Design: Using a new PET compound which is a highly selective 5-HT(1A) silent antagonist referred to as (18)FCWAY, we will attempt to detect abnormalities in serotonin receptors in vivo in patients with epilepsy. The patients will have (18)FCWAY serotonin receptor studies (which include (15)H2O-CBF PET) and high resolution T1-weighted MRI for co-registration. (18)FDG-PET will be performed in the patients as part of seizure focus localization. We will also test subjects for the serotonin transporter polymorphism associated with depression, and perform a standard depression battery.