Implanted medical devices—for example, cardiac defibrillators, deep brain stimulators, and insulin pumps—offer users the possibility of regaining some control over an increasingly unruly body, the opportunity to become part “cyborg” in service of addressing pressing health needs. We recognize the value and effectiveness of such devices, but call attention to what may be less clear to potential users—that their vulnerabilities may not entirely disappear but instead shift. We explore the kinds of shifting vulnerabilities experienced by people with Parkinson’s disease (PD) who receive therapeutic deep brain stimulators to help control their tremors and other symptoms of PD.