Neuroscientists have known for a while that odor receptors in the nose send signals to the the brain’s taste center, also known as the gustatory cortex. But does the converse happen? Do taste receptors in the tongue talk to the smell center, the olfactory cortex?
New research suggests the answer is yes.
The smell center gets and uses information from the tongue even if an animal is not consciously sniffing — or even inhaling.

When a monkey is shown a video of one of its friends cooing or grunting, a visual stimulus goes to the auditory cortex, where it changes — enhances or suppresses — sound perception. That doesn’t happen when an image of a mechanical disk with a fake mouth accompanies the same sound. In other words, what the monkey sees literally affects what it hears.