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1 Normann, Richard A.Oscillations in rod and horizontal cell membrane potential: evidence for feed-back to rods in the vertebrate retina1. Rods and horizontal cells were studied with intracellular recordings in the retina of the toad, Bufo marinus; 161 cells were from the eyecup preparation and thirty were from the isolated perfused retina. 2. Of these cells, 39% exhibited either transient or sustained oscillations of membrane poten...Retina; Photoreceptors; Toads; Adaptation, Ocular1976
2 Normann, Richard A.; Campbell, Patrick K.; Jones, Kelly E.; Huber, Robert J.; Horch, Kenneth W.Silicon-based, three-dimensional neural interface: manufacturing processes for an intracortical electrode arrayA 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
3 Normann, Richard A.Effects of GABA and related drugs on horizontal cells in the isolated turtle retinaThe 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
4 Normann, Richard A.; Abbasi, Masoud; Johansson,TorbjornSilicon carbide enhanced thermomigrationThe widespread acceptance of thermomigration technology to produce through-chip interconnects has been impaired by (i) a random walk of the Si-Al liquid eutectic inclusion as it traverses the wafer, and (ii) a ?surface barrier? which allows thermomigration of only relatively large inclusions. In ...Silicon Dioxide; Thermometers; Transducers; Thermomigration Technology; Infrared Lamps1992
5 Normann, Richard A.; Muller, Jay F.; Kolb, HelgaSynaptic inputs to physiologically defined turtle retinal ganglion cellsTwo 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
6 Edelman, Linda S.Dangerous spaces: Using geographic information systems in injury researchPURPOSE: To provide an overview of geographic information systems (GIS) and to discuss current and future applications in injury and trauma research. DESIGN: Literature review and discourse of GIS technology related to injury and trauma research. METHOD: A search of scientific literature databases, ...Community; Public Health; Technology; Internet; Risk Assessment; Wounds and Injuries2007-08
7 Normann, Richard A.; Shah, Maulik R.Study of printed spiral coils for neuroprosthetic transcranial telemetry applicationsWe 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
8 Normann, Richard A.; Johansson,Torbjorn; Abbasi, Masoud; Huber, Robert J.Three-dimensional architecture for a parallel processing photosensing arrayA 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
9 Normann, Richard A.; Jones, Kelly E.Advanced demultiplexing system for physiological stimulationA 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
10 Normann, Richard A.Statistical encoding model for a primary motor cortical brain-computer interfaceA 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
11 Normann, Richard A.; Chandler, John P.Effects of calcium ions on L-type horizontal cells in the isolated turtle retinaA 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
12 Normann, Richard A.Signal transmission from red cones to horizontal cells in the turtle retina1. 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
13 Aldous, Jay A.; Engar, Richard C.Do dentists prescribe narcotics excessively?Dealing with pain is an inevitable sequela to dental treatment. Although several drug regimens primarily involving narcotics have been used in the past, availability of nonsteroidal anti-inflammatory drugs (NSAIDs) has increased recently. A study was conducted to analyze dental prescribing patterns ...Analgesics, Opioid; Anti-Inflammatory Agents; Dentist's Practice Patterns; Pain, Postoperative1996-07-01
14 Normann, Richard A.; Clark, Gregory A.; McDonnall, DanielSelective motor unit recruitment via intrafascicular multielectrode stimulationRecruitment 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
15 Normann, Richard A.; Campbell, Patrick K.; Jones, Kelly E.100 electrode intracortical array: structural variabilityA technique has been developed for fabricating three dimensional "hair brush" electrode arrays from monocrystalline silicon blocks. Arrays consist of a square pattern of 100 penetrating electrodes, with 400 microns interelectrode spacing. Each electrode is 1.5mm in length and tapers from about 100 m...Microelectrode arrays; Stimulation; Micromachining1990
16 Normann, Richard A.; Shoham, ShyCoding of position by simultaneously recorded sensory neurones in the cat dorsal root ganglionMuscle, 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
17 Normann, Richard A.Control of retinal sensitivity. I. Light and dark adaptation of vertebrate rods and conesRods 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
18 Normann, Richard A.; Shoham, ShyEncoding mechanisms for sensory neurons studied with a multielectrode array in the cat dorsal root ganglionRecent 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
19 Normann, Richard A.; Maynard, Edwin M.Neuronal interactions improve cortical population coding of movement directionInteractions 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
20 Normann, Richard A.Effects of background illumination on the photoresponses of red and green cones1. 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
21 Normann, Richard A.; Horch, Kenneth W.; Cha, KichulMobility performance with a pixelized vision systemA 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
22 Normann, Richard A.Functional reorganization of primary visual cortex induced by electrical stimulation in the cat.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
23 Normann, Richard A.Visual Neuroprosthetics: Functional Vision for the BlindResent 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
24 Normann, Richard A.; Kolb, Helga; Lasater, Eric M.Signal integration at the pedicle of turtle cone photoreceptors: an anatomical and electrophysiological studyThe 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
25 Normann, Richard A.; Branner, AlmutLong-term stimulation and recording with a penetrating microelectrode array in cat sciatic nerveWe 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
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