[The cortico-thalamic theory for generalised spike-wave discharges].
The origin of generalized absence epilepsy is still not known. In the last century, four theories have dominated the debate about the origin of the bilateral synchronous generalized spike-wave discharges associated with absence seizures: the "centrencephalic" theory [Penfield and Jasper], the "cortical" [Bancaud, Niedermeyer, Luders], the "cortico-reticular" theory [Gloor, Kostop[oulos, Avoli] and the "thalamic clock" theory [Buzsaki]. There is now some evidence that absence epilepsy, as studied in the WAG/Rij model, is a corticothalamic type of epilepsy. A new hypothesis is proposed which suggests that a cortical focus in the somatosensory cortex is driving the widespread corticothalamic networks during spontaneous absence seizures. This modern theory was given the name "hot spot' theory" [Meeren et al., 2002]. According to the present view three brain structures are critically involved and their integrity seems a minimal and sufficient condition for the occurrence of spike-wave discharges. Firstly, the reticular thalamic nucleus is involved and most likely its rostral pole. Secondly, the thalamocortical relay cells in the ventrobasal complex play a role and, thirdly and most importantly, the cerebral cortex with its epileptic zone. The zone in which the epileptic focus seems to be localised is located on the somato-sensory cortex, and more precisely in the area on which the peri-oral region including the upper lip, projects.
Meeren
H K M
HK
MEG Centre, Free University Medical Centre, Amsterdam, The Netherlands.
van Luijtelaar
E L J M
EL
Lopes da Silva
F H
FH
Berdiev
R K
RK
Chepurnova
N E
NE
Chepurnov
S A
SA
Coenen
A M L
AM
D000818:Animals; D001921:Brain / Q000503:physiopathology; D002540:Cerebral Cortex / Q000503:physiopathology*; D004195:Disease Models, Animal; D004832:Epilepsy, Absence / Q000503:physiopathology*; D006801:Humans; D020646:Intralaminar Thalamic Nuclei / Q000503:physiopathology; D051381:Rats; D013788:Thalamus / Q000503:physiopathology*