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Neurosci. 6:93. doi: 10.3389/fnins.2012.00093 This article was submitted to Frontiers in Decision Neuroscience, a specialty of Frontiers in Neuroscience. Copyright © 2012 Morgado, Silva, Sousa and Cerqueira. This is an open-access article distributed under the terms of the Creative Commons Attribution Non Commercial License, which permits non- commercial use, distribution, and repro- duction in other forums, provided the original authors and source are credited. Frontiers in Neuroscience | Decision Neuroscience June 2012 | Volume 6 | Article 93 | 6