Nature has an article that discusses candidate neuro-mapping technologies that may form the basis of the billion dollar brain projects that are just kicking off on either side of the Atlantic.
Both Europe’s and Obama’s brain projects have set themselves the (possibly over-) ambitious goal of mapping the working brain on the neuron-by-neuron level.
This is off the back of new technologies that promise multiple-neuron fine-grained recording and systems to make sense of the date – but can only currently do it on a very small scale.
The Nature article looks at the most promising options and how they might scale to whole brain, or at least, ‘big chunk of brain’ level.
Attempting to take another leap farther, Jeff Lichtman at Harvard University in Cambridge, Massachusetts, and Winfried Denk of the Max Plank Institute for Neurobiology in Munich, Germany, are working with the German optics company Carl Zeiss on a new electron microscope that would image even thinner slices — 25 nanometres, or one-thousandth the thickness of an average cell. “Then you get to see every little damn thing in the brain, from every neuron to every subcellular organelle, from every synapse to every spine neck — everything,” says Lichtman.
It’s probably worth saying that the ‘mapping the whole brain as it’s working’ thing is spin. Considering there are about 100 billion or so neurons in the human brain that’s a lot of microchips you’d need mixing in with your brain.
Link to Nature article ‘Neuroscience: Solving the brain’
Mind Hacks 
“It’s probably worth saying that the ‘mapping the whole brain as it’s working’ thing is spin.”
But so is fMRI, speaking literally. Sorry, couldn’t resist!