A neural implant gives rats the ability to detect infrared light -- part of the electromagnetic spectrum normally invisible to them.

The implant takes the form of an infrared detector on the rat's forehead which is wired to a set of microscopic electrodes in a region of the animal's brain normally associated with touch. "The philosophy of the field of brain-machine interfaces has until now been to attempt to restore a motor function lost to lesion or damage of the central nervous system," said neurologist Eric Thomson, one of the authors of the study, in a press release. "This is the first paper in which a neuroprosthetic device was used to augment function -- literally enabling a normal animal to acquire a sixth sense."

The rats were initially trained to respond to lights in the visible part of the spectrum, poking their noses into a port near the light source for a reward. Once trained the infrared detectors were switched on meaning that when the rat faced the direction of the infrared source the touch region of the brain was stimulated.


Getting closer to the source would intensify the signal.

Essentially hotter/cooler as played using rat neurology.

At first the rats appeared to confuse the sensation with actual touch but over a month came to be able to use the augmentation to scan for and identify infrared light sources.


The study, published in the Nature Communications journal, also showed that, although the touch region of the brain adapted to allow the rats to process the infrared signals, the ability to sense touch was not impaired. That indicates that technologies to augment or restore senses in mammals could piggyback off related regions of the brain without damaging that area's original function.

Study leader Miguel Nicolelis of Duke University added that although the experiments had focused on whether rats could detect infrared sources at all there was no reason the technology couldn't be developed into full infrared vision or be expanded to include other areas of the electromagnetic spectrum. "We could create devices sensitive to any physical energy," said Nicolelis. "It could be magnetic fields, radio waves, or ultrasound. We chose infrared initially because it didn't interfere with our electrophysiological recordings."

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