Beacon Biosignals is revolutionizing neurological research and diagnostics by monitoring brain activity during sleep. Founded by Jake Donoghue and Jarrett Revels, the company developed a lightweight headband that utilizes electroencephalogram (EEG) technology to capture clinical-grade brain data while patients sleep at home. This approach transforms sleep from a constrained, facility-based procedure into a scalable source of high-quality data for diagnostics, drug development, and the monitoring of brain health. The device has received FDA 510(k) clearance and has been deployed in over 40 global clinical trials. These studies focus on conditions such as major depressive disorder, schizophrenia, narcolepsy, Alzheimer's disease, and Parkinson's disease. By partnering with pharmaceutical companies, Beacon enables less invasive observation of how treatments affect the brain and how patients respond over time. Donoghue, who holds a PhD in neuroscience from MIT and an MD, founded the company in 2019 after recognizing a critical gap in medical care. While cardiologists can easily monitor heart function long-term from home, neurological assessment often relies on static or episodic measures. Beacon aims to apply similar longitudinal data-driven precision to brain health. The company believes that neural activity during sleep is more structured and informative, acting as a window into brain function and the effects of potential therapies. Using machine learning algorithms, Beacon processes the collected data to identify subtle changes in sleep architecture, such as the duration of specific sleep stages and frequency of awakenings. These features can signal early cognitive decline or disease progression long before clinical symptoms appear. The goal is to build a comprehensive "foundation model" of the brain by correlating these dynamic data points with disease outcomes, potentially identifying new subgroups of patients and tracking disease heterogeneity in ways that sequencing or imaging cannot. Strategic moves have accelerated Beacon's expansion. Last year, the company acquired a home sleep apnea testing provider serving over 100,000 patients annually, significantly broadening its user base. In November, Beacon secured $97 million in funding to further scale its platform. This financial backing supports the vision of creating a longitudinal record of brain function for millions of users. Donoghue emphasizes that routine testing can evolve into a powerful diagnostic tool. For instance, data collected for sleep apnea screening could serve as an early warning system for neurodegenerative diseases like Parkinson's years before symptoms manifest. By converting everyday sleep into a continuous monitoring tool, Beacon aims to shift the paradigm from late recognition to early, data-driven detection and intervention, ultimately improving treatment outcomes for neurological disorders on a global scale.