The hippocampus is not only the most beautiful of all brain structures, it is also the most
important. Not surprisingly therefore it has been intensely studied. The prevailing view
which dominates the literature is that the role of the hippocampus is to process spatial
information and to form spatial memories. This is based on (i) the claim that hippocampal
lesions affect performance on spatial tasks and not on non-spatial tasks, (ii) that the unit
activity of hippocampal principal cell activity represents the spatial location of the animal
(so called place cells), and (iii) synaptic plasticity, and in particular an NMDAR-dependent
LTP-like mechanism, in the hippocampus provides the mechanism by which long-term
associative spatial memories are formed and stored. But is it really so straightforward, and
are these key pieces of evidence really so watertight? All will be revealed!