Most people who stutter begin stuttering in childhood, during the developmental period in which they are learning to communicate. In more rare cases, stuttering is the result of brain injury or severe psychological trauma.

When does a stutter develop?

Developmental stuttering.

It usually happens when a child is between ages 2 and 5. It may happen when a child's speech and language development lags behind what he or she needs or wants to say.

Where does stuttering come from in the brain?

In people who stutter, the brain regions that are responsible for speech movements are particularly affected.” Two of these areas are the left inferior frontal gyrus (IFG), which processes the planning of speech movements, and the left motor cortex, which controls the actual speech movements.