Content area
Abstract
Two studies were conducted to explore the relationship between selective mutism and anxiety disorders. There is an ongoing debate as to whether selective mutism should be considered a separate disorder or a symptom of social anxiety disorder. In the first study, the role of cortisol in symptoms of anxiety and selective mutism was investigated. 122 children aged 5-18 and their primary caregivers completed a number of questionnaires and participated in a low- and high- anxiety interactive speech task. Children provided salivary cortisol samples before and after the speech task. The results of the study indicated that children with selective mutism showed a pattern of cortisol reactivity distinct from both anxious and control children. Further, cortisol reactivity was significantly associated with both self- and caregiver-rated anxiety. The small effect sizes, as well as the complexity of the effects of cortisol, indicate that there are likely additional factors involved in regulating the relationship between cortisol and anxiety. Caregiving has been shown to influence children's behaviour and physiological reactions. Thus, the second study investigated the role of caregiving behaviours, specifically warmth, overcontrol, and criticism, as well as caregiver anxiety in helping to moderate the relationship between cortisol reactivity and behavioural anxiety. Caregiver and child behaviours were coded during the speech task. In response to a speech-related stressor, children showed more observable signs of anxiety, and caregivers showed more critical and overcontrolling behaviours and less warmth. Caregiving behaviours were associated with cortisol reactions for girls but not for boys, and did not act as a moderating variable in the relationship between cortisol and anxiety. Taken together, these results support the conceptualization of selective mutism as a unique anxiety disorder, similar to a specific phobia, rather than as a symptom of another anxiety disorder. The implications for the development of selective mutism and anxiety disorders are discussed, along with recommendations for prevention and intervention.
