Data from: wired together, change together: spike timing modifies transmission in converging assemblies

The precise timing of neuronal spikes may lead to changes in synaptic
connectivity and is thought to be crucial for learning and memory.
However, the effect of spike timing on neuronal connectivity in the intact
brain remains unknown. Using closed-loop optogenetic stimulation in CA1 of
freely moving mice, we generated unique spike patterns between presynaptic
pyramidal cells (PYRs) and postsynaptic parvalbumin (PV)–immunoreactive
cells. The stimulation led to spike transmission changes that occurred
together across all presynaptic PYRs connected to the same postsynaptic PV
cell. The precise timing of all presynaptic and postsynaptic cell spikes
affected transmission changes. These findings reveal an unexpected
plasticity mechanism, in which the spike timing of an entire cell assembly
has a more substantial impact on effective connectivity than that of
individual cell pairs.