LTS cells in cerebral cortex and their role in generating spike-and-wave oscillations

Alain Destexhe, Diego Contreras and Mircea Steriade

Neurocomputing 38: 555-563, 2001.

Copy of the full paper (PDF)

Abstract

Some types of epileptic seizures involve both thalamus and cerebral cortex, while other types can be evoked in the cerebral cortex without thalamic participation. We investigated the possible role of low-threshold spike (LTS) cortical neurons in the genesis of these intracortical seizures. We found LTS cortical neurons in cat area 5-7 in vivo, which properties could be modeled based on relatively weak densities of the T-type calcium channel. At the network level, a small minority of LTS pyramidal cells was sufficient to generate paroxysmal oscillations with spike-and-wave (SW) field potentials. These oscillations reproduce the properties of intracortical SW paroxysms observed in athalamic cats, such as the slow frequency (1.8-2.5 Hz). We suggest that calcium-mediated rebound mechanisms intrinsic to cerebral cortex can explain the genesis of intracortical SW activity.
See also the following related articles:

Destexhe A. Spike-and-wave oscillations based on the properties of GABA_B receptors. Journal of Neuroscience 18: 9099-9111, 1998.

Destexhe A. Can GABA_A conductances explain the fast oscillation frequency of absence seizures in rodents ? European Journal of Neuroscience 11: 2175-2181, 1999.


return to publication list
return to main page