The Breakthrough Devices Program, established by the FDA, aims to expedite the development and review of innovative medical technologies that address life-threatening or irreversibly debilitating conditions. Key benefits include:

• Priority review of regulatory submissions

• Enhanced communication with FDA experts

• Flexible clinical study design options

• Dedicated FDA review team support

As of December 31, 2023, the FDA had granted 933 Breakthrough Device designations, with 921 from the Center for Devices and Radiological Health (CDRH) and 12 from the Center for Biologics Evaluation and Research (CBER)1. The program reflects the FDA's commitment to fostering device innovation while maintaining rigorous safety and effectiveness standards2.

Blindsight, Neuralink's experimental vision-restoring implant, aims to enable sight for individuals who have lost both eyes and optic nerves, and potentially even those blind from birth1. The device utilizes a microelectrode array embedded in the visual cortex to stimulate neurons with patterns derived from a camera2. While this approach builds on decades-old technology, Neuralink's innovation lies in increasing electrode density, potentially improving the quality of visual perception. However, experts caution that restoring functional vision, especially for those blind from birth, remains a complex challenge requiring extensive adaptation and training2.

The breakthrough device designation for Blindsight does not guarantee FDA approval or proven effectiveness, but it does offer several advantages for Neuralink. These include priority review, enhanced communication with FDA experts, and potential flexibility in clinical study design12. However, the device must still meet rigorous safety and efficacy standards before it can be marketed. While Elon Musk has made ambitious claims about Blindsight's potential to restore vision even for those blind from birth, experts caution that such outcomes are highly speculative at this stage and that developing functional vision, especially for congenitally blind individuals, remains a complex challenge3.

Vision restoration through cortical implants like Neuralink's Blindsight faces significant technological challenges that go beyond simple engineering. The fundamental issue lies in the complexity of the human visual system and how neurons in the visual cortex process information12.

• Neurons are not pixels: Unlike computer screens, where more pixels equal better resolution, neurons in the visual cortex have complex receptive fields that respond to specific patterns of light13.

• Electrode limitations: Even with 45,000 electrodes, each stimulating a single neuron, the resulting image would be significantly blurrier than a 45,000-pixel display24.

• Neural code complexity: Recreating natural vision requires stimulating thousands of neurons with precise patterns, which is currently beyond our technological capabilities25.

These challenges suggest that while cortical implants may provide some level of visual perception, achieving resolution comparable to or exceeding normal human vision remains a distant goal36.

Founded in 2016, Neuralink aims to develop brain-chip interfaces that can be implanted in the skull to help disabled individuals regain abilities such as movement and communication1. The company's chips process neural signals and can connect to external devices like computers or smartphones. Currently, Neuralink is also testing a brain implant to help paralyzed patients control digital devices using their thoughts, with three patients enrolled in a trial expected to last several years1. Earlier this year, the company successfully implanted its chip in a second patient, who is now using it to play video games and design 3D objects1.

Despite the potential of Neuralink's Blindsight device, several concerns and criticisms have been raised:

• Safety and long-term effects: The long-term impacts of neural implants are not fully understood, necessitating careful monitoring for adverse effects1. There are risks associated with brain surgery and potential tissue damage from the implant.

• Ethical considerations: Questions arise about data privacy, potential misuse for non-medical purposes, and the implications of enhancing vision beyond normal human capabilities2. There are also concerns about equitable access, as the technology may exacerbate healthcare disparities2.

• Technical challenges: Maintaining signal quality and electrode performance over time remains difficult, with studies showing decreased effectiveness in long-term implants2. Additionally, restoring functional vision, especially for those blind from birth, is a complex challenge requiring extensive adaptation and training3.