Selective Mutism
Selective Mutism (formerly known as elective mutism) is a condition where an individual doesn't speak in some situations but speaks at other times. This is most common in children starting before 5 years of age. It is exhibited by a failure to speak in specific situations (such as when in school) but the lack of speech is not due to a speech/hearing disorder or lack of knowledge about the language. The individual will be able to speak in other situations (when at home). This condition often occurs along with an anxiety disorder, extreme shyness, and social withdrawal.