Abstract This article presents findings from a first-in-human trial involving implantation of a Brain–Computer Interface (BCI) into a quadriplegic patient. It explores the psychological consequences of being integrated into a continuous BCI feedback loop, focusing on how such intimate interaction can enhance users’ sense of empowerment and ownership. At the same time, it reveals complex ethical tensions surrounding the notions of agency and control. Our results suggest that prolonged engagement with BCIs can lead to a profound sense of integration—where users begin to perceive themselves as part of the system. While this can foster a heightened sense of control, it also introduces risks such as psychological disruption and distress, particularly when users are abruptly disconnected from their devices or the device generates false positives (e.g. the device producing unintended outcomes). A key insight from our study is the emergence of what we term being-of-the-loop —a condition in which a symbiosis develops between the user and the AI system, giving rise to a de novo agency that neither could achieve alone. In this state, the BCI is no longer experienced as an external tool but as a constitutive part of the self, fundamentally reshaping how users perceive control, authorship, and action. While this integration can foster empowerment and restored capabilities, it also creates a fragile dependence: agency becomes entangled with the system’s functioning, rendering users vulnerable to false positives and identity disruption when the loop is severed. These findings raise urgent ethical concerns about psychological rupture and the risks of disconnecting a technology that has become embedded within—and transformative of—the user’s lived experience.