Читать книгу Human Communication Technology - Группа авторов - Страница 36

For non-invasive method the terminals are put an external portion of the cerebrum; consequently, nope medical procedure is obligatory. This sort of strategy needs nature of Electroencephalography signals. As the account of the sign is removed a long way from the basis, thus indications get contorted. Also, the quality of acquired signals is minor sufficiency that for obtrusive case [14]. A procurement framework can be isolated dependent on cathodes categories such as surface, needle, or other electrodes [15]. Short out commotion level is low if there should be an occurrence of the water-based framework. The most elevated P300 spelling exactness’ are acquired in the hydrogel-based framework. The minimum burden is accessible through needle terminal-based framework. There are different electrode materials available to measure and record the electroencephalography signal from the brain of the human body. They are listed as follows:

 • Surface Electrodes made of AgCl

 • Surface Electrodes made of Stainless steel

 • Surface Electrodes made of Molybdenum

 • Dry Electrodes.

These electrodes are placed over the brain of a human being for testing and recording the electroencephalography signal. The main advantage of this type of surface electrodes (Non-Invasive) is it does not cause any pain during tests. Moreover, the surface electrode made of Silver Chloride is widely used because of its temperature co-efficient and efficient Signal to noise ratio compared to other materials of surface electrodes.