Researchers Develop Sense of Infrared Sight in Rats With Goal of Bringing Visible Sight to Blind People (w/video)

Extra-sensory systems for the blind have the potential to replace eyes with another sense, and some have been built that essentially turn video into sound or tactile sensation. Now researchers at Duke University Medical Center are reporting in Nature Communications that they were able to create a system that combines an infrared camera and a brain implant to let rats sense infrared light, which they otherwise don’t perceive.

Implanted intracortical microstimulation neuroprostheses placed onto the somatosensory cortices of rat brains were hooked up to little infrared cameras on their heads. Whenever the camera would see infrared light, the prostheses were activated. Not long after getting used to their new gear, the rats were able to find food by looking for a bin that had an infrared light go on.

Here are a couple videos showing rats “seeing” infrared light:

The IR light comes on, and when the rat orients toward the stimulus, an IR-signal is registered by an IR-detector on the rat’s head, and S1 is stimulated with a frequency that depends on detector’s output. Guided by microstimulation, the rat approaches the reward port to receive water. In the floor-level view, you can see the infrared detector attached to the rat’s head. The audio track is the output of the microstimulator, which is not available to the rat.

 

Movie shows three trials in a well-trained rat navigating the chamber actively foraging for IR sources. The ports are 90 degrees apart.

From the study abstract:

Here we show that adult rats can learn to perceive otherwise invisible infrared light through a neuroprosthesis that couples the output of a head-mounted infrared sensor to their somatosensory cortex (S1) via intracortical microstimulation. Rats readily learn to use this new information source, and generate active exploratory strategies to discriminate among infrared signals in their environment. S1 neurons in these infrared-perceiving rats respond to both whisker deflection and intracortical microstimulation, suggesting that the infrared representation does not displace the original tactile representation. Hence, sensory cortical prostheses, in addition to restoring normal neurological functions, may serve to expand natural perceptual capabilities in mammals.

Study in Nature Communications: Perceiving invisible light through a somatosensory cortical prosthesis

More from Nicolelis Lab at Duke Medical Center…

(hat tip: Neurogadget)