Selective mutism (SM) refers to the child’s and/or adolescents’ persistent inability to speak in certain social situations, even though they are perfectly able to speak and understand language. SM has been linked to an extreme form of social anxiety, and thus it is proposed that anxiety could be a contributing factor in the etiology (i.e., cause of an illness) of the condition.
MUTISM VS SELECTIVE MUTISM
Mutism, by contrast, typically occurs following a traumatic experience or brain damage; it is a pervasive and predominant symptom in the life of the individual, which means that is present all the time, not only in specific circumstances. Unlike cases of mutism, studies on SM generally did not find histories of trauma among the children.
SELECTIVE MUTISM AND ANXIETY
Recent studies focusing on the relationship between anxiety and SM highlight the effectiveness of anti-anxiety medication in the treatment of SM, implicating the role of anxiety in the condition. The current study comparing SM and SP (social phobia) in children supports the hypothesis that anxiety contributes to the etiology of SM. Specifically, the authors reason that SM could be a coping mechanism for social anxiety, which works by using silence to avoid the risk of humiliation.
It is noteworthy to add that the study also provides preliminary support for the presence of subtle language deficits in SM, as SM children were found to underperform in language tasks compared to SP children. For example SM is often seen in children for whom English is not their native language, thus implicating both anxiety and language impairment. It is however unclear whether anxiety or language impairment comes first, or whether or not they co-occur at the same time.
Reference:
Manassis K, Fung D, Tannock R, Sloman L, Fiksenbaum L, McInnes A. Characterizing selective mutism: is it more than social anxiety?. Depress Anxiety. 2003;18(3):153-161. doi:10.1002/da.10125