From Scientific American:
Scientists have come a step closer to gaining complete control over a mind, even if that mind belongs to a creature the size of a grain of sand. A team at Harvard University has built a computerized system to manipulate worms—making them start and stop, giving them the sensation of being touched, and even prompting them to lay eggs, as seen in the video above—by stimulating their neurons individually with laser light, all while the worms swim freely in a petri dish. The technology may help neuroscientists for the first time gain a complete understanding of the workings of an animal's nervous system.
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