On Thursday, OpenAI announced its investment in neurotech startup Merge Labs, cofounded by its CEO, billionaire Sam Altman. Merge Labs has raised $252 million in funding from OpenAI, private investment firm Bain Capital, video game developer Gabe Newell, and others to use ultrasound to read and modulate the brain. In contrast to Neuralink, Merge says it will not implant its technology in the brain. Most brain-computer interfaces, including those from Neuralink and Synchron, measure electrical activity directly from neurons. In addition to Altman, Merge Labs’ cofounders include researchers Mikhail Shapiro, Tyson Aflalo, and Sumner Norman, as well as tech entrepreneurs Alex Blania and Sandro Herbig.