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Visual Prosthesis Part Two

Submitted by lianarh on Sun, 10/22/2017 - 16:02

Glasses, contacts, and intraocular lenses can correct a variety of issues, as discussed in Visual Prosthesis Part One. There are other areas in the visual pathway where damage can result in visual impairment. More advanced technologies may be required to help correct them. Some examples of these technologies include retinal implants, BrianPort, and vOICe.

Visual Prosthesis Part One

Submitted by lianarh on Sat, 10/21/2017 - 11:21

Damage can arise from a variety of issues in the visual pathway, affecting structures from the eyes to the visual cortex of the brain. The resulting impairments can change the way a person navigates the world. There are long standing systems in place as alternatives for those who are visually impaired, such as glasses, braille, and walking sticks.

Red Light Green Light... Or is that Black Light Yellow Light? Color Blindness: Types and Testing

Submitted by pazm1 on Fri, 09/29/2017 - 19:50

Most humans all see relatively the same colors. Our eyes see colors because it contains three cell types called cones. They are named red, blue and green cones because the wavelength of light that they see the best. The graph below shows the wavelengths that the cones can see. We are able to differentiate more colors because when we have equal amounts of signals coming from green and red cones than we see the color yellow. When we only have the red cones sending signals than we see the color red.

A Scary Eye Monster that Lurks in the River

Submitted by Anonymous (not verified) on Fri, 04/28/2017 - 06:44

     Onchocerca volvulus is a parasitic worm that can damage the eyes and skin of its host. This parasite is transmitted to humans by blackfly bites of the simulium species. The flies are found near fast-running streams and rivers in the inter-tropical zones. Infection by this parasite is most common in Africa, however, it is also seen in Latin America and Yemen. This parasite greatly increases the risk of blindness in individuals living near rivers where the flies quickly breed.