This article contains what appears to be fairly accurate and useful information; however, it contains no references to any studies which back up any of the information.  Can anyone provide references?  Basic research is preferable to review articles, in my opinion, because I have found that review articles fairly regularly cite sources that do not actually support the specific claim made in the review.  My current project involves the PVN, so I may be able to provide a few in the future, but I highly doubt that my set of knowledge is exhaustive.

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