In order to understand how sounds are made, experimental procedures are often adopted. For example, we can measure how the tongue makes contact with the roof of the mouth in normal speech production by using a technique called electropalatography (or EPG). In order to collect EPG data, the speaker needs to be fitted with a special prosthetic palate, which contains a number of electrodes. The way in which the electrodes are "contacted" by the tongue during speech provides us with important information, such as how much of the palate is contacted in different speech sounds, or which regions of the palate are contacted, or what the duration of the contact is.
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