Object-translocation induces event coding in the hippocampus

Abstract

The function of CA1 region in the rat hippocampus is transversely organized, aligning with input profiles from the entorhinal cortex and the CA3-CA2 region. We asked how CA1 neurons respond diversely to various contextual changes along the transverse axis, and how it may be influenced by selective inputs from upstream brain regions. Neuronal activity across the entire proximo-distal extent of CA1 in Long-Evans rats was monitored under manipulations of spatial or non-spatial environmental cues. Our results identified three distinct patterns of cue representation that varied from the proximal to the distal end of CA1: a descending gradient in spatial information processing, an ascending gradient in representation of local object features, and a reverse J-shaped pattern in response to non-spatial cue manipulation. This heterogeneity is closely linked to the nature of information altered in the environment, suggesting an involvement of upstream cue-selective neurons in shaping CA1 function.