1. A medical device system that provides treatment therapy for a nervous system disorder, comprising: an implantable component configured to be implanted within a patient body and operate according to a first treatment therapy mode; and a first external component configured to be positioned external to the patient body, generate a signal indicating the presence of the first external component to the implantable component, and provide a second treatment therapy mode; the implantable component further configured to receive the signal from the first external component and detect that the first external component is present based on receiving the signal, the implantable component further configured to detect that the first external component is not available based on not receiving the signal, the implantable component further configured to begin operating in conjunction with the first external component according to the second treatment therapy mode if the implantable component detects that the first external component is present, and stop operating according to the second treatment therapy mode if the implantable component detects that the first external component is not present.