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1 Horch, Kenneth W.; Normann, Richard A.Noble metal penetrating cortical stimulating electrode array: preliminary resultsElectrical stimulation of the visual cortex causes subjects to see spots of light (phosphenes) in their visual fields. We have developed arrays of penetrating electrodes which may from the basis of a visual prosthesis centered around electrical stimulation of the visual cortex. These arrays have bee...Visual prosthesis1988
2 Horch, Kenneth W.; Normann, Richard A.Simulation of a phosphene field based visual prosthesisA visual prosthesis for the blind based upon electrical stimulation of the visual cortex requires the development of an array of electrodes. To establish design specifications for such an electrode array, we have conducted psychophysical experiments with normally sighted subjects wearing a portable...Visual prosthesis; Phosphene simulator1990
3 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
4 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
5 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
6 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
7 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
8 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
9 Sample, SusanMore than meets the eyeIf you depend only upon your eyes, you won't see what's really going on in a research lab-even in the Department of Ophthalmology and Visual Sciences, where the focus is on understanding vision. "You don't really see with the eye," said Jennifer S. Lund, Ph.D., professor of ophthalmology at the Un...Vision; Molecular Biology; Eye2001-09
10 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
11 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
12 Gerig, GuidoFunctional connectivity MR imaging reveals cortical functional connectivity in the developing brainBACKGROUND AND PURPOSE: Unlike conventional functional MR imaging where external sensory/cognitive paradigms are needed to specifically activate different regions of the brain, resting functional connectivity MR imaging acquires images in the absence of cognitive demands (a resting condition) and de...2008-01-01
13 Mathews, V. JohnA new model of perceptual threshold functions for application in image compression systemsThis paper discusses the development of a perceptual threshold model for the human visual system. The perceptual threshold functions describe the levels of distortions present at each location in an image that human observers can not detect. Models of perceptual threshold functions are useful in ima...1995
14 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
15 Research in brief: Summer 2004Summaries of Selected Research Projects at the University of Utah Health Sciences CenterResearch: School of Medicine, College of Pharmacy;, College of Nursing, College of Health2004-06
16 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
17 Friedrich, FrancesVisual perception without awareness in a patient with posterior cortical atrophy: impaired explicit but not implicit processing of global informationA patient with progressive posterior cortical atrophy (PCA) was examined on several tests of visual cognition. The patient displayed multiple visual cognitive deficits, which included problems identifying degraded stimuli, attending to two or more stimuli simultaneously, recognizing faces, tracing s...Posterior cortical atrophy; Global-local processing; Consciousness; Balint's syndrome; Simultanagnoisa2002
18 Friedrich, FrancesVisual perception without awareness in a patient with progressive posterior cortical atrophy: impaired explicity but not implicit processing or global informationA patient with progressive posterior cortical atrophy (PCA) was examined on several tests of visual cognition. The patient displayed multiple visual cognitive deficits, which included problems identifying degraded stimuli, attending to two or more stimuli simultaneously, recognizing faces, tracing...Posterior cortical atrophy; Global-local processing; Consciousness; Balint's syndrome; Simultanagnosia2002
19 Tasdizen, TolgImage processing, pattern recognition and connectomics2011-10-25
20 Foster, Norman L.Novel insertional presenilin 1 mutation causing Alzheimer disease with spastic paraparesis.A four-generation pedigree exhibiting early-onset autosomal dominant Alzheimer disease (AD) with spastic paraplegia, dystonia, and dysarthria due to a novel 6-nucleotide insertional mutation in exon 3 of the presenilin 1 gene (PS1) is described. Serial examinations, PET scans, and autopsy revealed t...Older people, 80 and over; Membrane Proteins; Neuropsychological Tests2004-05-25
21 Creem-Regehr, Sarah Hope; Gooch, Amy A.; Sahm, Cynthia S.; Thompson, William B.Perceiving virtual geographic slant: action influences perceptionFour experiments varied the extent and nature of observer movement in a virtual environment to examine the influence of action on estimates of geographical slant. Previous slant studies demonstrated that people consciously overestimate hill slant but can still accurately guide an action toward th...Geographical slant; Virtual environment2003-06-16
22 Couldwell, William T.Photophobia in a blind patient: an alternate visual pathwayPhotophobia 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 mult...2006-11
23 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
24 Baxter, Brent S.Image processing in the human visual systemThis work extends the multiplicative visual model to include image texture as suggested by experiments [Campbell, Weisel] linking a low resolution Fourier analysis with neurons in certain parts of the visual cortex. The new model takes image texture into account in the sense that weak texture is acc...Human visual system; Image texture1975
25 Fletcher, Thomas H.Analysis of human brain connectivity from multi-modal imaging2012
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