Vital Signs: Brain Got Your Tongue?

A 6-year-old girl cannot speak outside 
her home. Is she simply shy, or is some bigger problem keeping her from talking?

By Mark Cohen|Tuesday, June 14, 2011

RELATED TAGS: MENTAL HEALTH

My medical assistant put the chart on my desk. “your next patient is in room five, Dr. Cohen. Her name is Taylor and 
she’s a cutie!”

“Thanks, Mary,” I said, pulling up Taylor’s medical record on my desktop computer. I glanced at the consultation request: Six-year-old girl with speech problem. As a developmental pediatrician, I am often called on to evaluate children’s speech and language. Those are among the most complex tasks the young brain has to master, so it’s no wonder many childhood disorders express themselves in those areas. Kids with developmental delay or autism commonly show up in the pediatrician’s office with a parent who simply says, “My child isn’t talking.”

When I opened the door to the examining room, I saw a petite girl with long, blond hair sitting very still on the exam table. She wore a purple jumper over a short-sleeved white blouse, and her hair was tied at the back with a ribbon that matched her dress. She was deeply engrossed in reading a Dr. Seuss book. She looked up at me and smiled.

“Hi,” I said. “I’m Dr. Cohen. What’s your name?”

The girl continued to smile, but she didn’t say anything and quickly went back to her reading. Hmmm. Could just be a shy one, I thought. I turned to her mother.

“I understand your daughter is having some problems with her speech. Can you tell me what your concerns are?”

The mother was also petite and neatly dressed. She looked directly at me and said, “Well, she seems to have trouble talking.”

OK, maybe I was wrong. This was probably a child with some articulation problems. “What kind of trouble?” I asked.

The young woman grimaced slightly before answering. “Well, she, uh…she doesn’t talk.”

Maybe I wasn’t so wrong after all. Not talking is a complaint I hear from parents of children who turn out to have severe speech and language disorders. But those conditions generally declare themselves before age 6. Something was different here.

“Doesn’t talk?”

“No, not at all. At least that’s what her teacher says.”

“Her teacher? So she doesn’t talk at school?”

“Not a bit.”

“What about at home?”

The girl’s mother shook her head with a rueful grin. “At home I can’t shut her up! She talks a mile a minute.” She paused, and the grin faded. “I just don’t understand it.” Apparently Taylor’s pediatrician had not understood it either, but her mother had just given me the key. I was pretty sure I knew what was keeping this child quiet. Now I just needed a little more information to confirm my diagnosis.

“How about when she’s somewhere else, like the mall—does she talk then?”

“No, not a peep. When she was younger she talked all the time, and everywhere. Then when she was about 3 she started getting quiet. We would go out to eat and she wouldn’t say a word the entire time we were at the restaurant. At first we just thought she was shy and we encouraged her to talk, but she would just sit there. So we just gave up.”

I turned back to the girl. “Hi, Taylor! That’s a pretty dress you have on.” She looked at me with a faint smile. “I bet you like purple.” Her smile broadened. “Hey, your mom is wearing a purple skirt. Is it her favorite color too?” She nodded slightly, and then her smile faded and a wary look came into her eyes. Realizing I had made her uncomfortable by asking a question, I quickly shifted gears. “Green Eggs and Ham—I read that when I was a kid. I bet you like to read.” She smiled again and nodded vigorously.

“You see?” her mother asked with a worried expression. “This isn’t normal, is it?”

“No, it isn’t,” I said. “But I think 
I know what’s going on here and what we can do to help.” Strictly speaking, Taylor didn’t have a speech problem at all.

The telltale symptom was that Taylor talked perfectly well when she was at home but went silent when she was away from her familiar environment. She had a classic case of 
a condition called selective mutism.

I’ve had a handful of patients with selective mutism in my 30 years of practice, and I’ve seen our understanding of this condition increase dramatically over that time.

When I was in training, it was called elective mutism. The thought back then was that these children had been traumatized in some way, and then decided (“elected”) not to talk in certain settings. In the late 1980s, speech pathologists and psychologists began to recognize that these children often demonstrated other symptoms of social anxiety and that this was the root cause of their not speaking. In 1994 the name of the disorder was changed from “elective” to “selective” mutism, emphasizing that the child was not making a conscious decision to remain silent but was actually unable to speak in certain situations.

Selective mutism is relatively rare: One study found it in less than 1 percent of children referred to mental health professionals. It is different from simple shyness. A shy child may find it uncomfortable to talk with someone she doesn’t know, but she will usually manage to warm up, given time and support. A child with selective mutism truly cannot talk in some settings and will not improve over time without treatment.

Selective mutism is not a language disorder, either, since children communicate perfectly well when they are in their comfort zone. And it is completely different from autism. Although autistic children may interact more with familiar people than with strangers, they have severe problems with communication and social interaction no matter where they are. (Some children with selective mutism are mistakenly believed to be autistic by friends and family who don’t see them interacting and conversing perfectly well at home.)

Selective mutism is now considered by many clinicians to be a manifestation of a type of social anxiety or social phobia. A certain amount of anxiety is useful to keep us out of dangerous situations, but in anxiety disorders the perception of what is dangerous may be distorted.

Some researchers suggest that these disorders may be triggered by an imbalance of neurotransmitters in an area of the brain called the amygdala. The amygdala helps determine the emotional significance of things we perceive: “Uh-oh, is that somebody brandishing a knife—or just a bush moving in the wind?” Directors of horror movies are experts at manipulating this part of the brain.

Activity in the amygdala is regulated by at least three systems of brain chemicals called neuro­transmitters—serotonin, norepineph­rine, and GABA (gamma-amino butyric acid). An excess or deficiency in any of these neurotransmitters can affect the activity level of the amygdala and thereby influence how likely we are to perceive a given situation as threatening. For a child with selective mutism, being in a situation where she has to talk to someone she doesn’t know induces a feeling of terror, exactly as if she were facing genuine danger.

In addition to an imbalance in neurotransmitters, genetics, temperament, family dynamics, and environmental factors may also play a role in selective mutism, according to recent research. The relative contribution of each of these factors varies from child to child.

I referred Taylor to our practice’s child psychiatry department, where her treatment would include behavioral therapy aimed at decreasing social anxiety. This therapy takes advantage of the fact that the amygdala doesn’t respond just to the emotional neurotransmitter systems; it also receives messages from the cortical centers of cognition and judgment, which we can influence through rational thought.

One treatment method, called cognitive-behavioral therapy, helps 
a person to rethink a frightening situation and see it as something benign. When you can tell yourself, “Oh, that shape is just a bush, not a dangerous assailant,” that message is transmitted back to the amygdala and your level of panic drops significantly. Done repeatedly, this type 
of exercise can eventually help 
a patient overcome his or her fear 
of a particular situation.

Some children affected by selective mutism have such severe anxiety that in order to benefit from cognitive therapy, they may first require treatment with a medication such as fluoxetine (aka Prozac), which adjusts the levels of serotonin in the brain. Since there are so many factors involved in the condition, there is no one-size-fits-all treatment, but some combination of behavioral therapy and medical treatment seems to work for most children.

There are no good long-term studies of selective mutism, but I was optimistic about Taylor’s prospects. Published reports indicate that most children respond well to treatment and are able to speak in public within a few months, although some of them continue to experience significant symptoms of anxiety. 
Taylor had been diagnosed and referred for treatment relatively quickly. I was hopeful that within a year she would be able to stand in front of her class and read out loud from Green Eggs and Ham.

Mark Cohenis a developmental pediatrician with Kaiser Permanente in Santa Clara, California. The cases described in Vital Signs are real, but names and certain details have been changed.

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