Photosensitivity Proof of Concept Trial

The purpose of this study is to determine whether patients who usually have abnormal electrical EEG responses when shown flashing lights will show a reduction in abnormal electrical activity when they take a single dose of 2 marketed drugs (carbamazepine and levetiracetam). If so, a similar study in the future may be able to identify promising new drugs for epilepsy. Patients who successfully complete the screening visit, will return 4 additional times and will receive either placebo (2 times) or a single oral dose of both carbamazepine 400mg and levetiracetam 1000mg in random order. During each of the study days, several procedures and intermittent photosensitivity (IPS) assessments will be performed at 5 pre-determined times over the course of the day, one pre-dose and 4 post-dose.