How does one ensure information security for a computer that is entangled with the structures and processes of a human brain - and for the human mind that is interconnected with it? The need to provide information security for neuroprostheses grows as more people utilize cochlear implants, retinal prostheses, robotic prosthetic limbs, and deep brain stimulation devices. Moreover, emerging technologies for human enhancement are expected to transform users' sensory, motor, and cognitive capacities in ways that generate new 'posthumanized' sociotechnological realities. This volume investigates these topics at both the theoretical and practical levels. It presents a cognitional security framework for protecting a device's human host as a sapient metavolitional agent, embodied embedded organism, and social and economic actor and applies a range of preventive, detective, and corrective security controls to neuroprostheses, their host-device systems, and the larger supersystems in which they operate.