Researchers are still studying the underlying causes of persistent stuttering. A combination of factors may be involved. Possible causes of persistent stuttering include:
Abnormalities in speech motor control. Some evidence indicates that abnormalities in speech motor control, such as timing, sensory and motor coordination, are implicated.
Genetics. Stuttering tends to run in families. It appears that stuttering can result from inherited (genetic) abnormalities in the language centers of the brain.
Medical conditions. Stuttering can sometimes result from a stroke, trauma or other brain injury.
Mental health problems. In rare, isolated cases, emotional trauma can lead to stuttering.