Abstract

Neurotechnologies are rapidly advancing in the past few years, such that neural prostheses and brain-computer interfaces are no longer things that only appear in science fiction movies. As interactions with neurotechnologies deepen, users have reported feeling that these tools are becoming part of their own selves and minds. The hypothesis of extended cognition can accommodate this intuition, as it maintains that artifacts can become a part of their users’ minds. However, there have also been some stark examples where users have abruptly lost access to their sophisticated tools, demonstrating the sometimes vulnerable and precarious nature of certain advanced technologies. These features seem to challenge the idea that users can stand in the right relation to their tools to meet the criteria of parity that support the extended cognition theorists’ arguments. Notably, these technologies seem to violate a condition of ownership that has been appealed to on various occasions over the past two decades of literature on extended cognition. In addition to arguing that neuroprosthetics can be a part of one’s extended cognitive system, despites apparent challenges to an ownership condition, we will also review the disparate history and evaluate the current status of the ownership criterion in the literature on extended cognition. To proceed, we first review the reasons for the origin of the proposed “ownership” criterion and, second, introduce new challenges arising from emerging technologies such as neuroprosthetics. We argue that the ownership condition has at least three shortcomings: (i) ambiguity of meaning, (ii) ethical pitfalls, and (iii) it fails to capture people’s intuitions about the cognitive status of emerging neurotechnologies. Ultimately, we argue that introducing the concept of co-ownership is a necessary distinction and is better suited to explain how advanced cognitive technologies function.