Functional role of entorhinal cortex in working memory and information processing of the medial temporal lobe

Our learning and memory system has the challenge to work in a world where items to learn are dispersed in space and time. From the information extracted by the perceptual systems, the learning system must select and combine information. Both these operations may require a temporary storage where significance and correlations may be assessed. This work builds on the common hypothesis that hippocampus and subicular, entorhinal and parahippocampal/postrhinal areas are essential for these functions. We bring up two examples of models, one modeling in vivo and in vitro data from entorhinal cortex layer II of delay match-to-sample working memory experiments, and one modeling slice data from layer V showing cellular "integrator-like" intrinsically generated stable graded levels of spiking activity. In both cases we discuss how cationic currents might be involved and relate their kinetics and pharmacology to behavioral and cellular experimental results.