The ‘Brussels 4’: essential requirements for implantable brain–computer interface user autonomy

<i>Objective</i>. Implantable brain-computer interfaces (iBCIs) hold great promise for individuals with severe paralysis and are advancing toward commercialization. The features required for successful clinical translation and patient adoption of iBCIs may be under recognized within traditional academic iBCI research and deserve further consideration.<i>Approach</i>. Here we consider potentially critical factors to achieve iBCI user autonomy, reflecting the authors' perspectives on discussions during various sessions and workshops across the 10th International BCI Society Meeting, Brussels, 2023.<i>Main results</i>. Four key considerations were identified: (1) immediate use, (2) easy to use, (3) continuous use, and (4) stable system use.<i>Significance</i>. Addressing these considerations may enable successful clinical translation of iBCIs.