Models of human hippocampal specialization: a look at the electrophysiological evidence

From an anatomical perspective, the concept that the anterior and posterior hippocampus fulfill distinct cognitive roles may seem unsurprising. When compared with the posterior hippocampus, the anterior region is proportionally larger, with visible expansion of the CA1 subfield and intimate continuity with adjacent medial temporal lobe (MTL) structures such as the uncus and amygdala. However, the functional relevance emerging from these anatomical differences remains to be established in humans. Drawing on both rodent and human data, several models of hippocampal longitudinal specialization have been proposed. For the brevity and clarity of this review, we focus on human electrophysiological evidence supporting and contravening these models with limited inclusion of noninvasive data. We then synthesize these data to propose a novel longitudinal model based on the amount of contextual information, drawing on previous conceptions described within the past decade.