Discuss whether the main structures and systems of the human brain are clearly defined in terms of whether they are responsible for higher-order (complex) and lower-order (simple) psychological capacities and functions.

A brief introduction into the human brain would be that it is made up of an intricate network of neurons, these are cells that receive and transmit electrochemical signals.  There are approximately 100 billion neurons and 100 trillion connections among them in a human brain.

The simplest possible creatures have incredibly simple nervous systems made up of nothing but reflex pathways. For example, flatworms and invertebrates do not have a centralised brain. They have loose associations of neurons arranged in simple reflex pathways. Flatworms have neural nets, individual neurons linked together that form a net around the entire animal….(short extract)