The findings indicate that invasive BCIs offer strong motor and sensory restoration, with robotic arm control reaching 80% to 100% task success rates and partial recovery of hand movement, but are limited by surgical hazards, progressive signal deterioration and price tags above $250,000. Non-invasive BCIs are safer and have seen wider deployment in community-based neurorehabilitation, with around 70% effectiveness for post-stroke upper-limb recovery, yet they struggle with inherently poor signal-to-noise ratios, a BCI illiteracy rate near 30% and low information transfer speeds.
The assessment also highlights mounting ethical and societal strains, including neural data privacy, autonomy paradoxes, inequitable access, stigmatization and military coercion. The study stresses embedding relational autonomy and neural rights into BCI development, while current trends include the domestication of non-invasive systems, multimodal sensor fusion and adaptive algorithms.