If these are built in as the same neural structures, they refer to the same sensory maps of the brain. Word and thing are an integrated unit in the brain system. What does this mean? The child will move hand when they say the word hand, they will automatically start to sit down if they say the word "sit down" at age two when they are just learning all this. Suppose you use the word in absence of the thing, when the thing is not coming in through the sensory system, but the word is? Here is a vibration which is going to resonate with a previously established vibratory set of responses in the brain. It will activate those, just the word, just the name itself, and in absence of the thing, what does the brain do? It creates a facsimile of it. It creates the next best substitute it can and we come up with.
The brain will create an inner in the absence of the exterior sensory image. Here is where word stimulates, not the sensory motor system, not the emotional cognitive system, but the highest cortical systems of the brain, to do what? To create, out of its own processes an image. Do you see the profound difference? We are not just processing what the reptilian brain and all the other animal brains can do, but creating an image that doesn't exist at all, in response to a name of that thing that does exist.
This leads us into play and imagination. As the adult uses all of these words, what starts happening in the child's mind? It starts responding with internal imagery in every case that it can. And that leads us to storytelling and table talk to the early child. We had eight children in my family and nearly always a lot of guests and it was a great big table and always filled with a lot of people, and adult table talk. I loved it. I didn't understand any of it but I loved it and I would see all these worlds that would form inside my mind stimulated by the words and feelings the adults were using. Their descriptions triggered in my mind internal images of what they were talking about.
Now, back to storytelling, which is an integral part of language development, language being the flow of inner imagery triggered by symbols and metaphors. You will find that the child responds to storytelling very early, even before they can talk. In storytelling the word, here comes in the word as a vibration, again, only sensory input, and that challenges the whole brain, not just to create an image in keeping with each word, but to create moving imagery, fluid imagery that follows the flow of the words. It sets up an inner world scenario, a whole inner world scene representing the story which is constantly shifting according to shifting of the words themselves. This is a major challenge of the brain and its development.
Randolph Caldecott (1846-1886). British. "And the Dish Ran Away with the Spoon"
The job is so enormous that the child goes into total entrainment. All of the energy moves into this creation of inner imagery. They go catatonic. The body stops all movement, their jaw drops down, their eyes get great big and wide, and they are literally not in this world. Their eyes are wide open, they are not looking at anything outwardly. They are looking at the marvelous world that is forming within.