You should be suspicious of claims that a certain brain area is the epicenter of any given brain function. And you should try to avoid making these claims as well. The old adage, “one location, one function” is obsolete. The brain is highly complex, massively interconnected, and no one area solely performs any given function.
The idea of functions being conducted by a specific brain area is a holdover from how we originally learned about the brain. In the past, when a specific area of the brain was injured or surgically removed, scientists would carefully analyze subsequent changes in behavior to understand more about the function of that brain area. And while much was learned from this process of investigation, it has created a mental shortcut of considering that behaviors and functions are the domain of specific brain areas.
As technologies to study the brain have improved, our understanding of how the brain operates has expanded. Now, we think of functions as products of neural systems rather than of brain areas.
As an example, consider how we process spoken language. This function might be simplified by saying “Wernicke’s area in the temporal lobe is responsible for the comprehension of speech.” And yet, the path from detecting sound waves to understanding meaning involves many brain areas and multiple connections between them making that statement far too simplistic. Understanding spoken language requires cooperation between both hemispheres: the left for meaning of the words and the right for the intonation, inflection and emotional content that has a strong influence on understanding.
Another example is vision. The path from detecting light waves to perceiving an image involves a mind boggling number of steps along the way. In the visual system of a macaque monkey, 305 connections among 32 different brain areas were cataloged for this process in the early 1990’s. Since then, many new cortical areas have been discovered which dwarf this early estimate. These examples demonstrate how narrowing any specific function to just one brain area is a vast simplification.
How this information helps in explaining iLs:
As iLs practitioners, knowledge of the complex and interconnected nature of the brain is useful because it gives an opportunity to explain how iLs works. In all cognitive functions, there are multiple connections and relay stations for processing input. Cognitive efficiency is dependent upon adequate input from the brainstem and cerebellum and the smooth transmission of that input to higher brain areas.
iLs’ combined sound and movement approach stimulates sub-cortical activity, improving the ability of the brainstem and cerebellum to process sensory information leading to the cortex. And the consistent and persistent practice of processing this input that comes from iLs Focus programs helps to increase its transfer speed. With so many neural connections to be made, facilitating and accelerating this transmission improves cognitive performance.