With the help of surface electromyography, a child suffering from facial nerve impairment can smile again.

Many people who suffer from facial nerve impairment can benefit from surface electromyography (SEMG). SEMG is a noninvasive test that checks the activity of muscles and nerve control.

In cases such as a four-year-old boy who sustained seventh cranial nerve palsy at birth, rehabilitation using SEMG improved his ability to use his facial muscles.

Cranial nerve palsy is a nervous system disorder where a damaged nerve in the skull affects the movement of facial muscles. In the young boy's case the muscles on the left side of his face were affected. His paralysis not only affected his smile, but also his ability to eat and close his left eye.  

During his SEMG therapy, sensors were placed on his skin to record the appropriate targeted muscle activity. He was given incentives when he successfully used specific facial muscles. When the young boy would appropriately react to treatment, a DVD would activate playing a desired movie. If the response was not repeated, the DVD would stop.  A "good smile" would activate the DVD.  

Through fourteen one-hour sessions using SEMG, the boy learned how to control his facial muscles. He improved his ability to hold a smile from 11.2 seconds to 66.5 seconds.

Nearly 70 percent of people who suffer from facial nerve impairments naturally overcome their condition. However, when factoring in paralysis during pregnancy that number decreases to 61 percent. If recovery does not occur within six months of the beginning of paralysis, the result is poor. One of the most challenging issues in cranial nerve palsy is the frequency of "synkinesis," which is the involuntary movement of muscles or limbs. For instance during an individual's attempt to smile, one's eye may close. It can also affect oral functioning, taste and protection of the cornea.

The study was published in the journal Biofeedback