CNTNAP2 and Isaacs syndrome: 1. Serum and/ or CSF CASPR2-Ab: positive (CBA), high titer (≥1:100) is highly specific2. EMG: spontaneous neuromyotonia discharges, myoclonic potentials, spastic discharges, fasciculation potentials3. Cranial MRI:normal, or high signal in the medial temporal lobe on T2-weighted imaging, cortical atrophy, meningeal enhancement changes4. EEG: not specific, epileptic waves can be observed sometimes.