Functional imaging –How is it used? –What are its limitations? –What are the key elements?

Question

–How does it fit with classical methods?

This is in Neuroscience research, if that helps with context.

Answer 1

Wikipedia can answer these better than we can in this limited space:

http://en.wikipedia.org/wiki/FMRI (most popular functional imaging technique)
http://en.wikipedia.org/wiki/Functional_imaging

Answer 2

Functional imaging is performed with the help of Magnetic Resonance imaging.

You can see the brain working on the following basis (Ogawa, 1990):
When the brain works , it uses oxygen. Oxygenated haemoglobin is diamagnetic whereas depleted of oxygen haemoglobin is paramagnetic. This gives a different pattern in the images when the brain is working. So, when you collect the picture of the brain, you have a different signal when the brain is working
The link gives you more information