SAN2020

Oscillations of the Thalamocortical (TC) circuit are related to the generation and maintenance of global rhythms that appear in the electroencephalogram (EEG) and that characterize functional states of the brain. The ability of the TC circuit to generate these oscillations lies in the combination of the intrinsic properties of the neurons that form the circuit and their recurrent synaptic connections. It has been shown in genetically modified animal models that the lack of the low threshold calcium channel T decreases the delta wave component present in the EEG during N-REM sleep and produces alterations of the sleep cycle. In addition, the overexpression of IT in animal models produces an absence epileptic phenotype that includes the presence of Spike-Wave Discharges (SWDs): the EEG hallmark of the disease. The input of reticulothalamic neurons (nRT) onto TC neurons has a synchronizing effect through the activation of GABAB receptors. It has been proposed that this effect is involved in the hypersynchronization that characterizes SWDs. We develop a 3-compartment model that represents the morphology of TC neurons and added the relevant postsynaptic inputs to study how they interact with the intrinsic cellular physiology. In particular we studied how different temporal statistical distributions of synaptic nRT to TC neurons inputs affect entrainment, and how this is modulated by the physiological properties of the intrinsic ion conductances of TC neurons.