First, one fundamental circuit process in the visual system transforms the intensity of a light signal into an estimate of contrast, the change in light level relative to a previous intensity. This proposal focuses on three computations that are central to vision. This proposal develops the Drosophila visual system as a model in which the functions of these microcircuits can be dissected at the molecular, cellular and behavioral level, and combines techniques drawn from genetics and systems neuroscience to derive new understanding. These neural processes can be broken down into the individual actions of relatively simple microcircuits, small groups of neurons that perform elementary operations that are widespread in the brain, but which subserve distinct purposes in different contexts. To connect perception to action in this context, complex visual scenes must be efficiently represented in the neural activities of relatively small groups of cells from these signals, particularly salient cues are extracted, integrated with behavioral goals, and linked to the appropriate responses. Clandinin Vision provides critical sensory inputs that guide our routine behaviors as a result, blindness represents perhaps the most devastating deprivation we can experience. Micro Acupuncture treatment has been helping many RP patients to increase their vision fields, prevent or slow their vision loss or at least halt the progression of the disease.R01 EY022638 Dissecting neural circuit computations in the peripheral visual system PI: Thomas R. It’s one of the most common causes of blindness in children. And another one is Leber Congenital Amaurosis, a rare inherited eye disease, a severe dystrophy of the retina that appears at birth or in the first few months of life. The most common one is Usher Syndrome, where hearing and vision are both affected. Other inherited diseases also share some of the clinical symptoms of RP. This degeneration is progressive and has no known cure. It affects about 100,000 people in North America. The main risk factor is family history of RP. Also Loss of centralvision (in advanced cases).Loss of peripheral vision, causing “tunnel vision”(in moderate or severe cases).Decreased vision at night or in low light (in mild cases).Slow adjustment from dark to light environments and vice versa.Most people with RP experience loss of their peripheral vision but maintain their central vision until late in the disease. The rate of progression and degree of visual loss varies from person to person. It is usually discovered when the patient complains about not being able to see at night. RP is typically diagnosed in adolescents and young adults. When the more centrally located cones – responsible for color and sharp central vision – become involved, the loss is in color perception and central vision. In some patients, RPis mild while in others, it can lead to blindness. At early stage, patients notice difficulty seeing in low light or at night and lose peripheral vision over time.
Because rods are concentrated in the outer portions of the retina and are triggered by dim light, their degeneration affects peripheral and night vision. With RP, the rods cells that are responsible for peripheral and night vision are damaged by genetic mutations and deteriorate.Rods are usually affected first. The photoreceptor or light cells called Rods and Cones within the retina capture and convert images to nerve signals and send them to the brain through optic nerve. The retina is the layer of tissue at the back of the inner eye. Retinitis Pigmentosa is one of the most common forms of inherited retinal degeneration. Retinitis Pigmentosa at Different Stages from mild to moderate to severe
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