Abby Barnes’ hand shoots up nearly every time her teacher asks the 19 squirmy first-graders in her suburban Philadelphia public school to match letters of the alphabet to the sounds they make. Sitting up front with her pinchable cheeks framed by long blond hair, Abby, 7, looks as eager as any of her classmates to blurt out an answer. But every time the teacher calls on her, Abby freezes. Her face tightens. She strains to respond. And even if an answer manages to get past her lips, her words are inaudible. She’s effectively mute throughout the school day–even at recess, where the closest she will come to open communication is words whispered to a trusted girlfriend. At home, however, Abby is a different child. She loves to play cards and board games and frolic with her brother Jack, 5. “She speaks loudly–sometimes too loudly–and can be bossy toward her brother,” says mother Lisa Barnes, who runs the trading desk at a money-management firm. Abby is, in every other way, a perfectly normal child who has no shortage of extracurricular activities, including horseback-riding lessons and dance classes that she’s been attending since she was 4. “Performing in public is fine,” says her mother. “She likes people to look at her and applaud.” So why doesn’t she speak up in class? What may at first glance look like shyness or obstinacy is actually something far more complex–and much more interesting. Abby, like hundreds of thousands of kids across the U.S., is suffering from a little understood but increasingly recognized childhood disorder called selective mutism. The key to selective mutism, or SM for short, is the seemingly incongruous behavior Abby exhibits: voluble in private, silent in public. According to the official psychiatric diagnostic manual DSM-IV, a child who has developed normally at home but has not talked at school or in other social situations for at least a month is a strong candidate for a diagnosis of SM. Experts once believed that fewer than 1 in 1,000 kids developed the disorder, but an influential study three years ago in the Journal of the American Academy of Child and Adolescent Psychiatry put the prevalence at closer to 7 in 1,000, making SM almost twice as common as autism. SM can strike at any age, even among children who once talked in public, but it usually becomes obvious by age 3 or 4, when peers are happily jabbering away. About 30% of kids with SM also have a developmental speech impairment, which can exacerbate the problem but is generally not the cause. In the past doctors often recommended speech therapy, but treating the physical or neurological issues alone will probably have little impact on the underlying psychological factors behind SM. The root of the problem in most cases is an extreme form of social anxiety or phobia. “It is a fear that can literally make it impossible to speak,” says Dr. Elisa Shipon- Blum, a Philadelphia-based clinician who specializes in treating selective mutism. As with most social anxieties, SM is more common in girls and is believed to have a strong genetic component. About 70% of kids with SM have an immediate family member who also struggles with social anxiety.
