Spike transmission and synchrony detection in networks of GABAergic interneurons

The temporal pattern and relative timing of action potentials among neocort ical neurons may carry important information. However, how cortical circuit s detect or generate coherent activity remains unclear. Using paired record ings in rat neocortical slices, we found that the firing of fast-spiking ce lls can reflect the spiking pattern of single-axon pyramidal inputs. Moreov er, this property allowed groups of fast-spiking cells interconnected by el ectrical and gamma -aminobutyric acid (GABA)-releasing (GABAergic) synapses to detect the relative timing of their excitatory inputs. These results in dicate that networks of fast-spiking cells may play a role in the detection and promotion of synchronous activity within the neocortex.