Reduced functinal connetivity between mediodorsal thalamic nucleus and anterior cingulated cortex in absence epilepsy

Thalamus and its interaction with cerebral cortex are considered essential in the generation and propagation of spike and wave discharge (SWD). Our objective is to evaluate the spontaneous functional connectivity between the thalamus and cerebral cortex in absence epilepsy. We use the resting-state fMRI to determine the whole brain functional connectivity with the mediodorsal thalamic nucleus (MDTN) in 14 healthy controls and 12 absence epilepsy patients within interictal duration without epileptic discharge. Cross-correlation functional connectivity analysis reveals significant functional connectivities between MDTN and bilateral basal ganglia, insula, orbital frontal cortex, medial prefrontal cortex, anterior cingulated cortex (ACC), hippocampus, and midbrain in controls. Functional connectivity between thalamus and ACC is significantly lower in patients when compared with controls. Our finding, avoided IED effects, may reflect a permanent abnormality between thalamus and ACC in absence epilepsy patients. The abnormality may be considered as a substrate of seizure generation in absence epilepsy. The finding of this pilot study might contribute to the further investigation of the epileptogenic networks of generalized epilepsy.