This is Scientific American's 60 Second Science.

I'm Christopher Intagliata.

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Back in ancient times, philosophers like Aristotle were already speculating about the origins of

taste and how the tongue sensed

elemental tastes like sweet and bitter, salty and sour.

What we discovered just a few years ago is that there are regions of the brain, regions of the cortex, where particular fields of neurons

represent these different tastes again, so there's a sweet field, a bitter field, a

sortie field, etc.

Nick Reba, a sensory neuroscientist at the National Institutes of Health.

Reba and his colleagues found that he can actually taste without a tongue at all,

simply by stimulating the taste part of the brain, the insular cortex.

They ran the experiment in mice with a special sort of brain implant, a fiber optic cable that turns neurons on with a pulse of laser light.

And by switching on the bitter sensing part of the brain, they were able to make mice pucker up as if they

were tasting something bitter, even though absolutely nothing bitter was touching

the tongues of the mice. In another experiment the researchers fed the mice a bitter flavoring on their tongues,

but then made it more palatable by switching on the sweet zone in the brain.

What we were doing here was adding the sweetness, but only adding it in the brain not in in what we were

giving to the mouse. Think adding sugar to your coffee but doing it only in your mind.

The results appear in the journal Nature.

Reba says the study suggests that a lot of our basic judgments about taste, sweet means good,

bitter means bad, are actually hardwired at the level of the brain.

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