To do so, the researchers used a cheap, lightweight computer chip with a wireless receiver to transmit a signal to the roaches. Imagine the roaches strapped with a tiny backpack and you get the picture. The device weighs only 0.7 grams and includes a microcontroller that monitors the interface between implanted electrodes and tissue so the roach's nervous system doesn't fry.
The device is also wired to the cockroach's antennae and cerci, its sensory organs in the abdomen. The cerci detect movement in the air to detect predators and cause roaches to scurry. However, by using wires to stimulate the cerci, researchers were able to trick the roach into thinking something was sneaking up on it, thus causing it to move.
Wires attached to the antennae are essentially reins that feed small charges into the roach's neural tissue, which fool the roach into thinking there is something they need to steer clear of. In doing so, researchers were able to steer the roach along a curved line.