Functions of the Cerebral Cortex are important...
Did you guess it???
Yes-- the cerebral cortex is responsible for functions such as thought, memory, language, voluntary movement, information processing, reasoning, and perception.
So, does this mean that since humans have more cortical folding that they're more intelligence? Well, it apparently seems to correlate with their ability to process information, use language, right? Does that therefore mean they're more intelligent?
What does "intelligence" mean, anyway?