Elective mutism
Complete lack of speech (mutism) that is believed to be volitional (willed) on the part of the patient. True elective mutism may be a reaction to a traumatic event, the aftermath of an injury to the mouth or throat, particularly if it is painful, or a symptom of extreme shyness. In some cases, the lack of speech is eventually found not to be volitional, but a sign of damage or deformity of the speech apparatus, or a feature of infantile autism. See also selective mutism.
* * *
selective m.
Medical dictionary.
2011.