Abstract
Entorhinal cortical projections show segregation along the transverse axis of CA1, with the medial entorhinal cortex (MEC) sending denser projections to proximal CA1 and the lateral entorhinal cortex (LEC) sending denser projections to distal CA1. Previous studies have reported functional segregation along the transverse axis of CA1 correlated with the functional differences in MEC and LEC. Proximal CA1 shows higher spatial selectivity than distal CA1 in these studies. We employ a double rotation paradigm, which creates an explicit conflict between local and global cues, to understand differential contributions of these reference frames to the spatial code in proximal and distal CA1. We show that proximal and distal CA1 respond differently to this local-global cue conflict. Proximal CA1 shows incoherent response consistent with the strong conflicting inputs it receives from MEC and distal CA3. In contrast, distal CA1 shows a more coherent rotation with global cues. In addition, our study fails to show the difference in spatial selectivity between proximal and distal CA1 seen in the previous studies, perhaps due to richer sensory information available in our behavior arena. Together these observations indicate that the functional segregation along proximodistal axis of CA1 is not merely of more or less spatial selectivity but that of the nature of the different inputs utilized to create and anchor spatial representations.
Competing Interest Statement
The authors have declared no competing interest.