Muscle Memory

When one picks up a hair brush, one automatically has a certain motion, style, number of strokes, and amount of pressure as the hair is brushed without requiring conscious thought about each movement. Other forms of rather elaborate motions that have become automatic include speech. As one speaks, one usually does not consciously think about the complex tongue movements, synchronisation with vocal cords and various lip movements that are required to produce phonemes, because of muscle memory. In speaking a language that is not one's native language, one typically speaks with an accent, because one's muscle memory is tuned to forming the phonemes of one's native language, rather than those of the language one is speaking. An accent can be eliminated only by carefully retraining the muscle memory. From Wikipedia.

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