Inhibition allocates spikes during hippocampal ripples.

ABSTRACT: Sets of spikes emitted sequentially across neurons constitute fundamental pulse packets in neural information processing, including offline memory replay during hippocampal sharp-wave ripples (SWRs). The relative timing of neuronal spikes is fine-tuned in each spike sequence but can vary between different sequences. However, the microcircuitry mechanism that enables such flexible spike sequencing remains unexplored. We recorded the membrane potentials of multiple hippocampal CA1 pyramidal cells in mice and found that the neurons were transiently hyperpolarized prior to SWRs. The pre-SWR hyperpolarizations were spatiotemporally heterogeneous, and larger hyperpolarizations were associated with later spikes during SWRs. Intracellular blockade of Cl^--mediated inhibition reduced pre-

SUBMITTER: Noguchi A 

PROVIDER: S-EPMC8917132 | biostudies-literature | 2022 Mar

REPOSITORIES: biostudies-literature