Definition reprinted with permission from Hood, Stephen B. (editor) available from Stuttering Foundation of America: Stuttering Words (Publication No 2: Speech Foundation of America)
Inconsistent loss or impairment of the ability to execute a complex sequence of coordinated movements, as in the articulation of speech: the inconsistent ability to remember how to produce a complex motor sequence of events, especially on multisyllabic words, multisyllable phrases and "tongue twisters." Caused by damage to the central nervous system.
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