ions on L-type horizontal cells in the isolated turtle retinaEffects of calcium ions on L-type horizontal cells in the isolated turtle retinaNormann, Richard A.; Chandler, John P.A technique by which the retina can be isolated from the turtle eye is described. Scanning electron microscopy revealed morphological variability between preparations and also between regions of the same one. Large areas were often totally free of any pigment epithelial cells, yet contained a high p...Retina; Calcium; Horizontal Cell; Turtle1990
21Signal transmission from red cones to horizontal cells in the turtle retinaSignal transmission from red cones to horizontal cells in the turtle retinaNormann, Richard A.1. Intracellular recordings were made from L-type horizontal cells in the retina of the turtle Pseudemys scripta elegans. The responses were evoked by 500 msec pulses of 'white' light. 2. L-type horizontal cells were classified as either, 'small receptive field' s.r.f. or 'large receptive field' l.r...Turtles; Synapses; Retina; Photoreceptors1979
22Cross-species comparison of metabolite profiles in chemosensory epithelia: an indication of metabolite roles in chemosensory cellsCross-species comparison of metabolite profiles in chemosensory epithelia: an indication of metabolite roles in chemosensory cellsLucero, Mary T.; Mobley, Arie S.Comparative studies of chemosensory systems in vertebrates and invertebrates have greatly enhanced our understanding of anatomical and physiological constraints of chemical detection. Immunohistochemical comparisons of chemosensory systems are difficult to make across species due to limited cross-re...Olfactory; Vomeronasal; Mouse; Zebrafish; Squid2008-04
23Statistical encoding model for a primary motor cortical brain-computer interfaceStatistical encoding model for a primary motor cortical brain-computer interfaceNormann, Richard A.A number of studies of the motor system suggest that the majority of primary motor cortical neurons represent simple movement-related kinematic and dynamic quantities in their time-varying activity patterns. An example of such an encoding relationship is the cosine tuning of firing rate with respect...Discrete Distribution; LN Model; Neural Decoding; Neuroprosthetics; Sequential Monte-Carlo Filter2005
24Coding of position by simultaneously recorded sensory neurones in the cat dorsal root ganglionCoding of position by simultaneously recorded sensory neurones in the cat dorsal root ganglionNormann, Richard A.; Shoham, ShyMuscle, cutaneous and joint afferents continuously signal information about the position and movement of individual joints. How does the nervous system extract more global information, for example about the position of the foot in space? To study this question we used microelectrode arrays to record...Cats; Sensory Neurones; Movement; Limb Position2004
25Visual Neuroprosthetics: Functional Vision for the BlindVisual Neuroprosthetics: Functional Vision for the BlindNormann, Richard A.Resent progress in materials and microfabrication technologies have allowed researchers to reconsider the prospect of providing a useful visual sense to the profoundly blind. This will be accomplished by electrically stimulating their visual systems via an array of implanted microelectrodes. T...Visual Neuroprosthetics; Vision; Blindness1995-01
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