Frequently, hearing professionals refer to Auditory Processing as a bottom-up phenonemon. What does this mean exactly?

Think of a beautiful tree with leaves and branches and blossoms. That’s what first catches our eyes. This magnificent canopy would represent the cortex of our brain. This canopy, or cortex, is the made of millions of generals who are waiting for information from the  intelligence community of the outside world  in order to determine what is true, what needs to be done, and to send their orders out to the “troops.” However, this canopy would not be able to survive were it not for the truck that it sits on that provides the leaves with nutrition obtained from its roots.

In much the same sense, our cortex relies up a structure called the brainstem. That is our trunk. The brainstem collects all the information from our world and sorts it into the proper “basket,” auditory or visual, or tactile, or emotional, or taste, etc. Then this sorted information is sent to the appropriate conveyor belt and transported to the general in the cortex who is waiting. This process goes from the bottom of the brainstem to the top of the cortex. Thus, a bottom-up direction.

Now it is also possible that the general gets the correct information but misinterprets it. So the orders/directions sent to the troops is incorrect. This is a top-down problem.

In order to provide the correct therapy to the individual, it must be determined where in the brain the problem lies and whether the process affected is bottom-up or top-down in origin.