The aim of this chapter is to extend the standard simplified diagram of the connectional organization of the hippocampus found in many current textbooks, by adding details on the connectivity of area CA2 and on entorhinal intrinsic wiring. In the chapter, some of the ‘traditional wisdoms’ on hippocampal connectivity are discussed, emphasizing the need for a more inclusive framework to model the hippocampus. The chapter focusses on intrinsic connections, and many of the well-known extrinsic connections of the hippocampus will not be covered in this chapter, for two reasons. First, the information is already available at a summarized (meta) level, and a new summary would not assist those who need anatomical details to contribute to the explanation of the functional outcome of a study. Second, this chapter is meant to provide a framework of knowledge to support computational modelling of the region, and therefore only the most relevant and quantitative data on the connectivity of the hippocampus are covered.
Hippocampal formation Anatomy Parahippocampal region Topographical organization Entorhinal cortex
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The revision of this chapter has been supported by the Kavli Foundation, the Centre of Excellence scheme – Centre for Neural Computation and research grant # 191929 and 227769 of the Research Council of Norway and The Egil and Pauline Braathen and Fred Kavli Centre for Cortical Microcircuits.
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1.Kavli Institute for Systems Neuroscience, Centre for Neural Computation, and Egil and Pauline Braathen and Fred Kavli Centre for Cortical MicrocircuitsNTNU Norwegian University of Science and TechnologyTrondheimNorway