Brain-computer interfaces (BCIs) enable direct communication between the brain and external devices. They hold promise for treating neurological disorders, restoring motor function, and enhancing human-computer interaction. Although non-invasive BCIs dominate research due to their accessibility and safety, advances in invasive and minimally-invasive technologies have improved signal fidelity and expanded applications. Despite these advancements, ethical concerns such as data privacy, informed consent, mental autonomy, and potential misuse must be addressed to ensure responsible implementation. Regulatory frameworks have been struggling to keep pace with rapid technological progress, raising concerns about safety, standardization, and long-term viability. Practical barriers such as high costs, limited accessibility, and the need for specialized training further complicate deployment. Additionally, the long-term neural impact of invasive BCIs and their seamless integration into daily life remain areas of active investigation. This review provides a comprehensive overview of the current BCI landscape. It examines foundational biosignals and technological approaches, highlights groundbreaking applications in healthcare (including neuroprosthetics, rehabilitation, and cognitive enhancement), and offers a critical analysis of the ethical, regulatory, and technical challenges. Ultimately, the review reflects the immense transformative potential and the multifaceted complexities of BCIs, emphasizing the imperative for responsible innovation and robust interdisciplinary collaboration to navigate their future development.
Li et al. (Tue,) studied this question.