Computational Pattern Separation Models of Dentate Gyrus Neural Subpopulation in the Hippocampus

Hippocampus is a part of the brain that has an essential role in memory and learning. It is involved in many cognitive and behavioral phenomena, including the pattern separation process: the ability to distinguish patterns with very high similarity. The present study compared the models of pattern separation in the dentate gyrus of the hippocampus and aimed to investigate the significant cells and factors affecting pattern separation. In this review, we intend to describe the anatomy of the dentate gyrus as a part of the hippocampus, which has an essential role in pattern separation. Other adjacent neural populations are further addressed, too. Models of the dentate gyrus, including neurocomputation and functional, that represent the process of separating patterns in the dentate gyrus are reviewed and analyzed. In this regard, five major models were highlighted and compared from several perspectives. While some models are based on the entorhinal cortex and dentate gyrus regions, others point to the mediation of cornu ammonis (CA3) as well. Models with the lowest cells for pattern separation are addressed first. Finally, inhibition is discussed in the comparison of pattern separation models.