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Articulography
PHONETICS: Electromagnetic midsagittal articulography is a transmitter system in which very small receivers, placed at various points (e.g. lips, teeth, parts of the tongue), send movement signals whch are accurately plotted as articulatory trajectories, using a system of absolute coordinates.This technique can be used to show that vertical tongue body movements during the articulation of a consonant are affected by such factors as voicing and the nature of adjacent vowels.