People with mesial temporal lobe epilepsy have altered thalamo-occipital brain networks

•In TLE, functional connectivity of PuL with lateral occipital lobe is less positive.•Functional connectivity of CL with medial occipital lobe is less negative.•Temporal lobe epilepsy has altered ALFF in ipsilateral PuL, and the lateral and medial occipital lobe.•Altered occipital lobe ALFF correlates with lower scores on Rey Complex Figure Test.•After epilepsy surgery, functional connectivity of CL, but not PuL, improves. While temporal lobe epilepsy (TLE) is a focal epilepsy, previous work demonstrates that TLE causes widespread brain-network disruptions. Impaired visuospatial attention and learning in TLE may be related to thalamic arousal nuclei connectivity. Our prior preliminary work in a smaller patient cohort suggests that patients with TLE demonstrate abnormal functional connectivity between central lateral (CL) thalamic nucleus and medial occipital lobe. Others have shown pulvinar connectivity disturbances in TLE, but it is incompletely understood how TLE affects pulvinar subnuclei. Also, the effects of epilepsy surgery on thalamic functional connectivity remains poorly understood. In this study, we examine the effects of TLE on functional connectivity of two key thalamic arousal-nuclei: lateral pulvinar (PuL) and CL. We evaluate resting-state functional connectivity of the PuL and CL in 40 patients with TLE and 40 controls using fMRI. In 25 patients, postoperative images (>1 year) were also compared with preoperative images. Compared to controls, patients with TLE exhibit loss of normal positive connectivity between PuL and lateral occipital lobe (p