Selective mutism is a persistent and debilitating condition in which a child fails to speak in public situations where speaking is expected. Children with selective mutism often speak well in familiar situations such as home but do not speak to people in public situations such as parks, shopping malls, restaurants, and school. Failure to speak must last at least one month. Selective mutism does not generally apply to youths with a communication disorder such as stuttering or to youths who lack comfort or knowledge with the primary language spoken in public situations, though many children with selective mutism do have some aspect of a communication disorder.
Selective mutism affects about 2% of children, with girls slightly more affected than boys. The disorder commonly begins during preschool years but treatment is often delayed by parents or others who believe the problem is temporary. Selective mutism may have a chronic course for some children and can produce significant problems with respect to peer rejection, incomplete verbal academic tasks or standardized tests, or inadequate language or social skills.
Many researchers have linked selective mutism to social anxiety disorder or an extreme form of social anxiety. Others have found children with selective mutism to display characteristics of oppositionality, developmental disorder, depression, and trauma-based reactions. A recent study indicated that children with selective mutism are often present in one of three main groups: anxious-mildly oppositional, anxious-communication delayed, and exclusively anxious. A primary goal of treatment for selective mutism is to increase the audibility and frequency of speech, especially in public situations such as school.
A resource for parents of children with excessive shyness or selective mutism is:
Kearney, C.A. (2011). Silence is not golden: Strategies for helping the shy child. New York: Oxford University Press.
A resource for school officials who address children with selective mutism is:
Kearney, C.A. (2010). Helping youths with selective mutism and their parents: A guide for school-based professionals. New York: Oxford University Press.