Parasma

Parasma is a San Francisco biological compute company led by founder Sean Cole. It writes the algorithms and infrastructure that turn living neurons into programmable compute: a sentence becomes electrical stimulation, cultured human brain cells carry the context, and their responses are decoded directly into tokens with a feedback signal for correctness. The company first demonstrated the approach end to end by training cultured neurons to play Doom.

It joined Y Combinator's Summer 2026 batch, raised a 500000 dollar seed from the accelerator, and launched publicly in August 2026 reporting that its cells correctly predicted 90 percent of next-token decisions with full sentence context, one non-linear run reaching 78.1 percent against the 75 percent ceiling of a silicon linear decoder. Its near-term goal is repeatable benchmarks across cultures, devices, and time, aimed at organizations that hit power, cooling, or training-data ceilings before accuracy limits.