Machine Learning Takes on Brain-Computer Interfaces: The Brain-to-Text ‘25 Competition
For the next five months, machine learning enthusiasts and experts alike have a unique opportunity to make a significant impact in the realm of communication restoration for individuals suffering from neurodegenerative diseases. The Brain-to-Text ‘25 competition invites participants to develop algorithms aimed at translating neural signals from a brain-computer interface (BCI) user into coherent speech. The competition has a clear goal: to achieve the best word prediction accuracy and claim a $5,000 prize.
What is Brain-to-Text ‘25?
This annual competition is an initiative by the Neuroprosthetics Lab at the University of California, Davis, and part of the BrainGate consortium, which has been at the forefront of BCI research since the early 2000s. Participants will be working with data collected from 46-year-old Casey Harrell, who, due to amyotrophic lateral sclerosis (ALS), lost his ability to speak intelligibly. This competition builds upon the groundwork laid by a previous challenge hosted by researchers from Stanford University.
The Challenge Before Competitors
Competitors will be required to decode words from Harrell’s brain data by first identifying phonemes—the distinct units of sound that make up speech. Following this, the algorithms must translate these sounds into meaningful words. The training data comprises nearly 10,948 sentences that Harrell attempted to articulate, which will be crucial for algorithm development.
However, the real test lies in predicting words from 1,450 withheld sentences. The performance of the competing algorithms will be assessed based on the word error rate; the fewer the errors, the better the proposed solution.
Setting the Benchmark
Historically, the previous competition set the bar with a starting word error rate of 11.06%, and the winning algorithm achieving a remarkable 5.77%. This year, the UC Davis team has established a new standard with their advanced algorithm, reporting a word error rate of 6.70% to beat.
The Importance of Collaboration
Nick Card, a postdoctoral researcher leading the project, emphasized the competition’s collaborative spirit. He believes in sharing data with the public to foster innovation rather than keeping it confined to research labs. This open-source approach aims to accelerate advancements in BCI technology, bringing it closer to practical applications for those who need it most.
Insights from Experts
The invitation to participate in such a competition has been hailed as a crucial step in the BCI field by experts like Konrad Kording from the University of Pennsylvania. Kording, who researches machine learning applications in neuroscience, views this as an overdue development in making research more accessible and inclusive.
Ethical Considerations and Patient Confidentiality
Despite the excitement surrounding the integration of machine learning and BCI research, ethical concerns regarding data privacy persist. Bioethicist Veljko Dubljević points out potential risks associated with publicizing brain data, particularly the long-term implications of patient identification through data analysis advancements.
Fortunately, in Harrell’s case, these concerns are mitigated as he has publicly shared his journey and experiences. This transparency is essential for allowing researchers and developers to ethically engage with BCI technology.
The Personal Impact of BCIs
BCIs hold the potential to bridge the gap between technology and the most intimate aspects of human experience—speech and communication. As Dubljević articulates, speech holds a significant place within a person’s identity, and thus, the implications of these technologies go beyond mere functional restoration; they touch upon personal agency and emotional well-being.
The Competition’s Structure and Incentives
Beyond the excitement of cutting-edge technology, the Brain-to-Text ’25 competition also introduces cash awards. Two monetary prizes will be awarded for the lowest word error rates, with amounts of $5,000 and $3,000. An additional award of $1,000 will be given for the most innovative solution, aimed at encouraging creativity over formulaic, high-cost strategies.
Who Will Prevail?
The competition spectrum can vary greatly—not just traditional BCI researchers but also those dubbed as “street fighters” in machine learning who might lack prior BCI experience. These competitors often rely on speed and agility within algorithmic processes, showcasing that diverse approaches can lead to unforeseen breakthroughs in this field.
The Road Ahead
As the competition progresses, it will be fascinating to witness how various teams navigate the challenge of decoding speech from brain data in real-time. The dynamic interplay of innovation, ethical considerations, and the urgency of patient communication restoration creates a compelling narrative that is likely to inspire future advancements in BCI technology.
With its foundation in collaboration and public engagement, the Brain-to-Text ‘25 competition stands as a testament to the power of machine learning in tackling some of humanity’s most pressing challenges. As participants delve into this intricate puzzle, they pave the way for transformative solutions that could redefine communication for those affected by debilitating conditions.

