## 4 Key Challenges and Development Trends
### Clinical Translation  
The clinical translation of BCI-based language decoding systems necessitates addressing multifaceted challenges to facilitate their integration into medical practice [128]. These challenges cover three primary dimensions, namely safety considerations, protocol standardization and validation procedures, and ethical frameworks, each requiring systematic attention for successful clinical implementation.  
Safety evaluation represents a primary concern, particularly for invasive BCI implementations in regard to language decoding applications. [PERSON] et al. conducted acomprehensive safety assessment of a fully implanted endovascular BCI in patients with severe paralysis, demonstrating promising safety outcomes [135]. This study, focusing on a device known as the Stentrode, underscores the critical importance of rigorous safety protocols, particularly in managing potential complications, such as infection risks and hardware reliability, during extended clinical deployment.  
Protocol standardization and validation procedures constitute interconnected requirements for clinical translation. Clinical viability demands robust empirical evidence, obtained through systematic testing in authentic medical environments. Recent research in the field emphasizes the significance of standardized protocols for EEG-based BCI user training, highlighting how structured methodologies enhance the consistency and reliability of the results [136]. These protocols enable systematic optimization of BCI systems for individual patients, while facilitating meaningful cross-study outcome comparisons.  
Ethical framework development represents the third critical dimension of clinical translation. A focused study has examined key ethical considerations surrounding BCI technologies, including privacy protection, patient autonomy, and informed consent procedures [137]. From a legal perspective, recent research by BROAL has further emphasized the critical need for robust data protection protocols and secure transmission mechanisms [138], as BCIs are increasingly vulnerable to security breaches that could compromise sensitive neural data. This legal dimension extends to the development of clear regulatory frameworks governing data handling and patient privacy rights. The social challenges in BCI deployment have been systematically examined by [PERSON] et al. [139] and [PERSON] et al. [140], in particular, highlighting issues of patient autonomy and social equity. Their work reveals that obtaining meaningful informed consent requires careful consideration, especially for patients with varying cognitive capacity, while also emphasizing the potential impact on human identity and the risk of exacerbating social inequalities through differential access to BCI technology. The ethical implications, as analyzed by [PERSON] et al., underscore the complex interplay between technological advancement and social responsibility, particularly regarding emerging challenges, such as cognitive enhancement applications and the need for international standardization of ethical guidelines [141]. These works collectively contribute to frameworks guiding the responsible deployment of BCI technologies in clinical settings, emphasizing the importance of addressing legal protections, social implications, and ethical considerations as interconnected aspects of successful clinical translation.  
The systematic resolution of these three key challenges, safety, protocol standardization and validation, and ethics, will significantly advance the clinical translation of BCI systems, ultimately expanding their therapeutic applications.