Zou, Li, and Buck: Odor maps in the olfactory cortex

Reading the paper posted by aquaeri in comments to this interesting post.

(PNAS++ for making the article available online. Oh, ah, they manage that by charging the authors $1000 to exercise the Open Access option. authors++)

What I got:

• A given odorant excites a widespread clumpy pattern over the anterior piriform cortex (APC).
  
• Similar odorants have similar patterns.
  
• Even different odorants have overlapping swathes. (I.e. they hit some neurons very near each other.)

Still up in the air:

• For all I can see here, the patterns in APC could be just scramblings of the clustered odorant responses seen in olfactory bulb.
  
• For example, do we know that any APC neuron receives inputs from two distinct receptor clones?
  
• When similar odorants have similar patterns in APC, is that simply because they light up similar sets of olfactory receptors upstream? (The authors mention this for future work.)
  
• Is there any kind of processing being done in APC?
  
• Does position within the APC mean anything?

I'd love love love to see this paper's measurements of APC taken along
with ones of olfactory bulb. *That* could get you somewhere.

( more nattering in which I ask more questions about what things mean )