Modified:
one taste
This page is from my personal notes, and has not been specifically reviewed for public consumption. It might be incomplete, wrong, outdated, or stupid. Caveat lector.The brain doesn't have separate models of each of the sense gates (and thought). Instead it just stores each moment of perception as a single vector. A 'frame' of memory contains information about all of your senses (though some may be stronger than others). In the present moment (which is itself perhaps just the 'current frame' of memory) you can move your attention between the sense gates, but this is a smooth process - when you transition your attention from something you're seeing to something you hear, there is no hard 'jump'; you can move continuously through states where both are in your awareness to varying degrees. This indicates that these perceptions exist within a common space.
The "yoga of one taste" in mahamudra is about noticing that everything arising in experience has the 'same taste' of emptiness.
As a meditative exercise: try to find any boundary between your visual field and your felt sense of the inside of your head. They may seem separate, but is there anything solid between them?
A consequence of this shared representation would be that the brain builds a joint model of the sense gates. We can learn to expect that a sight will be accompanied by particular sounds or smells. Presumably this also extends to the inward sense gates: emotions ("feel in"), thought ("hear in"), etc.