Consent in flux: when brain‑computer interface embodiment undermines informed consent

In March 2026, China approved the first invasive brain‑computer interface (BCI) for clinical use globally. While this milestone accelerates neurotechnology translation, it exposes a neglected ethical problem: in some long-term invasive BCI cases, participants who initially consent to later device explantation may subsequently develop functional dependence on, and phenomenological incorporation of, the device. This paper examines whether such post-implantation integration can weaken the continuing moral authority of initial consent to explantation.

This paper provides a normative analysis grounded in established bioethics concepts. We draw on theories of extended cognition and transformative experience, integrate findings from qualitative empirical studies of BCI user phenomenology, and engage with the neurorights discourse and Chinese regulatory developments. The analysis focuses on the moral authority of initial consent where long-term device integration may alter the participant's embodied agency, with particular attention to the implications for interpreting the right to withdraw from research.

Transformative experience alone is not sufficient to distinguish implantable BCIs from other medical interventions that may also alter self-understanding. The distinctive diachronic consent problem arises when ex ante experiential ignorance is combined with extended cognition, embodied agency, functional dependence, and the possibility that explantation would remove a device experienced as part of the user's agential system. We identify a specific governance gap in China's current ethical guidelines and propose three interlocking reforms: adopting a dynamic consent model with periodic re‑consent encounters, establishing ongoing ethical review for implanted participants, and decoupling withdrawal from research from consent to explantation. An ethical algorithm to guide explantation decisions is presented.

Informed consent for long-term invasive BCI use should be reconceptualised as an ongoing process where there is evidence of functional dependence or phenomenological incorporation. Initial consent remains important, but it should not be treated as conclusively authorising later explantation without post-integration reassessment.