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The parahippocampal region: corticocortical connectivity
1Department of Psychology, Brown University, Providence, Rhode Island 02912, USA. Rebecca_Burwell@Brown.edu
Annals of the New York Academy of Sciences
|July 27, 2000
Summary
The parahippocampal region
Area of Science:
- Neuroscience
- Comparative Anatomy
- Brain Connectivity
Background:
- The parahippocampal region surrounds the hippocampus in rodents and primates.
- It includes the perirhinal, postrhinal, and entorhinal cortices.
- These areas receive and process polysensory information.
Purpose of the Study:
- To review the cortical afferentation of the entorhinal cortex.
- To examine the segregation of sensory information within parahippocampal pathways.
- To understand the functional implications of differing cortical inputs.
Main Methods:
- Review of existing literature on rodent and primate brain connectivity.
- Analysis of polysensory input pathways to the hippocampus.
- Examination of projections from perirhinal and postrhinal cortices to the entorhinal cortex.
Main Results:
- Perirhinal cortex preferentially projects to the lateral entorhinal area (LEA).
- Postrhinal cortex preferentially projects to the medial entorhinal area (MEA) and caudal LEA.
- Direct neocortical input to LEA resembles perirhinal input; MEA input resembles postrhinal input, indicating parallel organization.
Conclusions:
- Polymodal associational input to LEA and MEA is segregated and organized in parallel.
- Intrinsic connections within parahippocampal regions further support information segregation into parallel pathways.
- This parallel organization is crucial for processing diverse sensory information for hippocampal function.
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