Selective Mutism

Selective mutism affects 0.5 to 1 percent of children, typically presenting at age 3 to 6 with onset of preschool or kindergarten. The child speaks normally at home with family but remains silent in school, public, or with extended family for at least one month, beyond the first month of school adjustment. The pattern significantly interferes with educational achievement and social communication.

Comorbid conditions are nearly universal: 90 percent meet criteria for social anxiety disorder, with separation anxiety, specific phobias, oppositional behaviors, and language delays also common. Family history of anxiety disorders is frequent. Bilingual children and immigrants have higher prevalence, possibly reflecting language anxiety amplifying underlying social anxiety.

Treatment combines behavioral therapy (graduated exposure, stimulus fading, contingency management, social skills training), parent and teacher education, and selective serotonin reuptake inhibitors (fluoxetine) for moderate to severe cases or when behavioral therapy plateaus. Early intervention prevents chronic course; with treatment, 50 to 75 percent achieve verbal communication in school within one year. Untreated SM may persist into adolescence with increased depression risk.