Quezi

Photo by Peter Maninski - CC-BY

In an earlier article, we looked at ways in which scientists could control the movement of rats and other animals by radio control. Those ratbots were living animals with electrodes implanted in their brain and connected to a radio control receiver. Now we look at the reverse situation – using the brain cells of a rat (without a rat’s body) to control an electrical robot, creating an animat.

Researchers from Reading University and elsewhere have been experimenting with artificial “brains” made from real rat brain cells. Here’s how it works.

First the team cuts out the neural cortex from a rat fetus, and applies enzymes that disconnect all the neurons from each other. Then they place the neurons in a nutrient-filled pot, where the neurons regrow a dense network of connections to other neurones, much as they do inside the brain.

It turns out that the electrical patterns in this artifically-grown rat brain are measurable and interesting. Reading University’s Ben Whalley says the neuron pot is like a “creature with no limbs or senses, the cut-down brain is simply bursting out of boredom”.

Under the neuron pot is an array of electrical connections so that the researchers can interface with the brain. It’s possible to wire up different parts of the brain to enable it to control the robot. For example, if it is found that one part fires when a certain signal is present, that response can be used to navigate the robot around obstacles.

Researchers at Reading and Georgia Tech have achieved 80% and 90% success rate for obstacle avoidance using this connection to the rat brain cells (see it on video). Different rat brain cultures behave slightly differently, which manifests itself as “personality” with some of the brains driving the robot more aggressively than others.

Stimui can be applied repetitively to cause certain behaviours to become embedded in the culture for a few hours. The culture is “learning”. Georgia Tech’s Steve Potter says it’s like training an animal.

The researchers hope that the knowledge gained from their experiments might prove useful in the treatment of epilepsy and alzheimers disease.

And is the animat conscious? That’s a difficult question to answer. We can’t even say for certain that a rat is conscious, although it probably is. We simply don’t know enough about the nature of consciousness to be able to answer this question. What we can say, though, is that if this pot of neurons is conscious, it’s not the consciousness of a rat but rather the consciousness of a pot of neurons.