. 2013 Apr 4;7:50. doi: 10.3389/fnins.2013.00050
Copyright © 2013 Piatti, Ewell and Leutgeb.
This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in other forums, provided the original authors and source are credited and subject to any copyright notices concerning any third-party graphics etc.