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| Creator | Title | Description | Subject | Date | ||
|---|---|---|---|---|---|---|
| 1 |
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Normann, Richard A. | Control of retinal sensitivity. I. Light and dark adaptation of vertebrate rods and cones | 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 Cells | 1974 |
| 2 |
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Normann, Richard A. | Effects of background illumination on the photoresponses of red and green cones | 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 Transmission | 1979 |
| 3 |
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Normann, Richard A.; Chandler, John P. | Effects of calcium ions on L-type horizontal cells in the isolated turtle retina | 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; Turtle | 1990 |
| 4 |
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Normann, Richard A. | Effects of GABA and related drugs on horizontal cells in the isolated turtle retina | 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; Turtle | 1990 |
| 5 |
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Normann, Richard A.; Horch, Kenneth W.; Cha, Kichul | Mobility performance with a pixelized vision system | A 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 Simulator | 1992 |
| 6 |
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Normann, Richard A.; Kolb, Helga | Neural organization of the retina of the turtle Mauremys caspica: a light microscope and Golgi study | The 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 Cells | 1988 |
| 7 |
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Normann, Richard A. | Oscillations in rod and horizontal cell membrane potential: evidence for feed-back to rods in the vertebrate retina | 1. 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, Ocular | 1976 |
| 8 |
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Normann, Richard A.; Kolb, Helga; Lasater, Eric M. | Signal integration at the pedicle of turtle cone photoreceptors: an anatomical and electrophysiological study | 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 Coupling | 1989 |
| 9 |
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Normann, Richard A. | Signal transmission from red cones to horizontal cells in the turtle retina | 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; Photoreceptors | 1979 |
| 10 |
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Normann, Richard A.; Abbasi, Masoud; Johansson,Torbjorn | Silicon carbide enhanced thermomigration | The 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 Lamps | 1992 |
| 11 |
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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 array | 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 Array | 1991 |
| 12 |
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Normann, Richard A.; Muller, Jay F.; Kolb, Helga | Synaptic inputs to physiologically defined turtle retinal ganglion cells | Two 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 Cells | 1991 |
| 13 |
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Normann, Richard A.; Johansson,Torbjorn; Abbasi, Masoud; Huber, Robert J. | Three-dimensional architecture for a parallel processing photosensing array | 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; Photosensing | 1992 |
| 14 |
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Normann, Richard A. | Visual Neuroprosthetics: Functional Vision for the Blind | 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; Blindness | 1995-01 |
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