This excerpt is from The International Society of Experiential Professionals and is a good summary of why working experientially is important.
The bottom 80% of your brain, which is outside your conscious awareness (including your central nervous system), controls your thoughts, feelings, reactions, perceptions, sensations, and how you move in the world.
In contrast, the top 20% of your brain is known as “conscious awareness”, or in other words, where your brain is awake and cognizant of your surroundings.
Talk therapy (and even “trauma-informed” coaching) is designed to impact the 20%, or “conscious awareness”, whereas experiential therapy impacts the bottom 80% of our brain (where you live) as well as the top 20% (where you think), and even has the ability to impact muscle memory (how the body holds our experiences).
This means that the majority of your awareness is out of reach from the impact of talk therapy.
In other words, you cannot talk yourself out of a trauma response and simply “tell” yourself to be different.
from ISEP’s web page at https://isep.co/why-experiential/