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

• Published in: Journal of Neural Transmission Vol. 128; no. 9; pp. 1433 - 1443
• Main Authors: Melfsen, Siebke, Romanos, Marcel, Jans, Thomas, Walitza, Susanne
• Format: Journal Article
• Language: English
• Published: Vienna Springer Vienna 01.09.2021
• Subjects: Adolescent; Anxiety; Anxiety Disorders; Child; Child Behavior Disorders; Female; Humans; Medicine; Medicine & Public Health; Mutism; NCT; NCT04233905; Neurology; Neurosciences; Psychiatry; Psychiatry and Preclinical Psychiatric Studies - Original; Psychiatry and Preclinical Psychiatric Studies - Original Article; High sensory-processing sensitivity; Selective mutism; Anxiety; Schoolchildren; Dissociation; Aetiology
• ISSN: 0300-9564; 1435-1463
• DOI: 10.1007/s00702-021-02404-1

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 [ X 2 (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.