The Brain as a Battlefield: Current Status, Opportunities, and Challenges of Defence-Relevant Neurotechnologies

The development of neurotechnologies, including different kinds of invasive and non-invasive neural interfaces, wearables, and neuromarketing techniques, is progressing at an accelerated pace. While practical and technical limitations remain, medical breakthroughs have enabled further advances and commercial neurotechnologies drive broader proliferation. However, civilian neurotechnologies, including medical and commercial, possess significant dual-use potential as they can be repurposed in defence contexts. As the cognitive domain becomes increasingly central to modern warfare, neurotechnologies have also shifted into the focus of defence actors due to their perceived and anticipated benefits for future military operations. Although defence-relevant neurotechnologies are at an even earlier stage, several applications are already crystallising, ranging from restorative and enhancing functions to more seamless forms of human–machine integration (HMI). Simultaneously, they introduce novel vulnerabilities and risks, and it remains yet to be seen whether their potential benefits outweigh associated costs. Considering the rapid pace of development and remaining uncertainties, this chapter assesses the current state of the weaponisation of neurotechnologies and its opportunities and challenges. The comparatively early stage of development and deployment of neurotechnologies provides a window of opportunity, including for European actors, to address emerging political, ethical, and legal issues of dual-use neurotechnologies through responsible governance and regulation.