Brain-imaging techniques have revealed the brain’s plasticity and have identified networks that music activates. The brain areas activated by music are not unique to music. These networks also process other functions. Musical and non-musical functions share systems. For example, motor control and executive control share circuits with music. Music can activate and drive complex patterns of interaction between the other two, so that a stroke patient and someone with Parkinson’s increases movement, and someone with traumatic brain injury increases cognitive functioning, such as problem solving or decision making.