What other components and what evidence do you have that such components exist?
Well...there is the endocrine system for instance that generates most of our emotions. Also our instinctive responses generated from the genes.
The mind is generated through various means...though it is possible that the brain is used as a central platform in these cases also. There is also the 'second' brain (enteric nervous system) centered around the stomach which has a major role in our mental processes.
Secondly, it is to be noted that some people have survived and even lived near normal lives almost without a brain.
https://www.cbc.ca/radio/asithappens/as-it-happens-thursday-edition-1.3679117/scientists-research-man-missing-90-of-his-brain-who-leads-a-normal-life-1.3679125************
When a 44-year-old man from France started experiencing weakness in his leg, he went to the hospital. That's when doctors told him he was missing most of his brain. The man's skull was full of liquid, with just a thin layer of brain tissue left. The condition is known as hydrocephalus.
"He was living a normal life. He has a family. He works. His IQ was tested at the time of his complaint. This came out to be 84, which is slightly below the normal range … So, this person is not bright — but perfectly, socially apt," explains Axel Cleeremans.
Cleeremans is a cognitive psychologist at the Université Libre in Brussels. When he learned about the case, which was first described in The Lancet in 2007, he saw a medical miracle — but also a major challenge to theories about consciousness.
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