Cholinergic effects on spectral properties of spike trains in rat cortical neurons

We investigated cholinergic modulation effects on synchronized burst activity of neurons in rat dissociated cortical cultures on electrode arrays, using a cholinergic agonist, carbachol (CCh). Application of CCh resulted in a loss of regularity, a less precise synchronization, and a fragmentation of the burst structure. We found that temporal properties of spike trains were well-characterized by a simple Poisson cluster-process model, which provided a precise insight into the temporal structure of spike trains and allowed quantitative fitting of the spectral changes induced by CCh. These results should help to elucidate the complex actions of cholinergic modulation on cortical cells in intact neural networks.