Mechanisms for maintaining mental maps

Abstract

Neuroscience When an animal runs around, some hippocampal neurons are selectively active in specific locations called their place fields. A maplike representation created from many such place fields serves as a navigation mechanism. How such hippocampal maps stabilize is still unknown. Roux et al. investigated a discrete form of high-frequency neuronal oscillations called sharp wave ripples. In a spatial learning task, they focally silenced a subpopulation of hippocampal area CA1 neurons during sharp wave ripple events. The place fields of the silenced neurons were altered, and their spatial information content failed to increase. Control place cells, however, largely kept their spatial correlates and showed increased information after learning. Sharp wave ripple–associated neuronal firing is necessary for stabilizing and refining hippocampal place fields. Nat. Neurosci. 20 , 845 (2017).