Epileptic seizures are caused by abnormal excitation of brain neurons, whereas psychogenic nonepileptic seizures (PNES) are thought to be caused by psychological factors. These two disorders share certain clinical symptoms and often coexist. Medication or surgical treatment is instrumental in improving the prognosis and quality of life of patients with epilepsy, but in cases of PNES, disease education, psychotherapy, and environmental adjustment are recommended. Therefore, it is important to accurately differentiate epilepsy from PNES using careful neurophysiological and psychological tests and imaging studies.
 We present the case of a patient who had been diagnosed with PNES five years before the admission but was later found to have refractory temporal lobe epilepsy after deliberate psychological assessment and long-term video electroencephalography (LVEEG). The patient, a female in her fifties, was admitted to our epilepsy monitoring unit (EMU) for reassessment. She experienced a full-body spasm in her teens and began taking antiepileptic drugs. While using phenytoin, carbamazepine and nitrazepam together, her seizure did not get enough control and she also presented with seizures leading to loss of consciousness and falls, and received radical surgical treatment in her forties. After that, the seizures remitted temporarily. Sufficient antiepileptic drugs including levetiracetam was continued however, seizure suppression was not obtained and soon after the surgery, she began experiencing episodic loss of consciousness and falling whenever subjected to stress. Electroencephalography failed to disclose any abnormal epileptic waves, and the seizures appeared to be triggered by "mental causes." Based on these findings, we diagnosed her with PNES. During outpatient treatment, we listened attentively to the patient for clues to the cause of the disorder. However, as she frequently got injured during the seizures, she was admitted to the EMU for a thorough reassessment. Detailed history taking with her family revealed that many seizures had occurred even in the absence of "mental causes." The LVEEG recorded complex partial seizures with motor symptoms focused on the right temporal lobe, which were consistent with epileptic waves. The diagnosis was changed from PNES to right temporal lobe epilepsy, and vagus nerve stimulation surgery (VNS) was performed. The seizure frequency decreased, and the quality of life of the patient improved as a result of treatment.
 Many epileptic seizures are misdiagnosed as seizures induced by "mental causes." In such cases, a multidisciplinary approach that includes LVEEG can facilitate accurate diagnosis.
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