Detecting Chemicals Through Bone

MTorrice writes "To understand the brain and its chemical complexities, researchers would like to peer inside the skull and measure neurotransmitters levels as the brain at work. Unfortunately, research methods to measure levels of chemicals in the brain require drilling holes in the skull, and noninvasive imaging techniques, such as MRI, can't detect specific molecules. Now, as a first step toward a new imaging tool, chemists report they can detect molecules hidden behind 3- to 8-mm-thick bone."

Question

[excelsior_gr]

Isn't MRI practically NMR? NMR is used for chemical analysis. Then how come MRI machines can't be programmed to do the same?

It's NUCLEAR magnetic resonance

[localroger]

NMR only reports the presence of (certain isotopes of) nuclei. With most biochemicals of interest being made almost entirely of the same four atoms (carbon, hydrogen, oxygen, and nitrogen) there's nothing to tell the MRI which particular large molecule the atoms are part of.

Re:It's NUCLEAR magnetic resonance

[venicebeach]

The summary is overly dismissive of existing techniques.

In addition to MR spectroscopy, [wikipedia.org] chemical activity in the brain can be measured with techniques like PET [wikipedia.org] and SPECT [wikipedia.org].

All of these techniques have their advantages and disadvantages, and its certainly always great to have new options.