Human brain cells in a dish have learned to play Pong. 

A Melbourne-led team has for the first time shown that 800,000 brain cells living in a dish can perform goal-directed tasks – in this case the simple tennis-like computer game, Pong.

To perform the experiment, the research team took mouse cells from embryonic brains as well as some human brain cells derived from stem cells and grew them on top of microelectrode arrays that could both stimulate them and read their activity. They named their creation ‘DishBrain’.

Electrodes on the left or right of one array were fired to tell DishBrain which side the ball was on, while distance from the paddle was indicated by the frequency of signals. 

Feedback from the electrodes taught DishBrain how to return the ball, by making the cells act as if they themselves were the paddle.

The researchers say they are now going to find out what happens when their DishBrain is affected by medicines and alcohol.

“We have shown we can interact with living biological neurons in such a way that compels them to modify their activity, leading to something that resembles intelligence,” says lead author Dr Brett Kagan, who is Chief Scientific Officer of biotech start-up Cortical Labs, dedicated to building a new generation of biological computer chips. 

“DishBrain offers a simpler approach to test how the brain works and gain insights into debilitating conditions such as epilepsy and dementia,” says Dr Hon Weng Chong, Chief Executive Officer of Cortical Labs.

While scientists have for some time been able to mount neurons on multi-electrode arrays and read their activity, this is the first time that cells have been stimulated in a structured and meaningful way.

“In the past, models of the brain have been developed according to how computer scientists think the brain might work,” Dr Kagan says. 

“That is usually based on our current understanding of information technology, such as silicon computing.

“But in truth we don’t really understand how the brain works.”

By building a living model brain from basic structures in this way, scientists will be able to experiment using real brain function rather than flawed analogous models like a computer.

Dr Kagan and his team, for example, will next experiment to see what effect alcohol has when introduced to DishBrain.

“We’re trying to create a dose response curve with ethanol – basically get them ‘drunk’ and see if they play the game more poorly, just as when people drink,” says Dr Kagan.

That potentially opens the door for completely new ways of understanding what is happening with the brain.

“This new capacity to teach cell cultures to perform a task in which they exhibit sentience - by controlling the paddle to return the ball via sensing - opens up new discovery possibilities which will have far-reaching consequences for technology, health, and society,” says Dr Adeel Razi, Director of Monash University’s Computational & Systems Neuroscience Laboratory.

“We know our brains have the evolutionary advantage of being tuned over hundreds of millions of years for survival. Now, it seems we have in our grasp where we can harness this incredibly powerful and cheap biological intelligence.”

Researchers are also working on creating an alternative to animal testing when investigating how new drugs or gene therapies respond in these dynamic environments.

More details are accessible here.