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CreatorTitleDescriptionSubjectDate
1 Normann, Richard A.; Maynard, Edwin M.Neural interface for a cortical vision prosthesisThe 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
2 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
3 Angelucci, Alessandra; Lund, Jennifer S.Circuits for local and global signal integration in primary visual cortexContrast-dependent changes in spatial summation and contextual modulation of primary visual cortex (V1) neuron responses to stimulation of their receptive field reveal long-distance integration of visual signals within V1, well beyond the classical receptive field (cRF) of single neurons. To identif...Primary Visual Cortex; Extrastriate Cortex; Feed-back Connections; Lateral Connections; SUrround Modulation; Macaque2002-10-01
4 Angelucci, AlessandraMultiple components of surround modulation in primary visual cortex: Multiple neural circuits with multiple functions?The responses of neurons in primary visual cortex (V1) to stimulation of their receptive field (RF) are modulated by stimuli in the RF surround. This modulation is suppressive when the stimuli in the RF and surround are of similar orientation, but less suppressive or facilitatory when they are cross...2014-01-01
5 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
6 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
7 Angelucci, AlessandraLayer-specific programs of development in neocortical projection neuronsHow are long-range axonal projections from the cerebral cortex orchestrated during development? By using both passively and actively transported axonal tracers in fetal and postnatal ferrets, we have analyzed the development of projections from the cortex to a number of thalamic nuclei. We report th...Axonal Transport; Efferent Pathways; Brain Mapping1995
8 Angelucci, AlessandraSegregation and overlap of callosal and association neurons in frontal and parietal cortices of primates: a spectral and coherency analysis.The spatial relations between selected classes of association and callosal neurons were studied in the frontal and parietal lobes of the macaque monkey using retrogradely transported fluorescent dyes. Fast blue and nuclear yellow were injected in the left frontal (areas 4 and 6) and right posterior ...Macaca fascicularis; Parietal Lobe; Neurons1989
9 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
10 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
11 Digre, Kathleen B.; Couldwell, William T.; Amini, AminPhotophobia in a blind patient: An alternate visual pathway. Case report.Photophobia is a common neurological and ophthalmological symptom that has been associated with a growing number of neurosurgical conditions, especially compressive lesions. The exact signaling pathways and neurophysiological features of the disorder are not well understood; however, data from multi...Photophobia, Blindness, Signaling Pathway, Pretectal Nuclei, Trigeminal Pathway2006-12-14
12 Olson, Randall J.Clinical experience with 21-gauge manual microphacoemulsification using Sovereign WhiteStar Technology in eyes with dense cataractPURPOSE: To present a series of patients who had 21-gauge microphacoemulsification using Sovereign WhiteStar technology. SETTING: John A. Moran Eye Center, University of Utah School of Medicine, Salt Lake City, Utah, USA. METHODS: Eighteen consecutive patients with cataracts judged to be 3+ or 4+ on...Cataract; Microsurgery; Phacoemulsification; Postoperative Complications; Visual Acuity2004-01
13 Olson, Randall J.; Coldwell, Karin D.; Compton, Bruce J.; Giddings, John C.Sedimentation field-flow fractionation: a method for studying particulates in cataractous lensIt is shown that the technique of sedimentation field-flow fractionation (sedimentation [sed] FFF) can be used to determine the particle content and particle size distribution of normal and cataractous lenses. A 31-year-old normal human lens, for example, showed a particle content of 1.5% by weight ...Fractionation; Cataractous Lens; Particulates1984
14 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
15 Digre, Kathleen B.; Skuster, Denise Z.Neurologic conditions presenting as psychiatric disorders.Understanding underlying neuroanatomic function helps physicians to localize defects and search for treatable neurologic conditions. Neurologic conditions such as Huntington's chorea, Wilson's disease, Gille de la Tourette syndrome, brain tumors, encephalitis and meningitis, neurodegenerative condit...Psychiatric Diagnosis; Neurologic Disease1992-06-15
16 Angelucci, AlessandraExperimentally induced retinal projections to the ferret auditory thalamus: development of clustered eye-specific patterns in a novel targetWe have examined the relative role of afferents and targets in pattern formation using a novel preparation, in which retinal projections in ferrets are induced to innervate the medial geniculate nucleus (MGN). We find that retinal projections to the MGN are arranged in scattered clusters. Clusters a...Retina; Ferrets1997
17 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
18 Angelucci, AlessandraRole for nitric oxide in the development of the ferret retinogeniculate projectionThe ferret retinogeniculate projection segregates into eye-specific layers during the first postnatal week and into ON/OFF sublaminae, which receive inputs from either on-center or off-center retinal ganglion cells, during the third and fourth postnatal weeks. The restriction of retinogeniculate axo...Enzyme Inhibitors; Visual Pathways; Wheat Germ Agglutinin-Horseradish Peroxidase Conjugate1996
19 Crandall, Alan S.Torn posterior capsule: prevention, recognition and managementModern cataract surgery performed with phacoemulsification allows meticulous intraocular control and minimal incision size, but has the inherent risk of capsular rupture. Therefore, surgeons performing cataract surgery will inevitably face the complication of a torn posterior capsule. Torn posteri...Capsulorrhexis complications; Phacoemulsification; Posterior capsular tears; Shallow anterior chamber; Suprachoroidal hemorrhage; Vitrectomy1999
20 Olson, Randall J.Clinical comparison of single-piece and three-piece truncated hydrophobic acrylic intraocular lensesPURPOSE: To determine the clinical differences between three-piece (3P) and single-piece (SP) truncated hydrophobic acrylic intraocular lenses (IOL). DESIGN: Retrospective cohort clinical study. METHODS: The setting was an academic clinical practice. The patient population consisted of subjects with...Lenses, Intraocular; Patient Satisfaction; Postoperative Complications; Prosthesis Design; Visual Acuity2003-10
21 Baehr, WolfgangTissue-specific expression in transgenic mice directed by the 5'-flanking sequences of the human gene encoding interphotoreceptor retinoid-binding proteinInterphotoreceptor retinoid-binding protein (IRBP) is an extracellular protein that has been suggested to participate in the visual process as a carrier for visual retinoids. A chimeric gene composed of the human IRBP promoter fused to the bacterial reporter gene chloramphenicol acetyltransferase (C...Restriction Mapping; Nucleic Acid Hybridization; Mice; Gene Expression1990-05-25
22 Olson, Randall J.Early experiences with microphacoMicrophaco is the separation of irrigation from aspiration that allows removal of cataracts through sub-2mm incisions. While proven intraocular lenses (IOLs) are not available at this time to take advantage of the small wounds, these wounds are advantageous from a separating irrigation standpoint w...Microphaco; Cataracts; Irrigation; Wounds2004
23 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
24 Olson, Randall J.; Mamalis, Nick; Spencer, Terrence S.Postoperative sterile endophthalmitis (TASS) associated with the memorylensPURPOSE: To report 10 cases of delayed-onset acute intraocular inflammation following cataract extraction and posterior chamber implantation of the MemoryLens(R) intraocular lens (IOL). SETTING: John A. Moran Eye Center, Department of Ophthalmology, University of Utah, Salt Lake City, Utah, USA. MET...Memory Lens; Toxic Anterior Segment Syndrome; Retrospective Studies; adverse effects2000-12
25 Digre, Kathleen B.; Gouw, Launce G.; Harris, Catherine P.; Haines, John H.; Ptacek, L.J.Autosomal dominant cerebellar ataxia with retinal degeneration: clinical, neuropathologic, and genetic analysis of a large kindred.The autosomal dominant cerebellar ataxias (ADCA) comprise a heterogeneous group of neurologic disorders characterized by degeneration of the cerebellum, spinal cord, and brainstem. Genetic analysis has revealed two loci, SCA1 on chromosome 6p, and SCA2 on chromosome 12q, responsible for some ADCA. W...Retinal Degeneration; Cerebellar Ataxia; Genetic Analysis1994-08
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