simple explanation of defining brain

[MOSFET]

hi all

in engineering point of view we can understand heart as pump where there are some inputs and outputs.

I would like to understand what is brain?

 
thanks   

[StriatumPDM]

The problem with metaphors is that they never correctly capture the entire system. The brain is neither comparable to a cooler (as thought by Aristotele), a clockwork, a cybernetic system, or a computer. Even the pump model of the heart is insufficient in many aspects.
Furthermore this leads to absurde reflections like: "The brain has inputs and outputs so it may be seen as pumping (in this case) signals. So the brain must be like a heart, because it too is considered a pump."

[sashakal]

This simple question is probably the biggest question of neuroscience.
I agree with ChantiPDM that a metaphore will not be a good description.
One of the reasons for it , is that the brain is a LIVE organism and therefor it is very difficult to medel it as something mechanichal. When you learn a basic cell biology course  (and all our body including the brain is built from cells), you understand how complex is the very basic element of life, and that it constantly changes over time (the cell reacts to outside signals, and changes it's properties and structure accordingly).
Therefor if you like a metaphore, I would model the brain as a massively parallel computer - or in the electronics world - an FPGA , when each of it's basic elements - the logical gates and wires can change their function over time (logical gates can perform different operations over time, and wires can rewire themselvs).
From this description follows that it's structure can be anything and constantly changes. This is why the brain is so complex !

[MOSFET]

Thanks all

Yes, sometimes it is difficult to define a simple description of something. However, as a human being simple explanation mean better understanding. It might be not 100% but our imagination could understand better. The difficulty comes from when the question to be answered to another person who does not have the same background.
 
At a university a student ask his teacher what is current? Then he answered as a flow of electrons. The student did not understand the meaning of that for a long time until a postgraduate student said to hem imagine current as a water flow inside a pipe. Although it is not correct 100%, he has better understanding at that stage.

[StriatumPDM]

Well, I agree with you about your "current" example. There you virtually describe the same activity or process which only has two names, depending on the context. The medium is simply substituted (water vs. electrons), but nevertheless it remains a flow. So, the process itself is the same (flow of a medium), only that man has invented context-dependent terms for it.

However, comparing entire systems, you cannot simply substitute it with another and then both are in essence the same.