Neurons in a dish learned to play Pong

Researchers at Cortical Labs in Melbourne grew cultures of about 800,000 human or mouse neurons on a grid of electrodes, then wired the dish into a simplified version of Pong, feeding the cells electrical signals that stood in for the ball's position.

The neurons' own electrical activity controlled the paddle, and the cells received a predictable electrical pattern when they hit the ball and an unpredictable one when they missed. Within about five minutes of play, the neurons began adjusting their activity in ways that improved the paddle's performance, a change the researchers described as a basic form of learning.

The team called the system DishBrain and described the result as a form of sentience, a word other neuroscientists criticized, since what the dish showed was goal-directed activity under a feedback loop, not awareness or intent. The finding has pushed a small new field, sometimes called synthetic biological intelligence, that treats cultured neurons as a possible computing substrate.

Neurons in a dish, improving at a game.