Hippocampal spatial map represents the global structure of the environment rather than being aligned to local contrast cues

Understanding spatial navigation critically depends on uncovering how animals encode environmental information. Place cells in the hippocampus are essential for constructing spatial maps by encoding targets, landmarks, boundaries, and other environmental features. However, it has remained unclear whether or not specific mapping properties emerge in respect to contrasting environmental elements that do not physically restrict animal movement. In this study, we investigated the calcium activity of CA1 hippocampal neurons in mice using miniscope imaging while the animals explored an arena with contrasting colored elements incorporated into the floor design. Our results show that the place fields of CA1 neurons are preferentially concentrated in regions of environmental heterogeneity rather than within the contrasting elements themselves or in zones preferred by the mice. These findings suggest that CA1 hippocampal neurons integrate surface contrast signals into the broader spatial representation of the environment.