Reduced auditory processing capacity during vocalization in children with Selective Mutism

[Measurement of speech in individuals with selective mutism: A systematic review]

Background: The main characteristic of selective mutism (SM) is the failure to speak in specific social situations. Thus, assessing speech across social contexts is important for confirming a diagnosis of SM and for differentiating it from other disorders. The purpose of this review was to organize how the core symptom of SM, a lack of speech in specific social situations, has been assessed in previous studies. Methods: A systematic search of articles was conducted in three databases, Web of Science, PsycINFO, and PubMed and reviews of surveys or experimental studies that reported empirical data on individuals with SM were performed. We excluded review, qualitative, epidemiological, and intervention studies. The study summarized the diagnostic criteria, methods of confirming SM diagnosis, distinction of SM from other disorders, and methods of speech assessment. Results: A total of 447 articles were screened, where 60 articles were considered eligible. The results demonstrate that different interviews and questionnaires were used to establish the diagnosis of SM. However, the majority of interviews and questionnaires lacked validation. Only two (2/60) articles used validated methods of speech assessment to confirm SM diagnosis. Moreover, a consensus was lacking on the assessment method for differentiating SM from other disorders across studies. Specifically, 17 studies measured speech and are not intended for diagnosis. The majority of studies (16/17) used the questionnaire to assess the severity of the SM condition, and only one study conducted behavioral observation. Assessment methods based on the measurement of speech in real-life situations for individuals with SM were not established. Conclusion: We have the limitation that we did not review intervention studies. However, this systematic review revealed the problem that speech assessment methods for surveys or experimental studies of SM were not established. Future studies should establish methods of speech assessment across social situations to assess SM symptoms.

[Measurement of speech in individuals with selective mutism: A systematic review]

Background: The main characteristic of selective mutism (SM) is the failure to speak in specific social situations. Thus, assessing speech across social contexts is important for confirming a diagnosis of SM and for differentiating it from other disorders. The purpose of this review was to organize how the core symptom of SM, a lack of speech in specific social situations, has been assessed in previous studies. Methods: A systematic search of articles was conducted in three databases, Web of Science, PsycINFO, and PubMed and reviews of surveys or experimental studies that reported empirical data on individuals with SM were performed. We excluded review, qualitative, epidemiological, and intervention studies. The study summarized the diagnostic criteria, methods of confirming SM diagnosis, distinction of SM from other disorders, and methods of speech assessment. Results: A total of 447 articles were screened, where 60 articles were considered eligible. The results demonstrate that different interviews and questionnaires were used to establish the diagnosis of SM. However, the majority of interviews and questionnaires lacked validation. Only two (2/60) articles used validated methods of speech assessment to confirm SM diagnosis. Moreover, a consensus was lacking on the assessment method for differentiating SM from other disorders across studies. Specifically, 17 studies measured speech and are not intended for diagnosis. The majority of studies (16/17) used the questionnaire to assess the severity of the SM condition, and only one study conducted behavioral observation. Assessment methods based on the measurement of speech in real-life situations for individuals with SM were not established. Conclusion: We have the limitation that we did not review intervention studies. However, this systematic review revealed the problem that speech assessment methods for surveys or experimental studies of SM were not established. Future studies should establish methods of speech assessment across social situations to assess SM symptoms.

[Measurement of speech in individuals with selective mutism: A systematic review]

Background: The main characteristic of selective mutism (SM) is the failure to speak in specific social situations. Thus, assessing speech across social contexts is important for confirming a diagnosis of SM and for differentiating it from other disorders. The purpose of this review was to organize how the core symptom of SM, a lack of speech in specific social situations, has been assessed in previous studies. Methods: A systematic search of articles was conducted in three databases, Web of Science, PsycINFO, and PubMed and reviews of surveys or experimental studies that reported empirical data on individuals with SM were performed. We excluded review, qualitative, epidemiological, and intervention studies. The study summarized the diagnostic criteria, methods of confirming SM diagnosis, distinction of SM from other disorders, and methods of speech assessment. Results: A total of 447 articles were screened, where 60 articles were considered eligible. The results demonstrate that different interviews and questionnaires were used to establish the diagnosis of SM. However, the majority of interviews and questionnaires lacked validation. Only two (2/60) articles used validated methods of speech assessment to confirm SM diagnosis. Moreover, a consensus was lacking on the assessment method for differentiating SM from other disorders across studies. Specifically, 17 studies measured speech and are not intended for diagnosis. The majority of studies (16/17) used the questionnaire to assess the severity of the SM condition, and only one study conducted behavioral observation. Assessment methods based on the measurement of speech in real-life situations for individuals with SM were not established. Conclusion: We have the limitation that we did not review intervention studies. However, this systematic review revealed the problem that speech assessment methods for surveys or experimental studies of SM were not established. Future studies should establish methods of speech assessment across social situations to assess SM symptoms.

[Measurement of speech in individuals with selective mutism: A systematic review]

Background: The main characteristic of selective mutism (SM) is the failure to speak in specific social situations. Thus, assessing speech across social contexts is important for confirming a diagnosis of SM and for differentiating it from other disorders. The purpose of this review was to organize how the core symptom of SM, a lack of speech in specific social situations, has been assessed in previous studies. Methods: A systematic search of articles was conducted in three databases, Web of Science, PsycINFO, and PubMed and reviews of surveys or experimental studies that reported empirical data on individuals with SM were performed. We excluded review, qualitative, epidemiological, and intervention studies. The study summarized the diagnostic criteria, methods of confirming SM diagnosis, distinction of SM from other disorders, and methods of speech assessment. Results: A total of 447 articles were screened, where 60 articles were considered eligible. The results demonstrate that different interviews and questionnaires were used to establish the diagnosis of SM. However, the majority of interviews and questionnaires lacked validation. Only two (2/60) articles used validated methods of speech assessment to confirm SM diagnosis. Moreover, a consensus was lacking on the assessment method for differentiating SM from other disorders across studies. Specifically, 17 studies measured speech and are not intended for diagnosis. The majority of studies (16/17) used the questionnaire to assess the severity of the SM condition, and only one study conducted behavioral observation. Assessment methods based on the measurement of speech in real-life situations for individuals with SM were not established. Conclusion: We have the limitation that we did not review intervention studies. However, this systematic review revealed the problem that speech assessment methods for surveys or experimental studies of SM were not established. Future studies should establish methods of speech assessment across social situations to assess SM symptoms.

Characteristics of person, place, and activity that trigger failure to speak in children with selective mutism

Selective Mutism (SM) is an anxiety disorder with predictable and circumscribed situations in which children remain silent while they speak unaffectedly in others. However, core features of anxiety inducing stimuli have rarely been studied so far. Parents of children with elevated SM symptomatology participated in an online-based study and answered open ended questions about specific characteristics of a person, place, and activity that elicit failure to speak in their child. The final sample consisted of n = 91 parents with children aged between 3 and 17 years (M = 8.02 years, SD = 3.94). Answers were analyzed by qualitative content analysis. Characteristics of a person were assigned to five categories with lack of distance as the most frequently reported feature. With respect to a place, the majority of parents mentioned unknown places as a silence trigger. The most frequently mentioned feature of an activity that was designated to be associated to silence was new activity. There were only few associations between the designation of these features, age, and gender. For the first time, anxiety inducing triggers related to person, place, and activity were comprehensively assessed in children with SM. This allows a differentiated and deeper understanding of an understudied disorder. The majority of characteristics can be associated with proposed etiological factors such as increased behavioral inhibition, conditioning processes, social anxiety, and a strong need for control. Implications for effective treatments are discussed.

Betrayed by the nervous system: a comparison group study to investigate the 'unsafe world' model of selective mutism

The study presented in the following verifies some assumptions of the novel 'unsafe world' model of selective mutism (SM). According to this model, SM is a stress reaction to situations erroneously experienced via cognition without awareness as 'unsafe'. It assumes a high sensitivity to unsafety, whereby the nervous system triggers dissociation or freeze mode at relatively low thresholds. We examine whether there is a correlation between SM, sensory-processing sensitivity and dissociation. We compared a sample of 28 children and adolescents with SM (mean age 12.66 years; 18 females) to 33 controls without SM (mean age 12.45 years; 21 females). Both groups were compared using a medical history sheet, the 'Selective Mutism Questionnaire' (SMQ), a 'Checklist for Speaking Behaviour' (CheckS), the 'Highly Sensitive Person Scale' (HSPS), the 'Child Dissociative Checklist' (CDC), the 'Adolescent Dissociative Experience Scale' (A-DES) and the 'Social Phobia and Anxiety Inventory for Children' (SPAIK). Appropriate parametric and non-parametric tests were conducted to examine differences between groups. The results indicate that sensory-processing sensitivity was significantly higher in the group of children and adolescents with SM [X2(1) = 7.224, p = 0.0007; d = 1.092]. Furthermore, dissociative symptoms were more common in children and adolescents with SM than in controls [F(1, 33) = 13.004, p = 0.001; d = 0.986]. The results indicate that sensory-processing sensitivity and dissociation are important factors of SM that may hold important implications for the treatment. TRIAL REGISTRATION: This study is registered with the ClinicalTrials.gov number NCT04233905.

Anxiety in Children with Selective Mutism: A Meta-analysis

This study evaluates the current conceptualization of selective mutism (SM) as an anxiety disorder in the DSM-5 using a meta-analytic approach. In the absence of any systematic assessment of anxiety in the field of SM, we pooled prevalence data of comorbid anxiety disorders in a random-effects meta-analysis. On the basis of 22 eligible studies (N = 837), we found that 80% of the children with SM were diagnosed with an additional anxiety disorder, notably social phobia (69%). However, considerable heterogeneity was present, which remained unexplained by a priori specified moderators. The finding that SM is often diagnosed in combination with anxiety disorders, indicates that these disorders are not discrete, separable categories. Moreover, this finding does not help to elucidate the relation between SM and anxiety as an etiological mechanism or symptomatic feature. Broadening our research strategies regarding the assessment of anxiety is paramount to clarify the role of anxiety in SM, and allow for proper classification.

Children Who are Anxious in Silence: A Review on Selective Mutism, the New Anxiety Disorder in DSM-5

Selective mutism (SM) is a relatively rare childhood disorder characterized by a consistent failure to speak in specific settings (e.g., school, social situations) despite speaking normally in other settings (e.g., at home). The latest edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5) lists SM among the anxiety disorders. This makes sense as the current review of the literature confirms that anxiety is a prominent symptom in many children suffering from this condition. Further, research on the etiology and treatment of SM also corroborates the conceptualization of SM as an anxiety disorder. At the same time, critical points can be raised regarding the classification of SM as an anxiety disorder. We explore a number of such issues in this review. Recommendations for dealing with this diagnostic conundrum are made for psychologists, psychiatrists, and other mental health workers who face children with SM in clinical practice, and directions for future research are highlighted.

The 7q11.23 Microduplication Syndrome: A Clinical Report with Review of Literature

We report a 14-year-old adolescent girl with selective mutism (SM) and a 7q11.23 microduplication detected by chromosomal microarray (CMA) analysis and reviewed the literature from 18 published clinical reports. Our patient had specific phobias, SM, extreme anxiety, obesity, cutis marmorata, and a round appearing face with a short neck and over folded ears. We reviewed the published clinical, cognitive, behavioral, and cytogenetic findings grouped by speech and language delay, growth and development, craniofacial, clinical, and behavior and cognitive features due to the 7q11.23 microduplication. This microduplication syndrome is characterized by speech delay (91%), social anxiety (42%), attention deficit hyperactivity disorder (ADHD, 37%), autism spectrum disorder (29%), and separation anxiety (13%). Other findings include abnormal brain imaging (80%), congenital heart and vascular defects (54%), and mild intellectual disability (38%). We then compared the phenotype with Williams-Beuren syndrome (WBS) which is due to a deletion of the same chromosome region. Both syndromes have abnormal brain imaging, hypotonia, delayed motor development, joint laxity, mild intellectual disability, ADHD, autism, and poor visuospatial skills but opposite or dissimilar findings regarding speech and behavioral patterns, cardiovascular problems, and social interaction. Those with WBS are prone to have hyperverbal speech, lack of stranger anxiety, and supravalvular aortic stenosis while those with the 7q11.23 microduplication have speech delay, SM, social anxiety, and are prone to aortic dilatation.

The outcome of children with selective mutism following cognitive behavioral intervention: a follow-up study

Selective mutism (SM) is a relatively rare childhood disorder and is underdiagnosed and undertreated. The purpose of the retrospective naturalistic study was to examine the long-term outcome of children with SM who were treated with specifically designed modular cognitive behavioral therapy (MCBT). Parents of 36 children who met diagnostic criteria of SM that received MCBT treatment were invited for a follow-up evaluation. Parents were interviewed using structured scales and completed questionnaires regarding the child, including the Selective Mutism Questionnaire (SMQ). Twenty-four subjects were identified and evaluated. Their mean age ± SD of onset of SM symptoms, beginning of treatment, and age at follow-up were 3.4 ± 1.4, 6.4 ± 3.1, and 9.3 ± 3.4 years, respectively. There was robust improvement from beginning of treatment to follow-up evaluation in SM, social anxiety disorder, and specific phobia symptoms. The recovery rate from SM was 84.2 %.

CONCLUSION

SM-focused MCBT is feasible in children and possibly effective in inducing long-term reduction of SM and comorbid anxiety symptoms.

WHAT IS KNOWN

• There are limited empirical data on selective mutism (SM) treatment outcome and specifically on cognitive-behavioral therapy, with the majority of studies being uncontrolled case reports of 1 to 2 cases each. • There is also limited data on the long-term outcome of children with SM following treatment. What is New: • Modular cognitive behavioral treatment is a feasible and possibly effective treatment for SM. Intervention at a younger age is more effective comparing to an older age. • Treatment for SM also decreases the rate of psychiatric comorbidities, including separation anxiety disorder and specific phobia.

Selective Mutism: The Fraternal Twin of Childhood Social Phobia

BACKGROUND

Selective mutism (SM) is an anxiety disorder with a close link to childhood social phobia (SP). Our studies compare behavioral problem profiles in children and adolescents with SM and SP and control groups and assess the comorbidity patterns of SM and SP.

METHODS

Participants aged 3-18 years with SM (n = 95), SP (n = 74) and internalizing disorders (INT, n = 46) and a typically developing control group (CG, n = 119) were assessed with the Child Behavior Checklist (CBCL); adolescents were additionally assessed with the Youth Self-Report (YSR). Comorbidity was assessed in SM and SP participants with a diagnostic interview.

RESULTS

SP was detected in 94% of children with SM. SM participants showed different behavioral and psychiatric symptoms than SP: they were more frequently affected by lifetime separation anxiety disorder (SM: 45%, SP: 26%) and oppositional defiant disorder (SM: 22%, SP: 5%), and less by generalized anxiety disorder (SM: 6%, SP: 20%) and major depression (SM: 12%, SP: 26%). Adolescents with SM showed high rates of agoraphobia (SM 27%; SP 10%) and more social problems (YSR), and were more withdrawn (CBCL, YSR) than those with SP alone. Specific behavioral problems of SM and SP compared to INT and CG were observed.

CONCLUSION

SM and SP represent separate but closely related disorders, distinct from other INT and CG, with specific patterns of lifetime comorbidities.

An auditory-neuroscience perspective on the development of selective mutism

Selective mutism (SM) is a relatively rare psychiatric disorder of childhood characterized by consistent inability to speak in specific social situations despite the ability to speak normally in others. SM typically involves severe impairments in social and academic functioning. Common complications include school failure, social difficulties in the peer group, and aggravated intra-familial relationships. Although SM has been described in the medical and psychological literatures for many years, the potential underlying neural basis of the disorder has only recently been explored. Here we explore the potential role of specific auditory neural mechanisms in the psychopathology of SM and discuss possible implications for treatment.

Sluggish vagal brake reactivity to physical exercise challenge in children with selective mutism

Cardiovascular response patterns to laboratory-based social and physical exercise challenges were evaluated in 69 children and adolescents, 20 with selective mutism (SM), to identify possible neurophysiological mechanisms that may mediate the behavioral features of SM. Results suggest that SM is associated with a dampened response of the vagal brake to physical exercise that is manifested as reduced reactivity in heart rate and respiration. Polyvagal theory proposes that the regulation of the vagal brake is a neurophysiological component of an integrated social engagement system that includes the neural regulation of the laryngeal and pharyngeal muscles. Within this theoretical framework, sluggish vagal brake reactivity may parallel an inability to recruit efficiently the structures involved in speech. Thus, the findings suggest that dampened autonomic reactivity during mobilization behaviors may be a biomarker of SM that can be assessed independent of the social stimuli that elicit mutism.

Comorbidity and Family Factors Associated with Selective Mutism

Recent findings suggest that Selective Mutism (SM) is best conceptualized as a childhood anxiety disorder and that oppositional behavior may or may not be a significant part of the clinical picture. Twenty-nine mothers of children with SM and 28 mothers of children who did not meet diagnostic criteria for any Axis I disorder (a community comparison group) completed parental self-report questionnaires and clinician-rated interviews assessing anxiety and oppositional behavior, parental psychopathology, and family factors with hypothesized relationships with childhood anxiety. Findings suggested that children with SM experienced more anxiety than those in the community comparison group, with significantly higher levels of social anxiety, rumination, and physical symptoms reported. Mothers of children with SM reported greater monitoring of their children's activities, but they did not significantly differ from community comparison group mothers on reports of other parenting behaviors. Such findings may have important implications for guiding family involvement in psychosocial interventions.

A common genetic variant in the neurexin superfamily member CNTNAP2 is associated with increased risk for selective mutism and social anxiety-related traits

BACKGROUND

Selective mutism (SM), considered an early-onset variant of social anxiety disorder, shares features of impaired social interaction and communication with autism spectrum disorders (ASDs) suggesting a possible shared pathophysiology. We examined association of a susceptibility gene, contactin-associated protein-like 2 (CNTNAP2), for ASDs and specific language impairment with SM and social anxiety-related traits.

METHODS

Sample 1 subjects were 99 nuclear families including 106 children with SM. Sample 2 subjects were young adults who completed measures of social interactional anxiety (n = 1028) and childhood behavioral inhibition (n = 920). Five single nucleotide polymorphisms in CNTNAP2 (including rs7794745 and rs2710102, previously associated with ASDs) were genotyped.

RESULTS

Analyses revealed nominal significance (p = .018) for association of SM with rs2710102, which, with rs6944808, was part of a common haplotype associated with SM (permutation p = .022). Adjusting for sex and ancestral proportion, each copy of the rs2710102*a risk allele in the young adults was associated with increased odds of being >1 SD above the mean on the Social Interactional Anxiety Scale (odds ratio = 1.33, p = .015) and Retrospective Self-Report of Inhibition (odds ratio = 1.40, p = .010).

CONCLUSIONS

Although association was found with rs2710102, the risk allele (a) for the traits studied here is the nonrisk allele for ASD and specific language impairment. These findings suggest a partially shared etiology between ASDs and SM and raise questions about which aspects of these syndromes are potentially influenced by CNTNAP2 and mechanism(s) by which these influences may be conveyed.

P50 suppression in children with selective mutism: a preliminary report

Evidence suggests that children with selective mutism (SM) display significant aberrations in auditory efferent activity at the brainstem level that may underlie inefficient auditory processing during vocalization, and lead to speech avoidance. The objective of the present study was to explore auditory filtering processes at the cortical level in children with SM. The classic paired-click paradigm was utilized to assess suppression of the P50 event-related potential to the second, of two sequentially-presented clicks, in ten children with SM and 10 control children. A significant suppression of P50 to the second click was evident in the SM group, whereas no suppression effect was observed in controls. Suppression was evident in 90% of the SM group and in 40% of controls, whereas augmentation was found in 10% and 60%, respectively, yielding a significant association between group and suppression of P50. P50 to the first click was comparable in children with SM and controls. The adult-like, mature P50 suppression effect exhibited by children with SM may reflect a cortical mechanism of compensatory inhibition of irrelevant repetitive information that was not properly suppressed at lower levels of their auditory system. The current data extends our previous findings suggesting that differential auditory processing may be involved in speech selectivity in SM.

Treating youths with selective mutism with an alternating design of exposure-based practice and contingency management

Selective mutism is a severe childhood disorder involving failure to speak in public situations in which speaking is expected. The present study examined 9 youths with selective mutism treated with child-focused, exposure-based practices and parent-focused contingency management via an alternating treatments design. Broadband measures of functioning were employed, but particular focus was made on behavioral assessment of words spoken audibly and daily in public situations. Treatment ranged from 8 to 32 sessions and resulted in positive end-state functioning for 8 of 9 participants. Broader analyses indicated greater effectiveness for exposure-based practice than contingency management. The results support recent case reports of behavioral treatment for this population but in more rigorous fashion. Clinical and research challenges are discussed, including caveats about length and intensity of treatment for this population and need to develop standardized daily measures.

Silent suffering: understanding and treating children with selective mutism

Children with selective mutism (SM) restrict speech in some social environments, often resulting in substantial academic and social impairment. Although SM is considered rare, one or more children with SM can be found in most elementary schools. Assessment is performed to confirm the diagnosis, rule out psychological and medical factors that may account for the mutism, ascertain comorbid and exacerbating conditions needing treatment, and develop an intervention plan. Interventions are often multidisciplinary and focus on decreasing anxiety, increasing social speech and ameliorating SM-related impairment. Research is limited, but symptomatic improvement has been demonstrated with behavioral interventions and multimodal treatments that include school and family participation, as well as behavioral methods. Selective serotonin-reuptake inhibitors, especially fluoxetine, have also been found to be efficacious and merit consideration in severe cases. Persistence of some SM or anxiety symptoms despite treatment is common. Further development of treatments targeting specific etiological factors, comparative treatment studies and determination of optimal involvement of families and schools in treatment are needed to improve outcomes for children with SM.

Respiratory sinus arrhythmia and tympanic membrane compliance predict spontaneous eye gaze behaviors in young children: a pilot study

The Polyvagal theory proposes the Social Engagement System as a theoretical model linking social behavior with the neural regulation of the heart (via the vagus) and the striated muscles of the face and head (via special visceral efferent pathways). The current pilot study tested the feasibility of this model with typically developing 3-5-year-old children by evaluating the relation between spontaneous social engagement behavior measured by eye gaze behaviors and the visceromotor (e.g., respiratory sinus arrhythmia) and somatomotor (e.g., right tympanic membrane compliance) components of the Social Engagement System. Regression analyses supported the hypothesis that the visceromotor and somatomotor components of the Social Engagement System significantly predict social behavior (indexed by spontaneous eye gazes). Future studies assessing indices of visceral regulation and middle ear muscle function may provide insights into neural mechanisms mediating features of developmental disorders, such as autism, that have deficits in spontaneous eye gaze, auditory processing, and social behavior.