Selective Mutism: Identification of Subtypes and Implications for Treatment

Selective Mutism (SM) is a rare disorder in which afflicted children will speak normally in one setting (usually home) and will not speak in other environments, such as school. The occurrence in the general population is so low that school psychologists, physicians, and other treating professionals may know little about the disorder or ever have the opportunity to work with children withSM. The criteria and essential feature of SM according to the Diagnostic and Statistical Manual of Mental Disorders-Fifth Edition (DSM5) (American Psychiatric Association, 2013) is the child’s persistent failure to speak in specific social situations where speaking is expected, and at the same time, the child does speak in other situations; therefore, their problem is “selective” and inconsistent across environments, which makes diagnosis challenging. Instead of communicating by standard verbal expression in these selectively mute situations, children with this disorder may communicate by gestures, nodding, or head shaking, or pulling or pushing, or, in some cases, by short monosyllabic or monotone utterances, or in an altered voice. As a result, SM often interferes with educational or occupational achievement and/or with social communication or adjustment. The DSM-5stipulates it must last for at least one month, but not limited to the first month of school. SM should not be diagnosed if the child’s failure to speak is due solely to a lack of knowledge, or discomfort with the spoken language required in a social situation (APA, 2013). It is also not diagnosed if the disturbance is better accounted for by embarrassment related to having a language or Communication Disorder, or if it occurs exclusively in the presence of a Pervasive Developmental Disorder, Schizophrenia or other Psychotic Disorder (APA, 2013).