Neurons grown in a Petri dish are able to learn how to play Pong, the great classic of video games, thus demonstrating a “intelligent and sentient behavior“, according to Australian neuroscientists. This study, published in the scientific journal Neuron, paves the way for a new kind of research that could one day use neurons to process information, a kind of biological machines that would support digital computers, according to lead researcher Brett Kagan. “Machines can’t learn things very quickly. For a “machine learning” algorithm. (machine learning, an artificial intelligence technique, ed) to learn something, it needs thousands of data samples“, he explained. While“A dog can learn a trick in two or three attempts“, He observes.
Neurons connected to microelectrodes
Neurons are the foundation of intelligence in all animals, from insects to humans. For their experiment to find out whether it was possible to harness the intrinsic intelligence of neurons, Brett Kagan and his colleagues took neurons from mouse embryonic brains and neurons from adult human stem cells. They then cultured these neurons around microelectrode arrays that could detect their activity and stimulate them. The experiments involved clusters of about 800,000 neurons, the size of the brain of a hornet.
In a sort of simplified version of the game of tennis Pong, a signal was then sent from the right or left to indicate the position of a ball and the cluster of neurons, nicknamed by researchers “DishBrain” (or brain in box in French), he responded with another signal to move the racket.
Neurons play to make their environment predictable
One of the main obstacles was figuring out how to make neurons learn a task. Previous work has suggested giving them a dose of the dopamine “happiness hormone” with each correct action, but this has proved difficult to achieve as quickly as necessary. Instead, Dr. Kagan’s team relied on the so-called “free energy principle” theory introduced more than a decade ago by Karl Friston, the lead author of the study, and according to which cells instinctively try to minimize the unpredictability of their environment.
When the neurons managed to hit the ball using the racket, they then received predictable information indicating their success. But when they were missing, the signal received was random, unpredictable. “The only way neurons could keep their world controllable and predictable was to be more successful in hitting the ball.“detailed Brett Kagan. His team believes DishBrain is”sensitive“- what they define as being able to perceive sensory information and respond to it dynamically – but not go so far as to talk about it”awareness“, which implies being aware of one’s existence.
A brain in a box
This “brain in the box” has even tried the game that replaces Google’s search engine in the absence of an internet connection, which involves running a dinosaur through obstacles, and the first results were encouraging, said Brett Kagan. Scientists next want to test how drugs and alcohol affect the intelligence of these neurons, but Dr. Kagan is mostly excited about the possibility of developing biological computers. “It is (a) rigorous and interesting neuroscience experiment“estimates Tara Spiers-Jones, of the University of Edinburgh, who was not involved in the study.”Don’t worry, although these neuron boxes can alter their responses when stimulated, they are not science fiction type intelligence boxes, they are simple (though interesting and important) from a scientific point of view) circuit responses.“, He reassures.