Abstracts

Rationale: Thalamocortical network has been hypothesized to play a crucial role in the fundamental pathogenesis underlying secondary generalization of focal seizures. This study aimed to explore whether thalamic resting-state functional connectivity (FC) is altered in patients with non-lesional neocortical epilepsy and with secondary generalization of seizures.Methods: Resting-state functional magnetic resonance imaging (MRI) data were obtained from 16 patients with focal neocortical seizures and 16 healthy controls. All patients had normal structural MRIs and were categorized into benign epilepsy for receiving monotherapy and limited numbers of generalized convulsions. Whole-brain voxel-wise analyses were applied to extract the thalamic resting-state functional networks. The altered FC pattern in epileptic patients was evaluated in comparison to normal subjects.Results: Compared to the healthy controls, the left inferior temporal gyrus, left middle frontal gyrus, right inferior frontal gyrus (triangular part), and right superior frontal gyrus (dorsolateral) exhibited increased FC with the thalamus (p<0.05, AlphaSim corrected, cluster size>54) in the patients with SGNS. The right insula and right median cingulate and paracingulate gyri exhibited decreased FC with the thalamus (p<0.05, AlphaSim corrected, cluster size>54).Conclusions: Even our patients have rare generalized seizures, their thalamo-default mode network still has certain degrees of anomaly. These results highlight the functional importance of the thalamus in epilepsies.