Cortex: the cortex in the human brain is the youngest part of the brain from the evolutionary point of view. It is primarily responsible for all cognitive activities i.e. all higher and advanced intellectual properties like speech, technical capacities, music, thoughts etc. It developed in humans originally from the olfactory part of older brain regions. In Homo sapiens the surface of the cortex is extremely enlarged by multiple folding. Due to anthropologists this extreme enlargement occured in the human evolution during the last 1 million years and is one of the main reasons why we could develop such skills and eventually cultures and civilisation.

brainstem: The brainstem is called the region of the human brain which is regulating most of the vegetative, physiological and automatic functions of our body. Evolutionary seen the brainstem developed from our earlier ancestors, primitive vertebrates. Basically the oldest brain stem regions (for example those regulating our sexual behaviours) are equivalent to those in reptiles or even fish.