Local Contrast Elements of the Arena Floor Modulate CA1 Spatial Mapping in Mice

Encoding environmental information is a primary focus in neuroscience, as environmental context is crucial for the spatial orientation of animals. Place cells in the hippocampus play a key role in forming the spatial map of the surrounding space by mapping targets, environmental objects, various landmarks, and boundaries. However, it was previously unclear whether specific mapping properties exist for contrasting environmental elements that do not physically obstruct animal movement. In this study, we examined the calcium activity of CA1 hippocampal neurons in mice using miniscope imaging, alongside their behavior in an arena with contrasting colored elements on the floor. Our findings indicate that the place fields of CA1 hippocampal cells are concentrated in areas of environmental heterogeneity, rather than in the individual elements themselves or in areas preferred by the mice. This suggests that the contrasting surface signals of the environment are represented by CA1 hippocampal neurons within the overall spatial pattern.