Figure 2.

(A) Illustration of the hippocampal long axis in rodent and human. Ventral and dorsal hippocampus in rodent correspond to anterior and posterior hippocampus, respectively, in human. ERC: entorhinal cortex. Adapted from Ref. [78]. (B) Hippocampal place fields differ in size along the hippocampal long axis; place fields in anterior hippocampus are larger than those observed in posterior hippocampus. Smaller place fields in posterior hippocampus may support coding of detailed event information (such as precise spatial position), whereas larger place fields in anterior hippocampus may integrate information across spatial positions to support coding of global context information. Adpated from Ref. [79]. (C) Anterior hippocampus represents memories for real-world events more similarly when they occur closer together in time. The temporal organization of memories within anterior hippocampus is even apparent at long time scales, such as one week and one month. Adapted from Ref. [63]. (D) Memory elements that share a common association with an overlapping item are represented differently within anterior and posterior hippocampus. Anterior hippocampal activation patterns become more similar for elements that share relationships, reflecting integration of overlapping events. In contrast, posterior hippocampal activation patterns for those same elements become more dissimilar after learning, reflecting the formation of orthogonal representations for overlapping events. Adapted from Ref. [22].