Group 1 - The core concept of brain-machine interfaces (BMIs) involves inserting electrodes into the brain to detect electrical signals that correspond to intended actions, enabling patients to regain movement and control devices [10][12][15] - Neuralink, founded by Elon Musk, has developed an invasive BMI procedure that involves inserting over 1,000 electrodes into the brain, allowing patients to perform tasks such as playing video games [3][40] - Other companies, such as BrainGate and Huatuo Technology, are also making advancements in the BMI field, helping patients with paralysis regain control over their movements and interact with technology [5][7][49] Group 2 - BMIs can be categorized into non-invasive, semi-invasive, and invasive types, with each type varying in signal quality and application [18][24][36] - Non-invasive BMIs, like EEG devices, are widely used but have limitations in signal quality compared to semi-invasive and invasive options [17][23] - Invasive BMIs, while offering the highest signal quality and precision, face challenges such as biocompatibility and the need for advanced materials to minimize damage to brain tissue [48][51][54] Group 3 - The development of flexible microelectrodes is crucial for the success of invasive BMIs, as they must be soft enough to avoid damaging brain tissue while maintaining signal integrity [51][53] - The challenge of miniaturizing BMI devices is significant, as current devices still require a substantial opening in the skull for implantation [58][62] - Data transmission bandwidth is a critical issue for BMIs, with current technologies needing to improve to support the high data rates required for full-brain interfaces [62][64]