A cortical cell ensemble in the posterior parietal cortex controls past experience-dependent memory updating

Animals refer to related past experiences when processing sensory inputs. The authors show that a cellular ensemble in the posterior parietal cortex that is activated during past experience mediates an interaction between past and current information to update memory through a circuit including the anterior cingulate cortex. When processing current sensory inputs, animals refer to related past experiences. Current information is then incorporated into the related neural network to update previously stored memories. However, the neuronal mechanism underlying the impact of memories of prior experiences on current learning is not well understood. Here, we found that a cellular ensemble in the posterior parietal cortex (PPC) that is activated during past experience mediates an interaction between past and current information to update memory through a PPC-anterior cingulate cortex circuit in mice. Moreover, optogenetic silencing of the PPC ensemble immediately after retrieval dissociated the interaction without affecting individual memories stored in the hippocampus and amygdala. Thus, a specific subpopulation of PPC cells represents past information and instructs downstream brain regions to update previous memories.

Automated summary

Animals refer to past experiences when processing current sensory inputs, and update previous memories through neural networks. This study reveals that a cellular ensemble in the posterior parietal cortex of mice interacts with the anterior cingulate cortex through a circuit to update memory by incorporating past and current information.