Hi.. I want a seminar report on electrooculography topic in powerpoint document.. So please send me the seminar report to my email.. My email id is (arunyuvan46[at]gmail.com).. I will wait for ur reply.. Thank you..
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seminar report on electrooculography
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Hi.. I want a seminar report on electrooculography topic in powerpoint document.. So please send me the seminar report to my email.. My email id is (arunyuvan46[at]gmail.com).. I will wait for ur reply.. Thank you..
25-03-2017, 03:57 PM
Electrooculography (EOG / E.O.G.) is a technique to measure the corneal-retinal resting potential that exists between the front and the back of the human eye. The resulting signal is called the electrooculogram. The primary applications are in the diagnosis of ophthalmology and in the recording of eye movements. Unlike electroretinogram, EOG does not measure response to individual visual stimuli. To measure eye movement, electrode pairs are normally placed above and below the eye or to the left and right of the eye. If the eye moves from the central position towards one of the two electrodes, this electrode "sees" the positive side of the retina and the opposite electrode "sees" the negative side of the retina. As a result, a potential difference between the electrodes occurs. Assuming that the resting potential is constant, the potential recorded is a measure of the position of the eye.
EOG is used to evaluate the function of the pigment epithelium. During darkness adaptation, the resting potential decreases slightly and reaches a minimum ("dark") after several minutes. When the light is turned on, there is a substantial increase in the resting potential ("peak light"), which disappears after a few minutes when the retina adapts to light. The ratio of voltages (ie, the peak of light divided by the dark channel) is known as the Arden ratio. In practice, the measurement is similar to ocular motion recordings (see above). The patient is asked to change the position of the eyes repeatedly between two points (alternating looking from the center to the left and from the center to the right). Since these positions are constant, a change in recorded potential comes from a change in the resting potential.
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