How much of our brain do we need to survive?
As it seems, just 25% of our brain tissue is required to execute all of the tasks that most of us do daily: working, raising children, keeping a healthy relationship, shopping, cooking, etc. It poses two critical questions.
First, why do we need so much additional brain tissue when we can get through with up to 75% less? Second, why do some people change so drastically after minor injuries, yet others can function flawlessly with such a tiny amount of brain mass? Presumably, the answer to the first question is that we don’t require the extra brain tissue as long as our remaining neurons can multitask adequately.
In most circumstances, having too little brain mass is a disadvantage. As a result, it would have to get eliminated from the evolutionary gamble. Regarding the second question, having brain damage after the brain’s neurons have already specialized is likely to be more disruptive than being born with less brain tissue that can handle all of the necessary activities over time.