To investigate the effect of abnormal electrical activity and seizure on cognitive function in patients with refractory frontal lobe epilepsy.

From August 2010 to August 2013, the clinical data of 42 patients with frontal lobe epilepsy (Engel classification grade Ⅰ) treated surgically at the Epilepsy Center, Yuquan Hospital, Tsinghua University were analyzed retrospectively. The reasoning ability, language ability, attention function, and executive function of the patients were analyzed, and the influence of the above factors on different cognitive function was investigated in accordance with abnormal electrical activity discharge index, sides, and seizure characteristics.

The Wisconsin Card Sorting Test of 42 patients was affected by the sides of abnormal electrical activity, the scores of the left side, bilateral sides, and multifocal abnormal electrical activities were decreased significantly (all P<0.01). Discharge index and seizure frequency during the waking period were the influencing factors for semantic processing score. When the number of discharges increased (>50%) or the secondary tonic-clonic seizures occurred frequently (>1 time/day), the semantic processing scores were decreased (all P<0.05). The sides of abnormal electrical activity and the secondary tonic-clonic seizures were the influencing factors for the semantic processing scores. When the electrical activity was located on the left side or bilateral sides, and multifoci or secondary tonic-clonic seizures, the speech processing scores of the patients were decreased (all P<0.05). The scores of three-dimensional mental rotation in patients with combined with frequent discharge during sleep (>50%) and secondary tonic-clonic seizures were decreased (all P<0.05).

Discharge index, sides of abnormal electrical activity, seizure frequency, and seizure types during waking and sleeping periods affects cognitive function in different degrees.

Epilepsy, frontal lobe; Cognition disorders; Electroencephalography; Discharge index