The Psychodynamic theory emphasizes the concept of unresolved conflict. In the case of Selective Mutism, this theory supposes that the individual has 
1) an oral and/or anal fixation and may be maintaining a family secret or some kind of family-related discomfort (such as abuse, divorce, death, a life threatening experiences, frequent house moving), and/or
2) have displaced anger towards a family member (such as a parent), or is involved in a family relationship characterized by dependence, ambivalence, and an excessive need to control -- the neurotic relationship between the parent and the child with SM may carry over to the child's interactions with others, and/or
3) is regressing to a nonverbal stage in their development. 

The Selective Mutism is hence viewed as a coping mechanism to deal with that anger and anxiety from this repression, representing the behavior as a way to punish the individual's parents and other family members. 

This theory has very little empirical data to support this model, and hence is a theory that is currently losing validity. 

Psychodynamic Theory of Selective Mutism

In this theory, Selective Mutism is portrayed as an unconscious, language-based form of behavioral inhibition or as a defense mechanism. This perspective is significant because it frames selective mutism as a symptom of anxiety, rather than consciously manipulative behavior. (Reference: Wong)

Behavioral Theory of Selective Mutism 

This theory of Selective Mutism, proposed by Black and Uhde, views the phenomenon of Selective Mutism through the lens of social phobia. 

Their proposed theory is as follows: Selective Mutism is a variant of social phobia, characterized by excessive social anxiety; under this model, Selective Mutism is seen as the severe end of the spectrum for childhood speech inhibition and social anxiety.  

Black & Uhde's argument is based upon their collected data which shows higher instances of Selective Mutism in families with a family history of Social Anxiety. 

(To learn more about Black & Uhde's theory, or to view the study containing their data, please move to the relation node titled 'Black & Uhde's Evidence Supporting Social Theory & Social Anxiety of Selective Mutism')

(While some researchers support this theory, there has been another study which challenges the notion that Selective Mutism is a variant and can be explained by social anxiety and social phobia. To learn more about this, please move to the relation node titled 'Evidence Challenging Black & Uhde's Social Theory & Social Anxiety of Selective Mutism') 

Social Theory and Social Anxiety Theory of Selective Mutism

There are many theories which attempt to explain the etiology of Selective Mutism. This concept node and its child relation nodes will explore theories for SM through these following lens/frameworks: 

1) Psychodynamic Theory
2) Behavioral Theory 
3) Social phobia and Social Anxiety 
4) Family Systems Theory 
5) Dissociative Identity Theory 
6) Post-traumatic Stress Theory
7) Developmental Psychopathology Theory 

A table from 'Wong, Priscilla. "Selective Mutism: A Review and Integration of Etiology, Comorbities, and Treatment." paper has provided a table that may be helpful (see image; cred: Wong, Theories on the Etiology of Selective Mutism). 

New York University

Limited speech can be a sign of selective mutism, an anxiety disorder characterized by lack of speech across settings. Selective mutism may develop among children with speech sound disorder due to embarrassment about their errors or impairment, but many children with selective mutism exhibit normal speech in settings they deem "safe."

Selective Mutism as a Differential Diagnosis to Speech Sound Disorder

Wong, Priscilla. “Selective Mutism: A Review of Etiology, Comorbidities, and Treatment.” Psychiatry (Edgmont (Pa. : Township)), vol. 7, no. 3, Mar. 2010, pp. 23–31, www.ncbi.nlm.nih.gov/pmc/articles/PMC2861522/. Accessed 2 June 2023.

The "Definition and Diagnostic Criteria of Selective Mutism" relation node included paraphrase information regarding the criteria and definition of Selective Mutism. 

Wong, Priscilla. “Selective Mutism: A Review of Etiology, Comorbidities, and Treatment.” 

Theories on the Etiology and Emergence of Selective Mutism 

Definition: Selective Mutism (SM) is an anxiety disorder which often appears in early childhood, characterized by the PERSISTENT failure to engage in speech in specific social situations where speech is typically expected, despite technically possessing the full capability (the necessary physical structures and speech motor processes) to being able to speak and hear. 

Selective Mutism often co-exists with Social Anxiety Disorder (SAD). 

The DSM-IV-TR criteria for Selective Mutism specifies that this persistent failure to speak should not be attributed to these following reasons: 

1) An organic inability rooted in the individual's language capability (e.g. comprehension, in-fluency in language, etc) 
2) Another communication disorder (e.g. stuttering) 
3) A diagnosis of another psychotic disorder (e.g. Pervasive Development Disorder, Schizophrenia, etc) 

Please note that a comprehensive and uniform theory about the etiology, assessment, and treatment of SM does not exist; Historically, varying definitions and criteria have been applied to individuals with SM, and so this provided definition and diagnostic criteria may not be yet as inclusive as it can be. 

Image citation: Journal of American Academy of Psychology. Factors That May Influence Speech and Social Inhibition., 17 Feb. 1995, www.sciencedirect.com/science/article/abs/pii/S0890856709635930. Accessed 22 June 2023.

Definition and Diagnostic Criteria of Selective Mutism 

Prevalence estimates for SM range between 0.2% - 1.6%. SM Prevalence may be higher in immigrant children, individuals in a language-minority group, or individuals with speech/language delays. SM often occurs between ages 3-6, while diagnosis for this disorder often occurs during ages 5-8 -- about the time children enter school. 

Note that there is currently a lack of consensus regarding the population estimates of SM, as they are difficult to ascertain; this data has been gathered via various different diagnostic criteria and population samples which have been compared to one another. Additionally, there is no consensus on the relation between SM prevalence and gender assigned at birth. While most studies report that it affects females more than males, some studies find that it affects more males than females, or that there seems to be no difference by gender.  

Definitions: 

The INCIDENCE of Selective Mutism refers to the number of new cases identified in a specific time period. 

The PREVALENCE of Selective Mutism refers to the number of individuals who are living with Selective Mutism in a current time period. 

Incidence and Prevalence of Selective Mutism

Treatment for Selective Mutism for a long time has been considered difficult. Some approaches used for treating Selective Mutism include 

1) Behavioral Interventions, 
2) Psych-dynamic Therapy, 
3) Family Therapy, 
4) Speech Therapy,
5) Pharmacological Intervention (this is a relatively new approach). 

Please note that the majority of reports of Selective Mutism treatment is based off of case-studies. 

While case-studies can be beneficial to describe new approaches or interventions, generalizing from case-studies may problematic as they are often unable to be replicated (due to insufficiently described methodology, or it being an incredibly specific situation), having unstandardized outcomes measures, alternative symptoms not explored, or including cherry-picked data (where unsuccessful cases are unreported).  

Treatment & Management Methods for Selective Mutism

Here are all the citation references for the Selective Mutism nodes. 

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